(Beyond Pesticides, August 24, 2007) The Wisconsin Natural Resources Defense Board recently passed stricter limits on allowable groundwater levels of alachlor-ESA, the breakdown product of the herbicide alachlor, cutting in half the standard to 20 parts per billion (ppb). The reduction from the previous standard of 40 ppb was prompted by the state Department of Natural Resources (DNR), which has tried to pass a similar measure in recent years, only to be blocked by the Republican-controlled Senate. Officials hope that a Democratic majority will ensure adoption of the new standard.
The board voted 7-0 in favor of lowering the allowable groundwater level of alachlor-ESA, after DNR cited studies showing the chemical causes blood problems in rats. Department of Agriculture, Trade & Consumer Protection (DATCP) tests in 2001 showed alachlor-ESA in 28 percent of private wells tested, in spite of its declining use (on less than a quarter of the state’s 100,000 acres of corn).
A similar proposal was rejected by the board in 2005, when DNR refused to agree to the Joint Committee for Review of Administrative Rules’ request to allow Monsanto, manufacturer of alachlor, to fund a separate study in addition to the state’s data. Monsanto, as expected, issued a statement defending its product and supporting groundwater standards based on “sound science.” The Wisconsin Corn Growers Association also came out against the stricter rule, claiming competitive disadvantage for the state’s farmers. “It does not make it any easier for Wisconsin corn growers,” said Executive Director Bob Oleson.
But supporters of the outcome support the intention of the board. “I hope the Assembly committee will support the public health interests instead of Monsanto’s image interests,” said Rules Committee co-chairman Sen. Bob Jauch (D-Poplar). “We’re not here to do Monsanto’s bidding. We’re here to do the public’s bidding.”
According to the Environmental Protection Agency (EPA), parent compound alachlor’s health effects include skin and eye irritation, and long-term exposure can cause liver, kidney, and spleen damage, and is carcinogenic. EPA has found alachlor in water at levels over the Maximum Contaminant Level in at least fifteen states. It is a groundwater contaminant threat because “once alachlor enters ground water, its breakdown is very slow.”
For more information on groundwater contamination and the risks pesticides pose to water, download Beyond Pesticides’ brochure, Threatened Waters: Turning the Tide on Pesticide Contamination.
Sources: Associated Press, Milwaukee Journal Sentinel, EPA