Qualité de l’air à Plymouth

What is the air quality index of Plymouth?

Plymouth is a port city on the south coast of Devon, England. It is 310 kilometres south-west of London. It stands on the banks of two rivers, the River Plym and the River Tamar which, together form the Plymouth Sound which acts as a natural barrier between Devon on Cornwall. Following a census in mid-2019 the estimated population was found to be just over 250,000.

At the beginning or 2021, Plymouth was enjoying a period of “Good” quality air with a US AQI reading of 36. This is according to the recommendations by the World Health Organisation (WHO). The concentrations of the pollutants were as follows: PM2.5 - 8.8 µg/m³, PM10 - 22.8 µg/m³ and nitrogen dioxide (NO₂) - 3.6 µg/m³. With levels as relatively low as these, doors and windows can be opened to let in the fresh sea air and all types of outdoor exercise can be enjoyed without fear.

What is the main source of air pollution in Plymouth?

Air quality in Plymouth is generally good and there were very few areas where levels of nitrogen dioxide (NO₂) exceed the recommended levels by the government. These concentrations are largely related to road traffic emissions which like so many other major cities is one of the main causes of air pollution in our urban areas. Diesel fumes are the main source of fine particle pollution in modern cities.

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

Back in 2018, Plymouth was classed as one of the UK’s most polluted cities. The data showed 31 cities in the UK had fine particle air pollution levels above 10 µg/m³, the target set by the WHO. The fine particle readings for Plymouth were 12 µg/m³, exceeded only by seven other cities.

Apparently the European Union has taken legal action against the UK on three previous occasions due to excessive pollution levels.

Closing streets to traffic outside primary schools and creating safe routes for children to walk and cycle to school to help improve air quality has been suggested. Children are particularly vulnerable to air pollution and it is important we normalise active travel to make our cities cleaner and the people living in them healthier.

It is well-known that vehicles are the major source of air pollution in modern cities. Plymouth council have taken measures to try and redress the balance. These include improvements to the road network to reduce congestion at junctions, greater support for walking, cycling tracks and public transport, supporting the increased use of electric cars by providing charging points, increasing taxi emission standards and upgrading the city’s bus fleet to cleaner fuel vehicles. Ultimately looking for zero-emission vehicles and zones throughout the city.

Local authorities in the South West are being urged to introduce ultra-low emission zones to charge drivers in city centres and ban the use of wood burning stoves and coal fires in areas where air pollution exceeds guidelines.

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

Research shows that death from air pollution is 16 times more frequent than deaths from traffic accidents.

Air pollution in Plymouth has been linked to 108 deaths in just one year. The latest data shows that over four per cent of deaths in the city during 2017 were attributed to the deadly toxin, PM2.5, which often comes from coal and vehicle emissions.

Because of its microscopic size, the human body cannot filter the PM2.5 particles because they bypass the body’s natural defence mechanism and it can cause respiratory and carcinogenic problems if breathed in over a sustained period of time.

As much as 50 per cent of deadly PM2.5 toxins generated in cities and large towns come from sources such as wood burning stoves and coal fires. Unfortunately wood-burning stoves are thought of as being “trendy” at the moment and as such are a very popular auxiliary form of heat. Depending on the source of the wood, they can be a very reasonable way of providing heat and hot water for households.

Not all of the PM2.5 pollutants are locally generated because some in the south of England is blown in from continental Europe.

What is the level of air pollution in Plymouth?

Looking back at figures from 2019, it can be seen that Plymouth enjoys reasonably good quality air throughout the year. From July until the end of October Plymouth achieved the WHO target figure for air quality of less than 10 µg/m³. In February and again in April the air quality was classed as “Moderate” with figures between 12.1 and 35.4 µg/m³. For the remaining six months the air quality was “Good” with figures between 10 and 12 µg/m³. Looking back to previous years, in 2017 the reading was within the WHO target at 9.3 µg/m³. In 2018 the figure rose slightly to 10.1 µg/m³ and in 2019 the average annual figure was 11.1 µg/m³.

Is shipping a major source of air pollution in Plymouth?

Shipping is often seen as a large cause of pollution because of the sheer size of the vessels, but in reality it is one of the greenest methods of freight transport because of strict rules on the sulphur content of the fuel and the use of technology such as scrubbers which wash the emissions from the machinery.

No vessel is permitted to discharge those wastewater tanks into the harbour. This is known as a closed loop system. There is insufficient evidence to suggest either one way or another as to the safety of these two systems but port authorities are taking no chances until more information is known.

Some other large ports generate clean electricity for the ships in berth so they do not need to use their own fuel whilst in dock. This might be a consideration for the future.

All employees working for the Port authority qualify for assistance with the purchase of a bicycle if they require one. This reduces the volume of vehicles on the roads and encourages cycling, thus reducing the emissions caused by commuting.

Various other measures have been introduced to reduce emissions in and around the port. Water is being used to wet the areas so that the dust will not rise into the air. Electric vehicle are to be purchase for use on the dock side.

Hauliers are not permitted to idle their motors whilst on the dockland, and all existing forms of light are to be replaced by energy-efficient LEDs.