Kinetics of pesticide degradation by human fresh frozen plasma (FFP) in vitro

Degradation was rapid with shortest half-lives of 19.5 s for chlorpyrifos-oxon, 6.3 min for paraoxon-ethyl and 17.9 min for dichlorvos. Heptenophos (78.0 min), mevinphos (101.8 min), profenofos (162.3 min) and malaoxon (179.7 min) showed half-lives of up to 3 h. Substantial longer degradation half-lives of 69.7-80.8 h were determined with chlorfenvinphos and bromfenvinphos. Methamidophos and omethoate showed no degradation by FFP indicated by half-lives similar to spontaneous hydrolysis. In conclusion, degradation by FFP depends on the particular OP pesticide and the used FFP batch.