Water Chemistry and Water Chemistry and PollutionPollution

Why we measure water quality?Why we measure water quality? When a body of When a body of

water is overfed water is overfed with nutrients it with nutrients it can create massive can create massive algal blooms which algal blooms which causes very low causes very low levels of DO killing levels of DO killing off many aquatic off many aquatic organisms.organisms.

www.thebutlerchain.com/www.thebutlerchain.com/introduction.htmintroduction.htm

PfiesteriaPfiesteria

Found in waters high in nutrientsFound in waters high in nutrients

-Harmful Algal Bloom (HABs)-Harmful Algal Bloom (HABs)

www.sierraclub.org

A fertilized lake A fertilized lake designated "Lake 227" designated "Lake 227" in northwest Ontario, in northwest Ontario, Canada, (foreground) Canada, (foreground) with increased algae, with increased algae, whose growth has been whose growth has been found unpredictable, found unpredictable, pictured next to a lake pictured next to a lake that hasn't been that hasn't been manipulated for manipulated for research. (Photo by research. (Photo by Karen J. Scott Karen J. Scott www.monitor.netwww.monitor.net))

Would you want to swim at Would you want to swim at this beach?this beach?

““Under the belief that water Under the belief that water could dilute any substance, could dilute any substance, industries and individuals industries and individuals during the 18th and 19th during the 18th and 19th centuries often used rivers centuries often used rivers and lakes as garbage cans. and lakes as garbage cans. Industrial effluent, raw Industrial effluent, raw sewage and animal carcasses sewage and animal carcasses would often be dumped into would often be dumped into waterways, without much waterways, without much thought of contamination and thought of contamination and downstream neighbors.” downstream neighbors.”

http://www.great-lakes.net/teach/pollution/water/water2.htmlhttp://www.great-lakes.net/teach/pollution/water/water2.html

EutrophicationEutrophication

Excessive Nutrients: N>3ppm P>.01ppmExcessive Nutrients: N>3ppm P>.01ppm Causes excessive growth of marine Causes excessive growth of marine

autotrophs (large algal blooms)autotrophs (large algal blooms) Die off of Marine Plants = Lack of LightDie off of Marine Plants = Lack of Light Decomposition of marine plants uses more Decomposition of marine plants uses more

oxygen which can lead to an “oxygen sag” oxygen which can lead to an “oxygen sag” in an aquatic environmentin an aquatic environment

The Dead ZoneThe Dead Zone

Oxygen minimum zone that develops Oxygen minimum zone that develops annually in response to nutrient and other annually in response to nutrient and other inputs to the Gulf of Mexico. inputs to the Gulf of Mexico.

Hypoxic - <2.0mg/l of dissolved oxygen Hypoxic - <2.0mg/l of dissolved oxygen Anoxic – 0.0mg/l of dissolved oxygenAnoxic – 0.0mg/l of dissolved oxygen

To determine the health of a body of To determine the health of a body of water, many parameters or guidelines are water, many parameters or guidelines are monitored includingmonitored including

Coliform Bacteria, Dissolved Oxygen Coliform Bacteria, Dissolved Oxygen (DO), Nitrate/Nitrite, Phosphate, pH, (DO), Nitrate/Nitrite, Phosphate, pH, Temperature, & TurbidityTemperature, & Turbidity

Coliform BacteriaColiform Bacteria

EPA standards: EPA standards: One coliform colony / I00 mL of One coliform colony / I00 mL of water is cause for concernwater is cause for concern

Four colonies per 100 mL requires direct actionFour colonies per 100 mL requires direct action The appearance of The appearance of coliform bacteriacoliform bacteria indicates the indicates the

presence of raw sewage. Raw sewage may contain presence of raw sewage. Raw sewage may contain disease-producing bacteria.disease-producing bacteria.

Coliform is an indicator species.Coliform is an indicator species. A coliform test measures the amount of A coliform test measures the amount of E. coli E. coli

present in the water supplypresent in the water supply

Dissolved OxygenDissolved Oxygen

DO is dependent on a DO is dependent on a number of factors number of factors including salinity, including salinity, temperature, temperature, photosynthesis rates photosynthesis rates atmospheric atmospheric pressure, and the pressure, and the amount of wind & amount of wind & wave turbulence.wave turbulence.

The suitability of a body The suitability of a body of water for organisms to of water for organisms to live can be determined by live can be determined by the amount of DO in the the amount of DO in the water.water.

Fish require 4-5 mg Fish require 4-5 mg OO22/liter of water while air /liter of water while air

breathing aquatic breathing aquatic organisms require less.organisms require less.

Nitrates/NitritesNitrates/Nitrites

EPA standards: Nitrate EPA standards: Nitrate cannot exceed 10 mg/Lcannot exceed 10 mg/L

Excess levels of nitrates Excess levels of nitrates can cause hypoxia. can cause hypoxia.

Excess nitrite can cause Excess nitrite can cause the “blue baby syndrome” the “blue baby syndrome” and is toxic to warm-and is toxic to warm-blooded organisms.blooded organisms.

Natural levels of nitrates Natural levels of nitrates in surface water is in surface water is <1mg/L.<1mg/L.

Essential nutrient for Essential nutrient for plants & animals.plants & animals.

Sources of nitrates come Sources of nitrates come from the atmosphere from the atmosphere (automobile exhaust), (automobile exhaust), fertilizer runoff from land, fertilizer runoff from land, animal excrement, animal excrement, sewage wastes, and plant sewage wastes, and plant debris. debris.

Wastewater treatment Wastewater treatment plants can have nitrate plants can have nitrate levels as high as 30mg/L. levels as high as 30mg/L.

PhosphatesPhosphates

Phosphorus is also an essential nutrient for the plants Phosphorus is also an essential nutrient for the plants and animals that make up the aquatic food web.and animals that make up the aquatic food web.

Phosphorus is naturally available in low concentrations Phosphorus is naturally available in low concentrations and is often limited.and is often limited.

Small increases can result in accelerated plant growth, Small increases can result in accelerated plant growth, algae blooms, low dissolved oxygen, and the death of algae blooms, low dissolved oxygen, and the death of certain fish, and other aquatic animals.certain fish, and other aquatic animals.

Sources of phosphorus include Sources of phosphorus include soil and rocks, soil and rocks, wastewater treatment, fertilizer runoff, failing septic wastewater treatment, fertilizer runoff, failing septic systems, runoff from animal manure, disturbed land systems, runoff from animal manure, disturbed land areas, drained wetlands, and commercial cleaning areas, drained wetlands, and commercial cleaning preparations.preparations.

pHpH pH describes how pH describes how acidicacidic or or alkalinealkaline a substance is. a substance is.

Acidity increases as the pH gets lower (pH of 7 being Acidity increases as the pH gets lower (pH of 7 being neutral).neutral).

pH affects many chemical and biological processes in pH affects many chemical and biological processes in the water. the water.

Most aquatic organisms prefer a range of 6.5-8.0. Water Most aquatic organisms prefer a range of 6.5-8.0. Water higher or lower than the range decreases biodiversity, & higher or lower than the range decreases biodiversity, & reduce reproduction.reduce reproduction.

Low pH can also allow toxic elements to become mobile Low pH can also allow toxic elements to become mobile & “available” for uptake by aquatic plants. This can be & “available” for uptake by aquatic plants. This can be particularly dangerous to sensitive species like rainbow particularly dangerous to sensitive species like rainbow trout. trout.

Changes in pH occur from acid rain, wastewater Changes in pH occur from acid rain, wastewater treatment plants, and leaching from surrounding rock treatment plants, and leaching from surrounding rock beds.beds.

TurbidityTurbidity Turbidity measures the amount of particles suspended in a Turbidity measures the amount of particles suspended in a

body of water such as soil particles (clay, silt, sand), algae, body of water such as soil particles (clay, silt, sand), algae, plankton, microbes, and etc.plankton, microbes, and etc.

Higher turbidity increases water temperatures because the Higher turbidity increases water temperatures because the particles absorb more heat reducing the amount of DO. particles absorb more heat reducing the amount of DO. Warm water holds less DO than cold. Higher turbidity Warm water holds less DO than cold. Higher turbidity reduces the amount of light penetrating the water, and reduces the amount of light penetrating the water, and reduces photosynthesis. Suspended materials can clog reduces photosynthesis. Suspended materials can clog fish gills, decrease resistance to disease & affect egg/larval fish gills, decrease resistance to disease & affect egg/larval developmentdevelopment

Sources include soil erosion & runoff, waste discharge, Sources include soil erosion & runoff, waste discharge, eroding stream banks, bottom feeders (carp). Turbidity eroding stream banks, bottom feeders (carp). Turbidity has no direct human health effects but can provide a has no direct human health effects but can provide a medium for microbial growth. medium for microbial growth.

Indicators vs. actual chemicalsIndicators vs. actual chemicals

Ecotoxicology- pollutants in the oceanEcotoxicology- pollutants in the ocean Eating too much of certain seafood is Eating too much of certain seafood is

harmfulharmful We looked at the chemistry of the water. We looked at the chemistry of the water.

Now we will look at the chemistry of the Now we will look at the chemistry of the animals in the wateranimals in the water

Why are we concerned about Why are we concerned about ocean pollution?ocean pollution?

TransportationTransportation Coastal ocean is used most heavily-76% Coastal ocean is used most heavily-76%

of fisheries!!of fisheries!! recreation- jet skis, cruise shipsrecreation- jet skis, cruise ships

CausesCauses

Natural (not all are human-caused)Natural (not all are human-caused) Volcanoes- atmospheric pollutants (ash, SOVolcanoes- atmospheric pollutants (ash, SO22)) Underwater seepsUnderwater seeps

AnthropogenicAnthropogenic Anthro=humansAnthro=humans Industry, mining, agriculture, transportationIndustry, mining, agriculture, transportation RecreationRecreation

4 main pollutants4 main pollutants

Petroleum-least damaging, can be broken Petroleum-least damaging, can be broken down naturallydown naturally

Sewage sludge-water treatment does not Sewage sludge-water treatment does not treat for chemicals, only treats wastetreat for chemicals, only treats waste

Toxic chemicalsToxic chemicals DDT (banned), PCB’s, PAH’sDDT (banned), PCB’s, PAH’s Still in environment todayStill in environment today

Heavy metalsHeavy metals Lead, mercury, methylmercuryLead, mercury, methylmercury

What is mercury?What is mercury?

Heavy, silvery-white liquidHeavy, silvery-white liquid Only metal that is liquid at ambient temp.Only metal that is liquid at ambient temp. Mad as a hatterMad as a hatter Naturally in environment from volcanic Naturally in environment from volcanic

eruptions and weathering of rocks- but eruptions and weathering of rocks- but miniscule compared to human-causedminiscule compared to human-caused

Environmental neurotoxin affects growth, Environmental neurotoxin affects growth, reproductive success, and development in reproductive success, and development in plants and animalsplants and animals

Uses of mercuryUses of mercury

Electrical products-switches, wiring, Electrical products-switches, wiring, thermostats, batteries, etc.thermostats, batteries, etc.

DentistryDentistry Medical products-antiseptics, laxativesMedical products-antiseptics, laxatives ThermometersThermometers Pharmaceutical preservatives- thimerosalPharmaceutical preservatives- thimerosal Industrial processes- byproduct of coal-Industrial processes- byproduct of coal-

burning power plants, fossil fuel burning power plants, fossil fuel combustioncombustion

Effects of MercuryEffects of Mercury

Neurological complications on a Neurological complications on a developing fetusdeveloping fetus

Sensory disturbances (blindness)Sensory disturbances (blindness) Lack of coordination (slurred speech)Lack of coordination (slurred speech) Reproductive failureReproductive failure Impaired growthImpaired growth Loss of motor skillsLoss of motor skills Loss of IQ pointsLoss of IQ points Cardiovascular problemsCardiovascular problems

Different forms of mercuryDifferent forms of mercury

Elemental mercury-does not affect Elemental mercury-does not affect humanshumans

Inorganic mercury-does not affect Inorganic mercury-does not affect humans, gets transformed by bacteria into humans, gets transformed by bacteria into methylmercurymethylmercury

Methylmercury-also called organic Methylmercury-also called organic mercury, poisonous, absorbed into tissuemercury, poisonous, absorbed into tissue

BioaccumulationBioaccumulation: build-up in concentration : build-up in concentration of something with each step of the food of something with each step of the food chainchain Crosses the blood/brain barrier and placentaCrosses the blood/brain barrier and placenta Eliminated from living tissue very slowlyEliminated from living tissue very slowly Is contained in fish flesh and is not reduced or Is contained in fish flesh and is not reduced or

removed by cleaning, trimming or cookingremoved by cleaning, trimming or cooking BioconcentrationBioconcentration: comparison between : comparison between

creature’s concentration and concentration creature’s concentration and concentration in environment (i.e. seawater)in environment (i.e. seawater)