One of the cheapest, most widely used weed killers in the United States has turned up within about a third of people who participated in a large study released this year by researchers at George Washington University.
Out of a pool of 14,395 people, roughly 33 percent carried detectable levels of the common herbicide 2,4-D in their urine. Researchers discovered noteworthy traces of the chemical ranging from 17 percent at the beginning of the study in 2001-2002, to almost 40 percent 10 years later.
