Perched 7,300 feet above sea level in a valley wrapped round by mountains and volcanoes, Mexico City has long suffered from thick layers of smog produced by cars, factories, and wildfires. Among the worst hazards of that air pollution for its 21 million inhabitants is PM 2.5, inhalable fine particulate matter. People exposed to PM 2.5 can suffer from coughing, shortness of breath, bronchitis, respiratory infections and heart problems. When the city government closes schools or orders cars off the roads on days of particularly heavy smog, the danger from PM 2.5 is a principal concern.
Air pollution in Mexico City, and especially that from PM 2.5, has particularly dramatic effects on work. As we detail in a study of the problem, the roughly 3.5 million workers in the metropolitan area of Mexico City lose an average of 7.5% of their working hours on days of very high PM contamination. That amounts to $1.2 million in lost earnings on each of those days, which totals lost earnings of about $430 million in a given year.
Air Pollution and Inequality
But the dangers from PM 2.5, do not affect everyone equally, with significant differences between richer and poorer employees. As we discovered in our study, informal workers—those who generally work for small, unregistered companies without fixed salaries—tend to work more on days of high pollution than formal workers at established firms. In fact, they work on average 20% more than formal workers on those days of dangerous air quality. Moreover, they have less ability to make up for those lost hours on subsequent days. This inability to adjust more on days of high pollution and compensate more for their lost labor at other times has serious implications.
Our study also examined health outcomes and found that recent increases in hospital admissions for respiratory diseases have been driven by municipalities with large shares of informal workers. This means that informal workers suffer worse health and income effects of high air pollution than formal workers.
Social Programs to Mitigate the Effects of Air Pollution
Since 1992, when the United Nations named Mexico City the world’s most polluted city, successive local governments have imposed driving restrictions, created incentives for the purchase of cleaner vehicles, invested huge sums in public transport, built bike lanes, and curbed heavy industry in the city. While some of those measures have helped cleared the air and made the city more livable, other factors, like a doubling of the number of vehicles in the subsequent two decades have also caused air pollution to creep up. Today, pollution is a major health, labor and quality-of-life issue for all residents of the metropolis.
Our study shows that it is a particularly powerful issue for the poor. Given air pollution’s outsized impact in terms of income and health on them, the poor in Mexico City are especially concerned about air quality. In a 2019 survey of nearly 2000 households in lower-income neighborhoods of Mexico City, nearly 95% said that air pollution was a “problem” or a “big problem” in the city.
It is bad for the pocketbooks for the poor, their health, and because of the differences between the effects on rich and poor, for income inequality. With huge numbers of informal workers lacking any access to paid sick leave, the city has a real interest in mitigating those effects. One potential place to start is with social programs that economically support informal workers on heavy pollution days, helping them to avoid exposure and reducing their risk of respiratory and other pollution-related illnesses.