Ethoprop (Synonyms: Ethoprophos)

Ethoprop is an organothiophosphate nematicide and insecticide.1,2,3 It decreases the infectivity of M. chitwoodi and M. hapla second-stage juveniles (EC50s = 5.6 and 6.8 μg/ml, respectively) and inhibits hatching of M. chitwoodi egg masses and M. chitwoodi and M. hapla free eggs (EC50s = 0.2, 46, and 83.3 μg/ml, respectively).2 Ethoprop (1.8 μg/g) decreases the number of M. chitwoodi nematodes in tomato roots when added to soil from fields without previous ethoprop exposure, but is biodegraded in soil from fields previously exposed to ethoprop. In field trials, it decreases the percentage of potato tubers damaged by wireworms when applied as granules in the planting furrow at a concentration of 3 kg AI/ha.3 Ethoprop is toxic to rats via oral administration and dermal contact (LD50s = 47 and 226 mg/kg, respectively) as well as inhalation (LD50 = 0.123 mg/L).1 It is also toxic to bluegill (LC50 = 0.32 mg/L). Formulations containing ethoprop have been used in the agricultural control of pests.

|2. Mojtahedi, H., Santo, G.S., and Pinkerton, J.N. Efficacy of ethoprop on Meloidogyne hapla and M. chitwoodi and enhanced biodegradation in soil. J. Nematol. 23(4), 372-379 (1991).|3. Stewart, K.M. Chemical control of wireworms (Elateridae) in potatoes. N. Z. J. Exp. Agr. 9(3-4), 357-362 (1981).|1. Authority, E.F.S. Conclusion regarding the peer review of the pesticide risk assessment of the active substance ethoprophos. EFSA Scientific Report 66, 1-72 (2006).