The U.S Environmental Protection Agency (EPA) has regulated arsenic since the agency began. Arsenic has been used in pesticide and in medicine since the 1800s. There are arsenic EPA guidelines for the amount that is found in the soil and in the water. In 2006, the EPA implemented new rules for the amount of inorganic arsenic that can be found in drinking water to 10 per parts per billion. In 1993, the EPA banned arsenic in agricultural pesticides because it seeps into the soil. Arsenic has not been produced in the United States since 1985. Soil contamination has been a major focus of the EPA. Some wood products are treated with arsenic and the runoff may contaminate the soil in some areas. The EPA fines companies that do not dispose of arsenic properly. This is due to studies that show that arsenic causes cancer and other health problems in humans and animals.