Production of hair intercomparison materials for use in population monitoring programmes for mercury and methylmercury exposure

Abstract

Ten kilograms of hair obtained from India were used as the basis for two intercomparison materials, one with natural low levels of mercury and methylmercury, and one with an elevated level of methylmercury. The latter was produced by labeling the hair with a solution containing methylmercury. To convert the hair into homogeneous powders, cryogenic milling was utilized. 70% of the final material passed through a 0.075 mm sieve. Subsequent studies were carried out to establish the homogeneity of the materials and the stability of the methylmercury label. The materials will be distributed in an international intercomparison, the results from which will be used to obtain recommended values for total mercury and methylmercury.