• Energy Research
• 3. Good health close

Ethanol use in vehicle fuel is increasing worldwide, but the potential cancer risk and ozone-related health consequences of a large-scale conversion from gasoline to ethanol have not been examined. Here, a nested global-through-urban air pollution/weather forecast model is combined with high-resolution future emission inventories, population data, and health effects data to examine the effect of converting from gasoline to E85 on cancer, mortality, and hospitalization in the United States as a whole and Los Angeles in particular. Under the base-case emission scenario derived, which accounted for projected improvements in gasoline and E85 vehicle emission controls, it was found that E85 (85% ethanol fuel, 15% gasoline) may increase ozone-related mortality, hospitalization, and asthma by about 9% in Los Angeles and 4% in the United States as a whole relative to 100% gasoline. Ozone increases in Los Angeles and the northeast were partially offset by decreases in the southeast. E85 also increased peroxyacetyl nitrate (PAN) in the U.S. but was estimated to cause little change in cancer risk. Due to its ozone effects, future E85 may be a greater overall public health risk than gasoline. However, because of the uncertainty in future emission regulations, it can be concluded with confidence only that E85 is unlikely to improve air quality over future gasoline vehicles. Unburned ethanol emissions from E85 may result in a global-scale source of acetaldehyde larger than that of direct emissions.

This study quantifies worldwide health effects of the Fukushima Daiichi nuclear accident on 11 March 2011. Effects are quantified with a 3-D global atmospheric model driven by emission estimates and evaluated against daily worldwide Comprehensive Nuclear-Test-Ban Treaty Organization (CTBTO) measurements and observed deposition rates. Inhalation exposure, ground-level external exposure, and atmospheric external exposure pathways of radioactive iodine-131, cesium-137, and cesium-134 released from Fukushima are accounted for using a linear no-threshold (LNT) model of human exposure. Exposure due to ingestion of contaminated food and water is estimated by extrapolation. We estimate an additional 130 (15–1100) cancer-related mortalities and 180 (24–1800) cancer-related morbidities incorporating uncertainties associated with the exposure–dose and dose–response models used in the study. We also discuss the LNT model's uncertainty at low doses. Sensitivities to emission rates, gas to particulate I-131 partitioning, and the mandatory evacuation radius around the plant are also explored, and may increase upper bound mortalities and morbidities in the ranges above to 1300 and 2500, respectively. Radiation exposure to workers at the plant is projected to result in 2 to 12 morbidities. An additional ∼600 mortalities have been reported due to non-radiological causes such as mandatory evacuations. Lastly, a hypothetical accident at the Diablo Canyon Power Plant in California, USA with identical emissions to Fukushima was studied to analyze the influence of location and seasonality on the impact of a nuclear accident. This hypothetical accident may cause ∼25% more mortalities than Fukushima despite California having one fourth the local population density due to differing meteorological conditions.