Estimating the public health benefits with reducing current levels of NO2 and SO2 in Mexico

Abstract

Introduction Urban air quality represents a major public health burden and is a long-standing concern to Mexican citizens. HIA aims to assess the potential impacts of a proposal and make recommendations to improve the potential health outcomes and minimize inequalities. Several health impact assessments (HIA) have already reported the major public health burden of particulate matter and ozone around the world and few studies have focused on other pollutants such as NO2 and SO2. Current Mexican air quality standards for NO2 and SO2 are obsolete and still above the World Health Organization Air Quality Guidelines (WHO-AQG) that aims to protect public health. The aim of this study is provide a national estimate of the potential health and monetary benefits of reducing air quality standards (NO2 and SO2) in Mexico. Methods The health benefits of changes in air pollution are expressed as avoidable mortality using 2013 data. We considered two scenarios of reduction of current annual levels for both pollutants: a decrease of the air pollutant levels by a short term fixed amount and adjust according to the WHO-AQG. Total mortality was estimated for NO2 and respiratory diseases for SO2. Monetary benefits were estimated using a Value of a Statistical Life approach. Results Considering a reduction of current levels of NO2 and SO2 as WHO-AQG about 2,059 (1,497-2,629) deaths per year could have been avoided and 4,459 (1,245-6,420) could have been avoided for SO2. Avoidable deaths mean approximately 42 and 92 billions of USD, respectively. Conclusions Our study provided useful information to policy makers and confirms that reducing urban air pollution would result in significant health and monetary gains to Mexico. Our results are particularly relevant now when the current Mexican legislation is being revised for an update in 2016 and 2017. Reanalysis of costs with more accurate methods are still to be performed.