A new pollution survey conducted by the World Health Organization has revealed some discouraging truths about Lima.
According to EFE, Lima presented the worst air pollution indicators of any city in Latin America.
The survey, EFE writes, is not a worldwide ranking of the most or least polluted cities. The data used by WHO in compiling the study was given voluntarily by participating countries, which means that the data is difficult to compare objectively due to variations in measuring techniques, year in which the data was collected, and other factors.
However, the Lima data showed that the city’s air contains high levels of particulate matter known as PM 2.5, tiny particles that are able to penetrate human lung tissue and cause damage. The study also looked at levels of PM 10 in some cities, another kind of particulate matter that is larger and therefore less dangerous to humans.
Lima’s PM 2.5 levels varied throughout the city. In Lima Norte, data showed levels as high as 58 micrograms per cubic meter of PM 2.5; in Lima Este 36 micrograms; and in Lima Sur 29 micrograms. According to the WHO, EFE reports, a reasonable level for PM 2.5 is 10 micrograms per cubic meter.
The “cleanest” city in Latin America was Salvador de Bahia in Brazil, which had an annual average of 9 micrograms of PM 2.5 per cubic meter.
“We look at the annual average, because that’s what gives us a real indication of what kind of long-term danger people are being exposed to. Every place has peaks of pollutions, but this can be tied to temporary phenomenon and doesn’t have [the same kind of] consequences,” said Maria Neira, WHO director of public health and the environment.
WHO’s website on air pollution says that “Only 12% of the people living in cities reporting on air quality reside in cities where this complies with WHO air quality guideline levels. About half of the urban population being monitored is exposed to air pollution that is at least 2.5 times higher than the levels WHO recommends – putting those people at additional risk of serious, long-term health problems.”
The study found that air pollution in cities is only becoming more severe. “The most important thing we should highlight is the fact that the situation is getting worse almost everywhere, especially in developing countries,” said Neira.
According to the WHO website, rising air pollution is caused by a number of factors, including “reliance on fossil fuels such as coal fired power plants, dependence on private transport motor vehicles, inefficient use of energy in buildings, and the use of biomass for cooking and heating.”