Air quality in Hull

What is the air quality index of Hull?

Kingston upon Hull, which is usually abbreviated to Hull, is a port city situated in the East Riding of Yorkshire, England. It stands on the banks of the River Hull and the Humber Estuary. The 2019 estimated population was 259,778 people.

At the start of 2021, Hull was enjoying some “Good “quality air with a US AQI reading of 42. This is in line with the classifications from the World Health Organisation (WHO). The concentration levels of the pollutants were as follows: PM2.5 - 10.2 µg/m³, PM10 - 13.5 µg/m³, nitrogen dioxide (NO₂) - 9.4 µg/m³ and sulphur dioxide (SO₂) - 0.5 µg/m³. With such relatively low levels of pollution, doors and windows can be opened to allow the flow of fresh air and outdoor activities can be enjoyed without fear.

Looking back at the figures from 2019 it can be seen that Hull achieved the WHO target figure of less than 10 µg/m³ for 6 months of the year. During four other months, air pollution could be seen to be “Good” with figures between 10 and 12 µg/m³. For the remaining 2 months of the year, the figure was between 12.1 and 35.4 which classified it as “Moderate”. Throughout the year the average figure was 10.9 µg/m³ which ranked Hull as the 34^th dirtiest city in the UK.

Does the level of air quality differ in Hull throughout the year?

Generally speaking, air quality is very often worse when the weather is cold. Cold air is denser than warm air and therefore sinks down to a low position. As it does so, it traps any suspended air pollution which finds it difficult to escape. Because it is held at lower levels it means more people have the chance to inhale it. Air pollution in winter remains in place for much longer and therefore is breathed in at a higher rate than during the summer.

Warm air is often more laden with moisture. Cold air can’t hold as much, and so the air is usually drier during winter. One of the more curious air pollution facts is that rain can eliminate a large part of it. As rain falls it has the effect of washing the air as it carries any particles with it towards the ground. This is less likely to occur in many areas during winter because precipitation levels are lower. Without this cleansing effect, the air doesn’t lose its pollutants and instead remains contaminated. This prevents the natural cycle that removes dust from the air and prevents more from entering the atmosphere. If you look at air pollution in summer vs winter, you see that cool, dry air holds more pollution. This causes more irritation and breathing difficulty than it would in summer when the air is more mobile.

Another factor to take into account is that more heat is needed in the cooler winter months to heat up the spaces in our homes. Wood-burning stoves have become very popular but they are notorious for polluting the air with fine particulate matter.

What is the main source of air pollution in Hull?

Following on from figures taken in previous years, it is seen that nitrogen dioxide (NO₂) is still the main pollutant. The main source of this chemical is from the incomplete combustion of diesel in cars and other diesel-powered vehicles/equipment. Back in the 90s, driving a diesel car was considered to be better for the environment than gasoline-powered cars. They are now seen in a different light as a great source of PM2.5 pollutants. People are now recommended to buy an electric or hybrid car.

Often overlooked is the fact that fireworks are often used when celebrating and these surprisingly contribute a significant amount to air pollution. In just one year, Hull recorded an astonishing 128 deaths due to poor air quality and was said to be the worst offender in the region.

Levels of nitrogen dioxide (NO₂) are monitored which is a key pollutant mainly produced by vehicle exhausts. A network of around 90 diffusion tubes are used, which are small plastic tubes that can be attached to lamp-posts and road signs, and are collected and changed over once a month. This can often be a good indication as to just how much nitrogen dioxide is produced by vehicles because the further away from the main road you go, the lower the levels of NO₂.

What can be done to improve the air quality in Hull?

There are currently 40 UK cities on a list which states the quality of their air as being substandard. Albeit, Hull is low down on the list, but it is still on it.

The City Council is encouraging residents to use public transport, in particular, public buses. These are gradually being replaced by low or zero-emission buses. Car sharing or carpooling is also being encouraged but it is proving to be unpopular.

What are the effects of breathing Hull’s poor quality air?

Air pollution is associated with a number of adverse health impacts. It is recognised as a contributing factor in the onset of heart disease and cancer. Additionally, air pollution particularly affects the most vulnerable in society such as children under the age of 14 years, senior citizens, pregnant women and those with pre-existing illnesses and heart and lung conditions. There is also often a strong correlation with equalities issues because areas with poor air quality are also often the less affluent areas of the city. The majority of carbon dioxide comes from vehicle emissions.

Generally, if you are young and healthy, moderate air pollution levels are unlikely to have any serious short term effects. However, elevated levels and/or long term exposure to air pollution can lead to more serious symptoms and conditions affecting human health. This mainly affects the respiratory and inflammatory response systems, but can also lead to more serious conditions such as heart disease and cancer.

The adverse health effects due to polluted air have been widely publicised. Most world governments recognise this fact and are taking active measures against it. Air pollution has also been recognised by doctors as one of the world’s highest 10 killers seeing some 29,000 premature deaths in the UK every year and some 430,000 worldwide.