Enzyme-immunoassay field kits and capillary gas chromatography with nitrogen-phosphorous and
electron capture detection (NPD and ECD) systems were used to determine the levels and distribution of
commonly used pesticides (alachlor, atrazine, butylate, cyanazine, diazinon, metolachlor, metribuzin,
malathion, parathion, propachlor, pendimethalin, trifluralin) and some of their metabolites (diethyl
aniline, hydroxy alachlor, DE-atrazine, and DIP-atrazine) in surface water in Egypt. Replicate water
samples were collected from several sampling sites near Cairo, Alexandria, Damietta, and Manzala Lake,
using solid-phase concentration onto C18 cartridges, and the extract was subsequently analyzed using
GC/NPD and GC/ECD systems. Alachlor, metolachlor, trifluralin, parathion, malathion, atrazine, and
metribuzin were the most frequently detected pesticides, in the order listed, at the four sampling
locations. Alachlor had the highest concentration detected (165-254 ppb), followed by metribuzin (0.6-47
ppb), metolachlor (6.6-12.5 ppb), atrazine, (2.5-7.3 ppb), and malathion (1.5-5.7 ppb). The
concentrations of pesticides detected at Cairo were generally lower than those at the other three locations,
down stream on the Nile River. The largest number of pesticides detected was in the Damietta branch of
the Nile, and their concentration was generally higher than those detected at all other locations. Manzala
Lake is the second highest location in terms of overall frequency and concentration of pesticides
detected. The ecological and environmental health impacts of such contamination will be discussed.