UPTAKE, EXCRETION, AND METABOLISM OF PHORATE IN THE LAND SNAIL, HELIX-ASPERSA (MULLER)

Uptake, excretion, and metabolism of phorate (O,O-diethyl S-ethyltkiom ethyl phosphorodithioate) following application to lettuce leaves were investigated in the land snail, Helix aspersa. Snails were fed on a l eaf disc of lettuce immersed in a solution of 100 ppm of phorate. Snai ls were dissected at time intervals between 1 and 7 days after dosing. Phorate was readily absorbed within 24 hrs following ingestion. The a mount of phorate reached a peak value of 880 mu g at 4 days, and then dropped as time passed to the end of experiment (7 days) indicating th ere was no accumulation of the compound in the snail tissues. Phorate was metabolized to phorate sulfoxide and phorate sulfone. Phorate and/ or its metabolites were rapidly excreted soon after ingestion. The maj or compound identified in the excreta was the unchanged phorate.