The Brihanmumbai Municipal Corporation has demolished four chimneys of gold and silver smelting units in Kalbadevi and Zaveri Bazar area in South Mumbai amid worsening air pollution in the city, officials said on Wednesday.

According to BMC officials, their C-ward took action against the units as they were compounding the air pollution in the metropolis.

Mumbai’s average air quality index (AQI) stood at around 150, or "moderate", on Wednesday, according to official data.

As part of the business of making ornaments and allied activities, gold and silver are melted in smelting units, which are mostly small-scale factories. While the precious metals are melted in a furnace, gaseous byproducts are released into the air through chimneys, civic officials said.

However, when such fumes are released without scientific treatment, they pose a threat to human health, they said.

As these hazardous gases add to the city’s pollution, BMC has initiated a drive against those violating the air pollution norms, said a civic official.

The BMC’s buildings and factories department has evicted four such smelting units on Dhanji Marg and Miza Marg in C-ward, the official said.

According to a BMC release issued on Wednesday, Maharashtra Chief Minister Eknath Shinde has directed the civic body to take measures to bring air pollution and dust under control in Mumbai.

Acting on the directive, the BMC has started taking measures in all 24 civic wards, including cleaning nearly 650 kilometres of road with water for dust control, it said.

The civic body recently issued new guidelines to lessen air pollution in the city. It has given developers and those carrying out infrastructure work a month’s time to acquire sprinklers and fogging machines for their construction sites and also warned of stern action in case of non-compliance.

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