RACHEL's Hazardous Waste News #120

=======================Electronic Edition========================

One reason why people often oppose a new facility is increased
truck traffic. Trucks are big and noisy and subject to accidents,
and when accidents occur involving trucks, there’s a high
likelihood of fatalities.

However, the federal government has recently concluded officially
that there is another good reason to be concerned about increased
truck traffic in your neighborhood: five separate studies in the
last 3 years have shown that diesel exhaust certainly causes
cancer in laboratory animals, and two studies of railroad workers
show that it causes cancer in humans as well. As a result of this
determination, the National Institute for Occupational Safety and
Health (NIOSH) has issued a special publication, CARCINOGENIC
EFFECTS OF EXPOSURE TO DIESEL EXHAUST, offering this
recommendation: “As prudent public health policy, employers
should assess the conditions under which workers may be exposed
to diesel exhaust and reduce exposures to the lowest feasible
limits.” Citizens may reasonably ask: if NIOSH believes workers
should not be exposed to diesel exhaust because of the cancer
hazard, can health officials in other parts of government believe
that the general public should continue to be exposed to diesel
exhaust? Taken in this light, risk assessments that discuss only
the traffic hazards associated with a facility are missing the
major point: diesel trucks can evidently kill innocent people
even if no traffic accidents occur.

Diesel engines are more efficient than gasoline engines; they
produce more horsepower per gallon of fuel, and they use a
less-refined (thus cheaper and more plentiful) fuel. When diesel
fuel burns in an engine’s combustion chamber, the resulting
exhaust contains gases and particles (soot). The gases include
nitric oxide, nitrogen dioxide, oxides of sulfur, and
hydrocarbons (e.g., ethylene, formaldehyde, methane, benzene,
phenol, 1,3butadiene, acrolein, and polynuclear aromatic
hydrocarbons [PAHs], several of which are known carcinogens). Of
the particles in diesel exhaust, 95% are less than 1 micron in
diameter and thus they are respirable, which is to say they are
easily taken into the deepest portions of the human lung where
they may lodge forever. The core of each particle is made up of
pure carbon, but as many as 18,000 different chemicals from the
gaseous portion of the exhaust may be adsorbed (attached) onto
the carbon core, and thus diesel exhaust can carry a whole host
of exotic, toxic and carcinogenic chemicals into the deepest
portions of your lung-down in the region where the transfer of
gas occurs to put oxygen into your blood stream and to take
carbon dioxide out.

As recently as 1986, NIOSH concluded that diesel exhaust did not
cause cancer in laboratory animals. However, in the period
1986-1988, five long-term animal studies, and two epidemiologic
studies of humans, all concluded that exposure to diesel exhaust
causes lung cancer. As a result, NIOSH reversed itself and in
August, 1988, issued a special “current intelligence bulletin” to
get the word out that diesel fumes are dangerous. NIOSH estimates
that 1.35 million American workers are routinely exposed to
diesel exhausts.

Get: CARCINOGENIC EFFECTS OF EXPOSURE TO DIESEL EXHAUST [CURRENT
INTELLIGENCE BULLETIN 50; DHHS (NIOSH) PUBLICATION NO. 88-116].
Cincinnati, OH: Division of Standards Development and Technology
Transfer, NIOSH, Robert A. Taft Laboratories [4676 Columbia
Parkway, Cincinnati, OH 45226], August, 1988; phone (513)
5338287. It’s 30 pages and free.
–Peter Montague, Ph.D.

Descriptor terms: particles; nox; nitric oxide, nitrogen
dioxide, oxides of sulfur, hydrocarbons (ethylene, formaldehyde,
methane, benzene, phenol, 1,3butadiene, acrolein, and polynuclear
aromatic hydrocarbons [PAHs]); diesel; air pollution; trucks;
transportation; studies; warnings; occupational safety and
health; cancer; health effects;

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