Authors
Petrelli, G. and Figà-Talamanca, I.

Title
Reduction in fertility in male greenhouse workers exposed to pesticides

Journal
European Journal of Epidemiology: 17; 675-677. 2001.

Summary
A number of pesticides have been implicated as having reproductive and endocrine effects. Greenhouse workers are unique in their exposure to pesticides because their exposure occurs continuously throughout the year and their dose is potentially greater than that delivered to outdoor agricultural workers. Greenhouse workers work in more confined spaces where vapors can accumulate and contact with residue on plants is much more probable.

Petrelli et al. set out to investigate if an association existed between male exposures to pesticides and fertility by measuring time to pregnancy (TTP). In this study, 127 greenhouse workers and 173 administrative workers from the same geographical area were recruited. The greenhouse workers were exposed to several suspected reproductive toxic pesticides including benomyl, carbaryl, dichlorvos, endosulfan, lindane, metolachlor, methoxichlor, procymidon, and vinclozolin.

Greenhouse workers were asked to provide the type of crops, type of greenhouse (plastic or glass), the ventilation in each structure, their mixing, handling and application of pesticides, the commercial products and active ingredients used, and their use of personal protective equipment. As well, a complete reproductive history was gathered. TTP was defined as the time interval between the start of unprotected intercourse and a clinically recognizable pregnancy. The number of hours of pesticide application per year was used as a surrogate for pesticide exposure. Two exposure groups were created: Low (1-100hrs.) and High (>100hrs). Within the questionnaire were questions related to several demographic variables that may have confounded the results.

The authors found that the mean TTP for green house workers was 5.4 months (S.D. 5.6) while TTP for administrative workers was 3.9 months (S.D. 3.1). Those greenhouse workers who did not use protective equipment had a TTP of 6.1 months (S.D. 4.4). Logistic regression showed that workers with >100 hours of application per year had a significant increase in risk of conception delay (OR=2.4, CI=1.2-5.1).

The findings are suggestive that greenhouse workers experience a small delay in conception compared to other workers though, the large standard deviations make the results imprecise. In addition, the exposure assessment was extremely weak. The indirect measurement of exposure intensity (hours of application) may have misrepresented the true effect. As well, there is no evidence that the effect was endocrine mediated. Nevertheless, these results are important because they examine a population that is highly exposed to several suspected endocrine disruptors and suggest that further study is required.