Herbicides are extensively used all around the country and often become airborn or run off into streams or rivers, aiding in their spread beyond the farm fields. In one study, USGS scientists found measurable glyphosate residues in 60-80% of air and rain samples examined (Chang et al., 2011), demonstrating that routes of exposure extend beyond applicators who come into direct contact with herbicides.
For the general public, the most common route of exposure to herbicides is through residues in food and beverages, especially drinking water. Other common routes of exposure for people living in cities or suburbs, or far away from agricultural operations, stem from lawn and garden herbicide use, including applications on golf courses, in parks, and other outdoor environments.
People who live in or near farming areas where herbicides are routinely applied can also be exposed through airborne residues, blowing dirt and dust, and/or from residues that lodge on clothing.
Infants can be exposed from hand-mouth contact when their skin picks up residues in dirt or dust. Sometimes residues are brought into the home by pets.
Individuals handling, mixing, and applying herbicides are also occupationally exposed, as are those that work on or near equipment used to spray herbicides. The workers in pesticide manufacturing plants or along pesticide distribution systems can also be exposed occupationally.