Stefaniak Aleksandr B, Harvey Christopher J, Virji M Abbas, Day Gregory A
National Institute for Occupational Safety and Health, Centers for Disease Control and Prevention, Mailstop H-2800, Morgantown, WV 26505, USA.
J Environ Monit. 2010 Oct 6;12(10):1815-22. doi: 10.1039/c0em00269k. Epub 2010 Aug 23.
Skin exposure to cobalt-containing materials can cause systemic immune sensitization and upon repeat contact, elicitation of allergic contact dermatitis (ACD). Data on cobalt dissolution rates are needed to calculate uptake through skin and for development of models to understand risk of sensitization or dermatitis. The purpose of this research was to measure the dissolution kinetics of feedstock and process-sampled powders encountered in the production of hard metal alloys using artificial sweat. The physicochemical properties of each material were characterized prior to evaluation of dissolution behavior. Variations in artificial sweat solvent pH and chemistry were used to understand critical factors in dissolution. Dissolution of cobalt, tungsten, and tungsten carbide was often biphasic with the initial rapid phase being up to three orders of magnitude faster than the latter long-term phase. Artificial sweat pH did not influence dissolution of cobalt or tungsten carbide. Solvent composition had little influence on observed dissolution rates; however, vitamin E suppressed the dissolution of cobalt and tungsten carbide from sintered particles obtained from a chamfer grinder. There was no effect of particle size on dissolution of feedstock cobalt, tungsten, tungsten carbide, and admixture powders. Particle physicochemical properties influenced observed dissolution rates with more cobalt and tungsten carbide dissolving from chamfer grinder particles compared to the feedstock powders or admixture powder. Calculations using the observed dissolution rates revealed that skin exposure concentrations were similar to concentrations known to induce cobalt sensitization and elicit ACD. Observed dissolution rates for cobalt in artificial sweat indicate that dermal uptake may be sufficient to induce cobalt sensitization and allergic dermatitis.
皮肤接触含钴材料可导致全身免疫致敏，再次接触时会引发过敏性接触性皮炎（ACD）。需要钴的溶解速率数据来计算经皮肤的摄入量，并用于建立模型以了解致敏或皮炎风险。本研究的目的是使用人工汗液测量硬质合金生产中遇到的原料粉末和工艺采样粉末的溶解动力学。在评估溶解行为之前，对每种材料的物理化学性质进行了表征。利用人工汗液溶剂pH值和化学组成的变化来了解溶解的关键因素。钴、钨和碳化钨的溶解通常是双相的，初始快速阶段比后期长期阶段快三个数量级。人工汗液pH值不影响钴或碳化钨的溶解。溶剂组成对观察到的溶解速率影响很小；然而，维生素E抑制了从倒角研磨机获得的烧结颗粒中钴和碳化钨的溶解。粒径对原料钴、钨、碳化钨和混合粉末的溶解没有影响。颗粒的物理化学性质影响观察到的溶解速率，与原料粉末或混合粉末相比，倒角研磨机颗粒中溶解出的钴和碳化钨更多。使用观察到的溶解速率进行的计算表明，皮肤接触浓度与已知可诱导钴致敏和引发ACD的浓度相似。人工汗液中钴的观察到的溶解速率表明，经皮吸收可能足以诱导钴致敏和过敏性皮炎。
