La air quality in Chile It has become one of the most relevant environmental and public health issues of recent decades. From critical episodes in Santiago to chronic problems in industrial areas and southern cities, millions of people breathe air daily with levels of pollution that can seriously affect their well-being. Far from being an abstract issue, we are talking about something that impacts the risk of suffering from respiratory and cardiovascular diseases, economic productivity, and even the quality of the environment where children grow up.
At the same time, Chile has one of the air quality monitoring networks The region's most developed countries have decontamination plans and advanced scientific tools to understand the origins of pollutants and their behavior in the atmosphere. National agencies, universities, and international organizations collaborate to measure, predict, and reduce pollution, but the challenge remains enormous, especially for the most vulnerable people and communities.
Air quality monitoring networks in Chile
In Chile, official information on air pollution is based on a network of monitoring stations Distributed across different regions of the country, these stations measure various regulated pollutants in near real-time, allowing authorities to issue environmental alerts and citizens to know the air quality they are breathing at any given moment.
The concentrations of these pollutants are compared with critical levels established in the regulationsThese criteria define when an environmental emergency occurs. It is important to note that, in many cases, the data displayed online has not yet been definitively validated, so it is considered preliminary and may be subject to adjustments once the station operators complete their quality control processes.
In the Santiago Metropolitan Region, the main network is the RED MACAMThis system integrates stations located in different municipalities to capture the spatial variability of pollution. Not all stations are always operational; for example, the El Bosque station is reportedly offline due to its relocation, meaning it is not generating data while this process is underway.
In other regions there are specific networks, such as the SIVICA NETWORK in Biobíowhich can also experience occasional interruptions. One example mentioned is the Nueva Libertad station, which has been undergoing maintenance on its transmitting antenna, affecting the transmission of online information. This situation serves as a reminder that atmospheric monitoring requires infrastructure, constant maintenance, and specialized technical resources.
In the coastal industrial zone of the Valparaíso Region, the following operates: Concón-Quintero-Puchuncaví NetworkThis network is key to monitoring one of the most sensitive areas in the country in terms of air pollution. Maintenance, calibration, and verification activities are regularly scheduled at stations such as Maitenes, Ventanas, Colmo, Concón, and Loncura. These activities may change according to technical needs, so schedule announcements are subject to change.
How data is presented and updated in SINCA
Much of the public information about the air quality in Chile It is visualized through SINCA (National Air Quality Information System). Its main map displays, by default, the stations that are connected online, that is, those that send data in near real-time. The user can also activate stations that are not connected online but that do have historical air quality data and meteorological variables.
All the data appearing in SINCA have one key characteristic: they are considered preliminary steps until formal validationThis means that, while these values are useful for understanding the current state of air quality and making quick decisions, they can change once the review and quality control process is completed. For this reason, both the Ministry of the Environment and other international projects warn that the published values may be modified without prior notice.
Due to maintenance work on the Ministry's technological infrastructure, the website and access to data You may experience intermittent issues. This type of maintenance is necessary to ensure the long-term stability of the system, but it means that, at certain times, the map or graphics may not respond normally.
It is important to note that the provision of this data is done with reasonable standards of care and rigorHowever, its absolute accuracy at every moment cannot be guaranteed. Initiatives such as the World Air Quality Index project, which compiles information from different networks, make it clear that neither they nor their teams can be legally held responsible for losses or damages resulting from the use of this data. It is, above all, a tool for public consultation and informed decision-making.
The records are usually updated every hour, although the frequency and quality of the data They depend on the type of contaminant and the proper functioning of the equipment. In some cases, if the percentage of available data does not reach a minimum, the corresponding average is not even calculated, as this would introduce a significant bias into the interpretation.
Main air pollutants and how they are calculated
In Chile, several are systematically monitored regulated pollutantsThese pollutants are associated with proven effects on human health and the environment. Among them are respirable particulate matter (PM10 and PM2,5), tropospheric ozone (O3), and sulfur dioxide (SO2)nitrogen dioxide (NO2) and carbon monoxide (CO). Each is measured and reported somewhat differently.
El respirable particulate matterBoth MP10 and MP2,5 are typically presented as a 24-hour moving average. These averages are based on continuous monitoring and are recalculated hourly, taking into account the previous 24 hours. For this average to be valid, at least 75% of the hourly data must be available (i.e., 18 or more values within the 24-hour window). If this threshold is not reached, the system does not provide the 24-hour average to avoid erroneous conclusions.
El ozone (O3)Ozone, a complex pollutant formed by photochemical reactions of other precursor gases, is reported as a 1-hour arithmetic average. This value is updated hourly and is also considered preliminary until verified by the station operator. Ozone has a strong relationship with solar radiation and... meteorological conditionsTherefore, their concentrations tend to vary greatly throughout the day.
As to sulfur dioxide (SO2)It is also reported using hourly arithmetic averages. Chilean regulations establish threshold values that help detect environmental emergency episodes associated with SO2 in the last hour of measurement. As with ozone, the data is updated every 60 minutes and may be modified after operational validation.
El nitrogen dioxide (NO2)Fuel emissions, primarily derived from combustion processes (vehicles, industries, boilers, among others), are continuously monitored and summarized as hourly averages. Hourly updates allow for a fairly rapid assessment of the impact of changes in traffic or industrial operations, although this is always subject to subsequent verification by the station operator.
Finally, the carbon monoxide (CO) It is presented differently: 8-hour moving averages are used, recalculated every hour. For this average to be valid, at least 75% of the data must be hourly (6 records within the 8-hour window). If the amount of data is less, the 8-hour moving average is simply not displayed, as it would be unrepresentative.
Health risks and regional context in the Americas
Air pollution is not just a technical issue: it is directly linked to people's healthIn the Americas, it is estimated that approximately 367.000 deaths occur each year related to both ambient (outdoor) and household (indoor) air pollution. These figures demonstrate the serious consequences that breathing polluted air can have, especially for those already in vulnerable situations.
The sources of the ambient air pollution These include vehicles that use fossil fuels, industries, power plants, and various productive activities that emit particles and gases into the atmosphere. In the home, everyday practices such as boiling water or cooking can increase exposure to pollutants, especially when using inefficient technologies or fuels like firewood in poorly ventilated spaces.
Among the health effects associated with a poor air quality These include an increase in respiratory infections, exacerbation of chronic diseases, and increased morbidity and mortality from ischemic heart disease, stroke, diabetes, and other cardiovascular and metabolic problems. These impacts are not evenly distributed: they disproportionately affect vulnerable groups such as children, the elderly, people with pre-existing conditions, and low-income communities.
From the international sphere, the Pan American Health Organization (PAHO) and the Inter-American Association of Sanitary and Environmental Engineering (AIDIS) have emphasized the need to strengthen monitoring systems and improve the response to pollution incidents. In virtual seminars and technical meetings, it has been emphasized that having robust data is the first step in designing effective public policies and protecting public health.
Furthermore, it has been recognized that air pollution has a economic impact This is significant, and in developing countries it can range from 2% to 4% of GDP. This includes costs associated with hospitalizations, absenteeism, decreased productivity, crop damage, and other indirect effects. Addressing air quality is not only an investment in health but also in sustainable economic development.
PAHO and AIDIS Initiatives: Inter-American Air Day and Tools
PAHO and AIDIS have established since 2002 the Inter-American Air Daywhich is celebrated every year on the second Friday of August. This commemoration seeks to highlight the importance of breathing clean air and to promote coordinated actions throughout the region. In one of its editions, the slogan was “Clean air, healthy life: it’s time to act,” underscoring the urgency of moving from diagnosis to the implementation of concrete measures.
During this period, virtual seminars such as “Monitoring Air Pollution Episodes, Mitigation Measures, and Health Impacts” are organized, with the participation of specialists from numerous countries. These meetings highlight the challenges for improve monitoring systemsTo facilitate coordinated responses to pollution incidents and to promote effective public policies at all levels of government, from national to local, with special attention to people in vulnerable situations.
PAHO representatives have highlighted the current leadership of several Latin American countries on the agenda of climate, environment and healthAmong the milestones mentioned are Brazil's G20 presidency, which promoted discussions on investment in this area with an equity focus, the COP16 on Biodiversity held in Colombia, which led to a global program on biodiversity and health, and the Second World Conference on Air Pollution and Health, where countries committed to reducing deaths linked to poor air quality in the Americas by 50% by 2040.
In this context, PAHO is finalizing a specific roadmap to improve air quality in the Americas, developed in conjunction with the countries of the region. The objective is to provide concrete guidance for policies, investments, and actions in the short, medium, and long term, integrating the equity component and the rights-based approach, in line with the United Nations declaration that recognizes the right of all people to a healthy environment.
AIDIS, for its part, has strengthened its internal structure by creating specialized working subgroups on topics such as air quality monitoring and its impact on healthLow-cost sensors and satellite monitoring, regulatory development and odor monitoring, and mitigation of pollutant emissions. These areas allow us to address air pollution from multiple angles, combining technology, regulation, public health, and citizen participation.
Forest fires, urban smog and their impact in Chile
One of the most worrying phenomena in recent years has been the increase in the large-scale forest firesespecially in the Amazon and other areas of South America. In 2024, exceptionally high emissions associated with adverse weather conditions were recorded between June and October, with an approximate 80% increase in the number of fires compared to the previous year and more than 60.000 hotspots detected during that period.
The smoke generated by these fires does not stay at the place of origin, but rather can travel thousands of kilometersaffecting air quality in very distant cities. Significant impacts have been reported in cities such as Asunción, Sao Paulo, Santa Cruz, La Paz, Corrientes and MontevideoThis demonstrates the transboundary nature of air pollution and the need for regional cooperation to address its effects.
In the case of Chile, in addition to forest fires, attention must be paid to the phenomenon of smog in big cities like Santiago. Specialists have warned that, at certain times of the year, the mixture of vehicular, industrial and residential heating emissions, added to unfavorable weather conditions, generates pollution episodes that literally "suffocate" the population, especially in the valleys where the air stagnates.
Environmental health experts have insisted that what pollutes the air does not remain suspended indefinitely: It ends up being deposited in soils and bodies of waterThis completes a cycle that affects entire ecosystems. In this way, poor air quality also influences water quality and soil health, generating cumulative impacts on biodiversity, agriculture, and the availability of natural resources.
To respond to these challenges, the importance of a air quality monitoring network A robust system is needed to allow for the comparison and validation of data and to facilitate coordinated decision-making. The lack of sufficient stations in certain areas hinders the assessment of the true impact of forest fires and other events, as well as the design of preventive and mitigation measures.
Tools for assessing health impacts: AirQ+ and training
With the aim of more precisely quantifying the effects of air pollution on healthThe Pan American Health Organization (PAHO) has promoted the use of the AirQ+ tool. This application allows for estimating the impact of exposure to different pollutants in terms of mortality and morbidity, based on monitoring data and epidemiological evidence.
The Spanish version of AirQ+ for the Americas regionThis facilitates its use by authorities, researchers, and healthcare professionals working in Spanish-speaking contexts. The tool helps to make the true cost of breathing polluted air more visible and serves as support for justifying stricter public policies regarding emissions regulations and urban planning.
To accompany this launch, PAHO has developed a training course on your Virtual CampusThis training provides step-by-step instruction on how to use AirQ+, interpret its results, and apply them to the design of public health and environmental interventions. This type of training is crucial for countries to maximize the benefits of the data generated by their monitoring networks.
Furthermore, a Regional Expert Group on AirQ+ for Latin America and the Caribbean. This group supports countries in using the tool, shares best practices, and helps harmonize methodologies so that results obtained in different places are comparable and a more robust regional view of the health impacts of air pollution can be built.
AirQ+ thus becomes part of a broader set of initiatives seeking to address environmental challenges. Within the shared agenda between PAHO and AIDIS, other Inter-American Days are also celebrated, such as the Inter-American Day of Cleanliness and Citizenship (September 20), Inter-American Water Day (October 4) and Inter-American Sanitation Day (November 19), all of them designed to strengthen awareness and joint action on environmental health.
Chilean research on air quality and technological solutions
In Chile, the scientific community plays a fundamental role in understanding the air pollution and its sourcesA prime example is the career of academic Ernesto Pino, from the School of Chemical Engineering at the Pontifical Catholic University of Valparaíso (PUCV), who has dedicated his career to studying the origin and behavior of pollutants present in the air using simulation tools.
According to Pino, the use of atmospheric simulation models It allows us to better understand the air we breathe, to know where pollutants come from and how they change over time. Thanks to these tools, pollution episodes can be predicted, preventative strategies can be designed, and control measures can be applied even in areas where there are no monitoring stations, thus reducing the exposure of communities and workers to harmful substances.
His work has addressed emblematic cases such as air quality in Quintero, Concón and PuchuncavíThe study found that industrial emissions have had a significant impact, and that residential wood burning has been identified as the main source of fine particulate matter (PM2,5) in urban areas such as Valparaíso and Viña del Mar. These results have paved the way for more detailed studies that aim to quantify the specific contribution of each pollution source.
In collaboration with Chemical Civil Engineering students from PUCV, Pino's team evaluated the feasibility of implementing a district heating system in ValdiviaThe results, recently published, indicate that this type of infrastructure could reduce the concentration of fine particulate matter in the city by 53%, representing enormous potential to improve the health of the population and the quality of life in an area where the use of firewood is widespread.
Currently, Ernesto Pino leads a Fondecyt Initiation project focused on the impact of marine emissions on air quality in coastal areas of Chile. This still relatively unexplored field analyzes the influence of natural compounds released by the ocean and their role in photochemical processes that modify the concentration of pollutants such as sulfur dioxide. A better understanding of these interactions helps to differentiate what comes from natural sources from what is generated by human activity.
The researcher emphasizes that the knowledge generated by this research is a crucial tool for the environmental public policiesAtmospheric modeling makes it possible to determine if a specific emission source is affecting a specific area, estimate the health impact of different measures, and guide regulatory decisions, urban planning, and the management of critical episodes in a more informed way.
Chile, environmental policies and the right to clean air
Since the 1990s, Chile has implemented a broad Decontamination Plan for the Metropolitan Region of Santiagowith a particular focus on controlling PM2,5 fine particles. According to specialists, since the implementation of this plan, the levels of these particles have been reduced by around 70%, which is associated with significant benefits in terms of public health, especially in the reduction of respiratory and cardiovascular diseases.
This Decontamination Plan has included various structural and management measuresThese measures include restrictions and improvements in transportation, requirements for certain industries, emissions controls from stationary sources, and regulations on the use of heating fuels. It also includes specific measures for managing high pollution episodes, supported by continuous monitoring and forecasting models that allow for anticipating worst-case scenarios.
This set of policies relies on assessment tools such as emissions inventories, health impact studies, and economic valuation analyses. These components allow for the quantification of the costs and benefits of each measure, enabling the prioritization of those that provide the greatest benefit. greater reduction of pollution for every dollar invested, something especially relevant in a context of limited resources.
A significant milestone was the creation in 2010 of Ministry of EnvironmentThis gave impetus to a National Air Strategy and a series of decontamination plans, emission standards, and the strengthening of the monitoring network. With this institutional framework, progress has been made in consolidating more comprehensive policies that connect air quality with other environmental challenges such as climate change, biodiversity, and waste management.
At the international level, it has been recalled that the United Nations General Assembly declared that Everyone has the right to a healthy environmentIn Chile, this vision is intertwined with the recognition of the constitutional right to live in an environment free from pollution, which introduces an additional legal and ethical dimension to air quality policies: it is not just about technical recommendations, but about guaranteeing a fundamental right.
Recent debates have also emphasized the need to greater awareness of government responsibility at its various levels (national, regional, and local) and in the importance of citizen participation. Without the commitment of communities, the private sector, and authorities, it is very difficult to sustain over time measures that involve changes in transportation, industry, or heating and energy consumption habits.
The situation in Chile and the region shows that, although notable progress has been made in monitoring, regulations and research, the challenge of breathing truly clean and healthy air It remains enormous. The combination of good monitoring networks, tools like AirQ+, robust decontamination plans, applied research, and active social participation points in the right direction to reduce health impacts, protect ecosystems, and ensure that the right to a healthy environment moves from being a declaration to becoming an everyday reality.
