Feb. 5, 2004
The region’s clean
air agency started an intensive one-year study this week to assess current
levels of cancer-causing toxic air pollutants and the risk they pose to
Southland residents.
“Since our last toxic air pollution study six years ago, we have
reduced cancer-causing emissions through numerous regulations,” said Barry
Wallerstein, executive officer of the South Coast Air Quality Management
District.
“This study will help us gauge the effectiveness of our current
regulations and serve as a vital tool in helping shape future air quality
and environmental justice policies.”
AQMD this week started collecting air samples for some substances in
the Multiple Air Toxics Exposure Study III (MATES III). Sampling for all
substances is expected to begin in mid-February. This year’s study
follows the landmark MATES II, conducted in 1998-1999, and the seminal
MATES, run in 1986-1987.
The goal of MATES III is to update toxic air pollution levels and toxic
emission inventories, and then input those data into a computer model of
air dispersion to determine the cancer, as well as non-cancer, health risk
from air toxics across the Southland. The study also will investigate
potential toxic “hot spots” in communities.
MATES III will monitor for 21 toxic air contaminants and four other
substances at 10 sites across the Los Angeles Basin (see lists below). In
addition, starting next month, AQMD will use moveable monitoring stations
to sample at a dozen or more neighborhood sites near toxic emission
sources or in areas where community members are concerned about health
risks from air pollution. Such neighborhood sites could be near airports,
railroads, warehouses, landfills, high-volume vehicle traffic or multiple
commercial or industrial facilities. Sampling at each neighborhood site
will last for up to two months.
During MATES III, AQMD will double the monitoring frequency of the
previous study from one-in-six days to one-in-three. In addition to the
most significant pollutants sampled in MATES II, the current study will
include limited sampling for naphthalene, a combustion byproduct that may
pose a significant health hazard, according to current assessments by
environmental agencies and academic researchers.
AQMD scientists have convened a technical advisory group, including
representatives of other environmental agencies, universities, industry
and environmental groups. The committee will help guide the study from
start to finish and will assist in selecting the specific neighborhood
monitoring sites.
Monitoring will continue through early 2005. The study is expected to
be finished during summer 2005.
Since the completion of MATES II, AQMD’s Governing Board has placed a
high priority on reducing toxic air pollution and resulting health risk.
In 2000 and 2001, the Board adopted a series of clean fleet rules to
reduce diesel exhaust from transit buses, trash trucks, street sweepers,
airport taxis, school buses and other fleets. Diesel engine manufacturers
and oil companies have challenged the regulations in the Supreme Court of
the United States. The court is expected to issue an opinion in the case
this spring.
AQMD’s Board also has adopted regulations to reduce perchloroethylene
from dry cleaners and other industries, and hexavalent chromium from metal
plating facilities. In addition, the Board has approved more than $100
million in local and state funding to help replace aging, dirty diesel
engines in school buses, marine vessels and other vehicles with
lower-emission diesel and alternative fuel models.
MATES II, the nation’s most comprehensive study of toxic air pollution
to date, found that:
- Diesel exhaust is responsible for about 70 percent of the total
cancer risk from air pollution;
- Emissions from mobile sources -- including cars and trucks as well
as ships, trains and planes -- account for about 90 percent of the
cancer risk. Emissions from businesses and industry are responsible for
the remaining 10 percent; and
- The highest cancer risk occurs in south Los Angeles County --
including the port area-- and along major freeways.
AQMD is the air pollution control agency for Orange County and major
portions of Los Angeles, San Bernardino and Riverside counties.
