جودة الهواء في Dushanbe

Does Dushanbe have highly polluted air?

Dushanbe is the capital city of Tajikistan, as well as being the largest in the country, home to some 863,400 people as of 2020. Located in the Gissar valley, it is a city that is also subject to some high levels of air pollution, coming in amongst some of the worlds most polluted cities, with air quality showing signs of being permeated by many different contaminating chemicals and particulate matter, which can cause a myriad of ill health effects amongst its population, particularly for vulnerable groups.

In late May of 2021, Dushanbe was seen with a US AQI reading of 50, placing it just within the ‘good’ air quality ratings bracket, as per the US AQI ratings chart. To be classified as having a good quality of air, the US AQI reading must come in between 0 to 50, showing the when this reading was taken, the city was just on the very cusp of being moved up to the next pollution ratings bracket (that of the ‘moderate’ rated one, which requires its own reading of anywhere between 51 to 100).

On the day that this reading was taken, the air quality would be of decent quality, a far cry from other times of the year when the pollution levels spike up significantly more, with such months being discussed further on in the article. US AQI itself is an aggregated unit that is calculated from the volume of various pollutants found in the air, typically the main ones that are present in cities throughout the world, regardless of location, due to their emanation from the main global sources of pollution (cars, fires, various other combustion sources and industrial areas).

Other readings of US AQI as taken over the months of May and April in 2021 came in with readings such as 62 and 92, both being classed as ‘moderate’ and color coded as yellow, which remains the same across all air quality maps and graphs throughout the IQAir website (with ‘good’ air quality ratings coming in with a green color code). The US Environmental Protection Agency (EPA) deems readings from 0 to 150 as being acceptable, and whilst many countries have their own measures of air quality, some of which vary in their classifications, the US AQI level is typically used as a golden standard due to its more stringent and rigorous ratings system.

Other readings taken during the aforementioned time period include highs of 116 and 127, both of which fell into the ‘unhealthy for sensitive groups’ bracket, which requires its own reading of 101 to 150. Whilst this is still within the EPA’s acceptable limit, when these upper levels are reached, symptoms may begin to appear amongst the general public and particularly amongst vulnerable individuals. As such, those who belong to at-risk groups should take care in order to reduce their exposure level. This can be done by following the air quality levels via the IQAir website or the AirVisual app, both of which come with hourly pollution updates and air quality forecasts.

What causes air pollution problems in Dushanbe?

Dushanbe and indeed much of Tajikistan suffers from the same pollutive issues, with these issues being separated into two main types of causes. One of them would be the industrial or anthropogenic side of air pollution, whilst the other would find its root cause in meteorological conditions such as strong winds during the summer months blowing many tons of super fine dust and sand particles into the city, coming from both local areas, as well as from surrounding countries such as Uzbekistan and Turkmenistan.

These ultrafine particles can cause many health issues when one is overexposed to them, with repeated inhalation over long periods of time leading to many health effects. These include forms of chronic obstructive pulmonary disease (COPD), with ultrafine particles causing irritation, aggravation or inflammation to the lining of the lungs and respiratory tract, along with scarring of the lung tissue. This can reduce full lung function as well as making individuals more susceptible to ailments such as pneumonia or bronchitis and other respiratory conditions.

Further causes include industrial or human based ones such as excessive use of cars and other motors, such as heavy freight vehicles like lorries and trucks. Many of these vehicles would be heavily aged and outdated, thus putting out far larger amounts of noxious oil vapors and dangerous particles when used, adding to the overall pollution level. Poor waste management and the practice of burning refuse or garbage in open and exposed piles would also be a contributing factor, along with poorly paved roads and construction sites adding to the particle pollution issue.

What are some or the main types of pollutants found in the air in Dushanbe?

Some of the main pollutants found in the air would be ones such as black carbon, which is the main component of soot and a potent carcinogen, along with volatile organic compounds (VOCs). Both can be formed from the incomplete combustion of fossil fuels and organic material, and thus can emanate from a number of sources. Some examples of VOCs include chemicals such as benzene, styrene, methylene chloride and formaldehyde.

Other main pollutants that go into the US AQI aggregate include the two types of particles, namely PM2.5 and PM10, along with ozone (O₃), nitrogen dioxide (NO₂) and sulfur dioxide (SO₂).

When does Dushanbe have the worst air pollution levels?

Using data collected from 2020, one can see that the most polluted months present in Dushanbe were August through to December, with January also having an elevated level of PM2.5 present in the air. their readings in order from August to December were 36.9 μg/m³, 36.8 μg/m³, 37.8 μg/m³, 39.9 μg/m³ and 41.5 μg/m³, along with January coming in at 42 μg/m³. This made January the most polluted month of the year, and all the aforementioned months coming in within the ‘unhealthy for sensitive groups’ bracket.

When is the air safest to breathe in Dushanbe?

The air in Dushanbe sees a relative respite from higher pollution readings from the months of February through to July. Whilst they were not perfect by any means, they still fell into the much better ‘moderate’ pollution ratings bracket, indicating lessened amounts of haze, smoke and hazardous particles in the air.

Out of all of these months, May came in as the cleanest with its reading of 20.5 μg/m³, color coded as yellow in its moderate ratings bracket, which requires a PM2.5 reading of anywhere between 12.1 to 35.4 μg/m³ to be classified as such.