Childhood Lead Exposure in North Atlantic Fisheries: Concentration and Isotopic Analyses of Tooth Enamel From 18th to 19th Century Fishing Communities

Objectives

This bioarcheological study explored the extent and sources of childhood lead (Pb) exposure in contexts where environmental sources were not anthropogenically enriched.

Materials and Methods

Sampled Pb concentrations and isotope ratios in the tooth enamel (2nd molars) of 46 individuals from five early fishing settlements in Newfoundland and Nova Scotia and 19 individuals from a mid-18th century Royal Naval cemetery in Newfoundland.

Results

Pb concentrations were as much as 20 times higher than natural exposures (mean = 6.9, maximum = 28.7). Pb exposure in these fishing communities was higher than in previous studies, with expected natural exposure but not as high as industrial period sites in England or cemeteries associated with local mining activities in North America. Most Pb isotope ratios were consistent with English/Welsh and Western European Pb ore (²⁰⁶Pb/²⁰⁴Pb = 18.30–18.46, ²⁰⁸Pb/²⁰⁶Pb = 2.082–2.095), likely from imported Pb-containing cultural materials such as ceramics. However, Pb outliers (²⁰⁶Pb/²⁰⁴Pb = 18.86–18.91, ²⁰⁸Pb/²⁰⁶Pb = 2.055–2.058) are consistent with values seen at other 19th-century cemetery sites in North America and New Zealand.

Discussion

Since Pb mining was nonexistent in Newfoundland and there were limited environmental sources, exposures must have been from imported cultural materials. Previous studies have likely underestimated the contribution of Pb in cultural materials to historical contamination levels in archeological samples. Our study contributes to understanding the physical versus cultural environments' role in Pb exposure and the utility of Pb isotope ratios for identifying distinct cultural groups during the 18th and 19th centuries.