Thursday, August 04, 2005

EPA Fine Particles - Buckle on your Chin Strap

News for Release: Friday, July 1, 2005
U.S. Environmental Protection Agency (EPA)
Final EPA Staff Paper Recommends Stronger Particle Pollution Standards

A big shoe dropped early in July, and few heard it fall. EPA released a staff draft document on particle pollution. OSHAniks will not recognize this in procedure, it's like publishing as a pre-preamble, for comment, the recommendation by OSHA staff to the Assistant Secretary. Apparently EPA is under court order to issue a proposal for particulate limits by December 2005 and a final rule by September 2006.

This will be a reengagement of the huge fight of a few years ago, when EPA attempted a small particle standard that was essentially equivalent to the then coarse particle standard.

The staff document, 512 pdf pages, frustrates a reader looking for the beef. As best BrooklynDodger could find, the meat is this.

EPA staff recommend mildly improve limits based on "the evidence of mortality and morbidity effects in areas where the current standards were met." Permitted averages are not much changed, but daily excursions above those averages are likely the targets.

Proposed changes are not very protective, they are actually effect levels for increased mortality.

Stay tuned for the next battle.

Contact: John Millett 202-564-4355 /
(Washington, D.C.-July 1, 2005)

A key document in EPA's review of
national air quality standards for particle pollution recommends the
administrator consider strengthening and refining current standards to
better protect public health and visibility...The Clean Air Act requires EPA to periodically review air quality standards to ensure they provide adequate health and environmental
protection and to update those standards if necessary. In December
2004, EPA and states began implementing the first fine particle standard
when the agency designated areas of the country that require additional
local, state and federal steps to reduce PM 2.5.
... the staff paper concludes
that the latest scientific, health and technical information about
particle pollution supports strengthening EPA's current health-based
standards for fine particles. ...

The staff paper recommends that EPA continue to regulate but revise the
current PM10 standards with a new health-based standard for particles
known as "thoracic coarse" particles -- particles between 2.5 and 10
micrometers in diameter that can be deeply inhaled. Staff recommends
that such a standard apply to more toxic urban coarse particles.
The agency is required by a consent decree to issue a
proposal regarding the particle pollution standards by Dec. 20, 2005,
and to issue a final rule by Sept. 27, 2006.

That rule may, or may not,
include changes to the existing standards.
EPA estimates that meeting existing PM 2.5 standards will prevent at
least:15,000 premature deaths; 75,000 cases of chronic bronchitis;
10,000 hospital admissions for respiratory and cardiovascular disease;
hundreds of thousands of occurrences of aggravated asthma; and 3.1
million days when people miss work because they are suffering from
symptoms related to particle pollution exposure.
The reduction of fine particle pollution is a critical element of the
Administration's comprehensive national clean air strategy. The
strategy includes EPA's recent Clean Diesel Program to reduce pollution
from highway, nonroad and stationary diesel engines, the Clean Air
Interstate Rule to reduce pollution from power plants in the eastern
United States, and the Clean Air Visibility Rule.

To read the final staff paper, a fact sheet, and related materials, go

To read
the CASAC letter to the Administrator regarding the previous draft of
the staff paper, go to:

5.3.7 Summary of Staff Recommendations on Primary PM2.5 NAAQS

Staff recommendations for the Administrator's consideration in making decisions on the
primary PM2.5 standards, together with supporting conclusions from sections 5.3.1 through 5.3.6,
are briefly summarized below...

( 1) Consideration should be given to revising the current PM2.5 primary standards to provide
increased public health protection from the effects of both long- and short-term exposures
to fine particles in the ambient air. This recommendation is based in general on the
evaluation in the CD of the newly available epidemiologic, toxicologic, dosimetric, and
exposure-related evidence, and more specifically on the evidence of mortality and
morbidity effects in areas where the current standards were met,
together with judgments
as to the public health significance of the estimated incidence of effects upon just
attaining the current standards.
( 2) The indicator for fine particle standards should continue to be PM2.5. This
recommendation is based on the conclusion that the available evidence does not provide
a sufficient basis for replacing or supplementing a mass-based fine particle indicator with
an indicator for any specific fine particle component or subset of fine particles, nor does
it provide a basis for excluding any components; on the evaluation in the CD of air
quality within the intermodal particle size range of 1 to 3 µm; and on the policy judgment
made in the last review to place regulatory importance on defining an indicator that
would more completely capture fine particles under all conditions likely to be
encountered across the U.S., while recognizing that some limited intrusion of small
coarse particles will occur in some circumstances. Consideration should be given to
modifying the FRM for PM2.5 based on instrumentation and operational improvements
that have been made since the PM2.5 monitoring network was deployed in 1999, and to
the adoption of FEMs for appropriate continuous measurement methods.
( 3) Averaging times for PM2.5 standards should continue to include annual and 24-hour
averages to protect against health effects associated with short-term (hours to days) and
long-term (seasons to years) exposure periods. Consideration of other averaging times,
especially on the order of one or more hours, was limited by a lack of adequate
information at this time.
( a) Consideration should be given to revising the form of the annual standard to one
based on the highest community-oriented monitor in an area or, alternatively, to
one with more constrained requirements for the use of spatial averaging across
community-oriented monitors.
( b) Consideration should be given to revising the form of the 24-hour standard to a
99th percentile form or, alternatively, to retaining the 98th percentile form, based in
part on considering the degree of risk reduction likely to result from the
combination of the form and the level of a standard.
( 4) Consideration should be given to alternative suites of PM2.5 standards to provide
protection against effects associated with both long- and short-term exposures, taking
into account both evidence-based and risk-based considerations. Integrated
recommendations on ranges of alternative suites of standards that, when considered
together, protect against effects associated with both long- and short-term exposures
( a) Staff recommends consideration of an annual PM2.5 standard at the current level
of 15 µg/m3 together with a revised 24-hour PM2.5 standard in the range of 35 to
25 µg/m3, based a 98th percentile form for a standard set at the middle to lower
end of this range, or a 99th percentile form for a standard set at the middle to upper
end of this range.
Staff judges that such a suite of standards could provide an
appropriate degree of protection against serious mortality and morbidity effects
associated with long- and short-term exposures to fine particles.
( b) Alternatively, staff also recommends consideration of a revised annual PM2.5
standard, within the range of 14 to 12 µg/m3, together with a revised 24-hour
PM2.5 standard in the range of 30 to 40 µg/m3.

No comments: