/ J*V v ^ Environmental Protection Agency | I Office of Pesticide Programs fe \AlZ/ f Aminopyralid in Manure and Compost November 18, 2011 ------- Aminopyralid in Manure and Compost Aminopyralid is an herbicide registered for use on rangeland, pastures, and non-cropland areas such as industrial sites, rights of way, ditch banks, and natural areas. Examples of trade names include Milestone, Chaparral, ForeFront. The EPA first approved it for use in the United States in 2005. Considered a reduced risk pesticide based on its low toxicity to humans, aminopyralid is effective in controlling noxious and invasive weeds. Potential Plant Damage Aminopyralid residues may remain in treated plant material or in manure from animals that have grazed in treated pastures or have been fed hay or forage harvested from treated pastures or crops. There have been cases where people have raised concerns about possible damage to sensitive vegetable crops following the use of compost or manure that contains residues of aminopyralid. If manure or compost containing residues of aminopyralid is applied to certain vegetable crops, it may cause unwanted plant damage. Simple Tips for Consumers Purchasing and Using Manure and Compost When purchasing or obtaining manure, manure-derived products or compost, helpful questions to ask the supplier are: • Ask the supplier to confirm that the herbicide aminopyralid has not been used to produce feed for their animals. • Ask if they have had any reports of plant damage from use of the compost or manure, and if so, find another source. . • Ask if your supplier has performed bioassays to ensure that their compost does not contain damaging levels of herbicides (bioassays are tests conducted to measure the effects of a substance on a living organism). What EPA Is Doing About the Contaminated Compost/Manure Problem We are evaluating the use of aminopyralid so as to address the contaminated compost and manure problem through labeling revisions and coordination with the registrant to improve product stewardship and public awareness of the issue. • Aminopyralid product labels were revised for the 2010 season to include stronger advisory language with information on hay and manure management (including a prominent pictogram banning the transfer of aminopyralid residues via livestock from treated plant material to manure and compost) and additional use precautions and restrictions on grazing, haying, and use of plant residues or manure. • We have continued to receive reports of plant damage from aminopyralid-contaminated manure and compost. Therefore, we are imposing additional restrictions on the pesticide's use. New labeling will prohibit distribution or sale of aminopyralid-treated ------- hay off the farm or ranch where it was treated and harvested in states where plant damage is likely based on key variables (large numbers of confined animals in the area; dependence on local forage that could have been treated with aminopyralid; and proximity to organic farms or gardens). • Dow will begin marketing some aminopyralid products with the revised labeling this year and make a full transition to these enhanced labels on all of its aminopyralid rangeland and pasture products for the 2012 season. What Dow AgroSciences Is Doing about the Contaminated Compost/Manure Problem Dow has reported taking the following corrective actions: • Dow has implemented a stewardship program aimed at preventing recurring problems. Components of the stewardship program include limitations on the sale of aminopyralid products to "walk-in" customers in some areas; preparation and distribution of fact sheets and other point-of-sale literature outlining precautions regarding transfer of treated hay or manure from animals grazing treated fields; and training of Extension Agents, distributors, commodity groups, and other centers of influence such as the Washington Hay Growers Association to ensure that the label restrictions and characteristics of aminopyralid are fully understood. • Dow has investigated reported incidents of plant damage, tracing the source of contamination, meeting with all parties involved and, in some cases removing and replacing contaminated soil. • Dow has launched a website, www.manurematters.com. with information on aminopyralid for gardeners, horse owners and stables, farmers and ranchers, hay and forage producers, and manure and compost suppliers. Health Risk Assessment for Aminopyralid Aminopyralid is a reduced risk pesticide based on its low toxicity to humans. Its use on rangeland, pastures, and non-cropland areas are not expected to pose a risk to people. EPA's risk assessments for aminopyralid concluded that aggregate risk from exposure to aminopyralid residues in food and drinking water and from the use of aminopyralid on recreational sites is estimated to be more than 100 times lower than levels that would be of concern for human health. In addition, EPA found that risk to workers applying aminopyralid products was very low, with exposures estimated to be substantially below EPA's level of concern. ------- |