Mexico's Air Pollution: A Critical Issue

Air pollution is a significant issue in Mexico, with the country ranked 46th in the world for its high concentration of airborne particles (PM 2.5). Mexico City, in particular, has long been known for its poor air quality, previously earning the title of the most polluted city in the world by the United Nations in 1992. The city's rapid population growth, industrialization, and proliferation of vehicles have contributed to this problem. While Mexico has implemented policies and shown improvements in air quality, air pollution remains a critical issue with health, environmental, and economic impacts. The country continues to face the challenge of reducing emissions and improving air quality, especially in urban areas.

Population growth and industrialisation

Mexico City's population has been growing rapidly since the 20th century, with the population increasing from 3 million in 1950 to 20 million in 2015. This population boom was largely due to industrialization, which attracted thousands of migrants from around the world seeking better opportunities. The growth in population, combined with industrialization, led to a significant increase in human activities, including the use of vehicles, power plants, and industrial processes, all of which contributed to air pollution.

The proliferation of vehicles in Mexico City is a significant factor in the city's air pollution issues. As the population increased, so did the number of vehicles on the road. In 1980, there were 124 cars and light-duty trucks per 1000 residents in Mexico City, and by 2010, this number had increased to 267. The increase in vehicles led to greater emissions of pollutants, such as nitrogen oxides, carbon monoxide, and particulate matter, which contributed to the poor air quality in the city.

Industrialization has also played a significant role in Mexico City's air pollution problems. The industrial growth that occurred as a result of the population boom led to the emission of over 11,000 tons of waste material into the atmosphere every day. In addition, non-regulated and highly polluting factories, power plants, and oil refineries operated throughout the city, emitting large amounts of pollutants into the air. The topography of Mexico City further exacerbated the issue, as the city is located in a basin where air pollutants tend to be trapped, making it difficult for them to disperse.

The combination of population growth and industrialization has resulted in a significant increase in human activities, including the use of vehicles and industrial processes, which have led to high levels of air pollution in Mexico City. The city's high altitude of 7382 feet above sea level also contributes to the issue, as it causes oxygen levels to be 25% lower, and carbon-based fuels do not combust completely, leading to increased emissions of pollutants.

To combat the air pollution issues caused by population growth and industrialization, the Mexican government has implemented various policies and initiatives. The Hoy No Circula program, introduced in 1989, requires vehicles to go through emissions testing every six months and prohibits driving on certain days of the week based on their emission performance. The government has also mandated the removal of lead from gasoline, the implementation of catalytic converters, and the reduction of sulphur content in diesel fuel. In addition, polluting factories have been closed or moved, and there has been an expansion of public transportation and green areas, as well as improved bicycle accessibility. These measures have helped to significantly improve the air quality in Mexico City, with the city dropping to the 917th most polluted city in the world in 2021, according to IQAir.

Vehicle emissions

The majority of these vehicles run on fossil fuels, which produce emissions of PM, NOx, and volatile organic compounds (VOCs). In Mexico City, there are approximately 8 million vehicles, and these generate more than 7,000 tons of pollutants every day. The city's high altitude and geographic basin also trap pollutants, exacerbating the issue. The basin topography means that air pollutants are often trapped, and the city's high altitude (7382 ft above sea level) means that oxygen levels are 25% lower, which affects the combustion of carbon-based fuels.

In response to the problem of vehicle emissions, the Mexican government has implemented various policies and regulations. In Mexico City and the state of Mexico, all vehicles are required to undergo emissions testing every six months and are then issued with a verification based on their performance. The Hoy No Circula policy, first introduced in 1989, forbids driving on one or two days a week, depending on the vehicle's emissions level. The Mexican Atmospheric Environmental Contingency Plan (AECP), reactivated in 2016, also included further restrictions on vehicle use.

To improve air quality, Mexico has also implemented clean energy initiatives, including removing lead from gasoline, reducing sulphur content in diesel fuel, closing an oil refinery, and reformulating liquified petroleum gas for cooking and heating. Mexico City has also invested in electric buses and electric taxis, and is using green inspectors and remote sensors to identify high-emitting vehicles. The city has also joined the BreatheLife programme, which includes initiatives to improve energy efficiency and promote public transport.

Poor regulatory framework

Mexico has had air quality legislation in place since the 1970s, with the current framework focusing on seven criteria pollutants: carbon monoxide (CO), ozone (O3), nitrogen dioxide (NO2), particulate matter (PM2.5 and PM10), sulfur dioxide (SO2), and lead (Pb). However, Mexico's air pollution problem persists, and experts point to a lax and outdated regulatory framework that fails to prioritize human health and protect Mexicans' right to a healthy environment and clean air.

The Mexican government has been criticized for not generating valid and timely information on air quality. The National Report on Air Quality conducted in 2017 revealed alarming results, with only 8 out of 177 stations complying with ozone monitoring standards. This lack of accurate and up-to-date data hinders effective decision-making and policy formulation.

The regulatory framework has struggled to keep pace with the rapidly changing industrial and urban landscape in Mexico. Since the 1950s, Mexico has experienced a significant population boom, with the population soaring from three million in 1950 to over 120 million today. This has been accompanied by a proliferation of vehicles, with more than 3.5 million registered vehicles, 30% of which are over 20 years old. The combination of population growth and increasing vehicle emissions has severely impacted air quality.

Moreover, Mexico's environmental policies often lack the necessary financial and political support from the federal government, hindering their effectiveness. While local governments have taken the initiative to address air pollution, the federal government's role in environmental policy is crucial. The complex interplay between federal and local jurisdictions has created challenges in implementing comprehensive solutions to air pollution.

To address these issues, Mexico needs to strengthen its regulatory framework by updating standards, prioritizing human health, and enforcing compliance among the most polluting sectors. Additionally, improving data collection and monitoring systems will provide a more accurate understanding of air quality status. A concerted effort by all levels of government, including intergovernmental cooperation, is essential to tackle air pollution effectively and ensure the right to clean air for all Mexicans.

Health and economic impacts

Air pollution in Mexico has had a significant impact on the health of its citizens. The presence of harmful substances in the atmosphere, such as ozone, particulate matter (PM10 and PM2.5), carbon monoxide, nitrogen dioxide, and sulfur dioxide, poses a severe risk to public health. The World Health Organization (WHO) has set a limit for average outdoor air pollution of 10 micrograms per cubic metre of PM2.5 (particulate matter less than 2.5 micrometres in diameter). These fine particles can penetrate deep into the lungs and cause various health issues. Mexico City, in particular, has been notorious for its poor air quality, with annual mean levels of PM2.5 exceeding the WHO-recommended limit. The pollution in the city has been linked to respiratory illnesses, with accounts mentioning birds falling out of the sky due to the toxic air. The health consequences of air pollution in Mexico City have resulted in substantial healthcare costs and a decrease in economic output. Workers experience loss of productivity and earnings due to the high levels of pollution, with an average loss of 7.5% of working hours on days with high PM2.5 concentrations, resulting in economic losses of over USD 8 billion in 2020.

Indoor air pollution is also a significant health concern in Mexico. The use of solid fuels such as wood, crop residues, and dried animal dung for cooking and heating is common in Mexican households, especially in rural areas. These fuels emit substantial amounts of toxic pollutants, and when used in poorly ventilated spaces, can severely impact the health of household members, particularly women and children who spend more time indoors. Pollution levels in these households can be much higher than in urban areas, and the exposure to toxic pollutants can be several times higher than the WHO guidelines.

The economic impacts of air pollution in Mexico are closely tied to the health consequences. The healthcare costs associated with treating diseases related to air pollution place a significant financial burden on the country's healthcare system. Additionally, the loss of productivity and earnings among workers affected by air pollution contributes to the economic losses. The Mexican government has recognised the importance of reducing air pollution to promote economic development in the region. The success of initiatives such as the "Hoy No Circula" program and the expansion of public transportation show that the country is taking steps to address the issue.

While Mexico has made notable progress in reducing air pollution, especially in Mexico City, it still faces challenges in implementing effective policies due to the lack of financial and political support from the federal government. The current environmental policies are often left to local governments to handle, which can hinder the country's ability to tackle the issue on a national scale. Additionally, the regulatory framework determining the maximum limits for pollutants in the air is considered lax and outdated, with the State falling short in providing timely and valid information on air quality.

To address these issues, Mexico needs to strengthen its regulatory frameworks, increase public awareness, and focus on implementing more stringent emissions standards. The promotion of electric vehicles, public transportation, renewable energy, and clean stoves can significantly reduce pollution levels. Additionally, modifying mobility systems to prioritise electric public transport, active transport such as cycling and walking, and reducing emissions from transport within the city centre are crucial steps towards improving air quality.

Environmental policies

Mexico has implemented several policies to combat air pollution, which has been a major issue in the country, particularly in Mexico City, for decades. In 1992, the United Nations declared Mexico City the "most polluted city on the planet", and it retained this title for several years. The city's high altitude of 7382 feet above sea level, rapid industrialisation, population growth, and proliferation of vehicles were major contributors to its poor air quality.

The Mexican government has since taken several initiatives to improve air quality, with notable success. By 2021, Mexico City's ranking dropped to 917th most polluted city in the world. Some of the government's policies include:

• Requiring gasoline reformulation to reduce emissions.
• Closing down or relocating polluting factories.
• Prohibiting drivers from using their cars one day a week ("Hoy No Circula" policy).
• Expanding public transportation, including investing in electric buses.
• Encouraging the use of bicycles and increasing green areas.
• Strengthening inspection and surveillance systems to prevent illegal changes in land use, which often lead to deforestation.
• Setting a goal of achieving zero deforestation by 2030.
• Promoting the use of electric vehicles and renewable energy sources.

While these policies have led to significant improvements, air pollution remains a critical issue in Mexico, particularly in urban areas. The country continues to face high pollution levels, and further efforts are needed to address emissions and curb future air quality concerns. There is also a need for stronger financial and political backing from the federal government to support local government initiatives.

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