What pesticides did NAWQA study?
NAWQA measured the broadest range of pesticide compounds ever addressed in a national study. Even so, many pesticides in current use and most pesticide degradates were not measured. Most NAWQA water samples were analyzed for 75 pesticides and 8 degradates, including 20 of the 25 most heavily used herbicides and 16 of the 25 most heavily used insecticides, but few fungicides, fumigants, or other types of pesticides. In addition, 32 organochlorine pesticide compounds were analyzed in bed sediment and (or) fish tissue, including 19 parent pesticides and 13 degradates or manufacturing by-products. Most of the organochlorine pesticides are no longer used in the United States, but the parent compounds, degradates, or by-products still may persist in the environment. Although pesticide compounds analyzed by NAWQA represent many of the heavily used herbicides and insecticides, they only included a fraction of all pesticides currently in use, and few of their degradates. NAWQA findings can prov
