Oller Adriana R, Cappellini Danielle, Henderson Rayetta G, Bates Hudson K
NiPERA, 2605 Meridian Parkway, Suite 200, Durham, NC 27713, USA.
J Environ Monit. 2009 Apr;11(4):823-9. doi: 10.1039/b820926j. Epub 2009 Feb 11.
Chemical speciation of workplace nickel exposures is critical because nickel-containing substances often differ in toxicological properties. Exposure matrices based on leaching methods have been used to ascertain which chemical forms of nickel are primarily associated with adverse respiratory effects after inhalation. Misjudgments in the relative proportion of each of the main fractions of nickel in workplace exposures could translate into possible misattributions of risk to the various forms of nickel. This preliminary study looked at the efficiency of the first step of the Zatka leaching method for accurately assessing the 'water-soluble' fraction of several substances present in nickel production operations, compared to leaching in synthetic lung fluid. The present results demonstrate that for nickel sulfate or chloride, the current Zatka solution is adequate to assess the 'water-soluble' fraction. However, when sparingly water-soluble compounds like nickel carbonates or water-insoluble substances like nickel subsulfide and fine metallic nickel powders are present, the first step of the Zatka method can greatly over estimate the amount of nickel that could be released in pure water. In contrast, the releases of nickel from nickel carbonate, nickel subsulfide, and nickel metal powders in pure water are consistent with their releases in synthetic lung fluid, indicating that deionized water is a better leaching solution to estimate the biologically relevant 'water-soluble' nickel fraction of workplace exposures. Exposure matrices relying mostly on the Zatka speciation method to estimate the main forms of nickel need to be re-evaluated to account for any possible misattributions of risk.
工作场所镍暴露的化学形态至关重要，因为含镍物质的毒理学特性往往存在差异。基于浸出方法的暴露矩阵已被用于确定吸入后与不良呼吸影响主要相关的镍的化学形态。工作场所暴露中镍各主要组分相对比例的误判可能会导致对各种镍形态风险的错误归因。本初步研究考察了扎特卡浸出法第一步在准确评估镍生产作业中几种物质的“水溶性”组分方面的效率，并与在合成肺液中的浸出情况进行了比较。目前的结果表明，对于硫酸镍或氯化镍，当前的扎特卡溶液足以评估“水溶性”组分。然而，当存在碳酸镍等微溶于水的化合物或硫化亚镍和细金属镍粉等不溶于水的物质时，扎特卡方法的第一步可能会极大地高估纯水中可能释放的镍量。相比之下，碳酸镍、硫化亚镍和镍金属粉在纯水中的镍释放量与它们在合成肺液中的释放量一致，这表明去离子水是一种更好的浸出溶液，可用于估计工作场所暴露中具有生物学相关性的“水溶性”镍组分。主要依靠扎特卡形态分析方法来估计镍主要形态的暴露矩阵需要重新评估，以考虑任何可能的风险错误归因。
