Association of Environmental Cadmium Exposure with Pediatric Dental Caries

BACKGROUND Although animal experiments have shown that cadmium exposure results in severe dental caries, limited epidemiologic data are available on this issue. OBJECTIVES We aimed to examine the relationship between environmental cadmium exposure and dental caries in children 6-12 years of age. METHODS We analyzed cross-sectional data, including urine cadmium concentrations and counts of decayed or filled tooth surfaces, from the Third National Health and Nutrition Examination Survey. We used logistic and zero-inflated negative binomial (ZINB) regression to estimate the association between urine cadmium concentrations and caries experience, adjusting these analyses for potential confounders including environmental tobacco smoke (ETS). RESULTS Urine cadmium concentrations ranged from 0.01 to 3.38 ng/mL. Approximately 56% of children had experienced caries in their deciduous teeth, and almost 30% had been affected by caries in their permanent dentition. An interquartile range (IQR) increase in creatinine-corrected cadmium concentrations (0.21 microg/g creatinine) corresponded to a 16% increase in the odds of having experienced caries in deciduous teeth [prevalence odds ratio (OR)=1.16; 95% confidence interval (CI), 0.96-1.40]. This association was statistically significant in children with low ETS exposure (prevalence OR=1.30; 95% CI, 1.01-1.67). The results from the ZINB regression indicated that, among children with any caries history in their deciduous teeth, an IQR increase in cadmium was associated with 17% increase in the number of decayed or filled surfaces. We observed no association between cadmium and caries experience in permanent teeth. CONCLUSIONS Environmental cadmium exposure may be associated with increased risk of dental caries in deciduous teeth of children.