Fenitrothion

Fenitrothion (IUPAC name: O,O-dimethyl O-(3-methyl-4-nitrophenyl) phosphorothioate) is a phosphorothioate (organophosphate) insecticide that is inexpensive and widely used worldwide. Trade names include Sumithion, a 94.2% solution of fenitrothion.<ref name=pc>Template:Cite web</ref>

Health effects

Template:Medref Fenitrothion at sublethal doses affected the motor movement of marsupials,<ref>Template:Cite journal</ref> and at acute dose levels it reduced the energy of birds.<ref>Template:Cite journal</ref>

In chronic (low) dose tests, unexpectedly only the lowest concentration (0.011 microgram/liter) of fenitrothion depressed the growth of an algae, though all of the chronic dose levels used were toxic in other ways to the algae.<ref>Template:Cite journal</ref>

Just half of fenitrothion's minimally effective dose altered the thyroid structure of a freshwater murrel (the snakehead fish).<ref>Template:Cite journal</ref>

Cases of non-specific encephalopathy and fatty visceral changes (Reye's syndrome) in children living in the vicinity of fenitrothion-spraying operations invoked the research described latterly in Science,<ref>Template:Cite journal</ref> and originally in The Lancet:<ref>Template:Cite journal</ref> Template:Cquote

Further study showed that the illness was caused not by fenitrothion itself, but combinations which included the surfactants and the solvent (with or without the pesticide) clearly showed that pretreatment with these chemicals markedly increased the viral lethality in the test mice.<ref>Template:Cite journal</ref>

Resistance

In an unusual demonstration of resistance to pesticides, 8% of insects in farm fields were found to carry a symbiotic gut microbe that can metabolize and detoxify fenitrothion; after in-vitro tests showed that the microbe significantly increased the survival of fenitrothion-treated insects.<ref>Template:Cite journal</ref>

Further reading

• Template:Cite web

External links

• Template:PPDB
• Hazardous Substances Data Bank (source of data)
• Inchem
• Entox
• Re-evaluation of Fenitrothion by the Pest Management Regulatory Agency of Canada