Heavy metals in human teeth dentine: A bio-indicator of metals exposure and environmental pollution

Chemosphere. 2017 Jun:176:221-230. doi: 10.1016/j.chemosphere.2017.02.114. Epub 2017 Feb 22.

Abstract

With rapid urbanization and large-scale industrial activities, modern human populations are being increasingly subjected to chronic environmental heavy metal exposures. Elemental uptake in tooth dentine is a bioindicator, the uptake occurring during the formation and mineralization processes, stored to large extent over periods of many years. The uptake includes essential elements, most typically geogenic dietary sources, as well as non-essential elements arising through environmental insults. In this study, with the help of the Dental Faculty of the University of Malaya, a total of 50 separate human teeth were collected from dental patients of various ethnicity, age, gender, occupation, dietary habit, residency, etc. Analysis was conducted using inductively coupled plasma-mass spectrometry (ICP-MS), most samples indicating the presence of the following trace elements, placed in order of concentration, from least to greatest: As, Mn, Ba, Cu, Cr, Pb, Zn, Hg, Sb, Al, Sr, Sn. The concentrations have been observed to increase with age. Among the ethnic groups, the teeth of ethnic Chinese showed marginally greater metal concentrations than those of the Indians and Malays, the teeth dentine of females generally showing greater concentrations than that of males. Greater concentrations of Hg, Cu and Sn were found in molars while Pb, Sr, Sb and Zn were present in greater concentrations in incisors. With the elevated concentration levels of heavy metals in tooth dentine reflecting pollution from industrial emissions and urbanization, it is evident that human tooth dentine can provide chronological information on exposure, representing a reliable bio-indicator of environmental pollution.

Keywords: Dentine; Environment; Heavy metal; Human teeth; ICP-MS; Pollution.

MeSH terms

  • Adolescent
  • Adult
  • Dentin / chemistry*
  • Environmental Exposure / analysis*
  • Environmental Monitoring / methods*
  • Environmental Pollutants / analysis*
  • Ethnicity
  • Female
  • Humans
  • Industrial Waste
  • Male
  • Metals / analysis
  • Metals, Heavy / analysis*
  • Metals, Heavy / pharmacokinetics
  • Middle Aged
  • Sex Factors
  • Trace Elements / analysis
  • Young Adult

Substances

  • Environmental Pollutants
  • Industrial Waste
  • Metals
  • Metals, Heavy
  • Trace Elements