Coal smoke, gestational cadmium exposure, and fetal growth

Prabjit Barn; Enkhjargal Gombojav; Chimedsuren Ochir; Buyantushig Boldbaatar; Bolor Beejin; Gerel Naidan; Jargalsaikhan Galsuren; Bayarkhuu Legtseg; Tsogtbaatar Byambaa; Jennifer A Hutcheon; Craig Janes; Patricia A Janssen; Bruce P Lanphear; Lawrence C McCandless; Tim K Takaro; Scott A Venners; Glenys M Webster; Christopher D Palmer; Patrick J Parsons; Ryan W Allen

doi:10.1016/j.envres.2019.108830

Coal smoke, gestational cadmium exposure, and fetal growth

Environ Res. 2019 Dec;179(Pt B):108830. doi: 10.1016/j.envres.2019.108830. Epub 2019 Oct 21.

Authors

Prabjit Barn¹, Enkhjargal Gombojav², Chimedsuren Ochir², Buyantushig Boldbaatar², Bolor Beejin³, Gerel Naidan², Jargalsaikhan Galsuren², Bayarkhuu Legtseg⁴, Tsogtbaatar Byambaa³, Jennifer A Hutcheon⁵, Craig Janes⁶, Patricia A Janssen⁷, Bruce P Lanphear¹, Lawrence C McCandless¹, Tim K Takaro¹, Scott A Venners¹, Glenys M Webster¹, Christopher D Palmer⁸, Patrick J Parsons⁸, Ryan W Allen⁹

Affiliations

¹ Faculty of Health Sciences, Simon Fraser University, 8888 University Drive, Burnaby, V5A 1S6, Canada.
² School of Public Health, Mongolian National University of Medical Sciences, Zorig Street, Ulaanbaatar, 14210, Mongolia.
³ Ministry of Health of Mongolia, Olympic Street-2, Government Building VIII, Sukhbaatar District, Ulaanbaatar, Mongolia.
⁴ Sukhbaatar District Health Center, 11 Horoo, Tsagdaagiin Gudamj, Sukhbaatar District, Ulaanbaatar, Mongolia.
⁵ Faculty of Medicine, Department of Obstetrics & Gynaecology, University of British Columbia, 4500 Oak Street, Vancouver, V6H 2N1, Canada.
⁶ School of Public Health and Health Systems, University of Waterloo, 200 University Avenue West, Waterloo, N2L 3G1, Canada.
⁷ School of Population and Public Health, University of British Columbia, 2206 East Mall, Vancouver, V6T 1Z3, Canada.
⁸ New York State Department of Health, Wadsworth Center, Albany, NY, PO Box 509, 12201, USA; School of Public Health, University at Albany, State University of New York, One University Place, Rensselaer, NY, 12144, USA.
⁹ Faculty of Health Sciences, Simon Fraser University, 8888 University Drive, Burnaby, V5A 1S6, Canada. Electronic address: allenr@sfu.ca.

PMID: 31678728
DOI: 10.1016/j.envres.2019.108830

Abstract

Background: Gestational cadmium exposure may impair fetal growth. Coal smoke has largely been unexplored as a source of cadmium exposure. We investigated the relationship between gestational cadmium exposure and fetal growth, and assessed coal smoke as a potential source of airborne cadmium, among non-smoking pregnant women in Ulaanbaatar, Mongolia, where coal combustion in home heating stoves is a major source of outdoor and indoor air pollution.

Methods: This observational study was nested within the Ulaanbaatar Gestation and Air Pollution Research (UGAAR) study, a randomized controlled trial of portable high efficiency particulate air (HEPA) filter air cleaner use during pregnancy, fetal growth, and early childhood development. We measured third trimester blood cadmium concentrations in 374 out of 465 participants who had a live birth. We used multiple linear and logistic regression to assess the relationships between log₂-transformed maternal blood cadmium concentrations and birth weight, length, head circumference, ponderal index, low birth weight, small for gestational age, and preterm birth in crude and adjusted models. We also evaluated the relationships between log₂-transformed blood cadmium concentrations and the density of coal-burning stoves within 5000 m of each participant's apartment as a proxy of coal smoke emissions from home heating stoves.

Results: The median (25th,75th percentile) blood cadmium concentration was 0.20 (0.15, 0.29) μg/L. A doubling of blood cadmium was associated with a 95 g (95% CI: 34, 155 g) reduction in birth weight in adjusted models. An interquartile range increase in coal stove density (from 3.4 to 4.9 gers/hectare) surrounding participants' apartments was associated with a 12.2% (95% CI: 0.3, 25.6%) increase in blood cadmium concentrations.

Conclusions: Gestational cadmium exposure was associated with reduced birth weight. In settings where coal is a widely used fuel, cadmium may play a role in the putative association between air pollution and impaired fetal growth.

Keywords: Asia; Birth weight; Cadmium; Coal; Mongolia; Pregnancy.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Air Pollutants / toxicity*
Air Pollution / statistics & numerical data
Birth Weight
Cadmium / toxicity*
Child
Child, Preschool
Coal / toxicity*
Female
Fetal Development / drug effects*
Humans
Infant, Newborn
Maternal Exposure / statistics & numerical data
Mongolia
Particulate Matter
Pregnancy

Substances

Air Pollutants
Coal
Particulate Matter
Cadmium