Indoor air pollution in India
In the previous post we provided information about outdoor air pollution. The problem of indoor pollution was also briefly introduced there. This blog post will provide more in depth information about indoor pollution and focuses on its major causes and scale of the problem. In addition, we will take a closer look at how indoor air pollution is related to the non-communicable diseases COPD and asthma and the communicable diseases tuberculosis and lower respiratory infections, which form the double burden of respiratory diseases in India (see our previous blog posts for more information about those diseases).
Indoor air pollution is “the world’s largest single environmental health risk” according to the WHO. Indoor pollution in high income countries (HICs) is primarily caused by asbestos, pesticides, heavy metals, volatile organic matter, and environmental tobacco smoke. Low- and middle income countries (LMICs), on the other hand, experience most indoor air pollution as a consequence of combustion of solid fuels, such as firewood, (char)coall, dung and crop waste.
The global burden of Disease study, published in the Lancet, identified indoor air pollution as the leading risk factor for deaths in LMICs. It is estimated that in 2017, worldwide 1.6 million people died prematurely as a consequence of indoor air pollution (3% of all deaths). Among LMICs, India bears the highest burden (28% needless deaths). In 2017, indoor air pollution was responsible for 4,86% of deaths in India (see figure 1). However, India did make progress regarding deaths related to indoor pollution. The death rates in India dropped from 140.87 per 100,000 in 1990 to 51.03 deaths per 100,000 in 2017 (relative change of -64%).
Despite the aforementioned decline, still 56% of the indian population is exposed to indoor air pollution as a consequence of combustion of solid fuels, making India is one of the countries with the largest population lacking access to clean fuels. Around 80% of the indian rural households still heavily rely on biomass fuels for cooking. Most commonly used fuels for cooking and heating in India are firewood (49%), liquefied petroleum gas (LPG; 28.6%) and cow dung cake (8,9%). The incomplete combustion of these biofuels result in the production of particulate matter (PM10 and PM2,5), which causes an adverse effect on our health. These adverse health effects will now be elaborated.
The particulate matter from the incomplete combustion can penetrate the airway, which causes or worsens respiratory infections, chronic bronchitis and COPD. In addition, nitrogen dioxide and sulfur dioxide, which are also products of the incomplete combustion of fuels, causes and exacerbates wheezing in asthma patients. Moreover, a study shows that the asthma prevalence amongst elderly was higher when using biomass fuels in comparison with the use of cleaner fuels. We can thus conclude that indoor air pollution contributes to the double burden of respiratory diseases.
Besides elderly, important high-risk groups for indoor air pollution and the thereby belonging respiratory diseases, are children and women. In India, it is culturally established that women take care of the cooking, exposing them to higher rates of particulate matters. In addition, women are also expected to look after the children. In order to combine their cooking tasks with looking after the children, the children also spend a lot of time in the kitchen, exposed to the harmful incomplete combustion products.
Now that the size of the problem and the risk groups are identified, it is important to know what kind of policies are established to tackle the problem of in- and outdoor pollution. In 2019, India launched the National Clean Air Programme (NCAP). The goal of this programme was to reduce the particulates matters by 20–30% by 2024. The programme especially focuses on strengthening monitoring networks and generating citizen awareness. Even though the programme looks promising at first glance, there are a few important limiting factors. First of all, now one year after its development, it still lacks the legal enforcements of its targets. Without any legal mandate, the implementation of the NCAP is almost impossible. Furthermore, it lacks adequate financing capacity, which hinders the implementation of the programme. So, a more adequate strategy to solve these hurdles is needed to effectively fight the burden caused by air pollution.
This blog post was written by Jippe Miedema