WHO says there is a definite link between diesel exhaust and cancer

CSE says India must pay heed to the findings and stop state-sponsored homicide by allowing uncontrolled use of dirty diesel

NEW DELHI, June 14, 2012: The International Agency for Research on Cancer (IARC), a wing of the World Health Organization (WHO), has said that diesel engine exhaust can certainly cause cancer, especially lung cancer in humans. Responding to this shocker from the WHO, Centre for Science and Environment (CSE) has asked: “Is India prepared to respond to the public health risk of diesel?”

This finding comes at a time when India has failed to adopt a clean diesel road map, prevent use of under-taxed and under-priced toxic diesel in cars, and reduce its overall consumption in all sectors. Says Anumita Roychowdhury, head of CSE’s air pollution control unit: “India must note that this decision has come from a rigorous review of the latest scientific evidence on the cancer-causing potential of diesel and petrol exhausts. Evidence on diesel's toxicity has been mounting over the past 20 years, which has already compelled stringent regulatory action on diesel quality and emissions standards in other regions of the world.”

What the IARC has found

The IARC has reclassified diesel exhaust and removed it from Group 2A list of `probable carcinogens` to its Group 1 list of substances that have definite links to cancer – thus changing its status to ‘carcinogen’. Diesel exhaust is now in the same class of deadly carcinogens as asbestos, arsenic or tobacco among others.

In its release, IARC-WHO has said that their decision is unanimous and is based on compelling scientific evidence. The most clinching evidence has come from one of the largest American studies in March this year by the US National Cancer Institute. This study has analysed 12,300 miners for several decades starting 1947 and found that miners heavily exposed to diesel exhaust had a higher risk of dying from lung cancer.

The IARC-WHO has urged worldwide efforts to reduce exposure to diesel fumes as much as possible.

This is certainly a wake-up call to India which is in the grip of rapid dieselization, says Roychowdhury. While people are exposed to both motor vehicle exhausts as well as to exhausts from other diesel engines and uses, there are special concerns over diesel vehicles as they release emissions within the breathing zone of people. In a city like Delhi, more than 55 per cent of its 17 million people live within 500 metres of major roads and are directly affected by traffic emissions.

India trading cancer for profit

When the Indian auto industry makes claims of modern diesel engines, it omits to say that health concerns have driven governments in Europe, the US, Japan and other countries to leapfrog to clean diesel. Diesel is considered relatively cleaner when advanced emissions control systems are used with diesel fuel with 10 ppm sulphur content. But the diesel sulphur level in India is as high as 350 ppm. Only a few cities have 50 ppm sulphur diesel – which is five times higher than the global benchmark.

It is extremely worrying that even after the implementation of the Auto Fuel Policy in 2010 which introduced Bharat Stage III in the country and Bharat Stage IV in 13 cities, the government of India has not set the next target for moving quickly to Euro VI emissions standards. Therefore, new automobile production and investments in the country are not even linked to any further commitment to improving vehicle technology and fuel quality. This will significantly delay adoption of clean diesel technology in the country and add to the toxic risk. In fact, by the end of the 12th Plan, the so called modern diesel technology in India will be 17 years behind Europe!

Even the limited evidences in India point towards high contribution of diesel fuel combustion in cities to the formation of tiny killer particles – PM2.5 (particulate matter less than 2.5 micron in size). A World Bank supported study on source apportionment of PM2.5 in selected Indian cities, released in 2004, shows that depending on the season, the contribution of diesel fuel to the total PM2.5 ambient concentration can be as high as 61 per cent in Kolkata, 23 per cent in Delhi and 25 per cent in Mumbai. Dieselisation will also add to the burden of particulate matter, nitrogen oxides, and ozone -- the key pollutants of concern in Indian cities. The current emissions standards in India legally allow diesel cars to emit more particulate matter and nitrogen oxides.

India’s cancer registry says cancer is taking on an epidemic form that demands immediate action to cut environmental risks. Perpetrating the use of conventional diesel will add to this cancer burden. The cancer-causing potential of diesel particulates and emissions is several times higher than some of the worst known air toxics. For instance, the number of excess cancer cases per million people per microgramme per cubic meter diesel particulate emissions concentration over a 70-year lifetime exposure is 300. This is several times higher than dangerous toxics like 1,3-Butadiene which is 170.

The IARC-WHO statement sends out a strong signal for urgent and stringent action. But in India, dieselization has taken off at a maniacal pace with state subsidies. Despite recession, diesel cars have clocked 34 per cent growth last year and are close to 60 per cent of new car sales. How can the government justify the hidden subsidies to the rich and to a killer fuel?

Early response from other governments

Globally, governments have responded to the science of diesel toxicity. The California Air Resources Board had identified diesel exhaust in 1990 as a chemical known to cause cancer and after an extensive review in 1998, listed diesel exhaust as a toxic air contaminant. The US National Institute for Environmental Health Sciences added diesel particulates to its list of substances that are reasonably anticipated to be human carcinogens, in its ninth national toxicology report on carcinogens. In fact, a multiple air toxics exposure study conducted by the South Coast Air Quality Management District in California found that diesel particulates pose 70 per cent of the cancer risk in southern California.

Europe also began to introduce clean diesel with 10 ppm sulphur and particulate traps from the time of Euro IV emissions standards that are currently in force in 13 Indian cities. In fact, the data available from Europe for urban traffic shows that diesel and petrol cars meeting the same level of emission norms have different toxicity levels. The toxicity is several times higher for diesel emissions even as the emissions standards are progressively tightened.

CSE demands

The rapid increase in use of under-priced and under-taxed toxic diesel in cars without corrective action on quality of diesel and restraints on its overall use virtually amounts to state-sponsored homicide. Public health costs must figure in diesel’s balance sheet. Cancer cannot be traded for profit.

  • Effectively high additional taxes on diesel cars to fully neutralise the incentives that diesel cars get from the low taxed diesel fuel. CSE has sent missives to the ministries of finance and also to the ministry of petroleum and natural gas demanding effectively high additional taxes on diesel cars to fully neutralise the incentives that diesel cars get from the low taxed diesel fuel.
  • Immediately announce the timeline for introduction of clean diesel technology and fuels nation-wide.
  • The revenue from the additional tax should be ploughed back to meet the cost of refinery upgrade to produce 10 ppm sulphur diesel nation-wide.

For more on this, call Papia Samajdar at 9811906977 or write to her at papia@cseindia.org.