The county data show preliminary annual high estimates of chlorpyrifos use on agricultural lands, as modeled by the U.S. Geological Survey for 2015.
EWG transformed the data from kilograms and converted to pounds (1 kg = 2.20462 lbs) for the conterminous United States.
For more information on the USGS’ process and method, please see the metadata.
For previous years’ data, see other pesticide use data.