TEAM HERALD
teamherald@herald-goa.com
PANJIM: Though traditionally, the focus has always been on poor air quality in mining areas, the situation in city and towns is showing increased levels of pollution, Goa state Pollution Control Board data shows.
Also there is an increase in content of heavy metals such as lead and nickel in water that can have potential ill effects if fish from these waters is consumed. Goa state Pollution Control Board records show that levels of sulphur dioxide in the capital and Vasco da Gama are showing an increasing trend, though they are still well within permissible limits. Also waters of the river Mandovi at the Ferry Point showed an increase in the levels of heavy metals such as nickel, chromium, lead, besides that of calcium, sulphates and chlorides, studies by the Goa State Pollution Control Board have revealed.
Data also shows that while in 2009-10 levels of SO2 (in air) were 2.95 µg/m3, these have now reached 9.75 µg/m3 as 2012-13 and has increased almost three fold. This goes against a national trend in cities like Delhi and Mumbai where there is a decreasing trend in ambient sulphur dioxide levels due to various interventions such as reduction of sulphur in diesel, use of cleaner fuel such as CNG etc.
In Goa there have been no such interventions and the number of petrol and diesel vehicles is only increasing.
However, this is still way below the limit of 80 µg/m3 and there is a chance for the state to rectify it.
The Goa Pollution Control Board conducts ambient air quality monitoring at Panjim, Vasco, Mapusa, Margao, Ponda and at Kundaim Industrial Estate. While monitoring in Panjim, Vasco and MPT have been around for a long time, whereas monitoring at Mapusa, Margao, Ponda and Kundaim Industrial Estate has been initiated since 2010.
The Board has also reported that while the ambient air quality monitoring trend during 2010 to 2012 reported that particulate matter levels were very high and exceeding permissible limits, but during 2012-13 (after mining was stopped) the levels of particulate matter have come down to a great extent and are now within the prescribed permissible limits.
Pollution was noticed at Mapusa Tar, Carambolim lake, St Cruz, Cuncolim, Curchorem where the water bodies were used for visarjan (immersion).
Samples of water collected at the Mandovi Ferry Point before the Ganesh visarjan showed levels of 0.01, 0.01, and 0.05 milligram per litre of nickel, chromium and lead respectively. However after the Ganesh visarjan the data shows that these levels increased ten fold to read 0.12, 0.16, and 0.25 of nickel, chromium and lead.
Heavy metals produce bright and rich colours when combined with sulphates, etc to form salts. Hence these salts of metals are used to produce bright colour paints.
In cities like Delhi and Mumbai where there is a decreasing trend in ambient sulphur dioxide levels due to various interventions. In Goa there have been no such interventions and the number of petrol and diesel vehicles is only increasing.
