We previously reported associations between pesticide exposure during early pregnancy in female greenhouse workers and their children’s development and growth, including more body fat and higher blood pressure at school age. This association was mainly seen for children with a common gene variant (change in genetic material), which nearly half of the children had. One aim of this project was to investigate a possible mechanism behind this finding. We found that children who had the gene variant and were exposed to pesticides in foetal life, had a different methylation pattern in genes involved in regulation of appetite and energy balance than unexposed children or children without the gene variant. This indicates that the activity of these genes has been affected by pesticide exposure in early foetal life.
Another aim was to investigate the pesticide exposure level among pregnant women and schoolchildren. We measured degradation products of insecticides (organophosphates and pyrethroids) and the herbicidal 2,4-D in urine samples and found measurable amounts in more than 90% of the samples. The level was generally higher or at the same level as in studies from other countries. We saw no clear association between the women's urine concentrations of the pesticides and their children's birth weight and length or their head and abdominal circumference. There was a tendency for a longer ano-genital distance at 3 months in the girls related to the insecticides and shorter distance in the boys related to 2,4-D. This may indicate a weak disturbance of the children's sexual development. Finally, we investigated whether the urine concentration of insecticides in school age children was related to motor function and attention. We found no correlation for pyrethroids, but organophosphates were related to a reduced attention in girls.