However, with lifetime soot emissions of greater than 100 automobiles, this is clearly not the case. Environmental, public health, and community groups are increasingly concerned about the optimistic industry announcements of the arrival of this new technology. Unfortunately, announcements regarding diesel-electric hybrid buses fail to address the most serious health risks of diesel exhaust and a number of critical issues related to the operation, maintenance, and cost of these new buses. In this document, we summarize the health risks of diesel exhaust, raise a number of critical concerns about the current wave of diesel-electric hybrid bus demonstration projects, and offer a series of recommendations for transit operators and regulators who are trying to gauge the environmental performance of these new buses. Some people are at greater risk from diesels hazardous mix, including children, the elderly, people with respiratory conditions or who smoke, and people who exercise, work or live near diesel exhaust sources.
Diesel exhaust is a major source of fine particles, especially in urban areas.
Over half of all particulate matter in Manhattan comes from a relatively small number of diesel tailpipes. Under the same engine and load conditions, diesel engines emit 100 times more particles than gasoline engines. Numerous public health studies have found links between fine PM and a wide variety of health impacts, including increased asthma hospitalizations and emergencies, chronic bronchitis, pneumonia, heart disease, and even premature death. Nitrogen Oxides . NO x is a primary precursor in the formation of ground-level ozone, a major component of urban smog.