The ambient air quality in the city has plunged as traffic continues to crawl on congested roads and construction works have reached a peak.

The dry summer days have made things worse with pedestrians and two-wheeler riders often being seen using masks or covering their faces.

Kerala State Pollution Control Board sources said that one of the reasons for the surge in suspended particles in the air could be the metro rail construction activities, a charge denied by Delhi Metro Rail Corporation, which is overseeing construction activities with its contractors.

An SPCB official said that the recent 24-hour average of particulate matter over Kochi crossed 100 micrograms per cubic metrewhere as the safer level was an average of 60 micrograms. The results were from the Vyttila monitoring station of the Pollution Control Board, the official said.

The situation could be worse in Kaloor, where metro rail construction is in full flow, the official said pointing out that a meeting with Kochi Metro Rail authorities on February 12 had seen the issue being raised. KPCB had issued directions that water be sprayed around construction sites to reduce dust.

The KPCB official also said that severe traffic congestion in the city could be another reason for unhealthy level of particulate matter over the city.

Idling vehicles on congested roads is a serious cause for pollution, the official said.

Earlier, KPCB took up the issue of air pollution with KMRL after a Kochiite filed a complaint. He was called for a hearing by the Board chairman K. Sajeevan where representatives of KMRL, DMRC and construction contractors were present.

KMRL sources said that the issue of rising dust levels in the air had been taken up with DMRC, the latter assuring that instructions would be issued to the contractors to take steps for dust reduction.

DMRC sources said that air pollution from metro rail construction activities had come down drastically because most of the superstructure works were complete.

Chances of metro rail construction activities increasing pollution rose only on the stretch of road between Vyttila and Kadavanathara on SahodaranAyappan Road and near the Jawaharlal Nehru International Stadium, near Kaloor.

DMRC sources also said that the city roads affected by construction activities were expected to be fully restored before the monsoon and handed over to the Corporation of Kochi.