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Winter Air Pollution from Domestic Coal Fired Heating in Ulaanbaatar, Mongolia, Is Strongly Associated with a Major Seasonal Cyclic Decrease in Successful Fecundity

Badarch, Jargalsaikhan and Harding, James and Dickinson-Craig, Emma and Azen, Colleen and Ong, Hilary and Hunter, Samantha and Pannaraj, Pia S. and Szepesi, Brigitta and Sereenendorj, Tegshjargal and Davaa, Sumiya and Ochir, Chimedsuren and Warburton, David and Readhead, Carol (2021) Winter Air Pollution from Domestic Coal Fired Heating in Ulaanbaatar, Mongolia, Is Strongly Associated with a Major Seasonal Cyclic Decrease in Successful Fecundity. International Journal of Environmental Research and Public Health, 18 (5). Art. No. 2750. ISSN 1660-4601. PMCID PMC7967474.

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Pollution of the environment is increasing and threatens the health and wellbeing of adults and children around the globe. The impact of air pollution on pulmonary and cardiovascular disease has been well documented, but it also has a deleterious effect on reproductive health. Ulaanbaatar, the capital city of Mongolia, has one of the highest levels of air pollution in the world. During the extreme winters when temperatures routinely fall below −20 °C the level of air pollution can reach 80 times the WHO recommended safe levels. Heating mainly comes from coal, which is burned both in power stations, and in stoves in the traditional Ger housing. We studied the impact of air pollution on conception rates and birth outcomes in Ulaanbaatar using a retrospective analysis of health data collected from the Urguu Maternity hospital in Ulaanbaatar, Mongolia. Daily levels of SO₂, NO₂, PM₁₀, and PM_(2.5) were collected from the government Air Quality Monitoring Stations in Ulaanbaatar for the same period as the study. In January, the month of highest pollution, there is a 3.2-fold decrease in conceptions that lead to the successfully delivered infants compared to October. The seasonal variations in conceptions resulting in live births in this study in Ulaanbaatar are shown to be 2.03 ± 0.20 (10-sigma) times greater than those in the Denmark/North America study of Wesselink et al., 2020. The two obvious differences between Ulaanbaatar and Europe/North America are pollution and temperature both of which are extreme in Ulaanbaatar. The extreme low temperature is mitigated by burning coal, which is the main source of domestic heat especially in the ger districts. This drives the level of pollution so the two are inextricably linked. Infants conceived in the months of June-October had the greatest cumulative PM_(2.5) pollution exposure over total gestation, yet these were also the pregnancies with the lowest PM_(2.5) exposure for the month of conception and three months prior to conception. The delivered-infant conception rate shows a markedly negative association with exposure to PM_(2.5) prior to and during the first month of pregnancy. This overall reduction in fecundity of the population of Ulaanbaatar is therefore a preventable health risk. It is of great consequence that the air pollution in Ulaanbaatar affects health over an entire lifespan including reproductive health. This could be remedied with a clean source of heating.

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Additional Information:© 2021 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license ( Received: 14 December 2020; Accepted: 5 March 2021; Published: 9 March 2021. The authors wish to thank the Mongolian National University of Medical Sciences and the Urguu Maternity Hospital in Ulaanbaatar, Mongolia for ethics approval and access to their de-identified patient records. This research was supported by: an NIH Training program FIC/NIEHS DE43; the Children’s Hospital Los Angeles Global Health Residency Program; The Pasadena Guild of Children’s Hospital Los Angeles; The St Andrew’s Society Los Angeles; and a summer student research stipend to JH from the Keck School of Medicine, University of Southern California. We thank the Statistical core of the Saban Research Institute, Los Angeles for helping with data analysis and statistics. Author Contributions: D.W., the corresponding author, spearheads many studies on the impact of pollution on health in Mongolia. D.W. and J.B. conceived the study and supervised the data collection and provided the initial data analysis. J.H. did the full data analysis and wrote the first draft of the paper. E.D.-C. helped analyze the data and write the final version of the manuscript alongside C.O., C.A. assisted with statistical analysis. H.O., S.H. and P.S.P. assisted with study design and data collection in the field. B.S., T.S., S.D. assisted with data collection, tabulation and analysis. D.W. coordinated the research in the field with J.B., C.R. carried out comparisons with the Wesselink et al., 2020 [1] results, contributed her expertise on human reproduction, and edited and provided comments to the final version of the manuscript. All authors have read and agreed to the published version of the manuscript. This research received no external funding. Institutional Review Board Statement: This study was approved by the Medical Ethical Control Committee of the Urguu Maternity Hospital, Ulaanbaatar, Mongolia. Ethical approval was granted on the 1st meeting of 15th of January 2014 and signed by G. Enkhbayar, head of the committee. Informed Consent Statement: Consent to participate was granted by the IRB at UMH, and the Mongolian National University of Medical Sciences (MNUMS), Ulaanbaatar, Mongolia. This paper describes a NIH IRB type 4 exemption de-identified human subjects project. Data Availability Statement: The data presented in this study are available on request from the corresponding author. The data are not publicly available.
Funding AgencyGrant Number
NIH Predoctoral FellowshipFIC/NIEHS DE43
Children’s Hospital Los AngelesUNSPECIFIED
St. Andrew’s Society Los AngelesUNSPECIFIED
University of Southern CaliforniaUNSPECIFIED
Subject Keywords:winter air pollution; conception; fecundity; Ulaanbaatar Mongolia
Issue or Number:5
PubMed Central ID:PMC7967474
Record Number:CaltechAUTHORS:20210311-130748370
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Official Citation:Badarch, J.; Harding, J.; Dickinson-Craig, E.; Azen, C.; Ong, H.; Hunter, S.; Pannaraj, P.S.; Szepesi, B.; Sereenendorj, T.; Davaa, S.; et al. Winter Air Pollution from Domestic Coal Fired Heating in Ulaanbaatar, Mongolia, Is Strongly Associated with a Major Seasonal Cyclic Decrease in Successful Fecundity. Int. J. Environ. Res. Public Health 2021, 18, 2750.
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:108400
Deposited By: Tony Diaz
Deposited On:12 Mar 2021 19:07
Last Modified:19 Apr 2021 21:21

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