Ban on the single-use plastic items came into effect in the State on January 1, 2019, and the Corporation had seized more than 300 tonnes of banned plastic till December 2019. "We were taking action against the shops using single-use plastic items during the start of 2020. However, due to the pandemic, we could not concentrate on the banned plastic. Our entire workforce, especially of the health department, is deployed for COVID-19 control works," a Chennai Corporation official said.