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Administrative data

Link to relevant study record(s)

Description of key information

No studies are presented and none are required. Data on the toxicokinetic properties of fenitrothion are taken from the 2006 EFSA Scientific Report.

Fenitrothion (FNT) is rapidly and almost completely absorbed. It is mainly distributed to the liver, blood and carcass. Elimination is very rapid. The main metabolites are the phosphate fenitrothion (FNO), the mono methyl analogues of FNT and FNO (DM-FNT and DM-FNO respectively) and 3methyl-4-nitrophenol (NMC) and its corresponding sulphate and glucuronide.

Key value for chemical safety assessment

Bioaccumulation potential:
low bioaccumulation potential
Absorption rate - oral (%):
100
Absorption rate - dermal (%):
20.9
Absorption rate - inhalation (%):
100

Additional information

Absorption, distribution, excretion and metabolism in mammals

Rate and extent of absorption

Rapid and almost complete oral absorption (86–100 % in urine after 7 days after a low or high dose).

Dermal absorption 3.9% (concentrate) and 20.9% (dilution) for a microencapsulated product; a value of 20% is used for risk assessment purposes.

Inhalation absortion assumed to be 100% (default).

Distribution

Well distributed into organs and tissues. Liver>>whole blood>residual carcass after low dose

Potential for accumulation

Limited potential

Rate and extent of excretion

Rapid; 88-99.8 % in urine within 24 hours after a low dose

Metabolism

Extensively metabolised. No parent recovered in urine of rats, mice, rabbits and dogs. Primarily conjugates of parent, fenitrothion and conjugates and 3-methyl-4-nitrophenol and conjugates