Iwado H, Koyano M, Goto S, Kira S, Hayatsu H
Faculty of Pharmaceutical Sciences, Okayama University, Japan.
Mutat Res. 1994 Oct;322(4):329-39. doi: 10.1016/0165-1218(94)90109-0.
Previous studies on several samples of urban air-borne particulates showed that the long-chain fatty acids present in these samples can interfere with the measurement of mutagenicity of the particulates with the Salmonella assay. To explore whether this phenomenon is a general, fatty acid contents and the mutagenicity (with Salmonella typhimurium TA98 without S9) were measured for 34 particulate samples collected in the cities of Okayama and Tokyo over a period of 1 year. Palmitic, stearic, oleic and linoleic acids were found in all these samples in this order of amount, and their interference on mutagenicity measurement was eminent, particularly at high doses of the sample. With the use of blue cotton extraction, the mutagenic components can be freed from most of these antimutagenic factors. Significant correlation was found between the number of particulates and the mutagenicity per unit volume of the air. Eight polycyclic aromatic hydrocarbon compounds, including benzo[alpha]pyrene were quantified for these 34 particulate samples. Their contents were too small to account for the observed mutagenicity, suggesting that other polycyclic compounds, possibly involving nitro aromatics, were responsible for the mutagenicity observed. No remarkable differences were noted between Okayama and Tokyo in fatty acid contents, mutagenicity or polycyclic aromatic-hydrocarbon contents of the samples.
先前对多个城市空气悬浮颗粒物样本的研究表明，这些样本中存在的长链脂肪酸会干扰用沙门氏菌试验测定颗粒物的致突变性。为了探究这种现象是否普遍存在，对冈山和东京两市在1年时间内收集的34个颗粒物样本测定了脂肪酸含量和致突变性（采用鼠伤寒沙门氏菌TA98菌株，无S9）。在所有这些样本中均发现了棕榈酸、硬脂酸、油酸和亚油酸，其含量依次递减，并且它们对致突变性测定的干扰显著，尤其是在高剂量样本时。通过使用蓝棉萃取法，可以去除大部分这些抗诱变因子，从而分离出致突变成分。发现颗粒物数量与单位体积空气中的致突变性之间存在显著相关性。对这34个颗粒物样本定量分析了包括苯并[a]芘在内的8种多环芳烃化合物。其含量过低，无法解释所观察到的致突变性，这表明可能涉及硝基芳烃的其他多环化合物是所观察到的致突变性的原因。在样本的脂肪酸含量、致突变性或多环芳烃含量方面，冈山和东京之间未发现显著差异。
