Press Note: CSE analyses recently released six-city study on air pollution sources from environment ministry, finds flaws in it

Says auto industry misusing the study to derail tighter emissions standards and encourage polluting diesel cars

  • The Union ministry of environment and forests’ (MoEF) recent study in six Indian cities to assess the contribution of various sources to air pollution is something the country has been eagerly waiting for. The seminal study was mandated by the Auto Fuel Policy of 2003 with the aim of deciding India’s future emissions standards roadmap for vehicles and fuels. Naturally, there is a lot at stake.

  • CSE’s analysis reveals that this study is a victim to bad science and damaging politics. The auto industry and the oil companies have begun to use the results of this study selectively to prove that vehicles are not the problem and diesel vehicles even lesser so. They are blaming cooking gas (LPG) as the biggest polluter in Delhi! This is being done to keep the standards lenient and to protect diesel cars from harsher fiscal measures.

  • CSE’s analysis shows that if toxic particulate emissions from only the combustion sources are considered, then vehicles’ contribution to PM10 load can be as high as 83 per cent in Chennai, 63 per cent in Bangalore and 53 per cent in Pune; in Delhi, it would be the third major contributor.

  • Though the study has been carried out by different agencies, the industry is quoting only those done by the National Environmental Engineering Research Institute (NEERI) for Delhi and Mumbai. These studies have blamed LPG and road dust for Delhi’s air pollution. Why has the ministry accepted the unsubstantiated and scientifically untenable findings of NEERI?

  • It will be criminal if the government allows manipulative use of this study and ignores health evidences of vehicular pollution. Recent global studies show that in Delhi, more than 50 per cent of the population lives within the influence zone of vehicular traffic and emissions. One study says that a hike in particulate levels can increase premature deaths by as much as 3,000 a year in Delhi.

  • CSE calls for stringent post-2010 emissions standards roadmap for vehicles and aggressive tax measures in the forthcoming budget to put a brake on diesel cars and SUVs. 

New Delhi, February 8, 2011: Centre for Science and Environment (CSE) has pressed the alarm bells over the auto industry’s efforts to use a questionable study to deflect policy attention from vehicles, especially diesel cars. Titled ‘Air quality monitoring, emission inventory and source apportionment study for Indian cities’, this study has been released recently by the MoEF.

Says Anumita Roychowdhury, CSE’s executive director-research and advocacy and head of its air pollution control unit: “The automakers are selectively taking advantage of the weak science of the Delhi and Mumbai components of the study. This is unacceptable, when the country is poised to make use of this same study to decide the post-2010 emissions standards roadmap for vehicles and fuels.”

She adds: “The country is also waiting to take decisions on the tax measures in the forthcoming budget to halt misuse of diesel subsidy on diesel cars and SUVs.”

The 2003 Auto Fuel Policy had asked for an extensive city-specific study: the MoEF’s six-city report is a result of that. It includes emissions inventories of PM10, NOx and SO2 and source apportionment of PM2.5.

But with only a few weeks left for the Union Budget, the Society for Indian Automobile Manufacturers (SIAM) has begun to cite this study to defend diesel cars and to prove that overall, vehicles are not the problem. There are other instances as well in which both the vehicle industry and oil companies are using the same study to understate the problem of vehicular pollution.

It is curious that though five different agencies have carried out independent studies for the six cities of Delhi, Mumbai, Chennai, Bangalore, Kanpur and Pune, the industry is citing only the emissions inventory and source apportionment studies done by the NEERI for Delhi and Mumbai.

What is wrong in the NEERI study?

  • The NEERI study for Delhi and Mumbai grossly underestimates vehicles’ contribution to both PM10, PM2.5 and NOx compared to other cities.

  • NEERI blames LPG combustion as one of the biggest contributors to PM2.5 – as much as 61 per cent in industrial locations, 49 per cent in residential locations and 41 per cent on roadside. The other big contributor, according to them, is road dust. A quick review of all source apportionment results from other studies in India and Asia, however, show LPG is not a major contributor to particulates.

  • While NEERI finds high contribution of LPG to PM2.5 in Delhi, other agencies have found none in the remaining cities. What is so unique about LPG combustion in Delhi that it dominates the PM2.5 pollution in the city? Neither NEERI nor the MoEF have explained this. They have not given any indicator or the chemical markers used to assess LPG’s contribution to particulates to justify such high contribution.

  • An even bigger gaffe is that while LPG is being said to be up to 60 per cent of the PM2.5 problem in Delhi, NEERI has not found any trace of LPG in PM10 (that includes the PM2.5 fraction)! This is impossible and defies any scientific judgment. How could such claims pass the technical and scientific scrutiny of the environment ministry?

  • Even more curious is the mysterious disappearance of the PM2.5 source apportionment study done by NEERI for Mumbai from the ministry’s final report. In NEERI’s presentations in international forums on the results of this study, it has shown LPG’s contribution to PM2.5 in Mumbai. But that study, done with public money, has been quietly withdrawn without any explanations. If the science of this study is under fire, so should be the one done for Delhi.

  • It is also evident that the environment ministry has only loosely added the NEERI PM2.5 source apportionment study in their synthesis report without integrating it with the overall conclusions and recommendations of the six-city study. Therefore, despite NEERI blaming LPG, the ministry fortunately recommends replacement of solid fuels with LPG as a strategy to combat pollution and improve health. This raises many questions about the overall intent and science of the NEERI study. The ministry needs to explain the quality of the technical peer review of a report that allows such gaffes to go unchallenged.


Enough clinching evidences in the six cities to push for hard action
CSE’s analysis also shows clearly that despite the weaknesses of the NEERI reports and other discrepancies, the assessment from other cities have thrown up enough clinching evidences that justify urgent and aggressive action.

  • Contribution of vehicles to pollution load is significantly high: The assessment of vehicles’ contribution to NOx is decisive – in most cities, it varies between 45 to 94 per cent. The report also notes that “NO2 levels are much higher at kerbside locations indicating clear influence of vehicles… Delhi once again shows the highest pollution at kerbside locations compared to all other cities” (page 23).

  • Scary when particles from only combustion sources are considered: The detractors have tried to confuse the share of vehicles in particulate pollution by clubbing it with road dust that always is high. But even with that, the PM10 inventory in Bangalore shows vehicles contribute as much as 41 per cent, and in Kanpur 22 per cent. There is nothing unusual about road dust dominating the particulate inventory.

  • High share of vehicles reestablished: If only the combustion sources are considered in the PM10 inventory, vehicles’ share increases dramatically. The industry ignores this and understates vehicles’ contribution to particulates.

  • The report states “……PM2.5 has much higher component of toxic elemental carbon and organic carbon that mostly come from combustion sources like vehicles and others” (page 196). Also “…the presence of hopanes and steranes (chemical markers) at all the sites in much higher quantities compared to background locations indicates that effect of vehicles is prevalent at all the sites of Delhi” (page 43).

  • Study acknowledges the health problems: “Several epidemiological studies have linked PM10 and especially PM2.5 with significant health problems. PM2.5 is of specific concern because it contains a high proportion of toxins, and … penetrate deeper into the lungs. Therefore, while planning control strategies greater emphasis is to be given on reduction of PM2.5 and toxic constitutes of particulates” (page 197).


Government must also act on the new health evidences in Delhi
A new study conducted by the US-based Health Effects Institute shows that in Delhi, more than 50 per cent of the population lives within the influence zone of vehicular traffic and emissions. The study says that the effect of vehicular fumes is the maximum up to 500 to 1,500 meter from the roadside. This means maximum people are at risk from vehicular fumes.

Yet another study coordinated by the same agency shows approximately 0.15 per cent to 0.17 per cent increase in mortality per 10 microgram per cubic meter (μg/m3) of PM10. This means the total premature deaths due to air pollution can be as much as 3,000 a year in Delhi.

Do not let industry perpetrate dieselisation of cars
The industry is trying everything to stop diesel cars from paying right for fuel as well as pollution costs. It is misleading to say that diesel cars currently form a small part of the existing on-road fleet. Diesel cars are already 36 per cent of the new car sales – the figure will soon reach 50 per cent. The CSE analysis shows rapid introduction of diesel car models even in the smaller segments.

With the growing chasm between petrol and diesel prices, diesel car sales is bound to explode -- since 2008, the petrol price in Delhi has increased by Rs 12.75 but diesel price has gone up by only Rs 4.89 a litre. The price gap has increased from 28 per cent in 2008 to 35 per cent now. The under-recovery -- the revenue that the oil companies are losing on diesel today -- stands at Rs 7 per litre.

The government continues to incur a huge revenue loss as it earns much less from excise on a litre of diesel used by cars, as opposed to petrol. Revenue losses will compound not only with increased share of diesel cars and SUVs but also with greater penetration of diesel in the smaller car segments. Cheaper diesel fuel will encourage more diesel cars, more driving and more fuel guzzling in the rebound.

The forthcoming Union budget will have to put the fiscal brakes on increased use of diesel in cars as well as prevent the shift towards bigger cars and SUVs. The auto industry’s claim of greater fuel efficiency and lesser carbon emissions from diesel cars is misleading, as diesel fuel has higher carbon content than petrol. As more cheap diesel is burnt, more heat-trapping CO2 will escape. At the same time, black carbon emissions from diesel cars can trap several times more heat and cause warming.

The way ahead
It is a myth that vehicular -- and especially diesel car -- technology available currently in India is clean and meets the public health objectives. Instead of confusing the issues with bad science, the government must immediately act to get a robust roadmap and fiscal measures to get clean vehicle technology and fuels. 

  • The six city study must immediately catalyse decision on early nationwide introduction of Euro V/VI emissions standards. This study has already suggested control options for vehicular emissions over the time-frame of 2015 and 2017. This includes progressive incremental introduction of BS IV from 2010 onwards; progressive incremental introduction of BS V/VI from 2015 onwards and complete the process by 2017, electric vehicle to be 2 per cent of the city fleet, all commercial three and four wheelers to be on CNG/LPG, and 20 per cent shift in vehicle miles traveled to public transport among others.

  • Need tax reform to remove incentive for diesel cars: Industry cannot be allowed to scuttle tax measures to prevent dieselization of the car fleet. Remove price incentive for diesel cars. Equalise fuel taxes and prices. Or levy higher taxes on diesel cars to neutralize the effect of cheap fuels and persuade people to consider cleaner alternatives. A year has lapsed since the recommendation of the Kirit Parikh Committee to have additional excise taxes for diesel cars.

  • Do not allow the misuse of the six-city study: The environment ministry must immediately explain NEERI’s claims on LPG combustion being the biggest polluter in Delhi, its scientific basis and remove all distortions and inconsistencies emanating from the study that is expected to secure public health in the country. 

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