Gordon T, Harkema J R
Institute of Environmental Medicine, New York University Medical Center, Tuxedo, New York 10987, USA.
Fundam Appl Toxicol. 1995 Dec;28(2):274-82. doi: 10.1006/faat.1995.1168.
Occupational exposure to microbial-contaminated machining fluids is associated with a variety of adverse pulmonary effects including chronic bronchitis and increased sputum production. We have previously demonstrated in F344 rats that inhaled endotoxin can increase the amount of stored intraepithelial mucosubstances (Vs) in the respiratory tract. The purpose of the present study was to examine the effect of endotoxin-contaminated machining fluid aerosols on mucous production. Rats were exposed to aerosols of pyrogen-free water, 1 or 10 mg/m3 used machining fluid, or 10 mg/m3 unused machining fluid for 3 hr/day for 3 days. Twenty-four hours after the final exposure, right lung lobes were lavaged and the nasal cavity and left lung were fixed in formalin. The amount of Alcian blue/periodic acid-Schiff-stained mucosubstances was determined by morphometry. Exposure to 10 mg/m3 used machining fluid (equivalent to 0.8 micrograms/m3 endotoxin) produced a significant increase in Vs in the epithelial lining of both the nasal septum and intrapulmonary airways. These changes in Vs were accompanied by a significant increase in total cells and neutrophils in the lavage fluid. No changes in stored mucosubstances or lavage parameters were found in animals exposed to 1 mg/m3 used machining fluid aerosols. A significant increase in Vs was observed in the nasal septum but not in the intrapulmonary airways of animals exposed to 10 mg/m3 unused machining fluids (no measurable endotoxin). These results suggest that in addition to endotoxin, nonendotoxin components of machining fluids may contribute to the increase in sputum and chronic bronchitis reported for workers exposed to machining fluid aerosols.
职业接触受微生物污染的加工液与多种不良肺部效应有关，包括慢性支气管炎和痰液分泌增加。我们之前在F344大鼠中证明，吸入内毒素可增加呼吸道上皮内储存的黏液物质（Vs）的量。本研究的目的是检查受内毒素污染的加工液气溶胶对黏液分泌的影响。将大鼠每天暴露于无热原水、1或10 mg/m³ 使用过的加工液或10 mg/m³ 未使用过的加工液的气溶胶中，持续3小时，共3天。最后一次暴露后24小时，对右肺叶进行灌洗，并将鼻腔和左肺固定在福尔马林中。通过形态计量学确定阿尔辛蓝/过碘酸希夫染色的黏液物质的量。暴露于10 mg/m³ 使用过的加工液（相当于0.8微克/m³ 内毒素）会导致鼻中隔和肺内气道上皮衬里中的Vs显著增加。Vs的这些变化伴随着灌洗液中总细胞和中性粒细胞的显著增加。暴露于1 mg/m³ 使用过的加工液气溶胶的动物中，储存的黏液物质或灌洗参数没有变化。在暴露于10 mg/m³ 未使用过的加工液（无可测量的内毒素）的动物的鼻中隔中观察到Vs显著增加，但在肺内气道中未观察到。这些结果表明，除内毒素外，加工液的非内毒素成分可能导致接触加工液气溶胶的工人痰液增加和慢性支气管炎。
