Long Alexandra S, Watson Margaret, Arlt Volker M, White Paul A
Department of Biology, University of Ottawa, Ottawa, Ontario, Canada.
Mechanistic Studies Division, Environmental Health Science and Research Bureau, Environmental and Radiation Health Sciences Directorate, HECSB, Health Canada, Ottawa, Ontario, Canada.
Environ Mol Mutagen. 2016 Aug;57(7):535-45. doi: 10.1002/em.22032. Epub 2016 Jul 30.
Coal tar (CT) is a thick black liquid produced as a by-product of coal carbonization to produce coke or manufactured gas. It is comprised a complex mixture of polycyclic aromatic compounds, including a wide range of polycyclic aromatic hydrocarbons (PAHs), many of which are genotoxic and carcinogenic. CT is used in some pavement sealants (also known as sealcoat), which are applied to pavement in order to seal and beautify the surface. Human exposure is known to occur not only during application, but also as a result of the weathering process, as elevated levels of PAHs have been found in settled house dust in residences adjacent to CT-sealed surfaces. In this study we examined the genotoxicity of an extract of a commercially available CT-based sealcoat in the transgenic Muta™Mouse model. Mice were orally exposed to 3 doses of sealcoat extract daily for 28 days. We evaluated genotoxicity by examining: (1) stable DNA adducts and (2) lacZ mutations in bone marrow, liver, lung, small intestine, and glandular stomach, as well as (3) micronucleated red blood cells. Significant increases were seen for each endpoint and in all tissues. The potency of the response differed across tissues, with the highest frequency of adducts occurring in liver and lung, and the highest frequency of mutations occurring in small intestine. The results of this study are the first demonstration of mammalian genotoxicity following exposure to CT-containing pavement sealcoat. This work provides in vivo evidence to support the contention that there may be adverse health effects in mammals, and potentially in humans, from exposure to coal tar. Environ. Mol. Mutagen. 57:535-545, 2016. © 2016 Her Majesty the Queen in Right of Canada.
煤焦油（CT）是煤炭碳化生产焦炭或煤气时产生的一种浓稠黑色液体。它是多环芳烃化合物的复杂混合物，包括多种多环芳烃（PAH），其中许多具有遗传毒性和致癌性。CT被用于一些路面密封剂（也称为封层），这些密封剂用于路面以密封和美化表面。已知人类不仅在使用过程中会接触到CT，而且由于风化过程也会接触到，因为在靠近CT密封表面的住宅中，沉降的室内灰尘中已发现PAH水平升高。在本研究中，我们在转基因Muta™小鼠模型中检测了一种市售CT基封层提取物的遗传毒性。小鼠每天口服3剂封层提取物，持续28天。我们通过检查以下指标评估遗传毒性：（1）稳定的DNA加合物；（2）骨髓、肝脏、肺、小肠和腺胃中的lacZ突变；以及（3）微核红细胞。在所有组织的每个指标上均观察到显著增加。不同组织的反应强度不同，加合物频率最高的是肝脏和肺，突变频率最高的是小肠。本研究结果首次证明了接触含CT的路面密封剂后哺乳动物的遗传毒性。这项工作提供了体内证据，支持了接触煤焦油可能对哺乳动物乃至人类产生不良健康影响的观点。《环境与分子突变》57:535 - 545，2016年。© 2016年加拿大女王陛下。
