Carcinogenic Effects of Diesel Emissions and LAC

Lyon, France, June 12, 2012. After a week-long meeting of international experts, the International Agency for Research on Cancer (IARC), which is part of the World Health Organization (WHO), today classified diesel engine exhaust as carcinogenic to humans, based on sufficient evidence that exposure is associated with an increased risk for lung cancer.

There have been concerns about the cancer-causing potential of diesel exhaust for several decades. After a thorough scientific review of the most recent information, IARC found that diesel exhaust is a cause of lung cancer (sufficient evidence) and also noted a positive association (limited evidence) with an increased risk of bladder cancer (Group 1). A Group 1 categorization is used when there is sufficient evidence of carcinogenicity in humans.

Because of increasing environmental concerns over the past two decades, tighter emission standards for both diesel and gasoline engines have been implemented in North America, Europe and elsewhere. This also required other changes such as marked decreases in sulfur content, changes in engine design to burn diesel fuel more efficiently and reductions in emissions through exhaust control technology. However, in less developed countries regulatory measures are less stringent or even absent. This is despite the required technologies necessary for reduction of sulfur to near-zero levels being available and the refining industry continuing to make progress in developing more efficient processes for removal of sulfur.

The new classification is of direct relevance to Latin America where air pollution concentrations in many cities exceed the World Health Organization (WHO) standards and the use of older diesel vehicles and high sulfur fuels is still widespread.

According to data published in June 2012 by the United Nations Environment Programme (UNEP) on “Status of Fuel Quality and Vehicle Emission Standards in Latin America and the Caribbean” Chile, Costa Rica, Puerto Rico and Virgin Islands are the only countries in the Latin America and Caribbean region which currently utilize low sulfur diesel fuel (sulfur levels below 50 ppm). Other countries across the region are in the process of transitioning towards low sulfur fuels, but this is happening too slowly whilst other countries have no regulatory plans in the pipeline.

Studies show the benefits of sulfur reduction far outweigh the costs, even though required refinery investments can be significant. The U.S. EPA found human health and environmental benefits, due to sulfur reduction, can be ten times higher than the costs. Moreover, the considerable potential for greenhouse gas emission reductions adds further to the health, environmental, and social benefits of sulfur reduction.

As well as low sulfur fuels there are other actions that developing countries can take to reduce exposure to harmful emissions. These include:

  • Accelerate the introduction of ultra low sulfur diesel and low pollutant emission vehicle technologies (especially carcinogens).
  • Expand and improve mass public transportation systems.
  • Improve freight transport systems, including engines, bodies and driving practices, as well as logistics.
  • Implement scrappage programs for older model vehicles that pollute more, including cars, trucks and transit vehicles.
  • Legislate so that vehicle inspection and maintenance are mandatory and enforced.

The Clean Air Institute is seeking to tackle these issues through its Sustainable Transport and Air Quality (STAQ) program funded by the Global Environment Facility and the World Bank. The Program’s regional objectives in LAC are: a) to establish a network of local and national governments, stakeholders, international organizations and private sector entities to promote policies and actions leading towards more energy efficient and cleaner urban transport systems in Latin America, b) to assist cities to develop sustainable urban transport strategies that integrate climate change and air quality components and c) to improve capacities of cities to quantify the impacts of transport policies on climate change and air pollution emissions.