Departments of Environmental Health and Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA.
Department of Environmental Health, Harvard T.H. Chan School of Public Health and MD-PhD Program, Harvard Medical School, Boston, MA 02115, USA.
Int J Environ Res Public Health. 2018 Sep 6;15(9):1939. doi: 10.3390/ijerph15091939.
The implications of environmental contamination on human health in the Niger Delta region of Nigeria remain a topic of growing international public health interest. To better understand ongoing air pollution and initiate remediation efforts, the United Nations Environmental Programme (UNEP) report recommended the monitoring of volatile organic compounds (VOCs) across different media (water, soil, and air) in Ogoniland, an at-risk population in the Niger Delta region of Nigeria. In this pilot study, we measured indoor VOC concentrations in the indoor air of 20 households in Ogale, an Ogoniland community whose groundwater system is contaminated with benzene at levels 900 times the World Health Organization guidelines and evaluated self-reported health conditions and predicted cancer risks and hazards from inhalation exposure to VOCs. We detected higher concentrations of benzene (mean = 25.7 μg/m³, SD = 23.2 μg/m³) and naphthalene (mean = 7.6 μg/m³, SD = 13.8 μg/m³) than has been reported in other regions. Although study participants reported health symptoms consistent with VOC exposure, we were underpowered to detect a significant association between select indoor VOCs and these self-reported health symptoms using univariate logistic regression models. These findings suggest that that the health symptoms reported by participants may be poor proxies for the underlying disease processes associated with adverse health outcomes due to VOC exposure in this community and that the burden of adverse health effects due to VOC exposure may stem from the contaminated groundwater system. We estimated a non-cancer hazard quotient of 3 from exposure to naphthalene and lifetime excess cancer risks from exposure to naphthalene, benzene, p-dichlorobenzene, carbon tetrachloride, and ethylbenzene of 3 × 10, 2 × 10, 6 × 10, 6 × 10, and 1 × 10, respectively. These results exceed common risk benchmarks in the United States, suggesting a need for further studies to characterize VOC exposures, sources, and associated health risks in the Niger Delta.
尼日利亚尼日尔三角洲地区的环境污染对人类健康的影响仍然是国际公共卫生日益关注的话题。为了更好地了解正在发生的空气污染并启动补救措施，联合国环境规划署（UNEP）的报告建议在尼日利亚尼日尔三角洲奥戈尼兰的不同介质（水、土壤和空气）中监测挥发性有机化合物（VOCs）。在这项试点研究中，我们测量了奥加利（Ogale）20 户家庭室内空气中的 VOC 浓度，奥加利是奥戈尼兰社区的一个高危人群，其地下水系统受到苯的污染，含量是世界卫生组织指南的 900 倍，并评估了自我报告的健康状况以及预测癌症风险和因吸入 VOC 而产生的危害。我们检测到苯（平均值=25.7μg/m³，标准差=23.2μg/m³）和萘（平均值=7.6μg/m³，标准差=13.8μg/m³）的浓度高于其他地区的报告值。尽管研究参与者报告的健康症状与 VOC 暴露一致，但我们的能力不足以使用单变量逻辑回归模型检测室内 VOC 与这些自我报告的健康症状之间的显著关联。这些发现表明，由于该社区中 VOC 暴露与不良健康结果相关的潜在疾病过程，参与者报告的健康症状可能是不良的替代指标，并且由于 VOC 暴露而导致的不良健康影响的负担可能源于受污染的地下水系统。我们估计，由于暴露于萘而导致的非癌症危害系数为 3，由于暴露于萘、苯、对二氯苯、四氯化碳和乙苯而导致的终生超额癌症风险分别为 3×10、2×10、6×10、6×10 和 1×10。这些结果超过了美国常见的风险基准，表明需要进一步研究来描述尼日尔三角洲地区 VOC 暴露、来源和相关健康风险。
