April 19, 2007
U.S. E85 use could worsen public health, study says
Palo Alto, California – Fleet-wide use of E85 in the U.S. could increase the number of respiratory-related deaths and hospitalizations, according to a new study by Stanford University professor Mark Jacobson. His findings were published in the journal Environmental Science & Technology, as reported by the Green Car Congress.
Jacobson combined an air pollution and weather forecast model with future emission inventories, population data and health effects data to examine the effect of converting from gasoline to E85 on cancer, mortality and hospitalization, both in the U.S. as a whole and Los Angeles in particular.
The study found that, after accounting for projected improvements in vehicle emission controls, E85 may increase ozone-related mortality, hospitalization and asthma by about 9 per cent in Los Angeles, and 4 per cent in the U.S. as a whole, relative to 100 per cent gasoline. While the simulations found that E85 vehicles reduced atmospheric levels of two carcinogens, benzene and butadiene, when compared to gasoline vehicles, the E85 vehicles increased levels of two other carcinogens, formaldehyde and acetaldehyde. As a result, cancer rates for E85 are likely to be similar to those for gasoline.
Jacobson says that future E85 may be a greater overall public health risk than gasoline, due to its ozone effects, but because of the uncertainty in future emissions regulations, he can only conclude with confidence that E85 is unlikely to improve air quality over future gasoline vehicles. The projected health effects of E85 are the same regardless of the feedstock or process used to create it.