The inspections carried out by the Environmental Surveillance Centre of the Kerala State Pollution Control Board in Eloor here to check the efficiency of odour control systems in bone meal units, chicken waste rendering plants and rubber processing units in the Edayar industrial area have revealed poor emission control units and shortcomings in the maintenance of existing biofilter units for odour mitigation.

Notices have been served on seven of the 20 such units under the provisions of the Air (Prevention and Control of Pollution) Act, 1981, as of September 1, 2026. The action was taken after the elected representatives and environmentalists in Eloor municipality and Kadungalloor panchayat demanded immediate action against erring units at a meeting convened by the board on Monday.

The board officials stated that the inspections found lapses mainly in the operation and maintenance of odour control measures. As per the directives issued by the board, the chicken waste rendering plants, fish oil, animal waste and rubber processing units have to install appropriate air pollution control systems, comprising a biofilter with biomedia for odour control.

The inspections showed that the shortcomings linked to biofiltration efficiency occurred due to improper selection of filling material and poor operation of the biofilter. The improper operation and maintenance of the existing biofilter were among the key reasons for the emission of odour and volatile organic compounds into the atmosphere at the time of processing the raw material and plant operation, they said.

The erring units were also found lacking in housekeeping measures as per norms. Lack of cleanliness and poor housekeeping were detected during the inspections. The units lacked adequate facilities for storage of raw material. Some of the units lacked proper ventilation and refrigeration system for raw material storage.

V. Narendra Kumar, president of the Edayar Small-Scale Industries Association, said that the compliance level in relation to the odour emissions has improved in the majority of the units after steps were taken to install the required measures prescribed by the Pollution Control Board. We have asked all the member units to plug lapses, if any, without delay, he said.

A study report by the CSIR-National Institute for Interdisciplinary Science and Technology (NIIST), Thiruvananthapuram, published in September 2023 had revealed that odour and volatile organic compounds were being released from the erring units during raw material processing and plant operation owing to the poor operational efficiency of the units.