The concentration of noxious gas carbon monoxide (CO) was found to be on a higher level at M.G. Road here even after the lockdown came into force, revealed a study by the State Pollution Control Board (SPCB).
“It is important to note that the concentration of CO is found to be on a higher level at the air quality monitoring station at M.G. Road. This may be due to the unauthorised usage of diesel generator sets in close proximity and local burning of garbage, etc., especially during the lockdown period. It is a usual practice of the public to dispose of non-biodegradable waste through burning, which generates higher concentration of CO and Particulate Matter (PM),” said the report prepared by the regional office of the SPCB in Ernakulam. However, the daily data on concentration of different parameters showed a downward trend during the lockdown period. This may be due to the effect of reduction in traffic intensity and shutdown of different facilities, especially industries and the construction sector that usually generate higher concentration of parameters such as particulate matter (PM 10 & PM 2.5), oxides of nitrogen, sulphur dioxide and carbon monoxide during the lockdown period, it said.
Air quality index
Even though the carbon monoxide level was found high, the air quality index at M.G. Road was now in the range ‘good and satisfactory’ (AQI range 0-50 and 50-100 respectively).
The maximum air quality index observed was in the range of ‘moderate’ (AQI Range 100-200) during normal times.
The air quality index at Vyttila during the lockdown period was rated as ‘good’. However, the data during the lockdown period showed a predominance of nitrous oxide emissions. It may be due to the proximity of the bus terminal, where a lot of vehicles are parked. But, detailed investigations have to be carried out to check how the nitrous oxide levels increased in these times.
At Eloor, the levels of particulate matter remained high even during the lockdown period while a descending trend was noticed in the levels of SO2, CO, and NOx. The AQI level was recorded as ‘satisfactory’. This may be due to the temporary shutdown of certain industrial units in addition to limited usage of vehicles, according to the study.
