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Table of Contents
Organics & Pesticides
The descriptions below provide general information for each topic. Click on each topic to get subwatershed specific descriptions.

Aldrin
Aldrin is an insecticide, similar in chemical structure to dieldrin. Aldrin was banned for all uses except termite control in 1974 and was banned for that use in 1987. Aldrin quickly breaks down to dieldrin in the environment and in the body. Both aldrin and dieldrin readily bind to sediment and are bioaccumulative, meaning they accumulate in the fatty tissue of the body and stored concentrations increase as it moves up the food chain. USEPA considers both aldrin and dieldrin probable human carcinogens. Other effects of exposure include headache, dizziness, and uncontrolled muscle movements.

The current water quality criteria for aldrin, which are also indicated in (Table 3), are:
-Acute criteria for protection of aquatic life: 3.0 ug/L
-Water and fish ingestion criteria for protection of human health: 0.074 ng/L
-Fish consumption criteria for protection of human health: 0.079 ng/L



Dichlordiphenyltrichloroethane (DDT)
Dichlordiphenyltrichloroethane (DDT) is a pesticide that was banned in the U.S. for environmental and health reasons in 1972. The principal breakdown product of DDT is dichlorodiphenyldichloroethylene (DDE). DDT will not dissolve readily in water but will strongly bond with soil and sediment, so a minimal detection of DDT in a water sample may be a good indication of much higher levels in the bottom sediments. DDT builds up in plants and in the fatty tissue of fish that feed from the bottom of a contaminated riverbed. Because DDT remains for long periods of time in the fatty tissues of fish, it accumulates with continued exposure, and extends up the food chain as larger animals fed on the smaller fish. Human exposure is through eating contaminated fish or other animals as well as eating root and leafy vegetables grown in contaminated soils. Large exposure to DDT affects the nervous system and can cause seizures. The EPA has determined that DDT is a probable human carcinogen.

The current water quality criteria for DDT, which are also indicated in (Table 3), are:
-Acute criteria for protection of aquatic life: 1.1 ug/L
-Chronic criteria for protection of aquatic life: 0.001 ug/L
-Water and fish ingestion criteria for protection of human health: 0.024 ng/L
-Fish consumption criteria for protection of human health: 0.024 ng/L



Dieldrin
Dieldrin is an insecticide similar in chemical structure to aldrin. Dieldrin was banned for all uses except termite control in 1974 and was banned for that use in 1987. Dieldrin occurs as a breakdown product of aldrin in the environment and in the body. Both aldrin and dieldrin readily bind to sediment and are bioaccumulative, meaning they accumulate in the fatty tissue of the body and stored concentrations increase as it moves up the food chain. USEPA considers both aldrin and dieldrin probable human carcinogens. Other effects of exposure include headache, dizziness, and uncontrolled muscle movements.

The current water quality criteria for dieldrin, which are also indicated in (Table 3), are:
-Acute criteria for protection of aquatic life: 2.5 ug/L
-Chronic criteria for protection of aquatic life: 0.0019 ug/L
-Water and fish ingestion criteria for protection of human health: 0.071 ng/L
-Fish consumption criteria for protection of human health: 0.076 ng/L



Pentachlorophenol
Pentachlorophenol is a synthetic compound that does not exist naturally in the environment. Prior to 1984 it was widely used as a pesticide and a wood preservative. In 1984 its use was restricted to only certified applicators. Today it is still used as a wood preservative. Pentachlorophenol enters river and watershed systems through evaporation from treated surfaces, disposal, and accidental spills. Human exposure can come from low levels in the air and from drinking contaminated water as well as from living near or working at wood treatment facilities. Exposure to high levels of pentachlorophenol can cause extreme high fever leading to organ and tissue damage. Liver and immune system problems have also be reported. The EPA has determined that pentachlorophenol is a probable human carcinogen.

The current water quality criteria for pentachlorophenol, which are also indicated in (Table 3), are:
-Acute criteria for protection of aquatic life: 20 ug/L*
-Chronic criteria for protection of aquatic life: 13 ug/L*
-Water and fish ingestion criteria for protection of human health: 1.01 mg/L

*pH dependent criteria, value given based on pH 7.8


Polychlorinated Biphenyls (PCBs)
Polychlorinated Biphenyls (PCBs) are a group of 209 different synthetic chemical compounds. They were historically used for coolants and lubricants in electrical equipment, as well as in carbonless copy paper and in fluorescent lining fixtures, prior to being banned in the U.S. in 1977. PCBs are still present in equipment (transformers and capacitors) at many electric transfer stations. PCBs can enter the air, water and soil from accidental spills, manufacturing activities, and disposal of PCB containing products. PCBs can bioaccumulate in the fatty tissues of fish and aquatic animals, with concentrations increasing up the food chain. Human exposure to large amounts of PCBs can cause skin problems and liver damage. PCB exposure has been loosely linked to liver cancer, however, more data is needed to confirm these preliminary findings. The EPA had classified PCBs as probable human carcinogens.

The current water quality criteria for PCBs, which are also indicated in (Table 3), are:
-Acute criteria for protection of aquatic life: 2.0 ug/L
-Chronic criteria for protection of aquatic life: 0.014 ug/L
-Water and fish ingestion criteria for protection of human health: 0.079 ng/L
-Fish consumption criteria for protection of human health: 0.079 ng/L



Polynuclear Aromatic Hydrocarbons (PAHs)
Polynuclear Aromatic Hydrocarbons (PAHs) are a group of more than 100 different chemical compounds formed from the incomplete burning of coal, oil products, and some types of garbage. They are found mainly in coal tar, crude oil, roofing tar, some pavement sealers, and cigarette smoke. PAHs can enter the water system from rain, which washes it out of the atmosphere, or from direct contact with a PAH containing product. Human exposure comes from drinking contaminated water, as well as from breathing smoke containing PAHs. The Department of Health and Human Services determined PAHs may “reasonably be anticipated” to be a carcinogen, however more data is needed for a conclusive determination.

The current water quality criteria for PAHs, which are also indicated in (Table 3), are:
-Water and fish ingestion criteria for protection of human health: 2.8 ng/L
-Fish consumption criteria for protection of human health: 31.1 ng/L

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