Environmental and physiological factors affecting lead and cadmium levels in deciduous teeth

Shed deciduous teeth lead and cadmium content of children from Cartagena (Spain) was assessed. Parents were provided with an interview containing different questions concerning family socioeconomic status, child's health history, zone of residence, or home antiquity. Besides, physiological variables were considered, i.e., sex of donor, presence of caries, type of tooth donated, tooth weight, age of shedding, and position within the mouth. Tooth lead and cadmium data showed a positively skewed distribution and were log-normalized for further analyses. No statistically significant differences could be observed for lead and cadmium values according to the sex of donor. Both heavy metals decreased in content from incisors to molars and with age of shedding. The one-way analysis of variance (ANOVA) displayed both environmental and physiological risk factors contributing to high tooth lead and cadmium values. When a multifactor ANOVA was carried out, the associations between home antiquity, nail biting habit, and jaw with tooth lead levels, as well as those between zone of residence and tooth cadmium levels were found to persist. However, the only common factor for both heavy metals in the multiple analyses was the type of tooth.