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Toxic Substances in the Environment

Toxic pesticides within stream sediments and in aquatic organisms pose significant threats to ecosystems and human health. In 1998 Montana ranked 20th in the nation in the amount of toxic substances released by manufacturers. Toxic substances are chemicals or compounds whose manufacture, processing, distribution, and use or disposal may pose an unreasonable risk or injury to health of the environment. Because toxic chemicals have the capability to enter the body by absorption through the skin, toxins can produce an adverse biologic effect or damage in a living organism. Once toxic chemicals drain or seep into a water supply, they may be ingested into the human body by drinking, bathing, or breathing them.

Montana Polluted Waters 1998 EPA Map

This colored coded map shows the rivers, streams, lakes, and wetlands impaired by various pollutants as reported by Montana in the 303 (d) list sent to the Environmental Protection Agency. The river and stream bar chart shows 29,550 miles of pollution impairment and the five types of pollutants responsible. The lake and wetland bar chart shows 1,470,302 acres of pollution impairment and the five types of pollutants responsible. (Higher Resolution Version - pdf (Acrobat) 450K)

Today, more than 20 years after being prohibited for use in agriculture, traces of DDT and other organochlorine pesticides are still commonly found. Because toxins tend to accumulate in river and lake sediments, chemicals such as these reach their highest levels in aquatic organisms and sediments in the hydrologic system. Many watersheds cannot escape the legacy of these toxic compounds and their potential to affect the development, reproduction and behavior of fish, wildlife and humans remains.

Toxic chemicals can impact humans in the following ways, 1) through carcinogens that cause cancer, 2) by mutagens that may cause a change in the inherited genetic material of a cell, or 3) by teratogens that can cause birth defects in an embryo as it is developing in the womb during pregnancy.

Because of their contact with pesticides, herbicides and fertilizers, farmers suffer high rates of cancer, according to a study by the National Cancer Institute. Cancers such as Hodgkins disease, multiple myeloma, melanoma and cancers of the lip, stomach and prostate are common in toxic substance handlers.

The EPA reported recently that manufacturing plants in the state released 51.5 million pounds of toxic waste. Nationally, manufacturers discharged 2.5 billion pounds of toxic materials into the air or water, underground or on land. This was a 5.3 percent reduction from 1995. Montana's releases, however, represented a 17 percent INCREASE over a 3-year period, the fifth largest growth rate in the country. Idaho, Arizona, Utah and Arkansas held the top 4 spots. Toxic release statistics lag 2 years because of the large amount of information EPA compiles.

The ASARCO lead smelter in East Helena and Smurfit-Stone Container Corp. of Missoula are the top producers of toxic waste in the state. Other manufacturers producing toxic waste include Plum Creek Manufacturing in Columbia Falls, Columbia Falls Aluminum Co., Holly Sugar in Sidney, Exxon Corp. refinery in Billings, Louisiana-Pacific in Missoula, Cenex refinery in Laurel, Conoco refinery in Billings, and Montana Refining Co. in Great Falls. ~

Also see: Toxins

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