Department of Epidemiology and Biostatistics, School of Public Health, Texas A&M University, USA.
Department of Epidemiology and Biostatistics, School of Public Health, Texas A&M University, USA.
Environ Pollut. 2019 Aug;251:128-136. doi: 10.1016/j.envpol.2019.04.016. Epub 2019 Apr 6.
Thousands of chemicals exist in hydraulic-fracturing (HF) fluids and wastewater from unconventional oil gas development. The carcinogenicity of these chemicals in HF fluids and wastewater has never been systematically evaluated.
In this study, we assessed the carcinogenicity of 1,173 HF-related chemicals in the HF chemical data from the US Environmental Protection Agency (EPA).
We linked the HF chemical data with the agent classification data from the International Agency for Research on Cancer (IARC) at the World Health Organization (WHO) (N = 998 chemicals) to evaluate human carcinogenic risk of the chemicals and with the Carcinogenic Potency Database (CPDB) from Toxnet (N = 1,534 chemicals) to evaluate potential carcinogenicity of the chemicals.
The Chemical Abstract Service Registry Numbers (CASRNs) for chemicals were used for data linkage. Among 1,173 chemicals, 1,039 were identified only in HF fluids, 97 only in wastewater, and 37 in both. Compared with IARC, we found information of 104 chemicals, and 48 of them may have potentially carcinogenic risk to human, among which 14 are definitely carcinogenic, 7 probably carcinogenic, and 27 possibly carcinogenic. Using the CPDB data, it suggests that 66 chemicals are potentially carcinogenic based on rats and mouse models.
Conclusions Our evaluation suggests that exposure to some chemicals in HF fluids and wastewater may increase cancer risk, and the identified chemicals could be selected as the priority list for drinking water exposure assessment or cancer-related health studies.
在非常规油气开发的水力压裂（HF）液和废水中存在数千种化学物质。这些化学物质在 HF 液和废水中的致癌性从未被系统评估过。
在这项研究中，我们评估了美国环境保护署（EPA）HF 化学数据中 1173 种与 HF 相关的化学物质的致癌性。
我们将 HF 化学数据与世界卫生组织（WHO）国际癌症研究机构（IARC）的代理分类数据（N=998 种化学物质）相联系，以评估这些化学物质对人类的致癌风险，并与 Toxnet 的致癌潜能数据库（CPDB）（N=1534 种化学物质）相联系，以评估这些化学物质的潜在致癌性。
使用化学品的化学文摘服务登记号（CASRN）进行数据链接。在 1173 种化学物质中，有 1039 种仅在 HF 液中被识别，97 种仅在废水中被识别，37 种在两者中都被识别。与 IARC 相比，我们发现了 104 种化学物质的信息，其中 48 种可能对人类具有潜在致癌风险，其中 14 种是肯定致癌的，7 种是可能致癌的，27 种是可能致癌的。使用 CPDB 数据，根据大鼠和小鼠模型，有 66 种化学物质可能具有致癌性。
我们的评估表明，接触 HF 液和废水中的一些化学物质可能会增加癌症风险，所识别的化学物质可以被选为饮用水暴露评估或癌症相关健康研究的优先清单。
