An analysis of air quality index values compiled by the Goa State Pollution Control Board for 2017-18, shows that air quality has been worsening in the cities and towns.
Vasco remains the most polluted city in the state followed by Ponda, Panaji, Mapusa and Margao.
The air quality is slowly deteriorating in these towns and cities due to high density of vehicles and construction activities.
Most monitoring stations recorded an AQI above 100 and 201-classified ‘moderate’, and at a few locations the air quality was recorded as ‘poor’.
According to the GSPCB analysis, Panaji, Vasco, Mapusa, Margao and Ponda do not comply with the annual permissible concentration of PM10 of 40µg/m³, as prescribed by the Central Pollution Control Board under the National Ambient Air Quality Standards.
PM2.5 concentration was also found exceeding in Panaji, Vasco and Mapusa.
Among the cities and towns where data was measured, the ambient air quality was within the NAAQ limits during monsoon.
Although the concentration level of sulphur dioxide is within permissible limits of 80 mpmc, the figures indicate that the levels of NOX have been increasing slowly.
The level of nitrous oxide, which is released from a vehicle, was recorded between 10µg/m³ and 19µg/m³ from April 2017 and March 2018.
The vehicle emissions and the burning of waste in open have been the main cause of air pollution in Vasco; as a result the level of PM10 exceeded two times in November last year and between January and March this year, which was over and above 240 mpmc.
The daily prescribed standard for PM10 is 100mpcm but desirable is 60 mpcm.
In fact, the air quality has touched to the scale of ‘poor’ , sending bad news to those having breathing problems.
The air quality in Ponda has gone for a toss. The levels of PM10 for the period from January and March this year were 50-60 per cent higher than the daily standard and almost thrice the annual standard.
The air quality from June to September last year remained good but in November it started deteriorating as dust stirred up on roads due to frequent movement of vehicles.
The number of vehicles on the roads in Panaji is always high. With this being the case, it is not surprising that for eight months, air quality standards in the state capital were above the daily permissible limit of 100 µg/m³ of PM10 concentration.
The city air quality was marked between ‘moderately polluted’ and ‘satisfactory’ on the air quality index. In May, last year the air quality became worse – on the air quality index it was recorded going down from ‘moderately polluted’ to ‘very poor’.
Last year, in May and December, the levels of PM10 rose to 314 mpmc. However, this year from January to March the levels increased on nine occasions.
In Mapusa, particulate matter ‘10 micrometers in size’ has gone up by over two times from the national air quality
The impact of rampant construction is evident on the air quality of Mapusa which shows PM10 hovering between 120mpmc and 218mpmc from November 2017 and March 2018.
The air quality monitoring stations in Margao recorded ‘satisfactory’ readings as of March.
In October 2017 the PM10 was recorded at 116 mpcm giving ‘moderately polluted’ reading.