The official State of the Environment Report 2011, released this week, found that the limits set for ambient fine particulate matter - PM 2.5, which refers to particles measuring less than 2.5 micrometres in diameter - were exceeded in 30 cities in this long, narrow South American country.
PM 2.5 has a profound effect on public health. Studies have linked fine particle pollution to heart disease, strokes, respiratory problems, and premature death.
Experts in Chile say fine particulate matter from copper smelters, thermoelectric plants, and woodstoves used to heat homes affects 10 of Chile’s 17 million people, and is dangerous because it penetrates the deepest part of the lungs, such as the alveoli or bronchioles.
Sepúlveda told IPS that during the southern hemisphere winter – which officially begins on Jun. 21 – influenza epidemics, cold temperatures and air pollution combine to create conditions in which respiratory ailments thrive.
"All of these things come together, and the health system collapses," she said. In response to this situation, staff at the main public health emergency care hospital in Santiago, the Hospital de Urgencia de la Asistencia Pública, held a strike on Tuesday.
The authorities must urgently address the situation with anti-smog plans that are truly effective, Sepúlveda said.
She suggested, for example, including biomedical indicators in the decision-making process that leads to the declaration of environmental emergencies.
During states of smog emergency and pre-emergency, vehicles are ordered off the streets, factories are temporarily shut down, schools suspend physical education, and families are recommended to keep the elderly and small children at home.
The report published by the Environment Ministry on Wednesday Jun. 6 indicates that the southern cities of Rancagua, Curicó and Coyhaique have the worst air quality in the entire country.
In the southern part of the country, where winter temperatures frequently dip below freezing, the most common form of household heating is woodstoves, which have a detrimental effect on both indoor and outdoor air quality.
In the Santiago Metropolitan Region, which is situated in a valley between Chile’s coastal mountain range and the Andes, the most heavily affected district is Cerro Navia, a lower-income area on the west side of the city that also suffers the effects of overburdened public and private health centres.
Since 1992, the authorities have issued 12 decrees to combat the problem, aimed at curbing emissions from fixed sources such as factories, thermopower plants and homes, and from public and private transport.
There are also nine anti-smog plans currently in operation, from the northern region of Antofagasta to the Araucanía region in the south.
But there are no methods for monitoring and enforcing the PM 2.5 limit for emissions.
The environmental assessment presented by Environment Minister María Ignacia Benítez also took into account soil contamination, garbage, noise pollution, access to clean water and sanitation, availability of green areas, and the country’s environmental heritage.
Benítez stressed the effort her ministry was making to bring transparency to the problem of pollution, and underlined that it was not new.
It would be important to have "stricter norms," she said, "to be able to develop strategies that make it possible to reduce the levels of fine particulate matter.
"In that way, saturated zones can be declared, air clean-up plans can be carried out, and restrictions can be set," she added.
For his part, Patricio Pérez, the director of the Meteorological and Environmental Centre at the University of Santiago, told IPS that the report is "quite illustrative of what is occurring in the country with respect to the environment, especially in terms of fine particulate matter, which is what is measured in different cities.
"This information is alarming because we always only talk about the situation in Santiago, where levels are already quite high and worrisome in terms of international health standards, and now it is clear that the capital is not the most heavily affected city," he said.
Pérez, one of the creators of the Modelo Neuronal, one of the three air quality modelling systems used to predict air pollution levels in the capital, said this kind of instrument "only enables us to slightly anticipate what is going to happen, but with the tools currently available, it is impossible to prevent high pollution events."
In his view, the biggest hurdle standing in the way of resolving the decades-old problem is raising awareness of the dangers people are facing.
"The smell of wood smoke in the air in cities in the south has been around for a long, long time, but only recently has it begun to be understood that the aroma is not romantic, but a sign of something that is harmful to health," he said.
Nor has the information from the health authorities reached the public, he said. "Measurements of pollution levels began not too long ago; in fact we are just now completing the system of measuring fine particulate matter in Santiago, so what can we expect in other cities?" he added.
Pérez said different measures are needed to address the specific situation in each region. But he added that "it is not realistic" to think that a definitive solution will be found any time soon.