Uniform pollutant norms in the air
The government’s new air quality standards will soon blur the divisions between industrial and residential areas, reports Chetan Chauhan.Updated: Jan 07, 2008 03:00 IST
The government’s new air quality standards will soon blur the divisions between industrial and residential areas. These norms — based on the pollutant’s impact on human health — will be uniform and will replace the land-use based types.
At present, more pollutants are allowed in the air for residents in industrial areas like Shahdara as compared to those in residential colonies like Greater Kailash.
“It was felt that there is no need to have area based classification because of difficulties in enforcement and the right of all citizens to have similar benefits of superior air quality,” a Central Pollution Control Board (CPCB) official explained.
The new norms prepared by the country’s pollution watchdog are based on acceptable health risk from pollutants derived from empirical studies conducted in the last three years. “To arrive at acceptability of risks, carcinogenic air pollutants associated with excess lifetime cancer risk of 1 per one lakh cases was considered acceptable,” the official said.
While deriving the acceptable level of pollutants, it became apparent that the present air quality levels were harmful for human health.
The new norms prescribe maximum of 40 unit grams of nitrogen dioxide (considered carcinogenic) in a cubic metre area as compared to 80 for industrial areas and 60 for residential. Similarly, the new norm for sulphur dioxide is 50 ug/m3 as compared to present standard of 80 for industrial and 60 for residential.
Those who are asthmatic would know, for the first time, whether the air they are breathing is safe for them or not. The CPCB has introduced standards for finer respirable suspended particulate matter (RSPM) also called PM 2.5, directly related to asthma attacks. Concentration of 40 ug/m3 has been considered safe. Till now, the norm was only for SPM also called PM 10, which has not been changed.
In the soon-to-be-notified norms, standards have also been introduced for toxics like benzene, arsenic, mercury, nickel and vanadium and trace gases like ozone considered highly carcinogenic. “We can now get the real picture of how lethal is the air we breathe,” said Anumita Roy Chowdhury of the Centre for Science and Environment.
Along with humans, there will be pollution level norms for plants as well. The CPCB has prescribed 30 ug/m3 as annual concentration level of sulphur dioxide for agriculture crops and 30 ug/m3 of nitrogen dioxide for forests and natural habitation.
“It is recommended that the mean concentration value should not exceed because the higher levels cause slowing down of crop, especially during winter months,” says the draft on new air quality standards.
The new standards will take Indian air quality standards to that of Europe but its enforcement and monitoring is still a concern for environmentalists.
“Unlike America, where financial incentives from the federal government to the states are linked with improvement in ambient air quality, that is not the case in India. Targets are set to improve air quality but they are normally not met,” she said.
Once enforced within a few months, environmentalists say, the citizens would be able to assert their right to breathe “healthy air”.