Analysis of Mercury in Sequential Micrometer Segments of Single Hair Strands of Fish-Eaters

The study analyzed mercury (Hg) concentrations in single hair strands of 10 fish-eaters using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) to track changes in body burden over time. Two calibration strategies were evaluated, with the first using powdered hair standard reference materials (SRMs) and an internal sulfur standard, resulting in a linear relationship between Hg and sulfur ratios. However, significant differences were found when comparing these results to cold vapor atomic absorption spectrometry (CV-AAS) due to variable ablation processes. An alternative approach calibrated Hg signals against CV-AAS measurements, revealing daily Hg deposition and significant trends in Hg concentration changes within hair segments, with individual variations ranging from 26-40%. The study demonstrated that LA-ICP-MS could effectively reconstruct time-resolved Hg exposure in hair.