A study was conducted to determine the health effects of lead-contaminated soils in dogs, cats and children residing near a secondary lead smelter. The sample sizes were 84 dogs and 26 cats in 80 households with a total of 198 humans.
Animals living outside, exposed to soit were more at risk of having a high blood lead concentration (BLC) than pets living inside The strongest correlation between children and pets sharing the same household was between younger children (~ 6 years of age) and indoor animals. The likelihood of finding someone in the household with a high BLC was significantly increased when a pet was found to have a high BLC. However, the range of BLC was fairly small compared to those found in previous studies « 5 to 28 ug/dl in pets, and 1 to 13 ug/dl in humans). Thus, the overall risk from lead contamination in this study appeared limited The most significant changes in blood or serum biomarkers in either dogs or cats was reduced d-aminolevulinic acid dehydratase activity (ALAD), while free erythrocyte protoporphyrin was increased only when BLC was above 20 ug/dl.
The following conclusions were made 1) Dogs and cats in the household are more at risk than their owners of having high BLC when exposed to a similar environment 2) Soil lead concentrations should not be the major parameter used to estimate the risk of increased lead exposure to humans or their pets, since many other factors influence the bioavailability of lead, e g, soil characteristics (pH and cation exchange capacity), lead particle size and chemical form, lifestyles of both animals and humans
3) Monitoring dogs and cats would be a cost-effective way to predict risks to humans, if any, associated with a lead-contaminated environment