Aarti Drugs Ltd. is suspending the chlorosulfonation process at the PTSCL section of its T-150 unit in Tarapur, Maharashtra, following directions from the Maharashtra Pollution Control Board (MPCB). The move comes after a minor hydrochloric acid (HCl) gas leakage incident on September 8, 2025.

In an exchange filing, the company reported that the leakage occurred through the manhole of a scrubbing tank during the chlorosulfonation process. No injuries or casualties were reported.

“During chlorosulfonation process at the PTSCL section at T-150 unit, the HCl gas is generated continuously, which is absorbed in the water scrubber using a chilled falling film system. During this operation, an incident of HCl gas leakage through the manhole of the scrubbing tank occurred on September 8, 2025,” it said.

The company confirmed that no injuries or casualties were reported. 

Following the incident, the company received an order from the MPCB on September 9, 2025, directing it to voluntarily shut down the chlorosulfonation process at the PTSCL section as a precautionary and safety measure. In compliance, Aarti Drugs said it would stop chlorosulfonation operations once the in-process batches are completed.

The company clarified that the move will not have any financial or material impact, and manufacturing of the other products at the T-150 unit will remain operational.

“The manufacturing of PTSCL is for captive consumption as well as direct sale to customers. The company has enough inventory of the said product and is well equipped to procuring the same from other suppliers if required,” it said.

Aarti Drugs added that it will soon conduct a safety audit and obtain the required approvals from the MPCB and the Directorate of Industrial Safety and Health (DISH) before resuming operations.