Mother's Exposure to Organic Solvents While Pregnant is Associated with Subtle Effects

on Child's Cognitive, Language, and Behavioral Functioning

Chicago Children of mothers exposed to organic solvents during their pregnancies had lower scores on certain tests of language, behavior, and cognitive functioning, according to an article in the October issue of The Archives of Pediatrics & Adolescent Medicine, one of the JAMA/Archives journals.

According to the article, organic solvents are some of the most common sources of workplace chemical exposure reported by pregnant women. Organic solvents are used in dry cleaning, manufacturing, jobs involving paints and plastic adhesives, nail salons and medical laboratories, and in many other industries. Organic solvents are toxic and can harm the central nervous system. There are also reports of women who abused organic solvents during pregnancy (sniffers) delivering infants with developmental delay or birth defects, the article states.

Dionne Laslo-Baker, M.Sc., of The Hospital for Sick Children and the University of Toronto, Ontario, and colleagues compared the cognitive, language and motor skills and behavioral achievements of 32 children (age range, 3 to 9 years old) whose mothers were occupationally exposed to organic solvents during pregnancy to a matched control group of children whose mothers were not exposed to solvents during pregnancy.

Mothers in the exposed group reported being exposed to 78 organic solvents between one and 40 hours per week and between eight and 40 weeks of their pregnancies. Exposed mothers reported using protective equipment to limit exposure to organic solvents. The children in the two groups did not differ in birth weight, gestational age or age at achieving certain behavioral milestones, and none had major malformations or neurological deficits.

The researchers found that After controlling for potential confounding because of maternal IQ and maternal education, children exposed in utero to organic solvents obtained lower scores on subtests of intellectual, language, motor and neurobehavioral functioning, write the researchers.

The results of this study suggest some adverse fetal effects of occupational exposure to organic solvents during pregnancy as measured by neurocognitive, behavioral, and motor coordination measures, the authors write. Exposed children performed at a lower level than control children in subtests that measure short-term auditory memory, general verbal information, and attention. Furthermore, children who were exposed to organic solvents in utero showed reduced ability in recalling sentences, even when their global scores were within the normal range.

Reducing exposure in pregnancy is merited until more refined risk assessment is possible. Further studies that address exposure to specific solvents, dose and gestational timing of exposure are needed, the researchers conclude.

(Arch Pediatr Adolesc Med. 2004;158:956-961. Available post-embargo at archpediatrics.com)

Editors Note: This study was supported by a grant from Physician Services Inc., Toronto. Dr. Laslo-Baker received a doctoral research award from the Canadian Institutes of Health Research (CIHR), Ottawa, Ontario. Dr. Kozer received a fellowship from the Research Training Centre, The Hospital for Sick Children. Dr. Koren is a senior scientist of the CIHR and holder of the Research Leadership in Better Pharmacotherapy During Pregnancy and Lactation and The Ivey Chair in Molecular Toxicology, The University of Western Ontario, London, Ontario.