Daley Coreen, Doris Miranda, Verner Marc-André, Zalzal Jad, Chesnaux Romain, Minet Laura, Kang Mary, MacLean Heather L, Hatzopoulou Marianne, Owens-Beek Naomi, Caron-Beaudoin Élyse
Department of Physical and Environmental Sciences, University of Toronto Scarborough, Toronto, Ontario, Canada.
Civil and Mineral Engineering, University of Toronto, Toronto, Ontario, Canada.
Int J Hyg Environ Health. 2025 Jan;263:114462. doi: 10.1016/j.ijheh.2024.114462. Epub 2024 Sep 17.
In a previous study located in Northeastern British Columbia (Canada), we observed associations between density and proximity of oil and gas wells and indoor air concentrations of certain volatile organic compounds (VOCs). Whether conventional or unconventional well types and phases of unconventional development contribute to these associations remains unknown.
To investigate the associations between proximity-based metrics for conventional and unconventional wells and measured indoor air VOC concentrations in the Exposures in the Peace River Valley (EXPERIVA) study samples.
Eighty-four pregnant individuals participated in EXPERIVA. Passive indoor air samplers were analyzed for 47 VOCs. Oil and gas well legacy data were sourced from the British Columbia Energy Regulator. For each participant's home, 5 km, 10 km and no buffer distances were delineated, then density and Inverse Distance Square Weighted (IDW) metrics were calculated to estimate exposure to conventional and unconventional wells during pregnancy and the VOC measurement period. Multiple linear regression models were used to test for associations between the well exposure metrics and indoor air VOCs. For exposure metrics with >30% participants having a value of 0, we dichotomized exposure (0 vs. >0) and performed ANOVAs to assess differences in mean VOCs concentrations.
Analyses indicated that: 1) conventional well density and IDW metrics were positively associated with indoor air acetone and decanal; 2) unconventional well density and IDW metrics were positively associated with indoor air chloroform and decamethylcyclopentasiloxane, and negatively associated with decanal; 3) drilling specific IDW metrics for unconventional wells were positively associated with indoor air chloroform.
Our analysis revealed that the association between the exposure metrics and indoor air acetone could be attributed to conventional wells and the association between exposure metrics and indoor air chloroform and decamethylcyclopentasiloxane could be attributed to unconventional wells.
在之前一项位于加拿大不列颠哥伦比亚省东北部的研究中，我们观察到油气井的密度和距离与某些挥发性有机化合物（VOCs）的室内空气浓度之间存在关联。传统或非常规井类型以及非常规开发阶段是否导致了这些关联尚不清楚。
在和平河谷暴露情况（EXPERIVA）研究样本中，调查基于距离的传统和非常规井指标与实测室内空气VOC浓度之间的关联。
84名孕妇参与了EXPERIVA研究。对被动式室内空气采样器进行了47种VOCs的分析。油气井遗留数据来自不列颠哥伦比亚省能源监管机构。对于每位参与者的家，划定了5公里、10公里和无缓冲距离，然后计算密度和反距离平方加权（IDW）指标，以估计孕期和VOC测量期间接触传统和非常规井的情况。使用多元线性回归模型测试井暴露指标与室内空气VOCs之间的关联。对于超过30%参与者值为0的暴露指标，我们将暴露情况二分法（0与>0）并进行方差分析以评估平均VOCs浓度的差异。
分析表明：1）传统井密度和IDW指标与室内空气丙酮和癸醛呈正相关；2）非常规井密度和IDW指标与室内空气氯仿和十甲基环五硅氧烷呈正相关，与癸醛呈负相关；3）非常规井的钻井特定IDW指标与室内空气氯仿呈正相关。
我们的分析表明，暴露指标与室内空气丙酮之间的关联可归因于传统井，暴露指标与室内空气氯仿和十甲基环五硅氧烷之间的关联可归因于非常规井。
