Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Endotoxins in house dust pose a significant risk for asthma

02.12.2005


Exposure to household endotoxin levels poses a significant risk for asthma, according to the first nationwide sampling of house dust.



The study appears in the first issue for December 2005 of the American Journal of Respiratory and Critical Care Medicine, published by the American Thoracic Society.

Endotoxins are toxic substances associated with the outer membrane of certain gram-negative bacteria. These molecules are bound to the bacterial cell wall and are released when the bacterium ruptures or disintegrates. According to the authors, inhalation exposure to endotoxins is common in homes. Indoor sources include: dust, pets, humidifiers, pests, and outdoor air.


Past studies have shown that exposure can cause lung inflammation.

Peter S. Thorne, Ph.D., of the Environmental Health Sciences Research Center at the University of Iowa, Iowa City, and five associates, evaluated 2,456 residents in 831 homes selected to represent the demographic characteristics of the U.S. population. The investigators took 2,552 house dust samples from five locations within the homes, including bedroom floors, bedding, family room floors, sofa surfaces, and kitchen floors.

"This study clearly demonstrates significant relationships between household endotoxin and diagnosed asthma, recent asthma symptoms, current use of asthma medications, and wheezing," said Dr. Thorne. "No effect was observed of allergy status on the relationship between endotoxin and asthma outcomes. This suggests that current endotoxin exposure may have little impact on allergy status and that airway inflammation is the most significant effect of endotoxin exposure in a cross-section of the population."

The authors found the strongest relationship between asthma, asthma medications, and wheezing came from endotoxin levels in bedroom floor and bedding dust. However, the effects were observed only in adults and not in children.

Moreover, the investigators also noted that the endotoxin concentrations were highest in kitchen and living room floor dust, and lowest for bedding (including mattress and pillow).

"The mean concentration of endotoxin in the kitchen floor dust was 2.3-fold higher than bedroom floor dust and 4.3-fold higher than bedding dust," said Dr. Thorne.

Two field workers visited each household and took answers from residents to detailed questionnaires, conducted a home inspection, and vacuumed dust into an in-line filter.

The study yielded an 11.3 percent prevalence rate for diagnosed asthma among the homes surveyed. This figure compared favorably with the 11.1 percent prevalence rate of diagnosed asthma associated with the 2002 National Health Interview Survey.

The authors also noted that their national survey demonstrated that U.S. household endotoxin exposure levels were higher than those in Europe.

Suzy Martin | EurekAlert!
Further information:
http://www.thoracic.org

More articles from Health and Medicine:

nachricht Study suggests possible new target for treating and preventing Alzheimer's
02.12.2016 | Oregon Health & Science University

nachricht The first analysis of Ewing's sarcoma methyloma opens doors to new treatments
01.12.2016 | IDIBELL-Bellvitge Biomedical Research Institute

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

Im Focus: Molecules change shape when wet

Broadband rotational spectroscopy unravels structural reshaping of isolated molecules in the gas phase to accommodate water

In two recent publications in the Journal of Chemical Physics and in the Journal of Physical Chemistry Letters, researchers around Melanie Schnell from the Max...

Im Focus: Fraunhofer ISE Develops Highly Compact, High Frequency DC/DC Converter for Aviation

The efficiency of power electronic systems is not solely dependent on electrical efficiency but also on weight, for example, in mobile systems. When the weight of relevant components and devices in airplanes, for instance, is reduced, fuel savings can be achieved and correspondingly greenhouse gas emissions decreased. New materials and components based on gallium nitride (GaN) can help to reduce weight and increase the efficiency. With these new materials, power electronic switches can be operated at higher switching frequency, resulting in higher power density and lower material costs.

Researchers at the Fraunhofer Institute for Solar Energy Systems ISE together with partners have investigated how these materials can be used to make power...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

UTSA study describes new minimally invasive device to treat cancer and other illnesses

02.12.2016 | Medical Engineering

Plasma-zapping process could yield trans fat-free soybean oil product

02.12.2016 | Agricultural and Forestry Science

What do Netflix, Google and planetary systems have in common?

02.12.2016 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>