A number of cases of respiratory sensitization to soluble platinum have arisen in the U.K. over the last few years, despite measured 8 h TWA exposure levels below the current long-term exposure limit in most cases. One possible cause of sensitization may be as a result of high exposures over short periods. Short-term sampling has been hampered by inadequate sampling and analysis techniques. This investigation has used two types of personal inhalable sampler, with ICPMS analysis, to take 15 min TWA soluble platinum exposure measurements at three sites. The lower detection limit for soluble platinum salts was approximately 0.01 microgram m-3 for 15 min samples, allowing exposures two orders of magnitude below the exposure limit to be measured. It was found that the majority of short-term exposure levels were significantly below 0.006 mg m-3. No evidence was found for altered work practices during sampling, indicating that either sensitization is occurring at airborne exposure levels below the exposure limit, or there is an alternate route of exposure.

The Health and Safety Executive (HSE) publish methods for sampling and analysis of workplace air in its 'Methods for the Determination of Hazardous Substances' (MDHS) series. MDHS 42, 'Nickel and Inorganic Compounds of Nickel in Air', which was published in 1984, describes a laboratory method using FAAS. In 1992 HSE revised the exposure limits for nickel in air. Three maximum exposure limits (eight-hour time-weighted averages) were set at 0.5,O.l and 0.5 mg m-3for nickel, soluble and insoluble nickel compounds, respectively. Soluble nickel compounds were defined as those with a solubility greater than 10% by mass in water at 20 "C. It was decided that this was an appropriate time to review MDHS 42 and this paper describes work carried out to develop and validate a revised method. New sample dissolution procedures have been included in the revised MDHS and the method has been extended to include ETAAS. The effectiveness of procedures was tested by analysing a range of dusts typically found in the working environment. Method performance was determined by taking doped fdters through the described procedures, and this was assessed for compliance with the Comit6 Europtkn de Normalisation European Standard EN 482, 'Workplace Atmospheres-General Requirements for the Performance of Procedures for the Measurement of Chemical Agents'.

Inhalation exposure at seven UK secondary aluminium smelters was investigated to quantify the main exposures and identify their sources. The substances monitored were gases (carbon monoxide, hydrogen sulphide and nitrogen dioxide), total inhalable dust, metals, ammonia, polycyclic aromatic hydrocarbons (PAHs), particulate fluoride salts and acids. The results showed that people were exposed to a range of workplace air pollutants. Personal exposure results for total inhalable dust were between 700 and 5600 microg x m(-3) and the maximum personal exposure result for particulate fluoride salts was 690 microg x m(-3) (as F). The maximum aluminium, total PAH and lead personal exposure results were 900, 19 and 18 microg x m(-3) respectively. The average proportion of aluminium in total inhalable dust samples was 13% and rotary furnace processes generated the most dust. Particulate fluoride salt exposure was more widespread than hydrofluoric acid exposure. The source of the salt exposure was fluoride containing fluxes. The lead exposure source was lead solder contamination in the furnace charge.

No abstract