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Environmental Tobacco Smoke
Read the US Surgeon General's Report How Tobacco Smoke Causes Disease

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Environmental > Engine Idling

Idling vehicles produce exhaust fumes that are bad for health and environment. Vehicles that run on diesel fuel contribute a disproportionate amount of air pollution and toxic risk: specifically, oxides of nitrogen, fine particulate matter (PM 2.5 and PM 10) and air toxics. School buses that run on diesel fuel are notable polluters.

The fine particulates of diesel fuel can bypass respiratory defense mechanisms and lodge deep in the lungs, impairing lung function. While prolonged exposure to particulate matter is a factor in reducing overall life expectancy by a few years, short-term exposure is associated with increased risk of death from heart attacks or other cardiovascular events. Diesel fumes may enhance the effects of some allergens among sensitive individuals. Children, because of their proximal relationship to diesel-powered school buses and their quick metabolisms, are at particular risk.

There is some evidence that diesel emissions not only exacerbate asthma but that prolonged exposure can cause asthma and can set-up a propensity for asthma in the unborn. Even ordinary car emissions–including but not limited to diesel exhaust–can damage the DNA of fetuses while they are still in the womb.

Idling Myths
Idling is old habit propped up by many myths that need to be dispelled. For instance, idling one's vehicle for 10 seconds will use more fuel than turning the engine off and re-starting as needed. At an average of $3 per gallon for gas and $3.25 for diesel fue,l idling vehicles waste $37 million dollars in fuel each year, according to the the Environmental Defense Fund calculations.

Idling Laws
Most states have idling laws that target heavy duty vehicles, and to a lesser extent other vehicles. In NYC, there is 3-minute limit on all vehicles citywide and a 1-minute limit near schools. School buses are not allowed to idle near schools. A range of NYC agencies can enforce the idling laws (as of April 2009):  NYPD's Traffic Enforcement Agents, Department of Sanitation, and the Department of Parks & Recreation are able to issue tickets, in addition to the Department of Environmental Protection. 

Ice cream trucks, which run diesel refrigeration units, often idle for long periods of time near schools and playgrounds. NYC principal can ask idling vehicle, such as ice cream trucks, to move away from the school.

Associations of PM2.5 and black carbon concentrations with traffic, idling, background pollution and meterology during dismissal time.
By Jen Richmond-Bryant et al.
Science of the Total Environment (1/09)
AFSZ AQ study (2006-07 in NYC's East Harlem.

air quality

Idling Gets You Nowhere: The health, environmental and economic impacts of engine idling in New York City
Environmental Defense Fund (2/09)

idling fumes

The Big Yellow Asthma Trigger: School bus fumes are especially dangerous for children with asthma
By Lauren Constance Everingham
Advance Respiratory Care Magazine (9/06) Retrofit technology, health effects of biodiesel, the clinician's role.

asthma trigger










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