On January 1, 2025, the Comisión Ambiental de la Megalópolis (CAMe) activated the first phase of environmental contingency due to alarming air quality levels across Mexico City and the State of Mexico. This emergency measure was instigated following an increase of PM2.5 particles, which reached concentrations of 106.9 micrograms per cubic meter at the Nezahualcóyotl reporting station and 100.2 micrograms at Santiago Acahualtepec, particularly during the early hours of the day. Such levels are considered detrimental to public health, leading to immediate recommendations for the community.
The primary cause of this contamination spike has been linked to the widespread use of fireworks during festive celebrations and the burning of combustible materials. The raised pollution levels, significantly exacerbated by environmental factors, compelled authorities to implement air quality management protocols, culminating with the contingency declaration.
With this status now confirmed, the CAMe stated, "El día de hoy se registró un valor de 106.9 y 100.2 microgramos por metro cúbico de partículas PM2.5 en las estaciones Nezahualcóyotl y Santiago Acahualtepec." Consequently, double Hoy No Circula restrictions will be effective on January 2, prohibiting many vehicles from circulating within the metropolitan area as part of efforts to curtail pollutant levels.
The double Hoy No Circula program, which limits vehicle use based on their verification hologram, will target vehicles registered with verification 2, and those with verification 1 whose plate numbers end in 1, 2, 4, 6, 8, or 0. It also includes cars with no hologram, usually older models. Specific taxi operations will also face restrictions throughout the day.
This program, originally instituted to combat pollution, dictates traffic management during pollution peaks. Authorities recommend the continued use of public transport systems and advise the public to avoid engaging in outdoor activities throughout the day due to health risks associated with high particle concentrations. Recommendations explicitly include the avoidance of smoking, especially indoors, to minimize exposure to indoor pollutants, as reiterated by the CAMe when stating, "No fumar, en especial en espacios cerrados".
Experts stress the importance of following these precautions, as prolonged exposure to polluted air can exacerbate respiratory conditions and other health issues. For many residents of the metropolis, routinely following the Hoy No Circula program, established in 1989, is second nature and reflects broader efforts to promote sustainable transport options.
This recent activation serves as a reminder of the delicate balance between urban activity and environmental health. The CAMe has underscored the need for public vigilance and adherence to air quality advisories, particularly on days when the air quality index presents grave health risks.
Looking forward, the CAMe plans to release updates on the air quality status and the need for any additional restrictions beyond the initial phases. This vigilance is key to maintaining public health as weather conditions and pollution patterns evolve through the winter months.