The Tamil Nadu Pollution Control Board (TNPCB) has asked tyre manufacturers to reduce the content of carbon black in tyres, which is the second most important component in rubber tyres.

“This material too contributes to road dust that is a reason for ambient air pollution. Due to wear and tear of tyres on roads, the carbon black is released and mingles with the dust. This only adds to the pollution caused by polycyclic aromatic hydrocarbons caused by improper combustion from vehicles. Though better roads can reduce the wear and tear on tyres, for now we are tackling tyre manufacturers,” said a source in the TNPCB.

Carbon black, which is a black powder or granular substance made by burning hydrocarbons in a limited supply of air, helps in abrasion resistance and also adds to the strength of the tyre. The largest use of carbon black is in the manufacture of automotive tyres, explained a tyre industry expert.

“We are asking manufacturers in the State too to reduce carbon black, which accumulates on the road. In cities like Chennai where pollution levels are slowly climbing up, such steps will help keep pollution in the ambient air under control,” the TNPCB source added.

Tyre industry sources said that though carbon black cannot be eliminated completely, globally many tyre companies were reducing the quantity used. It has its uses and so is a very essential component in tyres.

“In developing countries too such steps are being taken. Adding silica helps in many things including in improving wet grip resistance. Companies have already begun reducing carbon black in the case of special tyres,” a source said.