Lead in Teeth: Reconstructing Environmental Biohistory and Health at the New York African Burial Ground Using Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry (LAICP-MS)
Joseph L. Jones, Ph.D. 1,2
- 1W. Montague Cobb Research Laboratory, Howard University
- Department of Anthropology, College of William and Mary
The study of ancestral skeletal remains continues to reveal new dimensions and important details of African diasporic biohistory. Teeth, for example, develop at known ages (through adolescence) while incorporating environmental chemical exposures associated with forced migration, diet and health. Even a single tooth crown formed over several years serves as an archive of childhood and/or adolescent living conditions; biohistories potentially formed across varied African and American settings. Here, I report on the recent analysis of enamel-lead for 44 children, women and men excavated at the 17th- and 18th-century New York African Burial Ground in lower Manhattan. This study is the first quantitative investigation of human lead exposure in early America via laser ablation- inductively coupled plasma-mass spectrometry (LA-ICP-MS). This recently-developed microprobe methodology enables the spatial mapping of lead concentration in teeth such that age-related changes in the extent and (acute versus chronic) nature of exposure are detectable. Among the key findings, enamel-lead concentrations ranged from 0.39 μg g-1 (i.e., the instrument limit of detection or LOD) to 14.7 μg g-1, suggesting negligible (background level) exposures for some while others spent their childhoods in high-lead environments. Mean enamel-lead concentration for young children (5.88 μg g-1) is over five times that of adults (1.11 μg g-1), a significant difference reflecting these groups’ mostly American versus African geographic origins, respectively. These findings shed new light on lead exposure and poisoning – persistent public and global health concerns – at the origins of African America and the nation.