Can household pets be used as reliable monitors of lead exposure to humans?

We investigated the validity of dogs and cats as sentinels of environmental lead exposure to humans. This paper reports findings from a study conducted in Granite City, IL, during the summer of 1991. At this site, a former secondary lead smelter had been in activity for more than 80 years. The smelter was shut down in 1982. The surrounding area was found to be contaminated with lead, with soil lead concentrations above 5000 ppm in some places. The Illinois Department of Public Health conducted a survey in the community to determine the effects of lead on the local population. We sampled dogs and cats owned by these people. Our results suggest that living near a closed lead smelter, with heavy soil contamination, was not associated with high blood lead concentrations in pets, or their owners. There was a significant relationship between BLC (blood lead concentrations), in indoor pets and younger children, which was consistent with our hypothesis that pets could be used to monitor childhood lead exposure. We also found that, when there was one pet with a high BLC in a house, the likelihood of finding one person with a BLC above 10 micrograms/dl was significantly increased.