Pool B L, Janowsky I, Klein P, Klein R G, Schmezer P, Vogt-Leucht G, Zeller W J
Institute for Toxicology and Chemotherapy, German Cancer Research Center, Heidelberg.
Carcinogenesis. 1988 Jul;9(7):1237-45. doi: 10.1093/carcin/9.7.1237.
This paper describes in vitro studies on the effects of environmental pollutants (SO2/NOx) in biological systems. Basic physical, chemical and biochemical parameters were analyzed to establish the rate of SO2/NOx absorption by the culture medium. It was shown that the pH remains constant for 24 h of exposure to gas concentrations up to 50 p.p.m. The concentration of ions resulting from absorption of each pollutant in the liquid phase is dependent on their concentration in the gas phase and on exposure time. Short exposure times and high gas dosages resulted in similar doses in the medium as long exposure periods and low gas dosages. The activities of a human serum standard (alkaline phosphatase, ALP; aspartate amino transferase, AST; alanine amino transferase, ALT; gamma-glutamyltransferase, gamma-GT; lactate dehydrogenase, LDH) were determined after gaseous exposure to SO2 and NOx. The results revealed a distinct decrease in the activity of LDH after 1, 3 and 5 h exposure to 200 p.p.m. SO2. The effects of the pollutants were assayed in vitro using fetal hamster lung cells (FHLC), rat hepatocytes and the cell line CO60. For the determination of toxic effects, it was shown that the plating efficiency was a more sensitive parameter than the assay for trypan blue exclusion. Toxicity indicated as an increase of LDH leakage was not observed from FHLC in culture. Instead, a decrease of LDH was found following SO2 exposition. This decrease was similar to that observed for the human serum standard. The induction of DNA single-strand breaks was determined as a measure of genotoxic effects. SO2 application decreased the rate of DNA single-strand breaks induced by N-nitroso-acetoxymethyl-methylamine in both FHLC and in rat hepatocytes. SO2 or NOx treatment of CO60 cells for 1 h did not result in the induction of DNA amplification. HSO3- added directly to the medium as the sodium salt, however, distinctly induced the amplification of SV40 DNA. The amplification rates induced by benzo[a]pyrene or dimethylbenzanthracene were neither influenced by SO2, NOx nor HSO3-. An additive effect of HSO3- with either benzo[a]pyrene or dimethylbenzanthracene for this biological parameter was therefore not observed.
本文描述了环境污染物（二氧化硫/氮氧化物）对生物系统影响的体外研究。分析了基本的物理、化学和生化参数，以确定培养基对二氧化硫/氮氧化物的吸收速率。结果表明，在暴露于浓度高达50 ppm的气体24小时内，pH值保持恒定。液相中每种污染物吸收产生的离子浓度取决于其在气相中的浓度和暴露时间。短暴露时间和高气体剂量与长暴露时间和低气体剂量在培养基中产生的剂量相似。在气态暴露于二氧化硫和氮氧化物后，测定了人血清标准物（碱性磷酸酶、ALP；天冬氨酸氨基转移酶、AST；丙氨酸氨基转移酶、ALT；γ-谷氨酰转移酶、γ-GT；乳酸脱氢酶、LDH）的活性。结果显示，暴露于200 ppm二氧化硫1、3和5小时后，LDH活性明显降低。使用胎仓鼠肺细胞（FHLC）、大鼠肝细胞和CO60细胞系在体外测定了污染物的影响。为了确定毒性作用，结果表明，接种效率是比台盼蓝排斥试验更敏感的参数。在培养的FHLC中未观察到以LDH泄漏增加表示的毒性。相反，二氧化硫暴露后发现LDH减少。这种减少与在人血清标准物中观察到的相似。测定DNA单链断裂的诱导作为遗传毒性作用的指标。在FHLC和大鼠肝细胞中，二氧化硫的应用均降低了N-亚硝基-乙酰氧基甲基-甲胺诱导的DNA单链断裂率。用二氧化硫或氮氧化物处理CO60细胞1小时未导致DNA扩增的诱导。然而，直接以钠盐形式添加到培养基中的亚硫酸氢根明显诱导了SV40 DNA的扩增。苯并[a]芘或二甲基苯并蒽诱导的扩增率既不受二氧化硫、氮氧化物也不受亚硫酸氢根的影响。因此，未观察到亚硫酸氢根与苯并[a]芘或二甲基苯并蒽对该生物学参数的相加作用。
