Climate change and the epithelial barrier theory in allergic diseases: A One Health approach to a green environment

Various environmental factors have taken an enormous toll on global health and have made allergic diseases including asthma, dermatitis and food allergies into a major health concern. Non-communicable diseases, of which allergic diseases are the most prevalent, suffer adverse effects due to global warming and climate change. With this in view, sustainable consumption and production of consumer items was a major topic of discussion at the G20 Summit under India’s presidency, the article notes.

The Epithelial Barrier Theory suggests that industrialisation and modernisation have led to the human ‘exposome’ to be negatively affected through contact with a growing number of toxic substances that disrupt the epithelial barriers of the skin, airways and gut mucosa. ‘Exposome’ refers to “all environmental factors individuals encounter throughout their lifetime.” These include climate, urban or rural settings, education level, lifestyle choices, metabolism, inflammation, oxidative stress, exposure to pollutants and infectious diseases.

Citing a 2020 meta-analysis studying chemical pollution, the article states that since the 1960s, more than 350,000 new substances have been introduced in human lives without adequate control over their toxicity. Such substances include particulate matter, diesel exhaust particles, cigarette smoke, nano- and microplastics, ozone, carbon monoxide, nitrogen dioxide, sulphur dioxide and various surfactants.

Epithelial barriers are also damaged by common chemical agents found in consumer products like toothpaste, shampoo and detergents. Damaged barriers increase the chances of bacteria, toxins, pollutants and allergens entering the respiratory and gastrointestinal tracts.

Government policies that help to reduce fossil fuel usage and increase biodiversity are of extreme importance, the article notes. It suggests mitigation measures including improvement in the energy efficiency of buildings, and a more sustainable transportation system. This, the article states, will contribute to reducing people’s exposure to toxic substances.

Focus and Factoids by Akriti Kanodia.

PARI Library's health archive project is part of an initiative supported by the Azim Premji University to develop a free-access repository of health-related reports relevant to rural India.