Characterisation of nickel industry workplace aerosols by particle size and nickel species

The aim of this project was to collect data on nickel aerosol chemical speciation and particle size distribution in two large-scale nickel production facilities. Personal and fixed point samples were collected to assess airborne dust concentrations, nickel concentrations, nickel speciation and aerosol particle size distributions using IOM and Marple cascade impactor sampling heads. A total of 46 (30 personal and 16 static) inhalable samples and 28 (18 personal and 10 static) cascade impactor samples were obtained. All samples were analysed gravimetrically; the static inhalable samples were analysed for nickel species, whilst the remaining samples were analysed for total nickel. Inhalable dust and nickel concentrations were below the relevant UK Workplace Exposure Limits, although some high exposure levels were observed in the raw materials area of Site One and conversion and furnace areas of Site Two. In the raw materials and electrolysis areas of Site One and the furnace area in Site Two, the vast majority of the dust concentration consisted of particles greater than 10�m. At Site Two there was evidence in the rotary kilns area of a greater proportion of finer particles being present. Although nickel speciation analysis was undertaken and reported, management at both Sites have raised concerns regarding their validity, in particular the sulfidic nickel species results, when considering the composition of the raw materials used and the final products.The findings of this research program will inform the risk assessment process for nickel exposure in this industry. “”