Flessel P, Quintana P J, Hooper K
Air and Industrial Hygiene Laboratory, California Department of Health Services, Berkeley 94704.
Environ Mol Mutagen. 1993;22(1):7-17. doi: 10.1002/em.2850220104.
Mammalian in vivo and in vitro studies of technical or commercial grade malathion and its metabolite malaoxon show a pattern of induction of chromosome damage, as measured by chromosome aberrations, sister chromatid exchanges, and micronuclei. Experiments with purified (> 99%) malathion gave weak or negative results. In contrast to the cytogenetic effects of technical grade malathion, responses in gene mutation assays were generally negative except for malaoxon, which was positive for mammalian gene mutations in both tested instances. This result also could be a consequence of chromosome level changes, however. Dermal exposure, a common human route, caused cytogenetic damage in test animals at doses near those producing positive results by intraperitoneal injection. Workers who apply technical grade malathion and other pesticides have higher levels of chromosomal damage than unexposed individuals. Because of the inactivity of malathion mixtures in gene mutation assays, malathion has been thought to be of little genotoxic concern. However, the pattern of chromosome damage in animals and mammalian cells in culture (including human) indicates that technical grade malathion and its components have not been adequately studied for genotoxic potential in humans.
对工业级或商业级马拉硫磷及其代谢产物马拉氧磷进行的哺乳动物体内和体外研究显示，通过染色体畸变、姐妹染色单体交换和微核检测，存在诱导染色体损伤的情况。使用纯化的（>99%）马拉硫磷进行的实验结果微弱或呈阴性。与工业级马拉硫磷的细胞遗传学效应相反，除马拉氧磷外，基因突变检测的反应通常为阴性，而马拉氧磷在两个测试实例中对哺乳动物基因突变均呈阳性。不过，这一结果也可能是染色体水平变化的结果。经皮暴露是人类常见的接触途径，在测试动物中，接近腹腔注射产生阳性结果的剂量会导致细胞遗传学损伤。施用工业级马拉硫磷和其他农药的工人的染色体损伤水平高于未接触者。由于马拉硫磷混合物在基因突变检测中无活性，人们一直认为马拉硫磷几乎不存在遗传毒性问题。然而，动物和培养的哺乳动物细胞（包括人类细胞）中的染色体损伤模式表明，工业级马拉硫磷及其成分对人类遗传毒性潜力的研究尚不充分。
