Summary
Benomyl is a benzimidazole carbamate fungicide and ascaricide used widely in agriculture and gardening. The available data concerning benomyl exposure in human pregnancy are highly limited and potentially confounded, mainly by exposure estimations being based on occupation or residential location.
No studies have assessed the overall risk of congenital malformation. A possible association between benzimidazole pesticide exposure and an increased risk of spina bifida has been suggested in a single study. Additional data are required before conclusions regarding this specific risk can be provided. A possible clustering of infants with eye malformations in which benomyl exposure was causally implicated was reported in the 1990s. Two subsequent epidemiological studies did not provide evidence of an association but suffered a number of methodological limitations and therefore an association cannot currently be excluded.
No studies have investigated the risk of spontaneous abortion, preterm delivery, growth restriction, intrauterine death, offspring neurodevelopmental impairment or cancer following maternal exposure in pregnancy.
As with all chemicals, unnecessary exposure to benomyl should be avoided during pregnancy. However, where occupational exposure is unavoidable, adequate health and safety precautions should be taken to ensure that exposure is well within the recommended exposure limits and not associated with maternal symptoms of toxicity.
Inadvertent exposure to benomyl at any stage in pregnancy would not usually be regarded as medical grounds for termination of pregnancy. However, other risk factors may be present in individual cases which may independently increase the risk of adverse pregnancy outcome. Clinicians are reminded of the importance of consideration of such factors when performing case-specific risk assessments. Where exposure to benomyl has occurred, even in cases which did not result in maternal toxicity, enhanced fetal monitoring may be warranted. Discussion with UKTIS is recommended.
Note: This product is no longer commercially available in the UK, therefore this document will not be routinely updated. If up-to-date information is required please contact UKTIS.
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