Fijne stofdeeltjes verantwoordelijk voor hart- en ademhalingsproblemen.*
Uit een 4 jarige studie onder de gegevens van 11,5 miljoen Amerikanen blijkt dat de hoeveelheid fijnstof in de lucht evenredig is met de kans op problemen met het hart en de ademhalingsorganen. Bij mensen van 75 jaar en ouder is de kans echter nog groter. De gemiddelde hoeveelheid gemeten fijnstof was 13,4 microgram per kubieke meter lucht.
Iedere 10 microgram meer geeft 1,28% meer ziekenhuis opnames.
Pollution
Significantly Increases The Risk For Cardiovascular, Respiratory Disease In
Elderly
New data from a four-year study of
11.5 million Medicare enrollees show that short-term exposure to fine
particle air pollution from such sources as motor vehicle exhaust and power
plant emissions significantly increases the risk for cardiovascular and
respiratory disease among people over 65 years of age. The study, funded by
the National Institute of Environmental Health Sciences, a component of the
National Institutes of Health, is the largest ever conducted on the link
between fine particle air pollution and hospital admissions for heart- and
lung-related illnesses.
The study results show that small increases in fine particle air pollution
resulted in increased hospital admissions for heart and vascular disease, heart
failure, chronic obstructive pulmonary
disease, and respiratory infection. "The data show that study
participants over 75 years of age experienced even greater increases in
admissions for heart problems and chronic obstructive pulmonary disease than
those between 65 and 74 years of age," said National Institutes of
Health Director Elias A. Zerhouni, M.D.
The National Institute of Environmental Health Sciences and the U.S.
Environmental Protection Agency provided funding to researchers at the Johns
Hopkins Bloomberg School of Public Health for the study. The study results
are published in the 2006 issue of the Journal of the American Medical
Association.
According to the study, these findings document an ongoing threat from
airborne particles to the health of the elderly, and provide a strong
rationale for setting a national air quality standard that is as protective
of their health as possible.
"These findings provide compelling evidence that fine particle
concentrations well below the national standard are harmful to the
cardiovascular and respiratory health of our elderly citizens," said
NIEHS Director David A. Schwartz, M.D. "Now that the link between
inhaled particles and adverse health effects has been established, we must
focus our efforts on understanding why these particles are harmful, and how
these effects can be prevented."
Fine particle air pollution consists of microscopic particles of dust and
soot less than 2.5 microns in diameter - about thirty times smaller than the
width of a human hair. These tiny particles primarily come from motor
vehicle exhaust, power plant emissions, and other operations that involve
the burning of fossil fuels. Fine particles can travel deep into the
respiratory tract, reducing lung function and worsening conditions such as asthma and bronchitis.
The researchers based their fine particle analysis on 11.5 million Medicare
enrollees who lived in 204 U.S. counties with populations larger than
200,000. Using billing records for 1999 to 2002, they tracked daily counts
of hospital admissions for eight major outcomes - heart failure, heart
rhythm disturbances, cerebrovascular events such as stroke or brain hemorrhage, coronary heart disease,
peripheral vascular disease or narrowing of the blood vessels, chronic
obstructive pulmonary disease, respiratory infection, and injury.
The investigators obtained daily measurements of fine particle
concentrations from a network of air monitoring stations provided by the
Environmental Protection Agency's Aerometric Information Retrieval Service.
The average fine particle concentration for the 204 counties over the
three-year period was 13.4 micrograms per cubic meter of air, slightly below
the national air quality standard of 15 micrograms per cubic meter for an
annual average.
"When we analyzed the data for heart failure, we observed a 1.28
percent increase in admissions for each 10 microgram per cubic meter
increase in fine particle pollution," said Francesca Dominici, Ph.D.,
an associate professor of biostatistics with the Johns Hopkins Bloomberg
School of Public Health and lead author on the study. "Most of these
admissions increases occurred the same day as the rise in fine particle
concentration, which suggests a short lag time between the change in
pollution and the subjects' response."
The data also showed that the risk for air pollution-related cardiovascular
disease was highest in counties located in the Eastern United States. "Identifying
the various factors that might contribute to these differences between
eastern and western regions is a very complex question that we must address,"
said Dominici.
According to Dominici, fine particles pose a significant health problem
because they penetrate deep into the lungs, and some may even get into the
bloodstream. "Now that we know that inhaled particles can affect
cardiovascular and respiratory health, we must identify the specific
characteristics of fine particles that produce these adverse health effects,"
she said. "In the meantime, these findings underscore the need for a
national air quality standard that adequately protects the respiratory
health of our citizens."
###
NIEHS, a component of the National Institutes of Health, supports research
to understand the effects of the environment on human health. For more
information on fine particle air pollution and other environmental health
topics, please visit the NIEHS website at http://www.niehs.nih.gov/home.htm.
Reference: F. Dominici, D. Peng, M. Bell, L. Pham, A. McDermott, S.L. Zeger,
J.M. Samet. Fine Particulate Air Pollution and Hospital Admissions for
Cardiovascular and Respiratory Diseases. Journal of American Medical
Association 295, 2006.
Contact: John Peterson
peterso4@niehs.nih.gov
NIH/National Institute of Environmental Health Sciences
(
april 2006)