圣保罗的空气质量

What is air quality like in Sao Paulo?

Sao Paulo is a city in brazil, located within the state of the same name and being the capital city of said state. It is the most populous city in the whole country, as well as the continent, being the wealthiest region in Brazil and thus its economic and cultural heart.

In regards to the its air quality, Sao Paulo can be examined for its pollution levels over the year of 2019. As a yearly average, its PM2.5 reading was 15.3 μg/m³, placing it within the lower end of the ‘moderate’ pollution bracket, which requires a reading of anywhere between 12.1 to 35.4 μg/m³ to be classified as such. This reading placed it into 9^th place out of all cities registered in Brazil, coming in behind other cities such as Santos and Rio Branco, both of which had higher readings of 15.4 μg/m³ and 16 μg/m³, with Campinas city taking the first-place position in 2019 with a PM2.5 reading of 20 μg/m³.

Sao Paulo’s PM2.5 reading of 15.3 μg/m³ placed it into the 1210^th place out of all the most polluted cities ranked worldwide. This is a both a fairly respectable pollution reading as well as placing, with pollution levels that are not excessive in nature and with several months out of its year coming in with ‘good’ ratings of pollution.

Despite this, it should be noted that any PM2.5 reading above the World Health Organizations (WHO) target goal of 0 to 10 μg/m³ may have detrimental effects on the health of those exposed. As such, whilst the pollution levels are moderate in nature, they may present some adverse effects for certain portions of the population, such as the young, elderly and those with preexisting illnesses or respiratory conditions.

What are the main causes of air pollution in Sao Paulo?

The main causes of air pollution and contamination seem to emanate from several sources, with some being more prominent than others. The one that appears to have the most prominence, as is seen in many large cities around the world, is that of vehicular fumes and emissions.

This is a problem that is only going to increase as more people migrate into urban areas such as Sao Paulo, not only causing the already high population to rise but also the prevalence of vehicle usage to go up massively.

Whilst vehicles and high levels of traffic are responsible for the elevated pollution levels, not all vehicles release pollution equally, with older and outdated models that run on diesel fuels being worse offenders than their newer counterparts, as well as ‘heavy duty vehicles’ such as trucks, lorries and buses being responsible for elevated emissions.

Other sources of pollution would include particulate matter released from construction sites, the combustion of materials such as wood or plants in any form of open burning site (as is common place in many areas of lower income, due to the use of burning materials for cooking or similar activities), as well as emissions from the many factories found within the city’s limits.

When is the air quality at its worst in Sao Paulo?

Observing the data taken over the last few years, the months that stand out with the worst levels of pollution in Sao Paulo were in the middle portion of the year. The month with the highest levels of PM2.5 was July, with a reading of 20.8 μg/m³. Other times of poorer air quality took place during the surrounding months, with June and September also coming in with elevated readings of 19.8 μg/m³ and 17.8 μg/m³ respectively.

PM2.5 refers to fine particulate matter that is 2.5 micrometers or less in diameter, making it roughly 3% the width of a human hair. Due to its incredibly small size, it has a large number of negative health effects when inhaled, and for this reason it finds great prominence in being used to calculate overall pollution levels in the air, being a major component in determining the US AQI.

When is Sao Paulo air at its cleanest?

The months that came in with the cleanest readings of PM2.5 numbered four in total throughout 2019, with these four months being the only ones that fell beneath the moderate ratings bracket into the good ratings one. They were February, March, November and December.

They all came in with very similar readings, with February and March showing PM2.5 levels of 11.2 μg/m³ and 11.3 μg/m³, only 0.1 unit apart, and November and December showing 11.4 μg/m³ and 11.1 μg/m³.

Although these numbers are still slightly above the WHO’s target goal for clean air, they would be the months of the year where the air would be at its most breathable, and negative health issues that arise from breathing polluted air would be minimal.

What are some health risks from pollution in Sao Paulo?

With a vast number of citizens all commuting across the city, caught in the infamous levels of rush hour traffic, subsequently many people would be exposed to elevated and dangerous levels of pollution, with compounds and materials such as nitrogen dioxide (NO­₂) and sulfur dioxide (SO₂) being highly present in the air from rush hour fumes, as well as fine particulate matter such as black carbon.

Black carbon in itself has carcinogenic properties, and due to its small size, can penetrate deep into the lung tissues and cause problems to arise. These problems would be scarring or aging of the lungs themselves, reducing their full function and capacity, which in turn would lead to a rise in respiratory ailments such as pneumonia, bronchitis, emphysema as well as aggravated forms of asthma, with nitrogen dioxide being a prominent chemical compound known to trigger off asthma attacks.

Particulate matter, including black carbon and others such as silica dust or toxic metals such as mercury or lead can be released from construction sites and make their way into people’s bodies via the lungs. If these particles are of small enough size (particularly PM2.5), they can penetrate into the blood stream via the alveoli sacs and make their way into the circulatory system, which can cause damage to the blood vessels, instances of ischemic heart disease to occur (whereby the heart fails to receive enough oxygen to its tissues), as well as increased risks of cardiac events such as heart attacks or arrythmias.

These are but a small number of health issues associated with exposure to pollution, therefore stressing the importance of not only countrywide measures in reducing air pollution, but also individual preventative measures such as the wearing of particle filtering masks, as well as avoiding outdoor activity during times of heightened pollution levels.