Studies on the determination of mercury in human beard shavings by neutron-activation and γ-ray analysis

Abstract

The determination of mercury by instrumental neutron-activation analysis has been studied with particular emphasis on hair as the matrix. The well known analytical standards orchard leaves and Bowen's kale have been compared and the value 0.164 ± 0.013 p.p.m. found for the level of mercury in Bowen's kale. Hence, the likely accuracy is ± 8% when matrices similar to Bowen's kale are analysed for mercury by the method described. All factors affecting the precision are discussed. Powdered hair and the standards were shown to be easily homogenisable; however, beard shavings were found to be generally inhomogeneous with respect to mercury distribution, especially when the mercury content was much in excess of ca. 2 p.p.m. owing to exposure of subjects to mercury in the professional working environment. The beard shavings of non-occupationally exposed human beings contained 0.1–1.5 p.p.m. of mercury. Difficulties with the establishment of a mercury mass standard for use with the method are discussed.