Rains elevate Kolkata's air quality by several notches

Kolkata, Jul 9 (PTI) Heavy rains, which lashed Kolkata for the past two days, improved air quality by several notches as the pollutants got cleansed in the showers, a senior West Bengal Pollution Control Board (WBPCB) official said on Wednesday.
    The Air Quality Index (AQI) was reported 'good' in several pockets of the metropolis.
    While the AQI was recorded 26 PM 2.5 at the Rabindra Sarobar automated air monitoring station, it was 60 (PM 2.5) at Ballygunje and 50 at Jadavpur at 6 pm of Wednesday in the southern parts, the official said.
    In Victoria Memorial area, the AQI was 44 while it was recorded 51 in Rabindra Bharati University and 42 in Bidhannagar air station in northern parts of the city.
    In Botanical Gardens air monitoring station, across the river Bhagirathi in Howrah city, a known pollution hotspot, the AQI was 45 during the same time.
    While the AQI within 50 is interpreted as 'good' in the environment parlance - free and fresh from toxins - it is considered moderate between 51-100.
    Good AQI is considered satisfactory with minimal or no health risks while AQI in moderate zone is overall acceptable barring those with respiratory conditions.
    The rains cleansed pollutants in the air by reducing pollution level by several notches and elevated air quality as a result bringing it to 'good' or 'moderate' level.
    The AQI was 'poor' between June 26 and July 2 when the city was gripped by hot and humid conditions before the onset of monsoon interrupted by sporadic rains, the official said.
    In environment parlance the AQI is classified as poor from 101-150 indicating significant air pollution that can cause breathing discomfort for most people, especially those with pulmonary issues, particularly children and elderly persons and prrolonged exposure may lead to potential health risks.
    From July 2 to July 7, the AQI turned satisfactory reading between 51-100 limits in most places and between 30-50 in three others, he said..
    On July 8, the AQI hovered between 26-60 across different air monitoring stations.
    Heavy rain lashed several southern districts of West Bengal, including Kolkata on that day.
    "If there are few more spells of rain the AQI will remain so or further slide by a few notches," the official said.
    The India Meteorological Department (IMD) has forecast light to moderate rainfall at most places, with isolated heavy to very heavy rainfall over some districts of West Bengal, owing to a low-pressure along with a strong monsoon flow. The low-pressure area over Gangetic West Bengal is likely to move slowly west-northwestwards across Jharkhand and north Chhattisgarh during the next two days.

(This story has not been edited by THE WEEK and is auto-generated from PTI)