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Maize seeds obtained from ¹⁴C-ethion treated plants contained about 0.01 % of the originally applied radioactivity 1 month following the last pesticide application. Hexane and methanol extracts of the seeds accounted for 35 % and 22.5 % of the radioactive residues, respectively, with 40 % remaining in the seed cake. Commercial processing procedures resulted in a gradual decrease in the total amount of ¹⁴C-residues in oils with aged residues. The refined oil contained ¹⁴C-residues that amounted to about 30 % of the amount that was originally present. The major residues in processed oil are ethion monooxon, O,O-diethyl phosphorothioate and O,O-diethyl S-hydroxymethyl phosphorodithioate, in addition to one unknown compound. After feeding rats with the cake containing ethion bound residues, a substantial amount (71 %) of ¹⁴C-residues was eliminated in the urine, while about 12 % was excreted in the feces. About 5 % of the radioactive residues were distributed among various organs. The bound residue was quite readily bioavailable to the rats.

Persistence behavior of three combination mix formulations of insecticides viz. chlorpyriphos + cypermethrin (Action-505), profenofos + cypermethrin (Roket 44EC) and triazophos + deltamethrin (Anaconda) and their bioefficacy against melon fruitfly were studied in bittergourd fruits following spray application. Half-life values of the constituent insecticides calculated from first order dissipation kinetics were ~2-3 days. Based on acceptable daily intake values, safe waiting period of 3-days is suggested for all the three combination mix formulations at recommended dose of application. Anaconda (1 L/ha) was found to be most effective against Melon fruitfly as it gave 11.72 % (number/number) and 10.93 % (weight/weight) damage as compared to control 41.13 % and 41.16 %, respectively. Anaconda at lower and higher dose (1 and 2 L/ha) was not significantly different. Rocket (2 L/ha) and Action 505 (2 L/ha) were also found effective.

Persistence behavior of two combination mix formulations of insecticides viz. profenofos + cypermethrin (Roket 44EC) and chlorpyrifos + cypermethrin (Nacraj-505) were studied in eggplant fruits following spray application at recommended and double dose. Half-life values were calculated from first order dissipation kinetics, in case of Roket 44EC, residues of cypermethrin on fruits dissipated with half-life of 2.15-2.31 days, whereas residues of profenofos dissipated with the half-life of 0.91-1.86 days. Profenofos residues persisted beyond 7 days in soil, whereas residues of cypermethrin were below detection limit on 0-day itself. Dissipation of chlorpyrifos residues in the combination mix with cypermethrin (Nacraj-505) followed first order kinetics with the half-life values of 3.27-3.10 days. In soil, chlorpyrifos residues were below detectable limit even on 0-day at recommended dose of application. More than 90% dissipation was recorded on 7 day, although residues persisted beyond 15 days at double the recommended dose. Half life of dissipation for cypermethrin calculated from first order dissipation kinetics varied from 2.19 to 3.27 days. In soil, no residues of cypermethrin were detected even on 0-day at recommended dose.

California's surface water monitoring results from 1991 through 2010 were analyzed to determine whether 12 organophosphorus insecticides and herbicides (i.e., azinphos methyl, bensulide, dimethoate, disulfoton, ethoprop, fenamiphos, methamidophos, methidathion, methyl parathion, naled, phorate, and phosmet) and their degradates have been detected above maximum concentration limits (MCLs) in Pacific salmonid habitats. Methidathion, methyl parathion, phorate, phosmet, and the oxygen analogue of naled (DDVP) detections exceeded MCLs. Methyl parathion detections may be accounted for by monthly use trends, while methidathion detections may be explained by yearly use trends. There were inadequate phorate, phosmet, or DDVP data to evaluate for correlations with use., (© Springer Science+Business Media, LLC 2011)

The environmental behavior of 40% profenofos EC under paddy field conditions was studied. After application of 40% profenofos EC at 900 g a.i./ha level, the initial deposits of profenofos on rice plant, soil and water were found to be 32.700, 0.224 and 3.854 mg/kg respectively. Half-lives (t(1/2)) of profenofos on those substrates were observed to be 5.47, 3.75 and 3.42 days respectively. The residue levels of profenofos on rice straw, soil and rice grain were significantly affected by the dosage and frequency applied. The obtained results might help to recommend the suitable dose and calculate the safety period of profenofos application.

An experiment was conducted to evaluate the effects of some technological processes on the residual levels of profenofos, imidacloprid and penconazole in tomato fruits and products. According to their half-life (t (1/2)) values, tomato fruits can be safely harvested for human consumption or for processing purposes 3 days after the spray time of imidacloprid and penconazole and 7 days after in the case of profenofos. Pesticide residues were greatly decreased in tomato juice under cold or hot break compared with that taken from unwashed tomato fruits. A sharp decline in profenofos level was noted after treatment by pectinex ultra SP-L and benzyme M during tomato crushing.

Fifty honey samples from Virginia USA were analyzed for the presence of fluvalinate and coumaphos residues. Samples were collected from hives and from bottled honey provided by beekeepers. No coumaphos or fluvalinate residues above the limit of quantification (0.05 mg/kg) were detected in any of the samples, although trace levels (<0.05 mg/kg) of coumaphos were detected in three samples from hives and trace levels of fluvalinate were found in one hive sample. No residues were detected in any of the bottled honey samples and none of the samples exceeded the US EPA tolerance levels for either miticide.