University of Mississippi eGrove Honors College (Sally McDonnell Barksdale Honors Theses Honors College) Spring 5-1-2021 Fine Particulate Matter and Low Weight Births in Mexico City, Mexico Kennedy Cohn University of Mississippi Follow this and additional works at: https://egrove.olemiss.edu/hon_thesis Part of the Environmental Public Health Commons, Environmental Studies Commons, Latin American Studies Commons, and the Maternal and Child Health Commons Recommended Citation Cohn, Kennedy, "Fine Particulate Matter and Low Weight Births in Mexico City, Mexico" (2021). Honors Theses. 1827. https://egrove.olemiss.edu/hon_thesis/1827 This Undergraduate Thesis is brought to you for free and open access by the Honors College (Sally McDonnell Barksdale Honors College) at eGrove. It has been accepted for inclusion in Honors Theses by an authorized administrator of eGrove. For more information, please contact [email protected]. FINE PARTICULATE MATTER AND LOW WEIGHT BIRTHS IN MEXICO CITY, MEXICO by Kennedy Cohn A thesis presented in partial fulfillment of the requirements for completion Of the Bachelor of Arts degree in International Studies Croft Institute for International Studies Sally McDonnell Barksdale Honors College The University of Mississippi University, Mississippi May 2021 Approved by Advisor: Dr. Kate Centellas Reader: Dr. Oliver Dinius Reader: Dr. Courtney Roper 1 © 2021 Kennedy Cohn ALL RIGHTS RESERVED 2 ABSTRACT Fine particulate matter (PM2.5) exposure has been associated with several negative health consequences, and recent studies suggest a potential relationship between PM2.5 exposure and adverse birth outcomes, including low birth weight (LBW). This thesis investigated a potential relationship between fine particulate matter concentration and low birth weight in Mexico City, Mexico between 2008-2016. Maternal pollution exposure was estimated at the city-wide level by averaging PM2.5 measurements from various monitoring stations. Birth weight was collected from the SINAC database. Logistic regression models were run for different temporal scales (by trimester, and 10-month periods); however, there were no significant relationships found between PM2.5 concentration and low birth weight. This study was limited in many ways. More research is needed to determine if specific PM2.5 components are generated negative health consequences rather than mere concentration. 3 TABLE OF CONTENTS CHAPTER 1 - INTRODUCTION ................................................................................................. 8 1.1 CONCEPTUALIZATION OF AIR POLLUTION ........................................................................ 9 1.2 LATIN AMERICA .............................................................................................................. 12 1.3 CONCLUSION ................................................................................................................... 17 CHAPTER 2 - BACKGROUND .................................................................................................. 19 2.1 AIR POLLUTION INTRODUCTION ..................................................................................... 19 2.1.1 Fine Particulate Matter (PM2.5) ........................................................................... 20 2.2 LITERATURE REVIEW OF STUDIES LINKING PM2.5 AND ADVERSE BIRTH OUTCOMES .... 22 2.2.1 PM2.5 Exposure and Low Birth Weight Studies: Methodological Variation ....... 23 2.2.2 Variation in Exposure Period ................................................................................ 25 2.2.3 Potential Mechanisms and Animal Studies ............................................................ 26 2.3 CONCLUSION ................................................................................................................... 28 CHAPTER 3 - MEXICO CITY ................................................................................................... 30 3.1 INTRODUCTION ................................................................................................................ 30 3.2 PRONE TO POLLUTION? ................................................................................................... 31 3.2.1 Geographical Features Contributing to Pollution ................................................ 33 3.3 AIR POLLUTION MITIGATION AND CURRENT CONDITIONS ............................................. 34 3.4 MEXICO CITY AS A CASE STUDY .................................................................................... 37 CHAPTER 4 - RESEARCH DESIGN ......................................................................................... 41 4.1 HYPOTHESIS .................................................................................................................... 41 4.2 METHODOLOGY ............................................................................................................... 41 4.2.1 Air Pollution: PM2.5 ............................................................................................... 41 4.2.2 Birth Weight ........................................................................................................... 44 4.2.3 Sample Population ................................................................................................. 45 4.2.4 Statistical Analysis ................................................................................................. 47 4.3 LIMITATIONS ................................................................................................................... 47 CHAPTER 5 - RESULTS AND DISCUSSION .......................................................................... 49 5.1 OVERVIEW ....................................................................................................................... 49 5.2 BIRTH DATA .................................................................................................................... 49 4 5.3 AIR POLLUTION DATA ..................................................................................................... 52 5.4 STATISTICAL ANALYSIS .................................................................................................. 54 5.5 DISCUSSION ..................................................................................................................... 57 CHAPTER 6 - CONCLUSION .................................................................................................... 61 CHAPTER 7 - REFERENCES .................................................................................................... 63 5 LIST OF FIGURES AND TABLES FIGURE 1- Modelled PM2.5 Levels (PAHO)………………………………………..12 FIGURE 2- Annual Mean PM2.5 Concentration at Latin American Cities …………15 FIGURE 3- Locations of PM2.5 Monitoring Stations and Average Concentrations 2008-2013……………………………………………...…………….17 FIGURE 4- Contribution of PM2.5 by Various Sectors………………………………32 FIGURE 5- PM2.5 from Fossil Fuel Combustion…………………………….……....37 FIGURE 6- Frequency of Births by Weight………………………………….......….50 FIGURE 7- PM2.5 Averages by Trimester…………………………………….……..53 FIGURE 8- 10-Month Average PM2.5 Concentration………………………………..54 TABLE 1- Stations from Which Measurements Were Collected, Including Number of Valid Measurements and Invalid Measurements…………………….43 TABLE 2- Control Variable Coding……………………………………………..…..46 TABLE 3- Characteristics of Study Births…………………………………………..51 TABLE 4- Odds Ratio By Various Exposure Periods (Model 1, Unadjusted) …..…56 TABLE 5- Odds Ratio By Various Exposure Periods (Model 2, Adjusted)………...57 6 ABBREVIATIONS ABO Adverse Birth Outcome AMIA Mexican Vehicle Manufacturer’s Association AQG Air Quality Guidelines CAA Clean Air Act CDMX Mexico City CI Confidence Interval EPA Environmental Protection Agency (U.S.) GDP Gross Domestic Product HDI Human Development Index ICAPPO The International Collaboration on Air Pollution and Pregnancy Outcomes IT Interim Target LAC Latin America and Caribbean LBW Low Birth Weight NOM Normas Oficiales Mexicanas OEEC Organization for European Economic Control OR Odds Ratio PAH Polycyclic Aromatic Hydrocarbon PAHO Pan American Health Organization PM Particulate Matter PM2.5 Fine Particulate Matter (<2.5µm) PM10 Coarse Particulate Matter (<10µm) PTB Pre-Term Birth 7 RAMA La Red Automática de Monitoreo Atmosférico REDDA La Red de Depósito Atmosférico REDMA La Red Manual de Monitoreo Atmosférico REDMET La Red de Meteorología y Radiación Solar ROS Reactive Oxygen Species SES Socioeconomic Status SGA Small for Gestational Age SIMAT El Sistema de Monitoreo Atmosférico SINAC El Subsistema de Información sobre Nacimientos WHO World Health Organization 8 Chapter 1 - Introduction Ambient air pollution is a global health problem that affects millions of people by producing a multitude of adverse health consequences. In 2016, over 91% of the world’s population lived in cities that did not comply with the World Health Organization (WHO) air quality guidelines. (WHO, n.d.). That same year over 4.2 million premature deaths were attributed to ambient air pollution, which has been shown to cause cardiovascular disease, respiratory disease, and cancers. (WHO, n.d.). In addition to being a widespread phenomenon, recent literature has shown that air pollution has the ability to produce transgenerational effects. Pregnant women who are exposed to various types of air pollution potentially expose the fetus to these toxic environmental contaminants, which have the ability to induce poor perinatal outcomes, including low birth weight (<2,500g) and preterm