Air quality in Sharjah

What are the current levels of air pollution in Sharjah?

Sharjah is a city located in the Dubai-Sharjah-Ajman metropolitan area of the United Arab Emirates, or UAE as it is more commonly known in short form. It is the third most populous city in the country, coming in behind Dubai and Abu Dhabi, being home to some 12.7 million inhabitants, as of 2017. Much like the rest of the country, as well as many neighboring ones, Sharjah is subject to some high levels of air pollution, with certain months bringing with them even higher levels of smoke, haze and fine particles permeating the atmosphere.

For the units of measurement that will be used when addressing the pollution issues in Sharjah, both PM2.5 and US AQI will be referred to. PM2.5 is often used to take yearly averages, and is considered as one of the most dangerous forms of air pollution present, being 2.5 micrometers in diameter, and able to go down to sizes many microns smaller. This extremely small size, coupled with the large amount of hazardous materials it can be comprised of, is why it is considered to be such a hazard. It is able to penetrate deep into the tissue of the lungs upon inhalation, and from there enter into the bloodstream via the alveoli, or small air sacs in the lungs.

US AQI itself is a number aggregated from the volume of the several main pollutants present in the atmosphere, with PM2.5 being counted among them (as well as being a prominent measure of air pollution in its own right). The other forms of air pollution present in Sharjah that go into making up this US AQI figure would be ones such as nitrogen dioxide (NO₂), sulfur dioxide (SO₂) and ozone (O₃), along with the larger form of particulate matter, PM10.

In mid-2021, in the early days of June, Sharjah presented with a US AQI reading of 95, placing it into the higher end of the 'moderate' pollution ratings bracket. This is color coded as yellow, for ease of reference when observing the air quality maps and graphs in use throughout the IQAir website. In order for this 'moderate' rating to be attained, a reading of anywhere between 51 and 100 must be met. Whilst the US Environmental Protection Agency (EPA) deems any reading between 0 to 150 as being within the acceptable range, it must be noted that as the US AQI number rises and reaches the higher end of this spectrum, negative effects may start to present themselves, particularly amongst vulnerable individuals.

Other readings of US AQI present in Sharjah include ones such as 103 and 110, both of which would be placed into the 'unhealthy for sensitive groups' bracket, one step up from the 'moderate' rating. This is color coded as orange, and requires a US AQI reading of 101 to 150 to be classified as such. Readings above 150 start to move into the ‘unhealthy’ ratings territory, where all members of the population will start to experience adverse respiratory and cardiac symptoms. Of note is that the above mentioned reading of 97 may present itself with some adverse effects amongst vulnerable groups such as pregnant women, the elderly, or the immunocompromised, but as a whole the general public will remain largely unaffected. Pollution levels can still fluctuate, causing decent air quality readings to spike up rapidly, and as such, staying up to date on the level of air pollution present becomes of greater importance.

What causes higher air pollution levels in Sharjah?

In 2020, Sharjah presented with a yearly PM2.5 average of 26.8 μg/m³, placing it into the 'moderate' rating bracket once again, with the difference that a PM2.5 rating equivalent is measured in micrograms per cubic meter (μg/m³), and requires a reading of 12.1 to 35.4 μg/m³ to be classified as such. This reading placed Sharjah in 498^th place out of all cities ranked worldwide for 2020, as well as in 2^nd place out of all cities currently ranked in the United Arab Emirates, coming in just behind Dubai.

The reasons as to why Sharjah has such high pollution levels are usually ones related to a large increase in overall population size, along with increased vehicle ownership, construction and infrastructural growth, along with other industrial based factors. The overuse of vehicles in Sharjah has led to large amounts of exhaust fumes permeating the air, containing many different dangerous chemical compounds and fine particles. Heavy freight vehicles would also see a large amount of use, often running on diesel fuel and putting out far more pollution per vehicle than a smaller counterpart would.

The construction of roads and buildings, along with road repairs and other similar sites would all release their own heavy forms of pollution into the air, along with the heavy machinery used at such sites also running on fossil fuels such as diesel. These are a few of the polluting factors present in Sharjah.

What are some of the main types of pollution present in Sharjah?

Besides the aforementioned pollutants that go into the US AQI collective, Sharjah would have a number of other ones present in its atmosphere, particularly concentrated in certain areas (such as ones that see a high volume of traffic, along with industrial areas). These would be pollutants such as volatile organic compounds (VOCs) and black carbon, both of which are released from the burning of both fossil fuels and organic matter.

Construction sites and factories can leak toxic metals such as mercury and lead into the surrounding environment, along with dioxins, furans and polycyclic aromatic hydrocarbons. Some examples of the aforementioned VOCs include chemicals such as toluene, xylene, methylene chloride and styrene.

When is Sharjah at its most polluted?

Observing the air quality levels present in 2020, it can be seen that Sharjah had several months that came in with higher readings of PM2.5 than the rest of the year. These months were June through to September, all of which came in with readings of 39.4 μg/m³, 31.8 μg/m³, 35.8 μg/m³ and 36.9 μg/m³. This placed three of the months into the 'unhealthy for sensitive groups' bracket (35.5 μg/m³ and beyond), making this period of the year the one with the highest levels of air pollution, which was also mirrored identically in Dubai during the same time frame.

Has Sharjah improved its air quality levels?

Looking at the PM2.5 readings from years past, it can be seen that Sharjah has indeed improved upon its yearly averages by a significant amount. In 2018, Sharjah came in with a yearly average of 37.6 μg/m³, followed by a reading of 34.6 μg/m³ in 2019.

The reading of 26.8 μg/m³ in 2020 shows a marked improvement, and if such a trend can be continued (and is not just owed to the mass reductions in worldwide pollution levels due to the covid-19 outbreak), then the city may see some significant increases in its level of air quality in the years to come.