ballast water management system submitted by germany ( imo )

8/3/2019 Ballast Water Management System Submitted by Germany ( IMO )

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E

MARINE ENVIRONMENT PROTECTIONCOMMITTEE62nd sessionAgenda item 2

MEPC 62/2/1017 December 2010Original: ENGLISH

HARMFUL AQUATIC ORGANISMS IN BALLAST WATER

Application for Final Approval of the SiCURE Ballast Water Management System

Submitted by Germany

SUMMARY

Executive summary: This document contains the non-confidential information related tothe application for Final Approval of the SiCURE Ballast WaterManagement System under the "Procedure for approval of ballastwater management systems that make use of Active Substances(G9)" adopted by resolution MEPC.169(57). This documentcontains a summary for translation purposes.1

Strategic direction: 7.1

High-level action: 7.1.2

Planned output: 7.1.2.5

Action to be taken: Paragraph 15

Related documents: BWM/CONF/36; MEPC 57/21; MEPC 60/2/15; BWM.2/Circ.13 andBWM.2/Circ.26

Introduction

1 Regulation D-3.2 of the International Convention for the Control and Management of

Ships' Ballast Water and Sediments stipulates that ballast water management systems thatmake use of Active Substances to comply with the Convention shall be approved by theOrganization.

2 Germany herewith submits an application for Final Approval according to theProcedure for approval of ballast water management systems that make use of ActiveSubstances (G9). This procedure stipulates the required information (MEPC 57/21, annex 1,paragraph 4.2.1), which, according to section 6, should be evaluated by the Organization. Inaccordance with BWM.2/Circ.26, Germany submits the non-confidential part of themanufacturer's application dossier in the annex of this document. The complete dossier willbe made available to the experts of the GESAMP-BWWG with the understanding ofconfidential treatment.

1The original document is over 20 pages long and can be found in English only in the annex hereto.


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3 Basic Approval of the Active Substance used has been granted at MEPC 60(MEPC 60/22, paragraph 2.4.1).

4 After carefully taking into account the recommendations contained in annex 6 of thereport of the tenth meeting of the GESAMP-BWWG (MEPC 60/2/11), the competent authority

has verified the application dossier and believes it to satisfy the requirements of Procedure (G9)adopted by resolution MEPC 169(57).

Summary of non-confidential information on the SiCURE Ballast Water ManagementSystem

5 The SiCURE Ballast Water Management System (BWMS) utilizes a proventechnology to filter out, oxidize and eliminate aquatic invasive species (AIS) with SodiumHypochlorite (NaOCl). NaOCl, a chlorine compound, has been used for many years toprevent marine growth in the seawater piping and heat transfer systems of land-based,offshore and shipboard installations. It has been found that the most efficient method ofhypochlorination is to produce sodium hypochlorite in situ, electrolytically, on demand,

utilizing Concentric Tube Electrode (CTE) technology to produce NaOCl and inject thesodium hypochlorite into the seawater intakes. This technology is well known in the maritimeindustry under trademark Chloropac. The experience with Chloropac on thousands ofshipboard installations worldwide has allowed Siemens to evolve its Chloropac MarineGrowth Prevention System into the SiCURE Ballast Water Management System.

6 The SiCURE BWMS is designed to provide a minimum required hypochlorite doseas demanded by the quality of the ballast water being treated. This is done employing filtrationand proprietary disinfection control. The electrical current to produce hypochlorite, andtherefore its dose level, is controlled by the demand in the receiving waters. The demand isexpressed by the oxidation reduction potential (ORP) in the treated water. On-demand biocidedosing is intended to reduce potential for corrosion and formation of disinfection by-productsas well as to minimize residual biocide concentration in the ballast water discharge. Anoptional dechlorination module will be installed for vessels with voyage times shorter than5 days. In this case sodium sulfite is used to neutralize remaining TRO in the discharge.

7 Siemens has carried out a comprehensive risk assessment analysis of performanceof the SiCURE system in accordance with Procedure (G9). Several disinfection by-productssuch as trihalomethanes, haloacetic acids, haloacetonitriles, chlorate and bromate wereidentified as Relevant Chemicals along with sodium sulfite used as a dechlorination chemical,when required. All these chemicals were investigated for their toxicity and other criticalproperties, either based on the results of the public literature search or by direct toxicitytesting. These effects were then compared with the toxicity of treated water from fresh water

and saltwater sources.

8 Treated water toxicity was evaluated during land-based testing conducted at theGreat Ships Initiative (GSI) test facility on fresh water Lake Superior (about 0.1 PSU) inWisconsin (United States) and at the Maritime Environmental Resource Centre (MERC) inbrackish water Chesapeake Bay (7 to 10 PSU) in Maryland (United States). Oxidantresiduals in all ten land-based tests with retention time of 5 days were below 0.1 mg/L. Asneutralization was not required in these test runs, an additional test using a neutralizationagent was undertaken, showing a potential neutralization system to work. Whole EffluentToxicity (WET) testing showed absence of acute toxicity in both fresh and brackish watertests meaning that discharge of treated water 5 days after treatment will not present anyimmediate adverse effect to the aquatic environment upon its discharge. WET test results in

fresh and brackish water do show some chronic toxicity to algae at 100% effluent but as littleas 50% dilution rendered treated water safe to the aquatic environment. There was notoxicity found in a trial with dechlorination, providing NOEC of 100% for all three trophic levels.


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9 The potential long-term adverse effects due to discharge were addressed using theenvironmental modelling Marine Anti-foulant Model to predict environmental concentration(MAMPEC Model, version 2) in the OECD-EU commercial harbour port. It was assumed thatthere were 80 ships anchored in the Port of Rotterdam on an average day, discharging 100,000(one hundred thousand) m3/day or about 4,167 m3/hour of ballast water into the harbour.

Further, it was assumed that all 80 ships present in the harbour are equipped with theSiCURE BWMS with the water characterized by the same holding time (Active Substanceand Relevant Chemicals levels). While in land-based tests, Active Substance concentration(TRO) after 5 days was below 0.1 mg/L, it was conservatively assumed here that TROconcentration in discharge was at 0.1 mg/L for all 80 vessels discharging in port.

10 Predicted environmental concentrations (PEC) for every Active Substance andRelevant Chemical were then compared with their Predicted No-Effect Concentrations (PNEC).The PEC/PNEC ratios listed below in the table indicate that no aquatic risk (ratio


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12 The Human Exposure Assessment section identified various population groups whocould potentially be exposed to the chemicals of potential concern (COPCs). Theassessment showed a low possibility of exposure for all of the population groups. Thetechnicians/ship's crew have some potential for inhalation exposure as a result of ventingfrom the ballast tanks and inspections that require technicians to go inside the tank.

However, the exposures estimated in this risk assessment are likely overstated due to theuse of highly conservative exposure assumptions and there are numerous safetymechanisms in place to prevent exposure under these circumstances. In summary, basedon the results of the conservative risk assessment, potential risks to on board receptors whomay be exposed to ballast water via inhalation or dermal exposures are below or withintypical acceptable risk ranges used in risk management decision making around the world.

13 It is important to note that the basic process used in the SiCURE Ballast WaterManagement System has been used for a long time to disinfect drinking water and bathingwater. There have been many toxicology studies conducted on both the Active Substancesand the disinfection by-products to develop health-protective guidelines for these chemicals.The potential risks to the safety of ships, human health and the environment are expected tobe low because of the low potential for exposure.

14 In conclusion, the risk assessment shows that the SiCURE BWMS treats ballastwater safely, in full compliance with the IMO Guidelines.

Action requested of the Committee

15 The Committee is invited to consider the proposal for Final Approval and decide asappropriate.

***


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MEPC 62/2/10Annex, page 1

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ANNEX

NON CONFIDENTIAL INFORMATION ON THE SICURETM BALLAST WATERMANAGEMENT SYSTEM

1 PREAMBLE

The structure of the dossier for Final Approval for the SiCURE BWMS follows the dossierfor Basic Approval as submitted to MEPC in December 2008 and approved by MEPC inMarch 2010. Changes in this application dossier are related to providing additionalinformation on:

- treated water properties analysed during land-based tests in fresh water ofLake Superior and brackish water of Chesapeake Bay;

- acute and/or chronic toxicity data for Relevant Chemicals;

- boundary conditions;

- risk to the aquatic environment (MAMPEC modelling);

- effect on corrosion; and

- assessment of additional human exposure scenarios.

Siemens' dossier for Final Approval also includes some information on the environmentalperformance of the SiCURE BWMS when equipped with an optional dechlorination

sub-system as it is Siemens intent to receive two type approvals: without the dechlorinationsystem for vessels engaged in long-term voyages and with dechlorination system for thevessels with short voyage times.

2 DESCRIPTION OF THE SIEMENS' SICURE BWMS

The SiCURE Ballast Water Management System (BWMS) utilizes a proven technology tofilter out, oxidize and eliminate aquatic invasive species (AIS) with Sodium Hypochlorite(NaOCl). NaOCl, a chlorine compound, has been used for many years to prevent marinegrowth in the seawater piping and heat transfer systems of land-based, offshore andshipboard installations. It has been found that the most efficient method of hypochlorinationis to produce sodium hypochlorite in situ, electrolytically, on demand, utilizing Concentric

Tube Electrode (CTE) technology to produce NaOCl and inject the Sodium Hypochlorite intothe seawater intakes. This technology is well known in the maritime industry undertrademark Chloropac. The experience with Chloropac on thousands of shipboardinstallations worldwide has allowed Siemens to evolve its Chloropac Marine GrowthPrevention System into the SiCURE Ballast Water Management System.

SiCURE BWMS is designed to provide a minimum required chlorine dose as demanded bythe quality of the ballast water being treated. This is done employing filtration and proprietarydisinfection control.

Pre-treatment of the ballast water with filtration is incorporated as a part of the SiCUREBWMS to remove or break down AIS and sediments sized at 40 microns and above. This

allows reducing NaOCl dose to provide required disinfection efficacy. Proprietary controllogic of the SiCURE system monitors the chlorine dose level necessary to provide the


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required efficacy. Biocide dosing level is variable and depends on the ballast waterconditions its physical, chemical and biological characteristics cumulatively called chlorinedemand. Matching dose level with the biocide demand allows minimizing unwanted effectssometimes associated with chlorine compounds.

The main features of the SiCURE BWMS and process are as follows:

- filtration (40 micron) to remove zooplankton, some phytoplankton and sediments;

- in situ produced Sodium Hypochlorite quickly destroys all AIS down to thebacteria level. Sodium hypochlorite oxidation is well documented proventechnology in shipboard and offshore applications;

- sodium hypochlorite decays quickly and will reach environmentally acceptablelevels during the ships voyage with little or no residual in the overboarddischarge after 5 days holding time;

- sodium hypochlorite, produced safely and economically in situ, eliminates theneed to store and handle hazardous chemicals on board;

- SiCURE BWMS Sodium Hypochlorite generators employ CTE technologyand thus are of low maintenance;

- centre-tapped electrochemical cells prevent stray currents in the ballast waterthus eliminating possible piping corrosion;

- SiCURE employs "On-Demand" hypochlorite dosing powered by Siemensproprietary ORP based control logic which allows automatic hypochlorite dosing

depending on ballast water conditions. This minimizes Active Substance andRelevant Chemicals residuals and corrosion;

- maximum dose level of NaOCl is limited to 6.0 mg/L;

- SiCURE employs a modular design that can be expanded to accommodate awide range of ballast water capacities;

- SiCURE can be supplied as loose components to accommodate retro-fitapplications as required; and

- as NaOCl decays relatively quickly, vessels with voyage time over 5 days will

be able to safely discharge treated water without any additional treatment.Vessels with short voyage times will require a dechlorination system.

2.1 SiCURE BWMS design and configurations

The Siemens SiCURE BWMS employs a two-stage treatment process used only on ballastwater intake see a block-diagram below. The first stage is the filtration to remove ordamage hard-to-kill zooplankton as well as some part of phytoplankton and sediments. Thefilter is installed directly into the ballast water main and has a bypass for ballast waterdischarge operations. The second stage is a proprietary disinfection with a biocide producedon board a ship in situfrom saltwater. The Active Substance is produced in a side stream ofthe ballast water main. Following the electrolyzer unit a degas tank is provided to allow the

entrained by-products, hydrogen and oxygen, to vent out upon safe dilution with air. ThenNaOCl is injected back into the ballast water main.


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Most of NaOCl is injected downstream of the filter to provide disinfection for filtered ballastwater. The NaOCl dose level is designed not to exceed a maximum of 6 mg/L in the treatedwater. This maximum is limited by continuous monitoring and control of the DC currentdrawn through the electrochemical cells.

Further, a small NaOCl stream is injected into the main upstream of the filter to provideNaOCl concentration of equal or less than about 0.1 mg/L to prevent it from bio-fouling andto break up the colonies of marine organisms.

Figure 2.1-1: Block diagram of the SiCURE ballast water management process

The core of the system is its Chloropac electrochemical generator. The electrolyzer

consists of a pre-determined number of cells arranged in series, called a train. The cells arehoused in an enclosure that provides additional personnel protection. To avoid highdifferential pressure over the cells, several trains installed in parallel are used for high ballastwater flows. This increases the size of a side stream. Table 2.1-1 provides an overview ofthe system configuration as well as the chemical composition of the concentrate that is fedinto the ballast water main. The concentration of biocide, as produced, will depend on a sizeof the system. For example, the systems used for treating 200 m3/h and 900 m3/h will usethe same side-stream flow of 5.5 m3/h, however, they will be producing biocide at theconcentration levels of about 220 mg/l and 1,000 mg/l, correspondingly. The SiCUREBWMS employs variable biocide dosing. Variable dose is achieved by maintaining theconstant side-stream flow and varying the DC current from the transformer-rectifier to meet aspecific biocide demand. Therefore, the biocide concentration in the side stream will vary.

FiltrationModule

BallastWaterTanks

ElectrochlorinationModule

BALLASTING

DE-BALLASTING

OptionalDechlorination

Module


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Table 2.1-1: SiCURE system configurations for different ballast water flows

SiCURE Systemcapacity /

Ballast Water Flow

RequiredChlorine

Dose

SideStream

Flow

Max NaOClConcentration in

Side Stream

Max NaOClConcentration in

Ballast Water Main

m3/h kg/h m3/h mg/L mg/L

200 1.2 5.5 218 6

400 2.4 5.5 436 6

500 3.0 5.5 545 6

600 3.6 5.5 655 6

800 4.8 5.5 873 6

900 5.4 5.5 982 6

1000 6.0 11.0 545 6

1500 9.0 11.0 818 6

2000 12.0 16.5 727 6

3000 18.0 22.0 818 6

5000 30.0 33.0 909 6

The current to produce chlorine, and therefore its dose level, is controlled by the demand inthe receiving waters. The demand is expressed by the oxidation reduction potential (ORP) inthe treated water. On-demand biocide dosing is intended to reduce potential for corrosionand formation of disinfection by-products as well as to minimize residual biocideconcentration in the ballast water discharge.

An optional dechlorination module will be installed for vessels with voyage times shorterthan 5 days. In this case sodium sulfite is used to neutralize remaining TRO in the

discharge. Materials of construction are type approved CPVC pipe, FRP, titanium andHastelloy-C. Filter is built of epoxy-coated carbon steel with a 904Lstainless steel screen.Integration with the shipboard ballast system will include startup, shutdown, emergencyshutdown and data acquisition communication protocols.

The SiCURE BWMS is set up to operate automatically with minimal operator supervision.The unit is controlled by a Siemens Programmable Logic Controller (PLC) programmed toinitiate operation when all the system prerequisites for the operation are satisfied.

A 3-D rendering of the containerized system is presented in Figure 2.1-2.

The system's mechanical equipment is composed of the following:

- automatic backwash seawater inlet filter with a backwash pump;

- seawater booster pump;

- electrochemical generator;

- degassing equipment;

- biocide dosing pump;

- ballast water analyser pump;

- orp control loop;

- automatic and manual valves; and- optional dechlorination module.


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The system's electrical equipment is composed of the following:

- transformer/rectifier;

- system control panel; and

- motor control centre.

The system's use of a side stream to produce NaOCl allows for a flexible footprint whereinsystem's components can be placed wherever the room is available in the engine or a pumproom that makes SiCURETM a good fit for retrofits see Figure 2.1-3.

Figure 2.1-2: 3-D Model of containerized SiCURE BWMS

FILTER

DEGAS TANK WITH

AIR BLOWERS

CHLOROPAC

GENERATOR

TRANSFORMER

RECTIFIER

ORP

CONTROL

BOOSTER

PUMP

DOSING PUMP

CONTROL

PANEL

SEAWATER

INLE


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Figure 2.1-3: 3-D View of the engine room with SiCURE BWMSfor 750 m3/h flow

3 IDENTIFICATION OF THE PREPARATION, ACTIVE SUBSTANCE,BY-PRODUCTS AND RELEVANT CHEMICALS (G9: 4.1)

Active Substance and Relevant Chemicals described in this section have been identifiedduring testing of the SiCURE system that had taken place at three separate locations,each with widely differing ecosystems. Bench-top, proof-of-concept testing was carried outby the Royal Netherlands Institute for Ocean Research (NIOZ) in the Netherlands usingNorth Seawater with salinity of about 30 PSU. Land-based testing has been conducted atthe Great Ships Initiative (GSI) test facility on fresh water (about 0.1 PSU) Lake Superior inWisconsin (USA) and at the Maritime Environmental Resource Centre (MERC) in brackishwater (6 1-0 PSU) Chesapeake Bay in Maryland (USA).

3.1 Active Substances and Preparations

SiCURE BWMS uses seawater to produce biocides in situusing principles of electrolysis.At the outlet of the electrochemical generator, seawater will contain several products ofelectrochemical reactions taking place at the anode and cathode surfaces of theCHLOROPAC generator. These are hypochlorous acid (HOCl) in equilibrium withhypochlorite ion (OCl-), hypobromous acid (HOBr) in equilibrium with hypobromous ion(OBr-), certain short-life oxygenated chemical compounds and oxygen gas (O2) generated atthe anode and hydrogen gas (H2) generated at the cathode. Hydrogen gas and oxygen gasare completely removed in the degas tank, therefore, they will be considered in thisapplication as irrelevant. The list of Active Substances as produced by the SiCUREBWMS and their expected concentration ranges are presented in Table 3.1-1. Table 3.1-2below provides an estimate of the relevant concentration of TRO in the treated ballast water

at the time zero after their injection into the ballast water.

TTRR

CCeellllss

CCoonnttrrooll

PPaanneell

MMCCCC

TTaannkk

FFiilltteerr


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Table 3.1-1: Active Substances as produced

Composition of Active Substances as produced

Component Chemical Name CAS Number Concentration, mg/l AS, RC or Other

Hypochlorous Acid 7681-52-9


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Table 3.3-1: List of Relevant Chemicals

List of by-products produced in ballast water and their concentration in g/L

Chemical Name Fresh water Brackish water Saltwater

T0 T5 T0 T5 T0 T5

Trihalomethanes:

Trichloromethane 127.2 34.0 236.2 20.3 < 0.5 < 0.5 N/A < 0.4

Bromodichloromethane 12.2 2.5 13.9 6.3 2.1 1.0 3.1 1.1 N/A < 0.4

Dibromochloromethane 0.6 0.1 0.7 0.1 28.8 37.0 24.9 4.1 N/A 2.9

Tribromomethane < 0.5 < 0.5 68.9 33.0 201.0 74.3 N/A 85.0

Haloacetic acids:

Dichloroacetic acid 51.1 6.3 27.0 28.3 1.3 0.1 1.3 N/A < 3

Trichloroacetic acid 87.1 21.9 92.2 6.4 < 1.0 < 1.0 N/A 0

Dibromoacetic acid < 1.0 < 1.0 45.2 15.0 23.1 23.3 N/A 50

Tribromoacetic acid < 4.0 < 4.0 71.6 71.8 167.2 122.8 N/A 60

Sodium Chlorate 404.0 32.1 406.0 26.1 262.5 77.8 299.5 65.4 N/A N/A

Sodium Bromate < 50.0 < 50.0 < 50.0 < 50.0 N/A 76

Dibromoacetonitrile < 0.5 < 0.5 22.5 5.0 12.3 9.7 N/A

Sodium Sulfite* NA


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The literature summarized below for acute toxicity shows that TRO, in general, and HOCl, inparticular, are more toxic to fish and crustaceans relative to Relevant Chemicals (Table 4.1.1-1).For example, the acute toxicity of TRO and HOCl to fish and crustaceans ranges from 0.032 upto 0.143 mg/L. The acute toxicity values of Relevant Chemicals are 2-3 orders of magnitudehigher. No acceptable exposure data for algae (minimum 72-hour exposure; OECD 201

Guideline requirement) were found for TRO and HOCl, however, the indications are that theyare toxic to algae.

Table 4.1.1-1: Acute Aquatic Toxicity

TestSubstance

FCA

Species Test Type LC50/EC50mg/L

NOECmg/L

Reference/Comments

Active SubstancesTRO (Fresh water) F Oncorhynchus mykiss 15-d survival 0.059 N/A Fisher et al. (1999)

C Daphnia magna 48-h survival 0.032 N/A Fisheret al. (1999)A Natural phytoplankton 47-h change in Chla

a(784 Mark and Hantink-deRooij, 1991

C Daphnia magna 48-h survival 1,098 AQUIRE, 1984A Phaeodactylumtricornutum

72-h growth rate 444 100 Hutchinson, 1994b

Trichloromethane F Lepomis macrochirus 96-h survival 14 N/A Anderson et al. (1979)C Artemia salina 24-h survival 30 N/A Foster and Tullis (1984)A Scenedesmus

subspicatus48-h growth

c(950) N/A Kuhn and Pattard (1990)

Tribromomethane F Cyprinodon variegatus 96-h survival 18 2.9 Heitmuelleret al. (1981)C Daphnia magna 48-h immobilization 46 N/A LeBlanc, G.A. (1980)A Skeletonema costatum 96-h growth inhibition 12.3 N/A U.S. EPA (1978)

Dibromochloromethane F Cyprinus carpio 72- to 120-h eggfertilization to hatch

34 N/A

Mattice et al. (1981)

C Daphnia magna 96-h survival 46.8 UMD (2010)A Isochrysis galbana 72-h growth 56.0 UMD (2010)

Bromodichloromethane F No data foundC No data foundA No data found

Dichloroacetic acid F Cyprinodon variegatus 96-h survival 321.6 UMD (2010)C Daphnia magna 24-h immobilization 106 N/A Trenel and Kuhn (1982)A Isochrysis galbana 72-h growth 52.3 UMD Study (2010)

Trichloroacetic acid F Pimephales promelas 96-h survival 2000 N/A Dennis et al. (1979)C Daphnia magna 48-h immobilization 2000 N/A Dennis et al. (1979)A Isochrysis galbana 72-h growth N/A 250.3 UMD (2010)

Dibromoacetic acid F Cyprinodon variegatus 96-h survival 352.9 UMD (2010)C Daphnia magna 96-h survival 259.9 UMD (2010)A Isochrysis galbana 72-h growth 195.5 UMD (2010)

Tribromoacetic acid F Cyprinodon variegatus 96-h survival 376.4 UMD (2010)C Daphnia magna 96-h survival 219.9 UMD (2010)A Isochrysis galbana 72-h growth 250.0 UMD (2010)

Dibromoacetonitrile F Pimephales promelas 96-h survival 490-620 TOXNET (2010)C No data foundA No data found


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TestSubstance

FCA

Species Test Type LC50/EC50mg/L

NOECmg/L

Reference/Comments

Sodium Sulfite F golden orfe 96-h mortality 220-460 BASF MSDSC Daphnia magna 48-h survival 89 BASF MSDSA Isochrysis galbana 72-h growth 48.1 BASF MSDS

NOTES:F = Fish; C = Crustacean; A = Algae.a. Study did not meet OECD 201 Guidelines because the test evaluated a change in chlorophyll

at 47 h rather than growth at 72 h.b. Study did not meet OECD 201 Guidelines because the test evaluated a growth at 24 h rather than

growth at 72 h.c. Study did not meet OECD 201 Guidelines because the test evaluated growth at 48 h rather than

growth at 72 h.

4.1.2 Chronic aquatic toxicity

The data given in Table 4.1.2-1 are the lowest toxicity values found in the literature or in the

UMD 2010 for each of the test substances for fish, crustaceans, and algae.

The literature summarized below for chronic toxicity shows that TRO, in general, and HOCl,in particular, are more toxic to fish and crustaceans relative to Relevant Chemicals. Thechronic toxicity of TRO to fish is 0.04 mg/L. The chronic toxicity of TRO to crustaceansis 0.012 mg/L. The chronic toxicity values of Relevant Chemicals are 2-4 orders ofmagnitude higher. No acceptable OECD 201 guideline exposure data for algae were foundfor TRO. No chronic data were found in the literature for hypobromous acid.

Relative to the Active Substances, bromate and chlorate are not very toxic to algae(8 and 62.6 mg/L). UMD 2010 study showed HAA NOEC values in the range of 70to 300 mg/L. Trichloromethane, which ranged from 1.5 up to 216 mg/L, is approximately2-3 orders of magnitude less toxic than TRO to fish, crustaceans, and algae. The NOECfor tribromomethane to algae was 10 mg/L which is less toxic than TRO. No acceptabledata could be found for the chronic toxicity of Tribromomethane to fish and crustaceans.No chronic data could be found for fish, crustaceans or algae exposed todibromochloromethane, bromodichloromethane, dibromoacetonitrile and sodium sulfite.

Table 4.1.2-1: Chronic aquatic toxicity

TestSubstance

FCA

Species Test TypeLC50/EC50mg/L

NOECmg/L

Reference/Comments

Active Substances

TRO (Fresh water)

F Ictalurus punctatus 134-d growth

a

N/A (0.005) Hermanutz et al. (1990)C Gammaruspseudolimnaeus

70-d fecundity N/A 0.012 Authuret al. (1975)

A Natural algae 24-d inhibition ofbiomass

b

N/A (0.079) Pratt et al. (1988)

TRO (Saltwater)

F Menidia peninsula 32-d egg to post-hatch

N/A 0.04 Goodman et al. (1983)

C Panaeus kerathurus 7-d growth/moltingc

N/A (0.079) Saroglia and Scarano (1979)A Natural

phytoplankton21-d reduction in celldensity

b

N/A (0.001) Sanders et al. (1981)

HOCl

F Oncorhynchuskisutch

23-d survival N/A 0.042 Holland et al. (1960)

C Americamysis bahia 7-d reproductionc

N/A 0.048 Fisheret al. (1994)A No data found

HOBrF No data foundC No data foundA No data found


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TestSubstance

FCA

Species Test TypeLC50/EC50mg/L

NOECmg/L

Reference/Comments

Relevant Chemicals

Bromate

F Morone saxatilis 10-d survivale

(93) (50) Richardson et al. (1981)C No data found

A Isochrysis galbana 7-d growth inhibition N/A 8 Erickson and Freeman(1978)

Chlorate

F No data foundC No data foundA Pseudokirchneriella

subcapitata96-h Growth Inhibition 62.6 Van Wijk et al., 1998

Trichloromethane

F Oryzias latipes 9-month growth N/A 1.5 Toussaint et al. (2001)C Daphnia magna 21-d reproduction N/A 13 Kuhn et al. (1989)A Skeletonema

costatum5-d reduction in cellvolume

477 216 Cowgill et al. (1989)

Tribromomethane

F No data foundC No data foundA Selenastrum

capricornutum96-h growth inhibition N/A 10 U.S. EPA (1978)

Bromodichloromethane F No data foundC No data foundA No data found

DibromochloromethaneF No data foundC No data foundA No data found

Dichloroacetic acidF No data foundC No data foundA No data found

Trichloroacetic acid

F Cyprinodonvariegatus

32-d survival 260.8 235.0 UMD (2010)

C Daphnia magna 21-d survival 249.5 285.0 UMD (2010)A Isochrysis galbana 96-h growth 78.5 UMD (2010)

Dibromoacetic acid


32-d survival396.6 277.0 UMD (2010)


Tribromoacetic acid


32-d survival590.8 508.5 UMD (2010)


DibromoacetonitrileF No data foundC No data foundA No data found

Sodium SulfiteF No data foundC No data foundA No data found

NOTES: F = Fish; C = Crustacean; A = Algae.

a. Study did not meet OECD 210 Guidelines because the test was initiated with juveniles rather thanthe egg stage.

b. Study did not meet OECD 201 Guidelines because the test did not have control culture biomassdata.

c. Study did not meet OECD 211 Guidelines because the test was not a 21-d reproduction test. Thetest did follow a portion of the protocol of the U.S. EPA OPPTS 850.1350 mysid chronic toxicitytest (U.S. EPA, 1996); however, molting was only observed for 7 days rather than the minimumof 28 days.

d. Study did not meet OECD 210 Guidelines because the test exposure was 23 days rather than therequired minimum of 28 days.

e. Study did not meet OECD 210 Guidelines because the test was initiated with 4-d old larvae (noteggs) and the post-hatch exposure was 10 days rather than the required minimum of 28 days.


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4.1.3 Endocrine disruption

No reports were found in the literature that indicated the Active Substances (TRO) may beendocrine disrupters in aquatic organisms. Likewise, no reports were found that indicatedthe Relevant Chemicals listed in the dossier may be endocrine disrupters in aquatic

organisms.

4.1.4 Sediment toxicity

Kocs for the Active Substances and Relevant Chemicals are presented in Table 4.1.4-1 ofthe Confidential Part of the Application Dossier. Neither the Active Substances nor theRelevant Chemicals appear to have the potential to be adsorbed to sediments to a significantextent basedon the adsorption coefficients (Kocs) for the chemicals summarized below. Allof the Kocs were


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4.2.1 Acute mammalian toxicity

Data for acute mammalian toxicity are presented in Table 4.2.1-1 of the confidential part ofthe application dossier. The lowest LD50s noted are for trichloromethane (36 to 2,000 mg/kg),bromate and dibromoacetonitrile (280 to 495 mg/kg). The LD50s for the other chemicals are

mainly above 500 to 1,000 mg/kg.

4.2.2 Skin, eye and sensitization effects

Data for Skin and Eye Effects are presented in Table 4.2.2-1 of the confidential part of theapplication dossier. No data could be found for sensitization effects for any of the chemicals.All of the chemicals have the potential to cause irritation to the skin and eyes at sufficientconcentrations. Where effects concentrations were provided, they were higher thanconcentrations typically found in treated ballast water.

4.2.3 Repeated-dose toxicity

Data for Repeated-Dose Toxicity Studies in a form of No-Observed-Adverse-Effects Levels(NOAELs) or Lowest-Observed-Adverse-Effects Levels (LOAELs), when available, arepresented in Table 4.2.3-1 of the confidential part of the application dossier. For many of thechemicals, the target organs were the liver and kidney. A typical range of NOAEL/LOAELvalues was within 10 100 mg/kg-day. Where effects concentrations are provided, they arehigher than concentrations typically found in treated ballast water.

4.2.4 Chronic mammalian toxicity

The results of chronic mammalian toxicity studies are listed in Table 4.2.4-1 of theconfidential part of the application dossier. The studies are conducted in rodents over a

period of two years. Some of the chemicals report liver and kidney effects, similar to thesubchronic studies. Some of the chemicals show an increase in specific tumours, usually inone species. Where effects concentrations are provided, they are higher than concentrationstypically found in treated ballast water.

4.2.5 Developmental and reproductive toxicity

Data on developmental and reproductive toxicity in rodents are presented in Table 4.2.5-1 ofthe confidential part of the application dossier. For many of the chemicals, there were noeffects noted on fertility or health of the fetus, even at the relatively high doses used in thestudies.

4.2.6 Carcinogenicity

Data on carcinogenicity, including carcinogenic classification for the chemicals by theInternational Agency for Research on Cancer (IARC) and other agencies in the United Statesand Canada, are listed in Table 4.2.6-1 of the confidential part of the application dossier.A few of the chemicals were not classified (hypobromous acid, tribromoacetic acid) by IARC,and there is no information in the literature suggesting that they should be classified aspotentially carcinogenic. Some of the chemicals are listed in IARC Group 3 not classifiableas to carcinogenicity in humans, while many are suspected as possible or probablecarcinogens based on animal studies.


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4.2.7 Mutagenicity and genotoxicity

Data on mutagenicity and genotoxicity are presented in Table 4.2.7-1 of the confidential partof the application dossier representing the results of various mutagenicity and genotoxicityassays. A wide range of results was observed for the different chemicals, and the different

tests. Several studies have shown that sodium hypochlorite produces mutagenic responsesin bacterial systems and mammalian cells in vitro. However, there is no evidence of activityin mammalian test systems in vivo. There were some mixed positive/negative results forTHMs and chlorate/bromate, mainly negative results for haloacetic acids and positivemutagenicity results in several in vitroand some in vivoassays for dibromoacetonitrile.

4.2.8 Toxicokinetics

Data on toxicokinetics are presented in Table 4.2.8-1 of the confidential part of theapplication dossier. Most of the chemicals are excreted in the urine over the course ofseveral hours, indicating relatively short half-lives in the human body. Trichloroacetic acidappeared to have the longest half-life. Some of the chemicals metabolize into breakdownproducts, such as trichloroacetic acid and dichloroacetic acid that are also rapidly eliminatedfrom the body.

4.3 Data on environmental fate and effect under aerobic and anaerobic conditions(G9: 4.2.1.3)

4.3.1 Modes of degradation (biotic and abiotic)

Aerobic degradation TRO, hypochlorous acid and hypobromous acid decay in seconds tohours as discussed in section 7.3.2 and in Heltz (1981), thus, little or no aerobic degradationis expected. Biodegradation of the Relevant Chemicals in presented in Table 4.3.1-1 of theconfidential part of the application dossier. Most of the Relevant Chemicals degrade slowly,with half-lives in the range of weeks or months. Sodium sulfite degrades quickly with ahalf-life of about 10 minutes. When no degradation data were available, no degradation wasassumed in the risk assessment.

Anaerobic degradation TRO, hypochlorous acid and hypobromous acid decay in secondsto hours as discussed in section 7.3.2 and in Heltz (1981), thus, little or no anaerobicdegradation is expected. Biodegradation of the Relevant Chemicals in presented inTable 4.3.1-2 of the Confidential Part of the Application Dossier. Most of the RelevantChemicals degrade slowly, with half-lives in the range of days or weeks.

4.3.2 Bioaccumulation, partition coefficient, octanol/water partition coefficient

The octanol/water partition coefficients (Pows) and bioaccumulation factors (BCFs) for theActive Substances and Relevant Chemicals are given in section 4.1.5 above. Theadsorption coefficients (Kocs) for the Active Substances and Relevant Chemicals are givenin section 4.1.4.

4.3.3 Persistence and identification of the main metabolites in the relevant media

It is well documented that free available chlorine will react in fresh water to form a number ofchloro-organic compounds, oxidation products, and chloride. Likewise, it is well documentedthat chlorine will react with Br- in saltwater to form free bromine which reacts with nitrogen toform bromamines which in turn form a number of bromo-organic, oxidation products, and Br-.All Relevant Chemicals discussed in this dossier, except for sodium sulfite, are theby-products expected from the chlorination of fresh water and saltwater ballast. Thepersistence of the above by-products is given in section 4.3.1.


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4.3.4 Reaction with organic matter

Several oxidant decay reactions have been identified. The principal types of decay reactionswhich can ultimately react with organic matter are: (1) oxidation of amino-nitrogen(breakpoint reaction) which in turn react with organic matter; (2) oxidation of carbon; and

(3) organic substitution. The most important decay reactions are probably those associatedwith the oxidation of amino-nitrogen which are important in the breakpoint phenomena of thechlorine-ammonia system. The breakpoint reactions are a function of chlorine dose,amino-nitrogen concentration, pH, temperature, and time of reaction.

Trihalomethanes are unquestionably ubiquitous products of chlorination. Several variablescan affect THM yields which include pH, temperature, chlorine dose, total organic carbon,and type of chlorine residual. Other factors being equal, higher pH tends to produce higherlevels of THM after a given contact time. Higher temperatures accelerate the rate of THMappearance, however, it is not clear whether temperature affects the ultimate yield.Increasing chlorine dose increases yield up to point, however, several studies indicate that a

plateau is reached. THM yields correlate positively with total organic carbon, but there is agreat deal of scatter.

Oxidation of carbon can play an important role in oxidant decay when natural watercontaining various amounts of organic matter are chlorinated. CO2 has been shown to be amajor product of chlorination of natural estuarine water. Halocarbons have been shown tooccur to a lesser degree by carbon oxidation. The production of halocarbons by substitutionreactions also constitutes a decay mechanism for chlorine. However, the literature indicates(Helz, G.R. 1981) that only a few per cent of the chlorine in typical doses is consumed insubstitution reactions during the decay process.

4.3.5 Potential physical effects on wildlife and benthic habitats

No data were found that indicated the Active Substances and Relevant Chemicals couldcause potential physical effects to wildlife.

4.3.6 Potential residues in seafood

Based on the log Pows and BCFs of the Active Substances and Relevant Chemicals, it isunlikely that significant residues will accumulate in tissues which in turn could impact theconsumption of seafood. No data were found that suggest that the Active Substances andRelevant Chemicals impart a foreign flavour or odour in the organisms exposed to thechemicals.

4.3.7 Any known interactive effects

No interactive effects of the Relevant Chemicals with fresh and salt ballast water have beenidentified.

4.4 Physical and chemical properties of the Active Substances, RelevantChemicals and treated ballast water (G9: 4.2.1.4)

Please see Table 4.4-1 of the confidential part of the application dossier. MSDS forActive Substances and Relevant Chemicals are presented in appendix B of the confidentialpart of the application dossier.


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4.5 Analytical methods at environmentally relevant concentrations

Several accredited environmental laboratories for environmental analytical services wereused: Enviroscan Analytical Services, Rothschild, WI (USA); Underwriters Laboratories(UL), South Bend (USA); Analytical Laboratory Services, Inc., Middletown, PA (USA); Weck

Laboratories, Inc., City of Industry, CA (USA). USEPA methods, including detection limits,used for analysis of Active Substances and Relevant Chemicals are presented in Table 4.5-1of the confidential part of the application dossier.

5 USE OF THE ACTIVE SUBSTANCE (G9: 4.2.6)

5.1 Manner of application and dosage

The SiCURE system applies Active Substance on intake only. SiCURE BWMS is basedon variable dosing necessary to achieve a certain oxidizing power of the treated water itsORP potential. Required chlorine dosing will be determined based on a certain ORP setpoint

and controlled by PLC to reduce or increase DC current drawn from the transformer-rectifierto the electrochemical generator as necessary. DC current is limited to produce no morehypochlorite than required to deliver 6 mg/L in ballast water.

The SiCURE system is designed for shipboard applications for both new builds and retrofits.The system can be supplied as a skid mount or containerized, fully integrated package or asloose components. SiCURE systems will be manufactured to treat from 200 to 5,000 m3/hballast water flow; with 6 to 8 standard size systems covering the entire range. The systemprimary market will be large ocean-going vessels such as tankers, LNG, bulkers andcontainerships.

For vessels with the short voyage time (under 5 days), a dechlorination sub-system will be

used for neutralizing treated ballast water on discharge. The system will consist of a storagetank and a dosing pump. Neutralization will be carried out using sodium sulfite solution at adose rate of up to 5 mg/L.

5.2 Retention time

In addition to the mandatory efficacy testing after 5 days (120 h) retention time specified by theIMO in Guidelines (G8), Siemens also carried out testing with only one day (24 h) retentiontime. The results of that test showed that the treatment with SiCURE system was effectivewithin the first 24 hours. As Siemens will be offering two alternative models of the SiCUREsystem, with and without a dechlorination module, therefore the retention time will be:

- 5 days to allow for TRO to dissipate to below 0.1 mg/L level for vessels with thevoyage time of more than 5 days. Land-based tests in Chesapeake Bay andLake Superior showed (Tables 7.2.1-1 and 7.2.1-2) that after 5 days' retentiontime, TRO in the treated water was found to be below 0.1 mg/L; and

- 24 hours for vessels with a short voyage time when dechlorination module is used.

5.3 System monitoring and control, crew interaction

SiCURE BWMS has a data acquisition system. PLC will collect and transmit to the dataacquisition system those parameters that are vital for the reliable performance of the filtrationand disinfection subsystems. The parameters will include differential pressure setpoint

(backwash trigger), differential pressure and backwash duration for the filter and ORPsetpoint, ORP value, DC current, DC voltage, electrochemical generator flow, differentialpressure in the hydrogen degas tank.


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Operation of the SiCURE system is provided in a fully automated mode and requiresminimum maintenance limited to the following:

- inspecting all SiCURE equipment prior to operation and after ballasting iscompleted;

- tightening any loose item in the system;

- performing visual checks of the system in operation. Maintain system tidinessand ensure equipment is operating properly. Log any observation;

- calibrating ORP sensors according to the maintenance requirements;

- checking the ORP monitor as appropriate. Log extreme changes in reading;

- checking the system data logger and examining the data recorded. Look forany variation;

- monitoring any abnormal alarm; and

- during discharge, in line with the water treatment industry practice, a crew willbe required to carry out a TRO grab sample analysis of the water beingdischarged using hand-held HACH analyser or equal.

NOTE: In accordance with GESAMP-BWWG's recommendations, Siemens will test an inlineTRO analyser and/or ORP monitoring during discharge at the time of shipboard testing.However, these instruments are usually unreliable at low TRO levels especially with dirtyseawater and in the presence of suspended solids. At this time grab sample analysis usinghand-held HACH analyser or equal is considered as a preferred option.

5.4 System locations, considerations and limitations

System locations and considerations Based on Siemens experience with Chloropac

shipboard applications, it is expected that every installation will require engineering worktogether with a shipowner, ship operator and a naval architect to determine the best locationand piping configuration for the SiCURE BWMS to provide for its safe operation.A location for each installation will have to be approved by a Classification Society.

While electrochlorination part of the SiCURE system can be installed at various locationssuch as in the engine or pump rooms or on a deck, it is preferred that the filter be installednear the ballast water pumps that are typically designed for low pressure.

Limitations Major limitation of the SiCURE BWMS is related to the manner the ActiveSubstances are produced on board the ship. SiCURE system produces Active Substancein a side-stream to a concentration of about 200 to 900 mg/L. This design was selected toeliminate any possibility of the hydrogen gas by-product from accumulating in the ballasttanks. To use the electrodes applied in the SiCURE process effectively the minimalsalinity in the side stream directed to the electrolyzer should not be below 14 g/L chloride.For ships that occasionally operate in fresh or brackish water this requirement will be met byfeeding the electrolyzer with water with sufficient salinity stored in a dedicated ballast tankbefore entering the zone of low salinity.


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6 HAZARD CLASSIFICATION AND MATERIAL SAFETY DATA SHEETS(G9: 4.2.7)

Hazard identification for Active Substances and Relevant Chemicals is provided in Table 6-1of the confidential part of the application dossier. All referenced MSDS are provided in

appendix B of the confidential part of the application dossier.

7 RISK CHARACTERIZATION

7.1 Screening for persistence, bioaccumulation, and toxicity (G9: 5.1)

7.1.1 Persistence (G9: 5.1.1.1)

The Active Substances and sodium sulfite are not persistent. All other Relevant Chemicals arepersistent using Procedure (G9) criteria of a half-life >60 days in marine water or >40 days infresh water.

7.1.2 Bioaccumulation (G9: 5.1.1.2)

None of the Active Substances or Relevant Chemicals are expected to bioaccumulate usingProcedure (G9) criteria of a log Pow


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accompanied with dechlorination during discharge was also carried out by MERC. Treatedwater evaluation involved TRC/TRO analysis and Whole Effluent Toxicity (WET) testing.Both reports are available for review in Appendixes C, D and E, correspondingly, of theconfidential part of the application dossier. Endpoints values (EC50, NOEC, LOEC) observedduring WET tests are presented in Tables 7.2.1-3 and 7.2.1-4 1 of the confidential part of the

application dossier.

TRO values in all 10 tests with retention time of 5 days were below 0.1 mg/L. No acutetoxicity was observed across all 10 fresh and brackish water trials and all 6 fresh andbrackish water taxonomic species through the entire dilution series including 100% effluent.No acute toxicity was found in a 24-hour test with dechlorination. Chronic toxicity wasobserved in some test trials with 100% effluent, both fresh and brackish water. There wereno statistically significant (p


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chlorine dose level used for disinfection. As these by-products may present a risk potentialto the environment, their yields have to be minimized. Employing a variable, on-demandchlorine dosing will allow minimizing the concentrations of Relevant Chemicals in the treatedwater and, as a result, in the aquatic environment after discharge. On other hand, the samereactions result in a quick decay of the residual chlorine in the ballast tanks. Use of variable,

on-demand chlorine dosing allows minimizing the level of TRO in the treated water. Thesame reactions will also play a very important role of eliminating chlorine from the treatedwater being discharged in to the port harbour.

7.3.2 Characterization of degradation route and rate (G9: 5.3.5)

The main removal pathways for chlorine species in water are abiotic degradation (e.g., reactionwith other chemicals present in the water), volatilization and photolytic reactions.Biodegradation and bioaccumulation of chlorine species are not important and only chlorinatedorganic by-products would be bioaccumulated to any extent (Environment Agency, 2007).Abiotic degradation depends on the water quality (chlorine demand) and is difficult to predict.

As it was shown in our application dossier for the Basic Approval, the half-life due to abioticdegradation could be as short as seconds and as long as a few hours. Further analysis ofthe literature and internal testing showed that sunlight-induced photochemical decay ofoxidants including chlorine and bromine yields a half-life of about 0.2 to 0.8 hours.

7.3.3 Prediction of discharge and environmental concentrations (G9: 5.3.8)

As it was shown in section 7.2.1, there was no acute toxicity observed during WET tests in allland-based test trials both in fresh and brackish water with six fresh water and saltwateraquatic organisms representing three trophic levels.

In order to provide a conservative evaluation of potential chronic toxicity effects on the

aquatic environment by the discharge treated with the SiCURE system, in accordance withProcedure (G9), section 5.2.6, the Marine Anti-foulant Model to predict environmentalconcentration (MAMPEC, version 2) was used in this dossier to predict environmentalconcentrations of TRO in the OECD-EU commercial harbour port (Port of Rotterdam) waterafter discharge.

As a worst-case scenario, it was assumed in the MAMPEC Model that:

- all TRO is composed of the free available chlorine (FAC), by far the most toxichalogen compound. Further, the calculations were therefore all based on HOCl(as sodium hypochlorite); and

- considering unpredictable character of abiotic degradation of HOCl due tovariable chlorine demand, only photolytic degradation rate was considered in thismodelling study. The half-life of HOCl was selected conservatively at 1 hour.

It was assumed that there were 80 ships anchored in the Port of Rotterdam on an averageday, discharging 100,000 (one hundred thousand) m3/day or about 4,167 m3/hour of ballastwater into the harbour. These numbers for the Port of Rotterdam were used recently in thepublicly available dossiers of other BWMS developers and it is reasonable to maintain thesame scenarios in the current calculations (MEPC 61/2/4). Further it was assumed thatall 80 ships present in the harbour are equipped with the SiCURE BWMS with the watercharacterized by the same holding time (TRO level). While in land-based tests TROconcentration after 5 days was below 0.1 mg/L, it was conservatively assumed here that

TRO concentration in discharge was at 0.1 mg/L for all 80 vessels discharging in port.


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Results of modelling are presented in Table 7.3.3-1 as predicated environmental concentration(PEC) based on a 95% concentration value from the MAMPEC output file. Table 7.3.3-1 alsolists PECs for all Relevant Chemicals that were calculated using MAMPEC modelling in asimilar manner to HOCl modelling. Maximum values in the concentration range for RelevantChemicals found 5 days after treatment across all fresh water, brackish water and saltwater

trials (listed in Tables 3.2-3 and 7.3.3-1) were used in these calculations. All PEC values inTable 7.3.3-1 are based on a 95% concentration value from the MAMPEC output files. AllMAMPEC output files are presented in the appendix F of the confidential part of theapplication dossier.

PEC for sodium sulfite had to be calculated using an alternative method as its physicalparameters (Koc of 500, no vapour pressure and Henry constant) were outside of theMAMPEC parameters range. Details of PEC calculations for sodium sulfite are alsopresented in appendix F of the confidential part of the application dossier.

Table 7.3.3-1: Results of MAMPEC modelling for 80 ships

Chemical Name Max Concentration in dischargeat T5, gl

-1

Predictedenvironmentalconcentration

(95 Percentile),gl

-1

Freshwater

Brackishwater

Saltwater

TRO (as HOCl)


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7.3.5 Effects assessment

The toxicity data sets indicate that the risk of the Active Substances is negligible for mostfresh water and saltwater predators (fish) and consumers (crustaceans) based on a chronicNOEC


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Table 7.3.6-1: Predicted No-Effect Concentration (PNEC) for the Active Substancesand Relevant Chemicals in fresh water and saltwater

Chemical PNEC(g/L)

FactorApplied

Comment(s)

Active Substances

TRO 0.04 N/A EU PNEC of 0.04 g/L for HOCl wasused because the value is moreconservative than TRO

HOCl 0.032 1000 Lowest HOCl L(E)C50 from a fish,crustacean and alga

Relevant Chemicals

Bromate 8 1000 Lowest L(E)C50 from a fish and alga

Chlorate 62.6 1000 Lowest L(E)C50 and chronic NOEC froma fish, crustacean, and alga

THM -Trichloromethane 15 100 Lowest L(E)C50 and NOEC from a fish,

crustacean, and algaTHM -Tribromomethane 12 1000 Lowest acute data from a fish,

crustacean, and an alga

TTM-Bromodichloromethane 15 N/A Insufficient data; thus, aquatic PNECtaken from page 96 in EU (2007)

THM -Dibromochloromethane 34 1000 Lowest L(E)C50 and NOEC from a fish,crustacean, and alga

HAA -Dichloroacetic acid 52.3 1000 Lowest L(E)C50 and NOEC from a fish,crustacean, and alga

HAA -Trichloroacetic acid 785 100 Lowest chronic NOEC from a fish,crustacean, and alga

HAA -Dibromoacetic acid 978 100 Lowest chronic NOEC from a fish,crustacean, and alga

HAA -Tribromoacetic acid 1382 100 Lowest chronic NOEC from a fish,crustacean, and alga

Dibromoacetonitrile 490 1000 Lowest L(E)C50 and NOEC from a fish,crustacean, and alga

Sodium Sulfite 48 1000 Lowest L(E)C50 from a fish, crustaceanand alga

7.3.7 Effects on sediment

No acute or chronic whole sediment fresh water or saltwater toxicity data were found in theliterature for the Active Substances or Relevant Chemicals. The PNEC data for pelagic

organisms can be used to estimate potential risks to epifaunal sediment organisms. Asstated in section 7.3.4, the risk to infaunal sediment organisms is low based on the Kocswhich are all


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While there was some chronic toxicity observed in some land-based trials, a 50% dilution oftreated water would render discharge after 5-day holding time non-toxic to all three trophiclevels. Based on GSI data for TRO in dilution series, TRO NOEC of 22 g/L could becalculated using results of GSI discharge toxicity study. That provides a PNEC valueof 0.22 g/L (assessment factor of 100) or about 20 times greater than PNEC listed in

Table 7.3.6-1 thus providing a safety margin in PEC/PNEC calculations for TRO in theRisk Assessment of this application.

7.4 Risk to the aquatic environment

No acute toxicity found across the land-based trials in fresh and brackish water with andwithout dechlorination suggests that there is no immediate risk to the aquatic environmentupon discharge. Chronic toxicity observed in some of WET tests during land-based testingsuggests that there are some risks present to the aquatic environment in the long term thatneed to be evaluated.

Evaluation of the potential risk to the aquatic environment is based on a series of PEC/PNECratios using a worst case scenario. Given below in Table 7.4-1 are the PEC/PNEC ratios forActive Substance and Relevant Chemicals calculated using MAMPEC or Box (for sulfite)models for a scenario of 80 ships simultaneously discharging ballast water treated with theSiemens SiCURE BWMS in the Port of Rotterdam.

The PEC/PNEC ratios for Active Substances and Relevant Chemicals indicate that noaquatic risk (ratio


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8 RISK ASSESSMENT

8.1 Risk to safety of ship

A risk assessment is a method used to estimate the likelihood of adverse effects to human

health and the environment, based on toxicity and exposure information. The riskassessment section discusses potential risks to the safety of the ship, as well as potentialexposures and risks to human populations who could potentially come into contact withballast water containing chemicals from the SiCURE system.

8.1.1 Flooding

The SiCURE system is installed such that the ships ballasting system can runindependently of its operation. The connection to the ballast water piping system is made viaclass-approved automatic valves. In case of catastrophic failure of any of the components ofthe SiCURE system, the emergency stop would automatically close these valves resulting

in complete isolation from the ships ballast water piping.

8.1.2 Corrosion

In order to evaluate effect of the treatment with SiCURE BWMS, Siemens undertook areal-time six-month long testing program at their testing facility in Singapore. The study wasbased on recommendations for corrosion testing by the GESAMP-BWWG published indocument MEPC 59/2/16 in April 2009 and was conducted under supervision fromGermanischer Lloyd. As the GESAMP-BWWG recommended, the testing was executedusing a flow through setup with full strength seawater as a basis. The corrosion effects fromnatural seawater were compared to seawater with hypochlorite maintained at 6 mg/L(measured as chlorine) which represents the maximum treatment concentration of the

SiCURE system. Materials investigated included low carbon steel (shipbuilding steel),stainless steel, copper and nickel alloys as well as gasket materials and epoxy coatingapplied in ballast tank coatings. The tests were carried at ambient temperature atabout 302C.

Evaluation of uncoated metals included: (a) corrosion rate measurement (by mass loss) on amonthly basis per ASTM G31, (b) evaluation of crevice corrosion per ASTM G78 at the endof testing (6 months), (c) evaluation of pitting corrosion at the end of testing per ASTM G46.

Evaluation of coated carbon steel included: (a) Interim inspection: examination for blisteringper ISO 4628-2 on a bi-monthly basis, (b) final inspection (after 6 months), to examine thespecimens for blistering (ISO 4628-2), rusting (ISO 4628-3), cracking i(ISO 4628-4), flaking

(ISO 4628-5), delamination around the scribe (4628-8), and coating adhesion (ISO 4624).

Evaluation of EPDM and PTFE included: (a) visual by monthly inspections and(b) assessment of tensile strength per ISO 527 at strat and after 3 and 6 months of exposure.

Complete results of the corrosion study are presented in the appendix H of the confidentialpart of the application dossier for Final Approval.

Corrosion rate

Table 8.1.2-1 below provides results for immersion corrosion testing of shipbuilding carbonsteel A36 and other alloys after six months of testing. Equivalent annual corrosion rates

were calculated from the measured weight loss of the sample coupons.


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The test specimen for stainless steel barely experienced any mass loss. Brass andcupro-nickel showed rate in the range of micrometers per year. Only carbon steel A36showed significant corrosion rates around 0.1 mm/year. The corrosion rate in seawaterwhere NaOCl concentration was maintained at 6 mg/L was about 1.4-fold greater than inuntreated seawater.

Table 8.1.2-1: Immersion corrosion rate for uncoated coupons

Material Grade Treatment Corrosion Rate,mm/year

Carbon Steel A36 Seawater 0.075 0.001

6 mg/L NaOCl 0.108 0.003

Stainless steel SS316L Seawater 0.8E-04 0.3E-04

6 mg/L NaOCl 1.2E-04 0.4E-04

Aluminium Brass C68700 (CuZn20Al2) Seawater 2.7E-03 0.1E-036 mg/L NaOCl 2.8E-03 0.1E-03

Cupro-Nickel C71500, ASME SB171 (CuNi30Mn1Fe)

Seawater 5.6E-03 0.4E-03

6 mg/L NaOCl 8.9E-03 0.2E-03

The annual corrosion rates found in this study fall within the annual corrosion rate rangebetween 0.1 to 1.2 mm/year (BMT 2002) reported for untreated seawater ballast water tanksby The Tanker Structure Cooperative Forum, the most extensive publicly available databaseon corrosion rates in maritime industry.

Pitting corrosion

Carbon steel samples from the corrosion tests were evaluated by Germanischer Lloyd andshowed that pitting corrosion was evenly dispersed over the surface. The size and depth ofpits were within the lowest category given in ASTM G46. The density of pits in chlorinatedseawater was characterized as category A3-A4 (5.0 E+04 to 1.0 E+05 per m2), slightly abovethe untreated seawater, which was category A2-A3 (1.0 E+04 to 5.0 E+04 per m2). Stainlesssteel samples showed similar pattern only that in this case the sample exposed tochlorinated seawater showed a lesser pitting density.

Germanischer Lloyd stated in their evaluation that there were no significant differencesbetween the test samples exposed to natural seawater and treated seawater, either forcarbon or for stainless steel.

Crevice corrosion

Testing revealed no crevice corrosion for carbon steel, slight crevice corrosion for brass andcupro-nickel but it showed severe crevice corrosion effects on stainless steel, especially inuntreated seawater. Stainless steel samples immersed in chlorinated seawater showed lesssevere crevice corrosion than that of untreated seawater. All samples in untreated seawaterhad holes fully penetrated through the thickness of test coupons.

Coating assessment

Two epoxy-based ballast water tank coatings were assessed in accordance with ISO 4628and ISO 2624.


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After six months of exposure to 6 mg/L of NaOCl or untreated seawater, all samples with orwithout the cross-shaped scribe showed no degree of blistering. No defects were detectedunder 10-fold magnification. No cracking, flaking or delamination was found on any samples.

Cyclic potentiodynamic polarization measurement

The impact of chlorinated seawater on the stability of shipbuilding materials was investigatedby electrochemical measurements. These materials included stainless steel (SS316L),carbon steel (A36), brass (CDA 687) and copper-nickel alloy (CDA715). The polarizationmeasurements were carried out to determine the susceptibility of test specimens to localizedcorrosion in an environment with or without a presence of sodium hypochlorite (NaOClconcentrations of 0, 1, 2 and 6 mg/L). An indication of the susceptibility to initiation oflocalized corrosion in the test specimen is given by the potential at which the anodic currentincreases rapidly (denotes as ELC hereafter). The more noble this potential, the lesssusceptible the material is to initiation of localized corrosion.

Table 8.1.2-2: Short-term corrosion testing: evaluation of susceptibility oftest specimens to localized corrosion

Material Extent of LocalizedCorrosion

Stability against localized corrosion

Carbon Steel Low untreated & 1 mg/L > 2 mg/L > 6 mg/L

(-0.62 to -0.60 V) (-0.66 V) (-0.74 V)

Stainless steel High 1 mg/L & 2 mg/L > untreated > 6 mg/L

Aluminium Brass None N/A

Cupro-Nickel None N/A

Assessment

For the risk assessment, an operational scenario for a bulker with a round trip of 10 days isassumed. During the voyages, two complete ballast cycles are executed. As shown in theSiCURETM dossier for Basic Approval (IMO, 2008f) the concentration of Active Substancedecays within the first 24 hours to levels of about 0.5 to 0.7 mg/L where corrosion becomesinsignificant. Under this assumption and based on the laboratory testing, the effectivecorrosion rate of bare steel (after removal or damage to the coating system) in the ballasttank would result in a corrosion rate less than 0.082 mm/y (0.108 x 20%+0.075 x 80%). This

number when compared to the corrosion rate range given in The Tanker StructureCooperative Forum allows to make a conclusion that the effect that ballast water treated withthe SiCURE BWMS has on ballast water tanks is negligible.

8.1.3 Fire/explosion

As the SiCURE system does not require the storage of Active Substance on board, thereis no associated fire/explosion risk. The generation of sodium hypochlorite in situeliminatesthe need for chemical storage, however, it does result in the generation of hydrogen gas. Thesystem includes a degas tank with air blowers and hydrogen gas detecting instrumentation toensure that the hydrogen gas has been safely diluted with air prior to venting.


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8.1.4 Accidental chemical release

Under standard operations, the SiCURE system does not require the storage of anychemicals on board, therefore there is little associated risk of accidental chemical release.The generation of sodium hypochlorite in situ results in the generation of hydrogen gas.

Under normal operations, the generator cells do not leak or release any chemicals. Thesystem has built-in safety features that stops the system in case of leakage.

8.2 Risk to human health

This section discusses potential exposure pathways and risk to human populations whocould be exposed to chemicals associated with the SiCURE system. This sectionidentifies the chemicals that will be considered, discusses potential exposures to people whomay be affected, and discusses the potential of adverse health effects.

8.2.1 Identification of chemicals of potential concern and sources

The chemicals of potential concern (COPCs) related to the SiCURE system include theActive Substances, which are hypochlorous and hypobromous acids, and RelevantChemicals, which consist of trichloromethane, bromodichloromethane, bromochloroaceticacid, dibromochloromethane, tribromomethane, monochloroacetic acid, dichloroacetic acid,trichloroacetic acid, monobromoacetic acid, dibromoacetic acid, tribromoacetic acid, chlorate,bromated, dichloroacetonitrile, dibromoacetonitrile. The Relevant Chemicals may be formedin small amounts as disinfection by-products.

The Active Substances are produced in situand injected directly into the ballast water pipingsystem. The Relevant Chemicals are produced as by-products in the ballast water. There areno external sources of chemicals except sodium sulfite in case of the dechlorination option.

8.2.2 Exposure assessment

The Exposure Assessment consists of identifying human populations that could be exposedto COPCs, and the exposure pathways through which they could have contact with COPCs.A complete exposure pathway consists of:

- a source or chemical release from a source;

- an exposure point where contact can occur; and

- an exposure route by which contact can occur (such as ingestion, skin contact

or inhalation).

All of these components need to be present for a complete exposure pathway. This sectiondiscusses potential human populations who could be exposed to COPCs in the ballast water.

Potentially exposed human populations

On-deck personnel

During ballasting (uptake of ballast water to ballast tanks) it was assumed that the air in theheadspace of the ballast tank is released through air vents to the deck and that this air maycontain vapours of COPCs in the primary treatment water. Therefore, it was assumed that

on-deck personnel, including those involved in ship navigation, operation of ship machinery,maintenance activities, and resting crewmen in the ship's quarters, may be indirectlyexposed via inhalation of these vapours.


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The following general assumptions were used to estimate potential exposure and risk toon-deck personnel:

- ballasting occurs every two or three days (175 days/year);

- exposure of on-deck personnel only occurs during ballasting (maximumof 20 hours for large tanks); and

- on-deck personnel are assumed to have an occupational tenure of 6.6 years,based on the median occupational tenure of 6.6 years recommended for menand women 16 years and older in the U.S EPA's Exposure Factors Handbook(EPA, 1997)).

Tank inspector

Technicians would not be expected to contact COPCs under normal operations. In the

SiCURE system, Active Substances are injected directly into the ballast water piping system.The other COPCs would be formed as by-products in the ballast water. The potential forhuman exposure to concentrated levels of these COPCs would only exist during a failure ofthe system or when performing service/maintenance on the system. The risks associatedwith this scenario is mitigated by numerous system safeties (leak detection, purging of tank,equipment isolation, stray current protection, interlocks, etc.) and by using appropriatepersonal protective equipment when performing maintenance and/or repair on the system.

Under typical circumstances (when proper personal protective equipment is worn and theballast tank is properly ventilated prior to entry), there is only limited potential for significantexposure of this population because the tank is drained of its contents and purged of vapoursprior to entry and portable monitors are used to determine the condition of the atmosphere

while inside the ballast tank. However, for the purposes of this risk assessment, it wasassumed that several times during the year, a technician could be exposed to ballast waterduring visual inspection of the internal surface of all ballast tanks. The purpose of thisinspection is to check the soundness of the structure and the amount of sludge accumulatedin the ballast tanks. The visual inspection is to check the protective coating and look fordents and traces of corrosion. This inspection is normally conducted about twice a year inmany large shipping companies and, as such, a 6-month interval is assumed.

Exposure via inhalation of vapours that could potentially accumulate in the ballast tank andskin contact with the small quantity of water potentially remaining inside the ballast tank wasevaluated. The following general assumptions were made in estimating potential exposureand risk associated with this activity:

- the inspection of a ballast tank requires two hours;

- four tanks are inspected during each inspection event;

- two inspection events are conducted per year; and

- maintenance technicians are assumed to have an occupational tenureof 6.6 years, based on the median occupational tenure of 6.6 yearsrecommended for men and women 16 years and older in the U.S. EPA'sExposure Factors Handbook (EPA, 1997).


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Coast guard sampler

Boarding Coast Guard officers will measure the various parameters of ballast water (e.g., pH,TRC, salinity, turbidity, organic content, etc.) and collect water samples to assess if the shipis in compliance with ballast water treatment standards. To collect water samples, ballast

water is expected to be pumped into a collapsible tank from which samples are collected forbiological testing.

Exposure via inhalation of vapours in the breathing zone above the collapsible tank and skincontact with the ballast water during sampling was evaluated. The following generalassumptions were made in estimating potential risk associated with this activity:

- sampling of ballast tank requires one hour;

- twenty sampling events are conducted per month (240/year); and

- Coast Guards are assumed to have an occupational tenure of 20 years, based

on the median occupational tenure of 20.1 years for men and women 65 yearsand younger in the US EPA's Exposure Factors Handbook (EPA, 1997).

The large difference in the median occupational tenure used for the on-deck personnel/tankinspector and the Coast Guard is due to the significant variability in occupational tenureaccording to age and educational level. The strength of an individual's attachment to a specificoccupation has been attributed to the individual's investment in education (Carey, 1988 as citedin EPA, 1997). Workers with 5 or more years of college have the highest median occupationaltenure of 10.1 years. Sea tours in the Coast Guard are approximately 51 months (4 years);however, because Coast Guards receive specialized training/education, it is anticipated thatCoast Guard occupational tenure will likely be more lengthy than typical ship crews.

Passengers

Passengers would not be expected to contact COPCs under normal operations. Sincesodium hypochlorite is produced in situ, there is little potential for accidental chemicalrelease. There are numerous system safeties in place to mitigate a system failure. There islittle potential for this population group to be exposed directly to treated ballast water.Therefore, no complete exposure pathways were identified for this group.

Employees in harbours

Employees in harbours have little potential for exposure because of the low possibility ofaccidental release of sodium hypochlorite vapours and hydrogen gas. There is also littlepossibility for this group to be exposed directly to ballast water. Therefore, no completeexposure pathways were identified for this group.

Bathers

Bathers in the harbour areas could potentially be exposed to released ballast water. COPCconcentrations in ballast water would be greatly diluted in the seawater to which batherscould be exposed. Even though a complete exposure pathway exists for this group, there islittle possibility of adverse health effects since the COPC concentrations would be greatlydiluted when treated ballast water is released into the sea. In addition, as discussed insection 8.2.3, the measured ballast water concentrations of various chemicals were generally

lower than their respective drinking water guidelines. Therefore, no adverse health effectswould be expected from bathers who may occasionally be exposed to diluted concentrationsof these chemicals.


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Consumers of seafood

Consumers of seafood from the harbour area where the ballast water may be releasedare unlikely to be exposed to COPCs, since the COPCs are not expected to biomagnifyor bioaccumulate in seafood. The COPCs are not expected to exhibit biomagnifications

or bioaccumulations, and subsequently would not be expected to persist in the food web.The United Kingdom Department for Environment Food and Rural Affairs (DEFRA)defines a bioaccumulative chemical as having a log Kow greater than 4(http://www.defra.gov.uk/ENVIRONMENT/chemicals/csf/criteria/detailed.htm). The COPCsevaluated here all have log Kows less than 4. Therefore, no complete exposure pathwayswere identified for this population group.

Exposure concentrations

Pathways evaluated in this risk assessment included direct skin contact with ballast waterand inhalation of vapours from COPCs present in the ballast water. Incidental ingestion ofballast water is not reasonably expected to occur for any of the receptor exposure scenarios

evaluated. Therefore, ingestion of ballast water is not considered a complete exposurepathway. The methodology used to estimate exposure concentrations for the dermal contactand vapour inhalation pathways is presented below.

Direct dermal (skin) contact with ballast water

Because the chemical profile of the tank mixture changes with time, exposure needed to beevaluated assuming the chemicals were applied at two times: 1) the same day as theexposure (T0), and 2) five days prior to exposure (T5). For some COPCs, concentrations inwater were highest at T0 (trihalomethanes), while for others, the concentrations were highestat T5 (some haloacetic acids and haloacetonitriles). In addition, tests were conducted withfresh and brackish water. To streamline the assessment, the highest COPC concentration

measured in ballast water across all test conditions (i.e. T0 fresh water, T5 fresh water, T0brackish water, and T5 brackish water) was used in evaluating dermal (skin) contactexposure. Maximum measured ballast water concentrations are provided in Table 8.2.2-1.

Table 8.2.2-1: Maximum measured ballast water concentrations (g/L)

Chemical Fresh BrackishT0 T5 T0 T5

Trichloromethane 176 257 0.54 0.5Bromodichloromethane 14.9 19.4 4.2 5.3Dibromochloromethane 0.81 0.81 119.8 30.8Tribromomethane 0.5 0.5 119 268Monochloroaceticacid 5 2 17.8 2Dichloroaceticacid 60.3 77.5 1.3 1.3Trichloroaceticacid 107 99.9 1 1Bromochloroaceticacid 4.4 1 5.6 5.5Monobromoaceticacid 1 1 4.5 3.8Dibromoaceticacid 1 1 72.2 63.4Tribromoaceticacid 4 4 187 374Sodiumchlorate 450 440 370 380Sodiumbromate 50 50 50 50Dichloroacetonitrile 4.1 0.5 0.86 0.5Dibromoacetonitrile 0.5 0.5 28 29

NOTE: Detection limits were used for undetected chemicals, which is a conservative (health-protective) approach.


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Inhalation of vapours

Maximum vapour concentrations of COPCs present in ballast water were estimated for threeexposure scenarios:

- exposure of on-deck personnel due to a ballast vent;

- exposure of a tank inspector (inside ballast tank); and

- exposure of Coast Guard personnel during sampling and testing.

The estimation of emissions for each scenario was based on the maximum measured T0 andT5 concentrations provided in Table 8.2.2-1 for fresh ballast water and brackish ballast water.

8.2.3 Toxicity assessment

Adverse effects are generally classified as acute (short-term) or chronic (long-term). Chroniceffects are further subcategorized as carcinogenic or noncarcinogenic (i.e. potential effectsother than cancer).

Acute (short-term) evaluation

Acceptable levels for the evaluation of potential acute (1-hour) health effects were obtainedfrom the U.S. Department of Energy's (DOE's) current data set of Protective Action Criteria(PAC) values, which are available in an on-line searchable database athttp://www.atlintl.com/DOE/teels/teel.html. PACs may assume one of the following forms:

- Acute Exposure Guideline Levels (AEGLs);

- Emergency Response Planning Guidelines (ERPGs); and

- Temporary Emergency Exposure Limits (TEELs).

Chronic (long-term) evaluation

For purposes of this evaluation, acceptable levels for noncarcinogens assume one of thefollowing forms:

- United States Environmental Protection Agency (EPA, 2010) oral referencedose (RfD) in mg/kg-day;

- United States EPA (EPA, 2010) inhalation reference concentration (RfC) inmg/m3;

- World Health Organization (WHO, 2006) oral tolerable daily intake (TDI) inmg/kg-day; or

- WHO (WHO, 2006) total allowable concentration (TAC) in mg/m3.

For the purposes of this risk assessment, the threshold effects levels were assumed to equalthe internal dose level that corresponds to a cancer risk of 1 x 10-5 and were derived from thefollowing sources:


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- United States EPA dermal unit risk factor in mg/kg-day (these values werecalculated using the oral slope factor due to the lack of dermal toxicity values);

- United States EPA Risk-Specific Air Concentration (RSC) in mg/m3;

- WHO oral cancer risk (CR) in mg/kg-day; or

- WHO inhalation CR in mg/m3.

The 1 x 10-5 target cancer risk represents the mid-point of the cancer risk range targeted bymost authoritative organizations. Use of the 1 x 10-5 target cancer risk for establishingacceptable levels corresponds with the German screening levels established under theBundes-Bodenschutz und Altlastenverordnung (BBodSchV), which stands for FederalGround Protection and Refuse Dump Regulations. Many other internationally-recognizedregulatory bodies, such as the WHO also use this target cancer risk for establishingscreening values. Thus, a target cancer risk level of 1 x 10-5 was used to derive risk-specific

doses for carcinogens, expressed in units of mg/kg-day. Oral and inhalation referencedoses, also expressed in units of mg/kg-day, were used to evaluate COPCs with potentialnoncarcinogenic effects.

8.2.4 Risk characterization

Risk characterization is the process by which the toxicity information is integrated withquantitative estimates of human exposure derived in the exposure assessment. A riskcharacterization ratio (RCR) or margin of safety (MOS) for each of the COPCs wascalculated as follows:

MOS = Acceptable Level/Exposure Level

Where:

Acceptable Level = Protective Action Criteria (PAC) for the acute(short-term) evaluation and for the chronic (long-term)evaluation, a threshold level for noncarcinogens orconcentration level that corresponds to a cancer riskof 1 x 10-5 (see above) for carcinogens

Exposure Level = Absorbed dose based on predicted concentration inballast water (mg/L) or air (mg/m3)

For purposes of this risk assessment, a MOS of one (1) or greater was judged to indicatethere is no unacceptable risk. Detailed exposure and MOS calculations are provided inappendix G/attachment 2. Working spreadsheets will be provided upon request.

Acute risk

Maximum modelled 1-hour air concentrations were compared to PACs to determine theacute MOS for inhalation exposures. The results of those comparisons are provided inTable 9 of appendix G/attachment 1. As can be seen in Table 9 of attachment 1, the 1-hourconcentrations for all COPCs were less than their corresponding PACs, resulting in an acuteMOS of greater than one for all COPCs. In fact, as summarized in Table 8.2.2-3, thepredicted 1-hour concentrations ranged from one to 29 orders of magnitude lower than the

corresponding PACs, indicating that potential risks from short-term inhalation exposures arevery low.


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Table 8.2.4-1: Acute margins of safety

Chemical OnDeckPersonnel CoastGuard TankInspector2mVent 3mVent

Trichloromethane 53 1170 45,600 35,500Bromodichlo

ballast water management system submitted by germany ( imo )

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