Lagos ranks 133 in the world’s most polluted cities
Lagos State, Nigeria’s commercial capital and most populous state, has been ranked 133 in the world’s most polluted cities in a historical data of 2017-2022, according to a report by IQAir.
The air quality index of Lagos
Lagos with an estimated population of the metropolitan area was 21 million people as of 2018, has the concentration of its PM2.5 pollutant as 73.2 µg/m³.
According to US AQI, Lagos was said to be “experiencing some rather poor quality air with a US AQI figure of 160 which classified it as ‘unhealthy’ according to recommended figures from the World Health Organisation” at the beginning of 2021.
Furthermore, the report says that with such level of poor air, “it is recommended that a good quality mask is worn when going outside.
Doors and windows should be kept closed so as to prevent the ingress of polluted air in the home. All types of outdoor exercise should be abandoned until air quality improves.”
In addition, IQAir states the main source of air pollution in Lagos to come from vehicle emissions, closely followed by industry and domestic energy use.
“Every day, 227 vehicles clog each kilometre of road. Most of these vehicles are over 15 years old and are not equipped with the latest emission technologies.
The fuel they use has a very high sulphur content which is 200 times higher than U.S. standards for diesel,” the report says.
Industrial emissions are the second source of air pollution in the city of Lagos. Industrial and commercial zones such as Apapa, Idumota, Ikeja and Odogunyan, where cement, chemicals, furniture, oil refineries, steel processing industries are concentrated, have high levels of pollution.
“In Odogunyan, a PM2.5 concentration of 1,770 µg/m³ was recorded in a period of 24 hours,” it noted.
Also, the report noted that half of Lagos’ total energy needs are supplied by generators which are yet another source of air pollution.
And the poor combustion of the gasoline and oil used to power the generators pollutes the air and could cause huge health damage.
“The use of energy such as charcoal, wood and kerosene in cooking, makes the problem difficult in rural areas due to limited infrastructure and access to clean energy.”
Which measures can be taken to improve the air quality in Lagos?
The report suggests regular inspections of automobiles to ensure that older cars are not releasing harmful chemicals into the atmosphere. It adds that Nigeria must remove cars that are toxic to the environment from the road.
Also, it sees the introduction of efficient electric energy as a means to decrease the need for generators, which produce unhealthy air in households and work environments.
“Nigeria has access to sustainable energy resources that are capable of providing power to its citizens.
These methods are safer for the environment and the usage of them decreases the use of gasoline-powered generators, thus decreasing pollution,” it states.
Additionally, rural areas in Nigerians can reduce air pollution in the household by substituting fuelwood, coal and charcoal for biogas, which is a form of biofuel that is made from the decay of natural waste.
Biogas will provide sustainable options for preparing food and heating the household at the same time eliminating air pollution both inside the household and the outside environment.
“Lagos is making some progress in introducing laws but they still need to be executed. In 2017, standards for sulphur content in fuel were lowered to reduce emissions: from 3,000 parts per million (ppm) to 50 ppm for diesel; and from 1,000 ppm to 150 ppm for gasoline.
“Emissions from industries could be lowered with the use of newer, better technologies such as solar power. The garbage situation needs to be addressed due to the huge amount of rubbish that is buried, burned or just dumped.
Teams need to monitor this situation and act accordingly when the perpetrators are caught. Much of the plastic could be recycled instead of being burnt as it is now.
Furthermore, daily waste removal from households would also help to properly dispose of garbage, which reduces the fragmentation of waste and prevents odours forming that contribute to air pollution,” according to the report.
What are the effects of breathing Lagos poor quality air?
The report notes that “Ambient air pollution is caused by pollutants such as nitrogen oxides (NOx), sulphur dioxide (SO2), ozone (O3) and fine particulate matter with an aerodynamic diameter of less than 2.5 micrometres or PM2.5.
These are dangerous because they can easily bypass the body’s natural defence system and enter the bloodstream, contributing to mortality and morbidity.
While the WHO guideline for the annual mean PM 2.5 concentration level is 10 µg/m³, Lagos has recorded levels of 68 µg/m³ in the same range as other polluted megacities such as Beijing, Cairo and Mumbai.”