Weed Killers By The Glass
September 1, 1995

Weed Killers By The Glass: Fort Wayne, Indiana

Citizen Monitoring Results

Fort Wayne drinking water is contaminated with cancer causing weed killers at levels that frequently exceed federal standards. Tests of city tap water found up to nine pesticides or metabolites in a single sample of water. The most common pesticide contaminant was atrazine, which was found in every tap water sample tested. Cyanazine was found in 71 percent of these same samples. During this test period about 12,000 infants in Fort Wayne consumed infant formula reconstituted with water contaminated with up to nine toxic weed killers. (Note 1: Ershow, Abby G., and Cantor, Kenneth P. 1989. Total Water and Tapwater Intake in the United States: Population-Based Estimates of Quantities and Sources. Life Sciences Research Office; Federation of American Societies for Experimental Biology. Bethesda, MD)

Most of these weed killers are used in corn production. Since 1985, taxpayers have subsidized Indiana corn growers at a rate of $278 million per year, for a ten-year total of $2.78 billion. Farmers in turn pay nothing to clean up the water. The pesticide industry claims farmers' weed control costs would double if these polluting herbicides were banned. Assuming industry's claim is true, the added costs would amount to just 11 percent of the value of the subsidy taxpayers pay to corn farmers each year.



Causes mammary gland cancer in female rats in repeated studies.(Note 2: Copley, Marion. 1989. Follow-up to the Third Peer Review of Atrazine. EPA. Washington, D.C.; International Agency for Research on Cancer. 1991. World Health Organization. IARC Monographs on the Evolution of Cancer Risk to Humans. Vol. 53.) Classified by the EPA as a possible human carcinogen. Federal health standard in drinking water -- 3 parts per billion (ppb), European drinking water standard 0.1 ppb.


  • Found in 100 percent of 15 tap water samples
  • 36 percent of samples were above the federal health standard
  • Highest level found -- 10 ppb, more than three times the federal health standard.
  • Average concentration -- 3.69 ppb, also above the federal health standard.



Causes mammary gland cancer in rats and birth defects in rats and rabbits in repeated studies. Causes genetic mutations. According to the EPA, this makes cyanazine a potent carcinogen.(Note 3: Dykstra, William. 1991. Peer Review of Cyanazine (Bladex). EPA. Washington, D.C.) Classified by the EPA as a possible human carcinogen, required birth defects warning on the product label. Federal health guideline in drinking water -- 1 ppb, European drinking water standard 0.1 ppb.


  • Found in 71 percent of samples
  • 50 percent of samples were above federal health advisories
  • Highest level found -- 4.8 ppb, nearly five times the federal health standard.
  • Average concentration -- 1.41 ppb, well above the federal health standard


Tests for Multiple Weed Killers


  • Nine pesticides or metabolites -- atrazine, cyanazine, simazine, metolachlor, desisopropylatrazine, desethylatrazine, alachlor, acetochlor, and metribuzin, -- were found in Fort Wayne tap water sampled on June 1, 1995. Three of these herbicides (atrazine, cyanazine, and alachlor) exceeded federal health standards.
    • These nine pesticides or metabolites include two pesticides classified by the EPA as probable human carcinogens, four classified as possible human carcinogens, one pesticide that causes for birth defects in animal studies, and four pesticides that disrupt the normal functioning of the hormone system.
    • Federal drinking water standards do not account for this simultaneous exposure to multiple pesticides (or other contaminants) in drinking water, and allow cancer risks from these weed killers up to 25 times higher than the federal government allows from the same chemicals in food.


    Use of 6 Major Herbicides on Indiana Corn Reached 18 Million Pounds in 1994, up 2.3 Million Pounds Since 1990


    Herbicide Acres Treated, 1994 Use, 1994 (lbs.)
    Acetochlor 240,000 361,000
    Alachlor 1,400,000 3,005,000
    Atrazine 5,300,000 7,190,000
    Cyanazine 1,159,000 2,487,000
    Metolachlor 2,623,000 4,911,000
    Simazine 122,000 130,000

    (Note 4: USDA 1995. Agricultural Chemical Usage: 1994 Field Crops Summary.)