via The Guardian
For several years scientists were puzzled why Delhi was more susceptible to thick smogs than other polluted cities such as Beijing. New research links this to tiny chloride particles in the air that help water droplets to form. Globally, chloride particles are mainly found close to coasts, due to sea spray, but the air in Delhi and over inland India contains much more than expected.
At first, the sources were thought to be illegal factory units around Delhi that recycle electronics and those that use strong hydrochloric acid to clean and process metals. These are certainly part of the problem, but new measurements have revealed another source.
Read the full story here: https://www.theguardian.com/environment/2021/feb/26/not-just-oceans-plastic-polluting-air-delhi-smog