Estimation of exposure to particulate matter in pregnant individuals living in an area of unconventional oil and gas operations: Findings from the EXPERIVA study

ABSTRACT

Northeastern British Columbia (Canada) is an area of oil and gas exploitation, which may result in release of fine (PM_2.5) and inhalable (PM₁₀) particulate matter. The aims of this study were to: 1) apply extrapolation methods to estimate exposure to PM_2.5 and PM₁₀ concentrations among EXPERIVA (Exposures in the Peace River Valley study) participants using air quality data archives; and 2) conduct exploratory analyses to investigate correlation between PM exposure and metrics of oil and gas wells density, proximity, and activity. Gestational exposure to PM_2.5 and PM₁₀ of the EXPERIVA participants (n = 85) was estimated by averaging the concentrations measured at the closest or three closest air monitoring stations during the pregnancy period. Drilling metrics were calculated based upon the density and proximity of conventional and unconventional oil and gas wells to each participant’s residence. Phase-specific metrics were determined for unconventional wells. The correlations (ρ) between exposure to PM_2.5 and PM₁₀ and metrics of well density/proximity were determined using Spearman’s rank correlation test. Estimated PM ambient air concentrations ranged between 4.73 to 12.13 µg/m³ for PM_2.5 and 7.14 to 26.61 µg/m³ for PM₁₀. Conventional wells metrics were more strongly correlated with PM₁₀ estimations (ρ between 0.28 and 0.79). Unconventional wells metrics for all phases were positively correlated with PM_2.5 estimations (ρ between 0.23 and 0.55). These results provide evidence of a correlation between density and proximity of oil and gas wells and estimated PM exposure in the EXPERIVA participants.

KEYWORDS:

• Particulate matter
• oil and gas
• unconventional oil and gas
• gestational exposure

Acknowledgments

We want to thank the participants, the medical clinics as well as the Treaty 8 Tribal Association, the Saulteau First Nations and the West Moberly First Nations for their support and welcoming. We also thank the British Columbia Oil and Gas Commission for their help in identifying relevant oil and gas data, as well as GW Solutions for their expertise and coding support.

Disclosure statement

No potential conflict of interest was reported by the authors.

Data availability statement

The data supporting the findings of this study are available within the article and its Supplementary Material files. We will not make additional exposure data in EXPERIVA participants available to external investigators given restrictions in our research agreements and ethics approval .

Additional information

Funding

This research was funded by a Research Competitiveness Fund from the University of Toronto Scarborough awarded to Élyse Caron-Beaudoin. The EXPERIVA study was conducted in Treaty 8, the traditional territory of the Cree, Saulteau and Dunne-Za people. EXPERIVA was funded through a Project grant from the Canadian Institutes of Health Research (CIHR) (Application ID 390320) awarded to Marc-André Verner and Élyse Caron-Beaudoin. At the time of the EXPERIVA study recruitment, Élyse Caron-Beaudoin was supported through a CIHR postdoctoral fellowship (Funding Reference Number 159262).