Environ. Sci. Technol. 2006, 40, 3423-3428
IVAN M. KEMPSON* AND WILLIAM M. SKINNER Ian Wark Research Institute, University of South Australia, Mawson Lakes, S.A., 5095, Australia
to reveal fundamental considerations that analysts should be aware of when considering hair analysis, particularly when bulk analytical methods are used. These techniques (i.e., ToF-SIMS and SXRF) offer the ability to provide highly detailed analysis, generating information and insights that have not been presented before. Large population studies are, however, difficult to perform with these methods, and as such, this work is limited to generating hypotheses based on a limited sample base.
K. PAUL KIRKBRIDE
Experimental Section
Forensic Science, S.A., 21 Divett Place, Adelaide, S.A., 5000, Australia
Hair Sample. Hair was obtained from a 57 year old lead smelter worker with elevated blood lead levels (∼30-40 µg/ dL) living in Pt Pirie, South Australia. The hair was black in color and selected from the top of the head and free of cosmetic treatments. Pt Pirie is the largest smelter of its type in the world, processing lead, silver, gold, copper, zinc, and other metals. Lead in the workplace and the surrounding district is of constant concern. Various programs to monitor the levels of lead pollution are in place and aim to reduce environmental concentrations. Hairs were obtained through the Environmental Health Centre in Pt Pirie, South Australia, by plucking from the scalp using tweezers and storing in aluminum foil. A washing procedure was not used so as to preserve any contaminants and to identify their presence and influence on hair elemental concentrations. While the individual hair studied may not be representative of every other hair from the same individual, its behavior regarding loss and incorporation should be comparable. Scanning Electron Microscopy-Energy Dispersive X-ray Analysis (SEM-EDX). SEM-EDX was applied to investigate any visible surface contamination in the form of particulate matter. Carbon coated samples were analyzed using a Camscan 2-90FE SEM with a 10 mm working distance and 20 kV accelerating voltage. Time-of-Flight-Secondary Ion Mass Spectrometry (ToFSIMS). The outer hair surface was analyzed with ToF-SIMS (Physical Electronics Inc PHI TRIFT II), a nondestructive, highly surface-sensitive technique. A 25 kV Ga+ beam was used for optimal spatial resolution (
