''When we began this work, most of the regulations were based on studies of adult white men - the healthiest segment of the population,'' Leckie will tell an audience Feb. 16 at a symposium on toxic substances in the environment at the annual meeting of the American Association for the Advancement of Science.
The foundation of Leckie's research is careful observation of the activities of normal, healthy children in everyday environments. His video cameras have captured hours of mundane activity in the homes of middle-class suburbanites and migrant farm workers.
It is not yet clear whether trace amounts of synthetic chemicals, increasingly present in the environment, pose a risk to human health. But it makes sense to begin to consider the issue by studying children, the most vulnerable segment of the population.
Compared to adults, young children have cell walls that are more permeable to environmental toxins. Babies are born with incomplete liver and kidney functions; the ability to detoxify chemicals matures with age. Children also have higher surface-to-volume ratios. So if a child and an adult are exposed to the same environment and absorb toxins through the skin, the child will receive a greater relative dose.
Leckie has used the hours of footage to build realistic models of how children might ingest or otherwise become exposed to substances, including toxins such as lead and pesticides, which may be present in their immediate environments in small amounts. The development of th
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Contact: Dawn Levy
dawnlevy@stanford.edu
650-725-1944
Stanford University
16-Feb-2004