The Globe and Mail: Study links kids' cancers to moms' exposure to pollutants
Globe and Mail, By ANDRÉ PICARD, Tuesday, January 18, 2005 - Page A17
"Most childhood cancers are likely caused by pollutants expectant mothers are exposed to during pregnancy, according to a new study. Those at greatest risk live close to busy roads and industrial areas, researchers found.In particular, they found children born of mothers living near "emission hot spots" of particular chemicals were two to four times more likely to develop leukemia and other childhood cancers before age 16. "Most childhood cancers are probably initiated by close, perinatal encounters with one or more of these high-emission sources," said George Knox, a professor emeritus at the University of Birmingham in Birmingham, U.K. Emissions that appear to raise cancer risk the most include carbon monoxide created by burning fossil fuels (notably gasoline used by vehicles) and 1,3-butadiene, also a by-product of internal combustion engines. Researchers also looked at the effect of various other industrial and environmental pollutants, including particulate matter, nitrogen oxides (both of which are associated with oil burning), as well as dioxins, benzene, and benz(a)pyrene. These chemicals can be found in engine exhaust, and smokestack emissions from various industrial and refinery processes. Dr. Knox said these chemicals -- many of which have been shown to be carcinogenic in animal tests -- are likely breathed in by the mother and passed on to the baby through the placenta. But he said that "effective direct exposure in early infancy, or through breast milk, or even preconceptually, cannot be excluded...."