Health-Related Components of DSL Health-Related Components of DSL Categorization under CEPA 1999Categorization under CEPA 1999

Exposure and Hazard ToolsExposure and Hazard ToolsPresented by: Presented by:

JesseJesse Ng NgExisting SubstancesExisting Substances Division Division

Health CanadaHealth Canada

Oct 20, 2005Oct 20, 2005

2

Outline

• The Canadian Environmental Protection Act• Health Canada’s mandate• Categorization

– Principles and objectives• Maximal List• Exposure Tools• Hazard Tools• Input from stakeholders• Screening Assessments• Key messages

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Existing Substances under the Canadian Environmental Protection Act (CEPA)• CEPA is administered jointly by Environment Canada and

Health Canada• CEPA 1999 – extended our mandate from Priority

Substances to Categorization of the approximately 23,000 existing substances on the Domestic Substances List (DSL) by September 2006

• The DSL was created for the purpose of defining a “new substance” under CEPA

• Includes substances “grandfathered” under the legislation • Substances in use between January 1, 1984 and

December 31, 1986 • Organics (50%), organic metal salts, organometallics,

inorganics, polymers and substances of unknown or variable composition, complex reaction products & biological materials (UVCBs)

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Health Canada’s Mandate on Existing Substances

• Address both exposure and effects to set priorities for risk assessment and management under CEPA

• Source characterizations to inform risk management

– Information Gathering/Industrial Surveys

• Publicly accountable – transparent process and content, peer input, consultation and review, documented outcome

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Categorization – human health

Need to consider:

• “Greatest potential for exposure” (GPE) – all DSL substances• “Inherently Toxic to humans” (IThuman) – subset of substances

[Those that are P or B [but not inherently toxic to environmental organisms (ITeco)]

Challenges:

• Categorization must be completed by September 2006• Consistency with Priority Substances outcomes for high hazard

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CATEGORIZATION of the Domestic Substances List (DSL) (First Phase) (n=23,000)

Decisions of Other

Jurisdictions

Public Nominations

No further action under this program

CEPA-Toxic

No further action under this program

CEPA-Toxic

IN-DEPTH ASSESSMENT Priority Substances List (Third Phase)

Risk Management

Risk Management

Greatest Potentialfor Human Exposure

Substances that are Persistent or Bioaccumulative

“Inherently Toxic”to Humans

“Inherently Toxic” tonon-Human Organisms

SCREENING ASSESSMENT (Second Phase)

STAGE 1

STAGE 2

STAGE N-1

STAGE N

STAGE 3

CEPA Existing Substances Program

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Categorization Objectives

• Set priorities for data generation and health assessment for all Existing Substances

• Health protective approach, conservative in the absence of information

• Complex program architecture requires multiple stages of increasing complexity which address all groups of compounds concomitantly– First stages: simple/pragmatic to address all

substances, based on limited information for each or many

• Simple tools– Subsequent stages must be discriminating to set true

priorities for further work• Complex tools

• Avoid continuing bias to focus on data-rich Existing Substances

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Identifying Highest Priorities for Human Health Approach

• Initial application of simple, discriminating tool on exposure to address all 23,000 substances to prioritize “Greatest Potential for Exposure” (GPE), “Intermediate Potential for Exposure” (IPE) & “Lowest Potential for Exposure” (LPE)– Draws on information submitted in compilation of the Domestic

Substances List

• Application of simple, discriminating tool to address hazard for all 23,000 substances– Draws on work completed internationally

• Priority-based application of more complex tools to additionally refine & prioritize

DOMESTIC SUBSTANCES LIST

Substances that are Persistent and/or Bioaccumulative According to the Regulations

Organic Substances that are Persistent and/or

Bioaccumulative and Not “Inherently Toxic” to Non-

human Organisms

Substances that are Persistent and/or Bioaccumulative and

“Inherently Toxic” to Non-human Organisms

ENVIRONMENT CANADA

No Further Action(Not 64c “toxic”)

INTEGRATED FRAMEWORK

Highest

Lowest

HEALTH CANADA

DSL Substances Identified as Hazardous to Human

HealthDSL Substances Ranked

According to Potential

For Exposure

HC Maximal List

EC Substances Identified forScreening Assessment

Substances Prioritized & IdentifiedFor Full Screening Health Assessment

Application of Complex Tools

Application of Simple Tools

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The Maximal List

High 576

Moderate 989

Low 331

301 LPE, High Hazard

275 GPE or IPE & High Hazard

121 IPE, P or B

480 GPE

388 IPE, P or B unknown

183 Low Hazard

148 “other”

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What Do the Groups on the Maximal List Mean?

• High likelihood of remaining for further work beyond 2006– Subset of 301 for risk management (LPE & high hazard)

• Moderate likelihood of remaining as health priorities beyond 2006– Information will help here

• UVCBs, polymers, wide range use substances delineated as priorities

• Low likelihood of remaining for further work beyond 2006– Low hazard – Substances already addressed CEPA

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DSL TOOLS - HEALTH

Exposure

• SimET (Relative ranking of all DSL substances based on submitters (S),quantity (Q) and expert ranked use (ERU)

• ComET (Quantitative plausible maximum age-specific estimates of environmental and consumer exposure for individuals based on use scenario (sentinel products), phys/chem properties & bioavailability)

Hazard Quantification (Previously Exposure-Response)

• HazQ (measures of exposure-response developed (where possible) on the basis of measured or predicted carcinogenic potency, reference values or effect levels

Hazard [High (H) or Low (L)]

• SimHaz (identification of high or low hazard compounds by various agencies based on weight of evidence)

• ComHaz (Hierarchical approach for multiple endpoints & data sources (e.g., QSAR) including weight of evidence

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Simple Exposure Tool - SimET

• SimET is a relative ranking tool by which we have “binned” all substances on the DSL– Considers potential for environmental and

consumer exposure• Based on three different lines of evidence, derived

from the limited information provided for all substances on the DSL:– quantity (estimated annual quantity of use,

Q),– number of submitters, S– use (sum of normalized expert ranked use

codes, U), reflecting two workshops• Industrial sector and functional use codes

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Criteria for Greatest, Intermediate and Lowest Potential for Exposure (GPE, IPE & LPE)

Quantity (kg/year)

Number of Submitters

Sum of the Expert Ranked Use Code Indices

GPE > 100 000 Top 10% Top 10%

IPE > 10 000 n.a. Top 30%

LPE All All All

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• Provides quantitative plausible maximum estimates of exposure of individuals in the general population by age group for consumer (near-field) & multimedia environmental (far-field) exposure

• Far-field exposure– Based on concentrations in environmental media

estimated from fugacity modelling

• Near-field exposure– Frequency and duration of product use – Based on “Sentinel” product scenarios

• Exposure for all age groups to be addressed

The Complex Exposure Tool (ComET)

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Chemical Identity

Physical/ChemicalProperties

Substance Profile

ProductionQuantity

Measures of Dose-Response for Critical Effects

Priority for Assessment

Production Quantity Bin

+Release Factor

Emissions

Near-field Far-field

Human Exposure

Sentinel Products

SP1 SP2 SP3 SPn

Far Field

Age Specific

Variables

Overview of ComET

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Principles in Developing ComET

• Transparency in the approach and assumptions– Uncertainties and data gaps identified

• Defensibility, Consistency and Inclusiveness– Drawing maximally on the documented work of others

by building on existing scenarios • Data call in to stakeholders• Peer input, consultation and review• Outreach to other jurisdictions

• Fit for purpose– Conservative and protective assumptions for priority

setting, but adaptable to enable incorporation of more refined models

• Readily useable and applicable to all chemicals irrespective of data available– Drawing maximally on generic information

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ComET – Far-field

Exposure from DSL substances in the environment

• Extension of existing fugacity models (e.g., ChemCAN) to estimate concentrations of substances in environmental media (Mackay model)

– Physical/Chemical properties– Emissions/Releases– Distribution of substances into relevant media, e.g., air, water,

soil, sediment– Fate, e.g., drinking water, foodweb

• Generic unit world model that can be scaled and modified for further refinement

• Applied to substances for which little or no empirical property data are available and emission rates are known only approximately

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Substance

Calculate Unit Emissions

Ambient Concentrations

Integrate with Near-field Component

The Far-field Model

Scale unit concentrations using actual emissions,production quantities and use information

Phys-Chem properties and use information(Substance Profile)

Transformationand fate

Migration into mediafor uptake

Route of exposure

Estimated intake (μg/kg-bw per day) of (name of substance from DSL) by various age groups

0–6 months

0.5–4 years

5–11 years

12–19 years

20–59 years

60+ yearsformula

fed

not formula

fed

Ambient air

Indoor air

Drinking water

Food and beverages

Soil

Total intake

Far-field - Output

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ComET – Near-field

Exposure from DSL substances in consumer products

• Selection of “sentinel” products– Identification of use of a substance for a specific function in a

product (e.g., surfactant in paint, solvent in paint, pigment in paint)

– Physical/Chemical properties– Bioavailability

• Sentinel Product Scenario– Contains elements of exposure, i.e., exposure factors

• Maximum proportion generically used for a specific function in a product (e.g., % of surfactant in paint, etc.)

• Frequency and duration of product use• Amount transferred during use• Age-specific personal factors

• Designed to provide a reasonable worst-case estimate of exposure

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“Sentinel” Product (SP)

• A sentinel product is a specific type of consumer product with a defined composition and use that yields the highest exposure to an individual for one of its component substances as compared to other consumer products containing that substance

• Sentinel products are selected from broader classes, e.g. personal care products

• A specific substance is then matched to one or more sentinel product(s) based on generic information about its use pattern

e.g. for acetone, possible SPs are:• nail preparations• acrylic paints

• There may be more than one SP for a given substance

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• Product categories generally accepted to represent high exposure potentials:

– Household cleaning products– Soaps and detergents– Cosmetics and personal care products– Food additives– Fabric treatments– Paints and coatings– Adhesives and sealants– Hobby and craft products– Automotive care and maintenance products– Lubricants– Fuels and solvents– Lawn and garden care products

Considerations for selection of Sentinel Products

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Scenarios for Sentinel Products

• Routes of exposure (oral, dermal, inhalation) determine how scenarios are developed

• Information gathering:– In-house contracts, surveys, e.g., CEPA sect. 71– MSDS, e.g., CCOHS, NIOSH– Public sources, e.g., Scorecard, Household Product Database,

etc.– Industry input, e.g., Soap and Detergent Association (SDA)

• Appropriate algorithms are selected from an exposure matrix including ComET and other publicly available models (e.g., ConsExpo, ECETOC TRA, CEM, etc.)

• Appropriate conservative exposure factors are used to populate the algorithms (e.g., Versar, SDA, etc.)

• ComET contains ~146 different Sentinel Products scenarios, each of which contains one or more exposure route(s)

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Scenario Algorithm - Example

Inhalation

ED = WF x A x ET x IR x EF BW x RV x AT

whereED = estimated dose per event (mg/kg-bw perday)WF = weight fraction of substance in productA = amount of product used per event (mg)ET = exposure time (i.e., duration of exposure) (h)EF = Exposure frequency (unitless)IR = inhalation rate (m3/h)BW = body weight (kg-bw)RV = room volume (m3)AT = Averaging time (day)

Age-specific variables}

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ComET output – Near-field exposure

• When a substance occurs in more than one product or is described by more than one use code, ComET will provide an estimate of either:– Sum of doses or highest dose

• Estimate values for any of the different types of exposure:– Acute, sub chronic, or chronic;– Any of the six age groups;– Any of the three route specific exposures or

the total dose

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ComET – Next Steps

• Completion of taxonomy of sentinel products and algorithms for sentinel products

• Solicit input/information/comment on the architecture, and data to populate for decision making– Availability of habit and use surveys– Example: SDA Document exposure and risk screening

methods for consumer product ingredients

• Peer review of taxonomy, algorithms and default values– Need for adequate documentation as a basis for default

parameters in the algorithms and selection of sentinel products

– Public availability of habit and use survey information– Consistency with well documented sources– Process – peer input, consultation, review

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Exposure Tools

Phase• Categorization

• Screening Assessments

• In-depth Assessments -Priority Substances

ToolSimple Exposure Tool

Complex Exposure Tool

Consumer exposure scenarios/algorithms

Consumer Exposure Models– WPEM (wall paint exposure (wall paint exposure

model)model),– CEM (consumer

exposure module, E-Fast),

– ConsExpo

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DSL TOOLS - HEALTH

Exposure

• SimET (Relative ranking of all DSL substances based on submitters (S),quantity (Q) and expert ranked use (ERU)

• ComET (Quantitative plausible maximum age-specific estimates of environmental and consumer exposure for individuals based on use scenario (sentinel products), phys/chem properties & bioavailability)

Hazard Quantification (Previously Exposure-Response)

• HazQ (measures of exposure-response developed (where possible) on the basis of measured or predicted carcinogenic potency, reference values or effect levels

Hazard [High (H) or Low (L)]

• SimHaz (identification of high or low hazard compounds by various agencies based on weight of evidence)

• ComHaz (Hierarchical approach for multiple endpoints & data sources (e.g., QSAR) including weight of evidence

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SimHaz Tool

• Applied to entire DSL• Defines high or low hazard from

classifications/assessments of other agencies based on weight of evidence

• Appropriate assessments selected based on comprehensiveness of review, peer review process, etc.

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SimHaz Tool

• Endpoints chosen based on general population concerns

• High Hazard Lists/Endpoints– Cancer (IARC, EU, HC, US EPA etc.)– Genotoxicity (EU)– Developmental Toxicity (EU)– Reproductive Toxicity (EU)

• Low Hazard Lists– PMRA 4a/US EPA– OECD Low Concern

• Respiratory sensitization endpoint – dropped from SimHaz as more relevant to occupational exposure

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SimHaz ToolStrengths and Limitations

• Strengths– Efficient

• Takes advantage of critical review of others

– Consistency • Assessments/classifications internationally

• Limitations– Bias towards data-rich substances

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ComHaz Tool

• Hierarchical approach for multiple endpoints & data sources, including limited weight of evidence, for identifying compounds for further consideration.- Qualitative and/or quantitative criteria developed for various endpoints. - Conservative so that confidence is high that substances that are not considered priorities for further consideration based on any of the criteria are non hazardous. - For qualitative endpoints, weight of evidence is assessed, where possible.

• Currently, confidence in predictive tools only for cancer/genotoxicity

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Complex Hazard (ComHaz) Tool

CHEMICAL X

REPRODUCTIVETOXICITY?

CARCINOGENICITY?

GENOTOXICITY?

DEVELOPMENTALTOXICITY?

LONGER TERMTOXICITY?

SHORT TERMTOXICITY?

ACUTETOXICITY?

REFERENCE / REGULATORYVALUES

WEIGHT OF EVIDENCE FOR

GENOTOXIC CARCINOGENICITY?

EX

PO

SU

RE

-RE

SP

ON

SE

(H

AZ

AR

DQ

UA

NT

IFIC

AT

ION

)

SE

T A

SID

E F

RO

M F

UR

TH

ER

CO

NS

IDE

RA

TIO

N A

T T

HIS

TIM

E

MEETS CRITERIA

MEETS CRITERIA

MEETS CRITERIA

MEETS CRITERIA

MEETS CRITERIA

MEETS CRITERIA

MEETS CRITERIA

YES

DOES NOT MEET CRITERIAOR INSUFFICIENT DATA

DOES NOT MEET CRITERIAOR INSUFFICIENT DATA

DOES NOT MEET CRITERIAOR INSUFFICIENT DATA

DOES NOT MEET CRITERIA

INSUFFICIENTDATA

INSUFFICIENTDATA

DOES NOT MEET CRITERIA

DOES NOT MEET CRITERIA

DOES NOT MEET CRITERIAMEETS

CRITERIA

NO

INSUFFICIENT DATA

CHEMICAL X

REPRODUC TIVETOXI CI TY ?

CARCINOGENICI TY ?

GEN OTOXICI TY?

DEVELOP ME NTALTOXI CI TY ?

LONGE R TERMTOXI CI TY ?

SHORT TE RMTOXI CI TY ?

ACU TETOXI CI TY ?

REFERENCE / R EGULATOR YVALUES

WEIGH T OF EVIDENCE FOR

GEN OTOXIC CARCINOGENICI TY ?

HA

ZA

RD

Q

UA

NT

IFIC

AT

ION

(E

XP

OS

UR

E-R

ES

PO

NS

E)

SET

AS

ID

E F

RO

M F

UR

TH

ER

CO

NS

IDE

RA

TIO

N A

T T

HIS

TIM

E

MEETS CRITERIA

MEETS CRITERIA

MEETS CRITERIA

MEETS CRITERIA

MEETS CRITERIA

MEETS CRITERIA

MEETS CRITERIA

YES

DOES N OT MEET CRITERIAOR INS UFFICIENT DATA

DOES NOT MEET CRITERIAOR INSUFFICIENT DATA

DOES NOT MEET CRITERIAOR INSUFFICIENT DATA

DOES NOT MEET CRITERIA

INSUFFICIENTDATA

INSUFFICIENTDATA

DOES NOT MEET CRITERIA

DOES NOT MEET CRITERIA

DOES NOT MEET CRITERIAMEETS

CRITERIA

NO

INSUFFICIENT DATA

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ComHaz Tool

• Sources of Information – Comprehensive literature searching (electronic &

hardcopy resources)– Reviews or secondary accounts of toxicological

or epidemiological studies– Original Toxicological and Epidemiological

Studies– [(Quantitative) Structure Activity Relationship

(QSAR)]Models (TOPKAT, CASETOX)– Chemical structures of concern, Structure

Activity Relationship (SAR) models (DEREK), surrogate/analogue approaches (Leadscope)

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ComHaz Tool

• Qualitative criteria– Cancer– Genotoxicity– Developmental toxicity

• Quantitative criteria– Regulatory/reference values– Developmental toxicity– Reproductive toxicity– Long term toxicity– Shorter term toxicity– Acute toxicity

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ComHaz Tool – Criteria

Endpoint Information Source Criteria

Cancer Data or (Q)SAR Weight of evidence

Genotoxicity Data or (Q)SAR Weight of evidence

Regulatory/Reference Value

International & National Assessments

Ref Value ≤ 0.1 mg/kg bw/day ≤ 0.4 mg/m³

Developmental Toxicity Data NO(A)EL ≤ 90 mg/kg bw/dayNO(A)EC ≤ 270 mg/m³

(Q)SAR Positive Prediction

Reproductive Toxicity Data NO(A)EL ≤ 10 mg/kg bw/dayNO(A)EC ≤ 30 mg/m³

Longer Term Toxicity Data or (Q)SAR (where appropriate)

NO(A)EL ≤ 10 mg/kg bw/dayNO(A)EC ≤ 30 mg/m³

Short Term Toxicity Data NO(A)EL ≤ 30 mg/kg bw/dayNO(A)EC ≤ 90 mg/m³

Acute Toxicity Data or (Q)SAR (where appropriate)

LD50 ≤ 500 mg/kg bw

LC50 ≤ 1500 mg/m³

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ComHaz ToolPreliminary Weight of Evidence (WoE) Framework

Why Cancer/Genotoxicity?

• ComHaz endpoints for which capture rate is highest– Qualitative ComHaz criteria are very conservative

(i.e., first hit)– Need to increase discrimination to identify priorities

for further consideration • Confidence in (Q)SAR greatest for these endpoints

– Larger more diverse training sets (e.g., simple screening assays such as Ames test)

– Potential for combining relevant endpoints– Relevance to specific modes of action

• Genotoxic carcinogenicity is critical endpoint for more in-depth assessments (i.e., screening/PSL)

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Preliminary WoE FrameworkDevelopment Process

• Draft approach developed• Acquired operational experience through

consideration of individual compounds• Continued to revise approach based on this

experience as well as internal and external consultation– Internal consultation with genotox

specialists– External peer consultation (www.tera.org)

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Preliminary WoE FrameworkPrinciples/Approach

• Separate consideration of endpoints: Carcinogenicity; Genotoxicity

• Separate consideration of lines of evidence:– Empirical data, QSAR, SAR

• For (Q)SAR models, output is weighted based on predictive power of both the assays and validation results for similar compounds.

• Equivocal data/inconclusive predictions noted, but not weighted

• “Call” for a line of evidence based on consideration of ratio of positives/negatives and degree of confidence

• Degree of confidence based on consistency between data and predictions

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Preliminary WoE Framework

(Q)SAR Models

CARCINOGENICITY

GENOTOXICITY

CASETOX(version 1.56)(Multicase PC Version)

DEREK FOR WINDOWS(version 8.0.1)

TOPKAT(version 6.2)

TOPKAT(version 6.2)

CASETOX(version 1.56)(Multicase PC Version)

DEREK FOR WINDOWS(version 8.0.1)

•NTP Carcinogenicity•Male Rat (version 3.2)•Female Rat (version 3.2)•Male Mouse (version 3.2)•Female Mouse (version 3.2)

•NTP Rodent Carcinogenicity (A07)•FDA-CDER Rodent Carcinogenicity (non-proprietary)

•Male Rat (AF1)•Female Rat (AF2)•Male Mouse (AF3)•Female Mouse (AF4)

• 49 Structural Alerts for Carcinogenicity

•Ames Mutagenicity (version 3.1)

• Salmonella Mutagencity (A2I)•Somatic Mutations in Drosophila (A2D)•Mutations in Mouse Lymphoma Cells In Vitro (A2F)•Chromosomal Aberrations in CHO cells In Vitro (A61)•Induction of Micronuclei in Mouse Bone Marrow In Vivo (A62)•Unscheduled DNA Synthesis in Rat Hepatocytes In Vitro (A64)•Aneuploidy in Yeast (A6A)

• 97 Structural Alerts for Genotoxicity

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Preliminary WoE Framework

OutcomesCHEMICAL X

From Moderate Group of Maximal

List

Positive carcinogenicity study or QSAR prediction

Positive genotoxicity study or QSAR prediction?

Meets criteria for remaining quantitative endpoints in

Hierarchical Approach?

WoE Cancer/GenetoxHigh Potential for

Genotoxic Carcinogenicity?

Next Step: Hazard Quantification Tool(Exposure-Response Characterization)

SET ASIDE

NO

NO

NO

NO YES

YES

YES

YES

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ComHaz ToolProcess – Development/Testing

• Considerable internal operational experience• External testing for consistency of output

based on search strategy/approach• External peer review of internal/external

consistency of critical aspects of approach• Internal QA/QC• Expert consultation

– e.g., genotoxicity, WoE

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ComHaz ToolStrengths and Limitations

• Strengths– Health protective– Comprehensive– High confidence in “set asides”– No bias towards data rich substances– Designed for high throughput– Takes advantage of critical reviews of others– Significant contribution of QSAR component to

international priority setting– External input, consultation, peer review

• Limitations– Resource intensive

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Hazard Quantification Tool (Previously called Exposure-Response Tool)

• Developed from a Toxicity Profile– For compounds that are ComHaz IN– All toxicological endpoints considered (i.e.,

carcinogenicity, developmental, reproductive, acute, etc.)

– For each endpoint, the Quantified Hazard (carcinogenic potential, NOEL/LOEL, etc) is determined for various durations of exposure

– Available data on pharmacokinetics, mode of action and species specificity are also considered

– Informs as to what type of Screening Model will be proposed for compound (ie. Various screening assessment models are being drafted; in some cases, input from Exposure Tools will be required).

– Toxicity Profile and Tool still in development

46

Hazard Tools

Phase• Categorization

• Screening Assessments

• In-depth Assessments -Priority Substances

ToolSimple Hazard Tool (SimHaz)

high and low hazardComplex Hazard Tool

first stage QSAR/SAR WoE (if needed)

Exposure-Response (Hazard Quantification)Tool

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Input from Stakeholders

• 60-day comment period on the Proposed Integrated Framework for the Health-Related Components of DSL categorization ended August 30, 2005.

• Data requested on DSL compounds, especially those on the Maximal List, Deadline for submission was Sept. 16, 2005.

• Responses received from Industry– e.g., ACC, ATOFINA, BASF, CPMA, Degussa, Nova

Chemicals

• Input from Environmental Non-Governmental Organizations

48

Screening Assessments

• Need to assess more compounds more quickly• No legislated deadlines, however high

expectations• Draw on international/assessments to extent

possible and considerable collective experience in HC and limited external peer review

• Consistent with principles of in-depth PSL assessments

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Full Focused Screening Assessments• Decisions based on consideration of:

– Nature of critical effect– Margin between critical effect level and upper

bounding estimate of exposure– Adequacy of margin to account for

uncertainties in database• Possible outcomes:

– Not “toxic” under CEPA 1999– Further in-depth assessment required– “Toxic” under CEPA 1999

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Screening Assessments - Status

• Public comments received on: PBDEs & PFOS

• Screening Health Assessments to be released on our Listserv:

QuinolineMBMBP MBOCA1,2-Dibromoethane 1,1-DichloroetheneBiphenyl Ethylbenzene

DNOC Hexachloroethane

51IN-DEPTH ASSESSMENT-Priority Substances ListIN-DEPTH ASSESSMENT-Priority Substances List

FOCUSED SCREENING ASSESSMENT FOCUSED SCREENING ASSESSMENT

Use and Emission Profiling; Current

Control Measures

Toxicity Profiling of Effects and other

Related Data+

Substance Profile and Issues Flagged

Not a priority for further consideration

Prioritized for further consideration

Issue Identification

CEPA-ToxicNo further action under this program

Substances Prioritized for further consideration from CategorizationPhase I

Phase II

Phase III

52

• Framework developed to identify true priorities from a human health perspective.– takes into account both exposure and hazard.

• Series of simple and complex “tools” developed.– exposure assessment and hazard identification.

• Tools applied in identification and prioritization of substances for assessment.– also as part of the health risk assessment process

itself.

• Innovative and ensures efficient assessment to meet CEPA 1999 mandate.

Key Messages

53

More Information?

• Health Canada Existing Substances Division Website – http://www.hc-sc.gc.ca/ewh-semt/contaminants/existsub/index_e.html

• Health Canada Maximal List and Integrated Proposal Framework – http://www.hc-sc.gc.ca/ewh-semt/contaminants/existsub/framework-cadre_e.html

• Health Canada Existing Substances Mailing List – http://www.hc-sc.gc.ca/ewh-semt/contaminants/existsub/mail-avis_e.html

• CEPA Registry – http://www.ec.gc.ca/CEPARegistry/default.cfm