Contamination

3 types

• Ground– Contamination of soils via deposition or

percolation

• Air– Contamination and destruction of the atmosphere

• Water– Leaching and runoff of chemicals into waterways

and percolation into aquifers

Heavy/Toxic Metals

Heavy/Toxic Metals

• Heavy metals are a class of metallic elements which are naturally occurring

• These metals cause damage to multiple organs and systems

• Almost all toxic metal exposures are due to human activity and contamination

Hexavalent Chromium Made the movie Erin Brokovich

famous

A known human carcinogen when inhaled

Has been proven to cause cancer in mice when ingested

Milwaukee tested at .18 ppb, >2x higher than the Californian standard of .06 ppb

Mercury

Mercury

• Danger depends on the form present and the likely hood of exposure

• Forms of Mercury:– Methylmercury– Elemental Mercury– Mercury Salt

Mercury• Exposure–Eating contaminated seafood–Inhalation

• How does it get into the air?–Volatilization from bodies of water–Natural events – volcanoes

• How does it get into the water?–Runoff from mines–Seepage from metal processing plants–Natural events – erosion, deposition

Mercury

• Seafood?– Bioaccumulation with in top tier predators– Positive correlation between age/size of fish and

the amount of mercury present– Seafood warnings: all states except 5

Mercury• Inhalation?– Evaporation from bodies of water– Atmospheric mercury deposits out and can be breathed in

or contaminate water• Damaging effects:– Interferes with enzyme activity and genetic replication and

processing– Development issues– Kidney failure– Gastrointestinal tract– Tremors– Gingivitis– Excitability

Lead and Arsenic

Lead• Commonly used 1940-1970’s• Where lead is found– Gasoline– Paint– Ammunition– Water pipes– Batteries

Lead

• Typically effected individuals are children ages 1-5 and working adults

• Exposure can occur from several sources, including:– Tobacco Smoke– Paint chips– Drinking water– Handling any products before 1950

Lead

• Lead Poisoning Effects:– learning disabilities– behavioral problems– Seizures– Coma– Death

Arsenic• Not a Toxic Metal, but a Toxic Metalloid• Naturally occurring element in the

groundwater of some areas• Strong carcinogen• Denser than water, sinks to the bottom of

aquifers• Deep wells• Filter

Pesticides

Pesticides

• Includes chemicals which seek to:– Kill insects– Prevent premature falling of fruit– Prevent deterioration pre- or post- harvest– Defoliants

Pesticide

• Symptoms and effects of exposure– Vomiting– Immune system suppression– Blurred vision– Impaired concentration– Asthma– Liver damage– Nervous system damage

• Examples of Dangerous Pesticides– DDT – cell disruption– Copper Arsenate – metabolism disruption– Aldrin – Enzyme disruptor

DDT• Post-WWII pesticide widely used to

eradicate mosquitos• Typically used in wetlands and areas prone

to mosquito infestations• Bioaccumulation• Decimated populations of:– Eagles, falcons, pelicans, osprey, hawks– Typically thick egg shells became paper-thin

and were crushed during attempted incubation

Fertilizers

Fertilizers

• A classic non-point source of pollution• Consists of typically limiting nutrients– Nitrates– Phosphates

• Overstimulation of aquatic plants and algae

Fertilizer

• Causes increased growth rate of aquatic plants and algae

• When these die and decompose, oxygen is required and is used up

• < oxygen in the water, < fish able to survive, leads to massive fish kills (top picture)

Gulf of Mexico Dead Zone

• Non-point fertilizer pollution drains from the Mississippi watershed into the Gulf of Mexico

• Hypoxic Zone• Positive Feedback Loop– Fertilizer > growth of algae -> large algal blooms– Block sunlight, seafloor plants die– Algae die and decay, use up all the oxygen– Fish die and decay, use up all the oxygen

• Disappear in the winter, why?

CFC’s and Ozone Depletion

• 1920’s– Freon -> Refrigerant– Replaced several other toxic chemicals including:

ammonia, chloromethane, and sulfur dioxide– Praised because they were virtually unreactive– Propellants, anti-fire, refrigerants, and solvents

• Became common in civilian society after widespread use in WWII

• Heavy usage continued into the 1970’s• 1974 -> first connection between CFC’s and

ozone destruction

CFC’s and Ozone Destruction

• 1987 – Montreal Protocol– Spurred on by seasonal ozone hole over Antarctica

• All developing countries have ceased production

• 2002 – 5,791 kilotons in products– Capture and destroy

• Alternatives– HCFC’s and HFC’s both very voltile and GHG’s

Natural Contaminants

• Hexavalent Chromium– Milwaukee water, California water

• Radioactive Elements– Radium, Radon gas

• Plant produced chemicals– Used to clear areas around the plant to decrease

competition• Arsenic– Housing development build on a large deposit of this

element

How does this stuff get there?• Dumping– Dumped barrels eventually erode and the pollutants

are able to leave the containers• Percolation– Contaminated water seeps down through the ground

and enters aquifers• Natural movement of material– Weathering, erosion

• Leaks– Damaged infrastructure allows chemicals to leave

holding areas and enter the environment

Dumping• Where?– Lakes– Rivers– Streams– Oceans– Unauthorized landfills and dumping stations

• Lake Erie Problems– Shallowest and warmest of the Great Lakes– More nutrients than are needed to sustain life– Eutrophication anoxic conditions– Smelly– Heavy metal contamination of fish– Sewage contaminated beaches

Dumping

• Cuyahoga River Fires– 1868, 1883, 1887, 1912, 1922, 1936, 1941,

1948, 1952, 1969– The 1952 fire caused $1.5million worth of

damage– Fires were all started due to sparks from a

neighboring railway igniting oil and chemical pollutants on and near the river

– Helped spur the Environmental Movement– Lead the way for the Clean Water Act of 1972– http://www.youtube.com/watch?v=nlHiaZFvcXA

Current Events: Waukesha

• Waukesha ground water– Mandated by the DNR to decrease levels– Radium -> bone cancer– Wells are too deep Why not just take water from Lake

Michigan?• Great Lakes Water Compact• Outside the Lake Michigan Watershed

– Drain wetlands and dilute the remaining water– Pump water into the county from Mil-town and pump

it back for treatment, then back into the lake– $$$$ expensive $$$$

• 13.5 million spent

Current Events: Toxic Mudslide

• 1 million m2 of chemical byproduct/waste– Hungary– Caustic Soda (NaOH) = strong alkaline conditions– Lead (Pb)– Other heavy metals

• Chemicals from the processing of Bauxite into Aluminum Oxide (aka. Alumina)

• http://www.euronews.net/2011/01/13/eu-faults-hungary-s-deadly-red-mud-classification/

Current Events: Toxic Mudslide

• Reached the Danube River, second largest river in Europe– Attempts to neutralize the sludge with binding

agents and acids

Current Events: Ogallala Aquifer• Size of Lake Huron and the single most important

source of water in the High Plains region

• At risk due to significant draw-down in some areas and little to no recharge

• Water is typically pristine, pollution is beginning to be detected– Fertilizers– Pesticides