Qualité de l’air à Kochi

What is the air quality index of Cochin?

Cochin is also known as Kochi or Cochi is a major seaport on the south-west coast of India. It is one of the most populous regions in the state of Kerala with an estimated population of 2.2 million people in 2011.

At the beginning of 2021, Cochin was experiencing poor air quality with a US AQI reading of 122 which classes it as “Unhealthy for sensitive groups” according to recommended figures by the World Health Organisation (WHO). The recorded concentrations of the main pollutants were as follows: PM2.5 - 44 µg/m³, PM10 - 48 µg/m³, nitrogen dioxide (NO2) - 6.4 µg/m³ and sulphur dioxide (SO2) - 6.4 µg/m³. With levels such as these, the advice is to close doors and windows to prevent the ingress of dirty air. Those of a sensitive disposition are advised to remain inside or if travel outside is unavoidable, then a good quality mask is recommended. It is recommended that all unnecessary outdoor exercise is postponed until the air quality improves.

What is the main source of Cochin’s polluted air?

As is often the case, the main source of air pollution here comes from vehicle exhaust fumes and power station emissions.

A study on air and travel-related pollution caused by urban transportation rated Cochin as the fifth cleanest city out of 14 which were tested. In particular, levels of particulate matter PM2.5 and PM10 were examined, together with levels of nitric oxide (NOx) and heat-trapping carbon dioxide (CO₂) in relation to energy consumption used in the daily commute. The critical indices of motorisation, the volume of travel demand based on the population, the share of different modes of transport in meeting the travel demand were also taken into account. The quality of vehicle technologies and transport fuels was also considered for comparative analysis.

Does air pollution in Cochin differ throughout the year?

As with many places, the air quality in Cochin is often worse during the dry season. The main reason being is that there is very little rainfall which would normally clean the air by washing away the suspended pollutants. In January and February 2019, figures were recorded between 55.5 and 150.4 µg/m³ which classed it as “Unhealthy”. For the remaining 10 months, the figures were between 12.1 and 35.4 which put it in the “Moderate” bracket. It showed a marginal improvement over the 2018 figure of 28 µg/m³ with a 2019 mean of 27.9 µg/m³.

Temperature inversion often occurs in the colder months which traps polluted air nearer to the ground.

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

Bharat Stage emission standards are standards for regulating air pollution emitted from internal combustion and equipment of engines and spark-ignition engines.

These standards are intended to improve three areas (emissions control, fuel efficiency and engine design).

The central government made it mandatory for vehicle manufacturers to manufacture, sell and register only BS-VI (BS6) vehicles with effect from 1^st April 2020. BS-VI is designed to conform to Euro-VI norms.

As per BS-VI emission norms, 25 per cent of nitrogen oxide (NO_x) emissions are given to petrol vehicles, 43 per cent to diesel engine vehicles to hydrocarbons and nitrogen oxide (HC and NO_x) and 68 per cent to their NO_x levels and particulate matter levels had to be reduced by 82 per cent.

The presence of sulphur content in the fuel is a major cause for concern. The amount of sulphur in BS-VI fuel is much less than that of BS-IV fuel. It is reduced from the prescribed dose of 50 mg/kg under BS-IV to 10 mg/kg in BS-VI.

Some of the measures introduced after 2023 will include in-service compliance by regulatory authorities, market monitoring and auto vehicle testing and public disclosure of emission data on websites by manufacturers, etc.

What are the health risks associated with Cochin’s poor quality air?

Every year 349,681 women in South Asia are deprived of maternity pleasure due to air pollution, which is about 7.1 per cent of the pregnancy loss in the region. Researchers believe that if the level of air pollution in the region is limited to 40 µg/m³, then the lives of these people can be saved.

Significantly, this level of air pollution is the same that has been recognised as the standard of PM2.5 in India. Which means that if the level of air pollutant PM2.5 present in the air is less than 40 µg/m³, then it is safe for health.

Although this estimate of 7.1 per cent loss is based on India's air quality standard (40 µg/m³), the risk increases to 29 per cent if we look at WHO's 10 µg/m³, standard.

Bangladesh, India and Pakistan are already well-known for poor air quality worldwide. Increasing air pollution in these countries is affecting the health of pregnant women. Research has shown that exposure to poor air quality increases the risk of stillbirth and miscarriage.

South Asia is the most densely populated region worldwide. Where the level of air pollution PM2.5 is much higher than the WHO recommendations. Also, due to limited health facilities, the rate of pregnancy loss is also the highest in the world. This is the reason that pollution here affects the health of women the most during pregnancy.

The research is based on data from health surveys conducted between 1998 and 2016. In which the data obtained from satellites is taken to understand the risk of PM2.5 during pregnancy. A model has been designed to understand how exposure to PM2.5 increases the risk of pregnancy loss for women. It has also taken into account the long term trends related to woman's age, temperature and seasonal variations.

Air pollution is certainly not new to the world. You can gauge how big the risk of air pollution is from the fact that every year around 9 million people worldwide die prematurely due to air pollution. Whereas, on an average, it is reducing the life of the survivors by three years, on average. According to the World Health Organisation, more than 90 per cent of the world's population is forced to breathe air that is not right from the health point of view.