September 10, 2001
Researchers link exposure to organic solvents during pregnancy to an increased risk of visual impairment in exposed children
Researchers at The Hospital for Sick Children (SickKids) and the University of Toronto have linked exposure to organic solvents during pregnancy to an increased risk of visual defects in exposed offspring. Organic solvents are chemicals found in paints, adhesives, lacquers and cleaning agents, and are used in industries such as dry cleaning, printing, and plastics manufacturing. This research was published in the September issue of the journal Teratology.
“We decided to look at the effects of prenatal exposure to organic solvents on child’s vision because visual system impairment, including colour vision loss and reduced contrast sensitivity, is commonly associated with occupational exposure to organic solvents in adults,” said Christine Till, the study’s lead author and a University of Toronto graduate student. “We wanted to see if similar visual deficits would be found in children regularly exposed to organic solvents in the womb.”
Till worked with a multidisciplinary team of researchers at The Hospital for Sick Children, including Dr. Carol Westall, an optometrist, electrophysiologist and vision scientist, Dr. Joanne Rovet, a neuropsychologist and senior scientist, and Dr. Gideon Koren, a paediatrician and toxicologist.
The study compared 32 children of women who were exposed occupationally to organic solvents during pregnancy between 1992 and 1996 with a matched control group. Participants were recruited from SickKids' Motherisk Program, a consultation service for pregnant or lactating women and their health care providers concerning the fetal risks associated with drug, chemical, infection, disease and radiation exposure during pregnancy.
Overall, the solvent-exposed children had poorer vision and problems with colour vision compared with the control group. The visual impairment may also be a marker of further central nervous system damage.
This research builds on an earlier Motherisk study that found an increased risk of major birth defects from occupational exposure to organic solvents during pregnancy, which was published in The Journal of the American Medical Association in 1999.
“We will now be looking at a larger, more comprehensive study to look at the risk of specific types of organic solvents and the levels of occupational exposure. This research may help delineate guidelines on safe levels of exposure for pregnant women,” said Dr. Koren, director of Motherisk and a senior scientist in The Hospital for Sick Children Research Institute.
This research was supported by the Canadian Institutes of Health Research (CIHR), the Natural Sciences and Engineering Research Council of Canada (NSERC), The Hospital for Sick Children Foundation, and The Physicians Services Incorporated Foundation.
The Hospital for Sick Children is a health care, teaching and research centre dedicated exclusively to children; affiliated with the University of Toronto. For more information, please visit www.sickkids.ca. For more information on Motherisk, please visit www.motherisk.org.
Women who are currently, or were recently, exposed to solvents in the workplace (e.g. factories, laboratories, or dry cleaners) during pregnancy can contact researchers at The Hospital for Sick Children for more information. Please call Christine Till at (416) 813-8281 or send an e-mail to christine.till@sickkids.ca.
For more information, please contact:
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