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Water solubility of flupyrazofos is 0.8 mg/L. Log Kow = 5.24. Flupyrazofos is slowly hydrolyzed in aqueous media; DT₅₀ at pH 4, 7, and 9 are 266, 180, and 121 h, respectively. Vp 3.7 mPa (25 ?C). Flupyrazofos is a nonsystemic insecticide used for the control of caterpillars, especially diamondblack moth, Plutella xylostella, larvae.

Flupyrazofos is a new insecticide under development which has shown good activity against caterpillars, especially Plutella xylostella larvae.

Flupyrazofos is a new pyrazole organophosporus insecticide, which has a high activity against the diamond-back moth (Plutella xylostella).

The principal route of metabolism of flupyrazofos is by oxidative desulfuration to the oxon which is hydrolysed, principally via base rather than esterase catalysis, to 1-phenyl-3-trifluoromethyl-5-hydroxypyrazole. The physico-chemical parameters of flupyrazofos, including water solubility, hydrolysis rates, vapour pressure and octanol/water partition coefficients, have been reported by Kim et al. (1997).

The principal route of metabolism of flupyrazofos is by oxidative desulfuration to the oxon, followed by hydrolysis to 1- phenyl-3-trifluoromethyl-5-hydroxypyrazole and diethyl hydrogen phosphate. Flupyrazofos is degraded in soil with DT₅₀ of about 14 d.

The hydrolytic half-life at pH values 4, 7 and 9 was 266, 180 and 121 hours, respectively (Kim et al., 1997). Flupyrazofos showed good photostability. The photodegradation products which were identified were flupyrazofos oxon (2), 1-phenyl-3-trifluoromethyl-5-hydroxypyrazole (3) and the thiono-thiolo rearranged isomer O,S-diethyl O-(1-phenyl-3- trifluoromethyl)pyrazol-5-yl phosphorothioate (4) (Cho et al., 1993) (Scheme 1).

Acute oral LD₅₀ for rats is 372–605 mg/kg.