Plastic bags less than 120 micron in thickness are banned in the state from Saturday, December 31, according to a state government notification, but Kolkata's markets are still filled with bags that are way thinner.
The ban on any plastic product less than 120 micron in thickness is a step-up from a previous ban on anything less than 75-micron thick, which came into effect on July 1.
A waste management expert said thicker bags are used more times, they are easier to collect and waste collectors want to pick them up because of their recycling value. Single-use plastic, a term used for thin plastic products, has none of these advantages, which is why it should be phased out.
Many Kolkatans said the use of single-use plastic had significantly dropped immediately after the July 1 ban. Shopkeepers had stopped giving plastic bags less than 75 microns in thickness.
"They were wary that they would be prosecuted for using single-use plastic. They were giving cloth bags or asking buyers to bring a bag from home. But after a month everyone became relaxed and the use of single-use plastic returned in full force," said a Kolkatan.
The authorities never tried to enforce the ban, said another Kolkatan.
Kolkata Municipal Corporation (KMC), which is empowered to fine anyone using banned plastic bags, did not impose any fine though such plastic is being widely used in full view.
Swapan Samaddar, mayoral council in charge of the KMC's environment department, said "the KMC has not imposed penalties on anyone".
"We are trying to stop the use of single-use plastic. I will talk to the mayor about whether we should start imposing penalties now," he said.
The KMC can impose a penalty of Rs 500 on any trader using single-use plastic and Rs 50 on a buyer.
Residents from across the city told The Telegraph that in the last month they had been given single-use plastic bags by traders selling flowers, groceries, vegetables, fish and chicken.
"Single-use plastic bags are used openly. No one is even afraid of using them," he said. Single-use plastic bags cost less than the bags that are 120 micron or more in thickness, a reason why small traders want to buy them. The manufacturers of plastic bags have little capital to work with.
"To shift from making a plastic bag that is 50 micron or less in thickness to making a bag 120-micron thick will need some modification in machineries. Many manufacturers, who work with little capital, are finding it difficult to make the investment. They are waiting for some handholding from the government," said Suneel Pandey, director of the waste management division at The Energy and Resources Institute (Teri).
Officials of the state environment department and the KMC have said several times that the gradual increase in the thickness of plastic products, below which everything is banned, is done so that manufacturers and suppliers get time to dispose of products already manufactured.