Atrazine is the most commonly used herbicide in the United States, with application of approximately 76,000,000 pounds (34,000 t) of the active ingredient in 1997.
The U.S. EPA said in the 2003 Interim Reregistration Eligibility Decision, "The total or national economic impact resulting from the loss of atrazine to control grass and broadleaf weeds in corn, sorghum and sugar cane would be in excess of $2 billion per year if atrazine were unavailable to growers." In the same report, it added the "yield loss plus increased herbicide cost may result in an average estimated loss of $28 per acre" if atrazine were unavailable to corn farmers.
In 2006, the EPA concluded that the triazine herbicides posed "no harm that would result to the general U.S. population, infants, children or other... consumers."
EPA concluded, in 2007, that atrazine does not adversely affect amphibian gonadal development based on a review of laboratory and field studies, including studies submitted by the registrant and studies published in the scientific literature.
In 2009, Paul Winchester, a professor of pediatrics at the Indiana University School of Medicine, wrote a paper that was published in Acta Paediatrica reviewing national records for thirty million births, found that children conceived between April and July, when the concentration of atrazine, mixed with other pesticides, in water is highest, were more likely to have genital birth defects.
A 2010 study, conducted by the U.S. Geological Survey, observed substantial adverse reproductive effects on fish from atrazine exposure at concentrations below the USEPA water-quality guideline.
In 2014, New Yorker writer Rachel Aviv reported that atrazine manufacturer Syngenta might have been orchestrating an attack on the "scientific credibility" of not just Tyrone Hayes, the lead critic of atrazine use, but other scientists as well whose studies have shown atrazine to have adverse effects on the environment and/or human and animal health.
The use of DDT in the United States is banned, except for a limited exemption for public health uses. The ban is due in a large part to Rachael Carson's book Silent Spring. The ban on DDT is cited by scientists as a major factor in the comeback of the bald eagle in the continental United States.
US scientists have found that some pesticides used in farming disrupt the nervous systems of frogs, and that use of these pesticides is correlated with a decline in the population of frogs in the Sierra Nevada.
Some scientists believe that certain common pesticides already exist at levels capable of killing amphibians in California. They warn that the breakdown products of these pesticides can be 10 to 100 times more toxic to amphibians than the original pesticides. Direct contact of sprays of some pesticides (either by drift from nearby applications or accidental or deliberate sprays) can be highly lethal to amphibians.
Being downwind from agricultural land on which pesticides are used has been linked to the decline in population of threatened frog species in California.
In Minnesota, pesticide use has been causally linked to congenital deformities in frogs such as eye, mouth, and limb malformations. Researchers in California found that similar deformities in frogs in the US and Canada may have been caused by breakdown products from pesticides which themselves did not pose a threat.
Pesticide residue in food
The Pesticide Data Program, a program started by the United States Department of Agriculture is the largest tester of pesticide residues on food sold in the United States. It began in 1991, and has since tested over 60 different types of food for over 400 different types of pesticides - with samples collected close to the point of consumption. Their most recent summary results are from the year 2005:
For example, on page 30 is comprehensive data on pesticides on fruits. Some example data:
Fresh Fruit and Vegetables
Number of Samples Analyzed
Samples with Residues Detected
Percent of Samples with Detections
Different Pesticides Detected
Different Residues Detected
Total Residue Detections
They were also able to test for multiple pesticides within a single sample and found that:
These data indicate that 29.5 percent of all samples tested contained no detectable pesticides [parent
compound and metabolite(s) combined], 30 percent contained 1 pesticide, and slightly over 40 percent