Note
Aerial applications of organophosphorous pesticides are widely used to control adult mosquitopopulations in the State of Florida. Because the pesticide may drift into estuarine water andaffect non-target organisms, a field study was conducted to determine fenthion, malathion, andnaled concentrations and disappearance rates in a salt marsh water body. Concentrationnormally increased and peaked at .75, .95 and 1.40 hrs after an aerial spray for fenthion,naled and malathion, respectively. The concentration then gradually decreased and after 48hours, only a trace (< 0.01 µg/l) was detected.