[roflwaffle]

Originally Posted by Big Dave

All that is left are extremely expensive measures that will not result in noticeable improvement.

Maybe those who die prematurely aren't noticeable to you, but they are to others, which is what it was considered worthwhile.

Increased Cancer Risk from Diesel Exhaust More than 30 human epidemiological studies have found that diesel exhaust increases cancer risk. One major study examined the effects of diesel exhaust exposure on more than 56,000 railroad workers over a 22-year period.10 Calculations based on this study showed that chronic exposure to just one microgram per cubic meter of diesel exhaust particles—roughly the level found in many suburban areas far distant from trucking routes or ports—would result in an additional risk of 1.3 to 15 cancer cases per 10,000 exposed individuals. Using that finding as a benchmark, the South Coast Air Quality Management District in California calculated that fully 71 percent of the cancer risk due to air pollution in the South Coast Air Basin is attributable to diesel particulate pollution. Agencies in a number of other areas have reached similar conclusions.

Dozens of studies have shown that long-term exposure to diesel exhaust significantly increases the risk of lung cancer. In fact, workers exposed to diesel exhaust over the long term generally face an increase in lung cancer risks of between 50 and 300 percent.13 Studies have also reported links between diesel exposure and other cancers, including cancer of the bladder, kidney, stomach, blood (including multiple myeloma, leukemia, Hodgkin’s disease, and non-Hodgkin’s lymphoma), the oral cavity, pharynx, and larynx. A number of federal and international agencies have listed diesel exhaust as a probable or likely lung carcinogen, and in 1990, the state of California listed diesel exhaust as a known cause of lung cancer.

Diesel engines emit a complex mixture of air pollutants, composed of gaseous and solid material. The visible emissions in diesel exhaust are known as or PM. In 1998, California identified diesel exhaust particulate matter (PM) as a toxic air contaminant based on its potential to cause cancer, premature death, and other health problems. Diesel engines also contribute to California's fine particulate matter (PM2.5) air quality problems. Those most vulnerable are children whose lungs are still developing and the elderly who may have other serious health problems. Based on year 2000 emissions in California, diesel PM contributes each year to 2000 premature deaths and thousands of hospital admissions, asthma attacks and other respiratory symptoms, and lost workdays. Overall, diesel engine emissions are responsible for the majority of California's known cancer risk from outdoor air pollutants. In addition, diesel soot causes visibility reduction and is a potent global warmer.

From here and here. Majority rules and minority rights.