Neurochemical Research

, Volume 19, Issue 5, pp 569–574 | Cite as

The effect of trichlorfon and other organophosphates on prenatal brain development in the guinea pig

  • Anna Mehl
  • Tore M. Schanke
  • Bjørn A. Johnsen
  • Frode Fonnum
Original Articles


The organophosphates trichlorfon, dichlorvos, dimethoate, soman, triortho-cresyl phosphate (TOCP), and the diethoxy-analogue of trichlorfon (O,O-diethyl 2,2,2-trichloro-1-hydroxyethylphosphonate, ethyl-trichlorfon), were administrated to guinea pigs between day 42 and 46 of gestation. When the offsprings were examined at birth, there was a severe reduction in brain weight in the case of trichlorfon and dichlorvos, but not after treatment with the other organophosphates. The reduction in weight was most pronounced for cerebellum, medulla oblongata, thalamus/hypothalamus and quadrigemina. The effect was less marked for cerebral cortex and hippocampus. Since soman, a potent anticholinesterase, and TOCP, an inhibitor of neuropathy target esterase, did not show any effects, this excludes that the brain hypoplasia can be caused by inhibition of these two enzymes. Further, the lack of effect with ethyl-trichlorfon has shed some light on the part of the trichlorfon molecule which could be involved in the formation of the hypoplasia. It is suggested that alkylation of DNA may be involved in the development of the lesion. The possible consequences for a teratogenic effect of trichlorfon and dichlorvos on humans are discussed.

Key Words

Brain development dichlorvos dimethoate guinea pig organophosphates soman teratogen trichlorfon tri-o-cresyl phosphate Acetylcholinesterase 


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Copyright information

© Plenum Publishing Corporation 1994

Authors and Affiliations

  • Anna Mehl
    • 1
  • Tore M. Schanke
    • 1
  • Bjørn A. Johnsen
    • 2
  • Frode Fonnum
    • 2
  1. 1.Institute of Biology, Dept. of Molecular Cell BiologyUniversity of OsloOsloNorway
  2. 2.Division for Environmental ToxicologyNorwegian Defense Research EstablishmentKjellerNorway

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