Air quality in Lima

How bad are the air pollution levels in Lima?

Lima is the capital city of Peru, as well as being the largest in the country and third largest out of all cities in the Americas, coming in behind Sao Paulo and Mexico City. As well having a considerable size to it, Lima is also the economic, political and cultural heart of the country.

In terms of its levels of pollution, Lima was observed to have had a PM2.5 reading of 23.7 μg/m³ in 2019, as its yearly average. This reading would put it into the ‘moderate’ rated pollution bracket, which requires any reading between 12.1 to 35.4 μg/m³ to be classed as such. This puts it in the mid-range of the moderate bracket, with many months of its year staying fairly consistent within this rating and not straying out of it at all for the entirety of 2019, a quite unusual feat amongst cities worldwide, which usually see drastic changes in their pollution ratings, fluctuating between months.

This 2019 reading of 23.7 μg/m³ placed it into the 682^nd place out of all polluted cities worldwide, as well as being the number one most polluted city in Peru, out of only 3 registered, with the other two being Trujillo and Chupaca. It is evident that whilst Lima does not see any drastic spikes in its pollution levels throughout the year, its ambient pollution ratings are high enough that it could cause problems for many of its inhabitants, particularly those with a sensitivity towards chemicals or pollutants, or those with preexisting respiratory conditions.

When does Lima have its worst levels of air quality?

Observing the data taken once again over the year of 2019, the months that came in with the worst levels of pollution were generally in the mid to end portion of the year, with the earlier months showing some of the cleaner readings. Declines in air quality levels become apparent in April, which came in with a reading of 19.4 μg/m³, followed by a sudden spike in PM2.5 up to 29.1 μg/m³ in May, and then a further rise up to 31.3 μg/m³ in June. The readings from here out stayed fairly consistent in these numbers, with an absolute high of 34.2 μg/m³ being recorded in September, making it the most polluted month out of the year.

After its peak in September, pollution levels began to decline again gradually, with October dropping down to 29.5 μg/m³, 22 μg/m³ in November and a further drop to 19.8 μg/m³ in December.

The cleanest months of the year were the first three, with January, February and March coming in with readings of 13.9 μg/m³, 12.1 μg/m³ and 15.4 μg/m³ respectively, making February the cleanest month out of the year in terms of air quality, and only 0.1 unit away from being moved down into the ‘good’ ratings category, which requires a fine margin of 10 to 12 μg/m³ to be classed as such.

What are the main causes of air pollution in Lima?

With close to 9 million inhabitants, Lima sees much of its pollution arising from sources such as vehicular emissions, with many people commuting back and forth to work each day, often in vehicles that are considered old and outdated by international standards, running on unclean fuel sources and putting out large volumes of fumes and haze, all of which add to the constant levels of air pollution seen year-round.

Other sources of pollution include instances of industrial emissions, with factories also being responsible for putting out large amounts of pollution and running on unclean fossil fuel sources such as coal.

These two would be the most prominent causes of pollution in Lima, with other ones also contributing to the yearly readings, such as the open burning of refuse and dangerous materials such as rubber tires or plastic waste, as well as organic garbage.

The open burning of rubbish piles can present serious health risks due to the large number of items found amongst the refuse being unfit for burning, and without disposal in a proper manner can lead to a large host of health and environmental issues amongst those that are exposed to their fumes. Other sources would include finely ground dust from road repairs and construction sites, adding to the levels of PM2.5 and PM10 in the air.

Is the air quality in Lima showing signs of improvement?

Looking at the data collected over the last few years, it is evident that despite still having many pollutive issues, PM2.5 readings have actually improved somewhat between 2017 to 2019. In 2017 the yearly average was recorded as 27.7 μg/m³, putting it into the higher end of the moderate bracket.

In 2018 the reading actually got worse and came in at 28 μg/m³, a very slight difference but still a negative one regardless. Back to more recent years, 2019 made an improvement of 4.3 units and presented with 23.7 μg/m³.

Whilst this is a positive step in the right direction, Lima still has a long way to go if it is to achieve the World Health Organization’s (WHO) target goal for clean air of 0 to 10 μg/m³.

What are some health issues associated with breathing polluted air in Lima?

With sources of pollution such as vehicular fumes, construction and road dust as well as open burning sources, when caught in areas of elevated pollution for extended periods of time, the health effects not only become more prominent but become more numerous in possibility.

Some of these would include heightened instances of lung cancer, as well as irritation to the skin, throat, eyes and nose, causing a decrease in quality of life for Lima’s inhabitants as well as an increased mortality rate. Fumes from synthetic materials such as plastic can cause damage to the nervous system, with irreversible effects such as chronic fatigue, headaches, cognitive and physiological changes as well as a whole host of issues for sensitive groups such as young children or pregnant mothers.

Pregnant mothers exposed to excessive pollution can have higher rates of miscarriage, as well as babies being born prematurely or with a low birth weight, sometimes having the aforementioned cognitive and physical defects present. These are but a few of the health problems associated with breathing elevated levels of pollution, with other such unwanted ailments such as damage to the liver and kidneys, reproductive system as well as heart all being possible.