Abstract:
Thermal spray coating is a process in which molten metal is sprayed onto a surface. Little is known about the health effects associated with these aerosols. Sprague-Dawley rats were exposed to aerosols (25 mg/m3 × 4 hr/d × 4 d) generated during thermal spray coating using different consumables [i.e. stainless-steel wire (PMET731), Ni-based wire (PMET885), Zn-based wire (PMET540)]. Control animals received air. Bronchoalveolar lavage was performed at 4 and 30 d post-exposure to assess lung toxicity. The particles were chain-like agglomerates and similar in size (310-378 nm). Inhalation of PMET885 aerosol caused a significant increase in lung injury and inflammation at both time points. Inhalation of PMET540 aerosol caused a slight but significant increase in lung toxicity at 4 but not 30 d. Exposure to PMET731 aerosol had no effect on lung toxicity. Overall, the lung responses were in the order: PMET885≫PMET540 >PMT731. Following a shorter exposure (25 mg/m3 × 4 h/d × 1d), lung burdens of metals from the different aerosols were determined by ICP-AES at 0, 1, 4 and 30 d post-exposure. Zn was cleared from the lungs at the fastest rate with complete clearance by 4 d post-exposure. Ni, Cr, and Mn had similar rates of clearance as nearly half of the deposited metal was cleared by 4 d. A small but significant percentage of each of these metals persisted in the lungs at 30 d. The pulmonary clearance of Fe was difficult to assess because of inherently high levels of Fe in control lungs.
摘要:
热喷涂是将熔融金属喷涂到表面上的工艺。关于与这些气溶胶相关的健康影响知之甚少。Sprague-Dawley大鼠暴露于使用不同耗材热喷涂过程中产生的气溶胶(25mg/m3×4hr/d×4d)[即不锈钢丝(PMET731),镍基导线(PMET885),Zn-basedwire(PMET540)].对照动物接受空气。暴露后4天和30天进行支气管肺泡灌洗以评估肺毒性。颗粒是链状附聚物,尺寸相似(310-378nm)。吸入PMET885气雾剂在两个时间点引起肺损伤和炎症的显著增加。吸入PMET540气雾剂在第4天但不是30天引起肺毒性的轻微但显着增加。暴露于PMET731气雾剂对肺毒性没有影响。总的来说,肺反应顺序为:PMET885PMET540>PMT731。在较短的暴露(25mg/m3×4h/d×1d)后,暴露后0、1、4和30d,通过ICP-AES测定不同气溶胶中金属的肺负荷。暴露后4d,锌以最快的速度从肺部清除,完全清除。Ni,Cr,Mn的清除率相似,因为将近一半的沉积金属在4d内被清除。这些金属中每种金属的一小部分但很大一部分在30d时持续存在于肺中。由于对照肺中固有的高Fe水平,因此难以评估Fe的肺清除率。