The West Bengal Pollution Control Board (WBPCB) has started using a suppressant chemical that will stop dust resuspension and keep the spiking air-quality index in check during winter.
The chemical will be mixed with water and sprayed along the road to coalesce finer particles into bigger ones to keep them grounded for long. A Central Pollution Control Board (CPCB) study shows over 30% dip in particulate concentration in the air following the use of dust-suppressant chemical.
“We were wary of the health impact of the dust suppressant chemical. This is why we sent samples to the National Test House and the Indian Institute of Toxicology Research. Both the organisations have given clearance as far as public health is concerned. Moreover, the chemical is non-inflammable. So we will be using it across the city and recommend other civic bodies to follow suit,” said WBPCB chairman Kalyan Rudra.
Significantly, the source apportionment study and emission inventory study — carried out by NEERI — had earlier revealed that road dust is the source of 66% of PM10 pollution. Road dust is also a major contributor to PM2.5 pollution.
“We will be running the vehicles across major corridors of the city. Each vehicle will cover 50km in each trip. So, our three vehicles will cover 150km in the morning and another 150km in the evening. But we are going for re-tendering so that we can deploy more such vehicles,” said WBPCB member secretary Rajesh Kumar.
At each site, particulate matter concentration would be monitored before and after the dust suppressant is sprinkled. PM10 and PM2.5 concentration will be monitored each time at different time intervals (10 minutes, one hour, two hours, three hours and six hours) after sprinkling the dust suppressant to understand the duration of its efficacy.
A CPCB study showed 50% to 60% initial reduction in dust concentration 10 minutes after spraying the suppressant. About 30% drop in dust concentration was observed after six hours.
WBPCB has already provided Rs 6 crore to KMC for procurement of 10 water sprinklers and 10 mechanical sweepers.
Source: Times of India