“Hidden” dangers in a mass fatality aircraft crash incident: Heavy metal contamination in a forensic archaeological site in Northeast India

Bone composition is affected during the lifetime of the organism by the nutrition of the individual, whereas postmortem bone composition is affected by the surrounding burial environment. Additionally, the presence of certain elements in a buried environment can affect the structural composition of bone. The accumulation of these elements can indicate various pollutants in the working environment, both past and present. Forensic archaeologists may be exposed to contaminants that include chemical as well as biological hazards. By reconstructing the land use history of this World War II-era aircraft crash site, it is possible to preliminarily identify specific occupational hazards. The aim of the current study is to identify and characterize fragmentary (non-human) bone specimens found in forensic archaeological site in northeast India. This research also examines the presence and distribution of heavy metals within these archaeological bone samples and, therefore, within the excavated work environment. The study utilizes a multidisciplinary approach combining archaeological, anthropological, radiographic, and elemental analysis techniques. Radiographic analysis indicated altered bone mineral density in four fragmented bone samples. Whereas, elemental analysis techniques viz.; energy dispersive x-ray fluorescence (EDXRF) and inductively coupled plasma mass spectrometry (ICP-MS) showed altered concentration and distribution of the heavy metals across all the specimens. Our results demonstrate the presence of heavy metals in the recovered non-human bone specimens, implying that the burial environment was affected by the hazardous pollutants and fuel, thereby posing a significant health and occupational hazard to the forensic archaeologists.