Atrazine in
North Carolina’s Water
a fact sheet from Toxic Free NC
Printer-friendly PDF of this factsheet (112 KB)
Effects
on wildlife Data published in 2003 show that male frogs exposed to extremely low levels of atrazine (0.1 ppb) developed major abnormalities in their reproductive tracts. 20% of the animals exposed underwent complete sex-reversal, becoming hermaphrodites, while another 36% showed underdeveloped testes. (1) Dr. Hayes research makes a compelling case that pesticides are a major contributor to the decline in amphibian populations across the country, and provides vital background for new science connecting exposure to hormone-mimicking pesticides like atrazine with serious human health problems like prostate cancer, breast cancer and declining sperm count. (1) Hayes et al. 2003. “Atrazine-Induced Hermaphroditism at 0.1 PPB in American Leopard Frogs: Laboratory and Field Evidence.” Env Health Persp 111. |
What is atrazine?
Atrazine is the most widely used herbicide in the United
States, and is applied by farmers primarily to corn and
sorghum crops. Atrazine is also used as an ingredient in
some “weed and feed” products used by homeowners
and lawn care companies. Atrazine is relatively persistent
in both soil and water, and can move through the soil to
contaminate ground water in areas where it is used.
In North Carolina, atrazine is applied to about 67% of cornfields, for a total estimated use of around 603,000 pounds by North Carolina farmers every year. (i) Nationally, farmers use an estimated 75 million pounds of atrazine every year.ii While it is widely used in the United States, atrazine has been banned by the European Union and in several African countries.
Atrazine in
our waterways
In a ten-year study of the nation’s streams and ground
water, atrazine was the pesticide most frequently detected
in water samples by the USGS. (iii) In agricultural areas,
atrazine was found in nearly 90% of streams and 40% of ground
water samples. In urban areas, atrazine was found in nearly
75% of streams and over 25% of ground water samples. (iv)
The USGS detected atrazine in low and medium levels across
North Carolina’s streams and ground water, with increasing
concentrations in the eastern part of the state. Because
atrazine readily dissolves in water, it can evaporate and
be moved by rainfall to areas with no agricultural use, such
as the Obed National Wild and Scenic River in the Upper Tennessee
River basin. (v) Atrazine has been detected in groundwater
as far as 600 miles from the site of application.
Atrazine in
drinking water
Besides contaminating ground water (where well users draw
their water), atrazine can also contaminate the streams,
rivers and lakes that supply public drinking water systems.
Atrazine has been measured at drinking water intake sites
as well as in treated drinking water at North Carolina treatment
plants in Burlington, High Point, Greensboro and Raleigh.
(vi) Because typical drinking water treatment does not remove
chemicals like atrazine from drinking water, concentrations
of atrazine are similar before and after water treatment.
(vii)
Health effects
While atrazine is not acutely toxic when ingested, exposure
to atrazine has been linked to many kinds of health effects
in the laboratory. Animals exposed to atrazine in the laboratory
have experienced respiratory distress, paralysis of the
limbs, structural changes in the brain, heart, liver, lungs,
kidneys, ovaries and endocrine organs, as well as growth
retardation. Atrazine has also been linked to cancers in
the mammary glands, as well as prostate cancer and lymphoma.
(viii)
Atrazine can also interfere with the sex hormones of animals exposed in the laboratory and in the wild. Recent research has shown that frogs exposed to very low levels of atrazine (0.1 ppb) developed both male and female sex organs (see box, above). The “safe” drinking water standard for atrazine set by the US Environmental Protection Agency is 3 ppb.
(i) NC Agricultural Statistics Service. “Corn:
Agricultural Chemical Applications North Carolina 2005.” Available
at: http://www.ncagr.com/stats/pest_use/acacnyr.htm (last
visited 3/2/2007).
(ii) Gilliom et al. 2006. “Pesticides in the nation’s
streams and ground water, 1992 – 2001.” U.S.
Geological Survey,
Ciruclar #1291, p. 45.
(iii) Gilliom 2006.
(iv) Gilliom 2006, p. 11.
(v) Gilliom 2006, p. 27
(vi) Jones, S.J. 2003 “Pesticide residues in surface
waters of North Carolina rural and urban watersheds: Studies
to determine and reduce residues in drinking water.” Dissertation
in Toxicology, North Carolina State University.
(vii) Jones 2003, pp. 144-147.
(viii) “Atrazine chemicalWATCH Factsheet.” 2003.
Beyond Pesticides.