 |
|
Other Indoor Air Quality Issues |
|
|
|
|
|
|
|
|
|||||||||||||||||
|
While it is nearly impossible to eliminate all indoor VOC's the State of Vermont's Department of Health offers these suggestions
for reducing exposure. Source: Vermont
Department of Health, The EPA has a lot of information about VOC's and other indoor air quality issues:
Legionella are small gram-negative
rodshaped bacteria. Over 40 individual species of Legionella are known. The majority of human infections are caused by the species Legionella pneumophila. Legionella pneumophila was first discovered following
a pneumonia outbreak at the 1976 Convention of the American Legion in Philadelphia. The species Legionella pneumophila is divided into sixteen subgroups (called serogroups). HEALTH EFFECTS IN HUMANS There are two
forms of Legionellosis, pontiac fever and the more severe Legionnarires’ Disease. Pontiac Fever: Pontiac fever is a less severe
form of Legionellosis which is charaterized by flu-like symptoms (fever, chills, headache, and muscle pain) lasting 2-5 days. Legionnaires’ Disease: Legionnaires’ disease is a potentially fatal illness involving pneumonia. Early symptoms include musclepain,
loss of appetite, headache, high fever, dry cough, chills, confusion, disorientation, nausea, diarrhea, and vomiting.
Later symptoms include chest pain and difficulty breathing. It is difficult to distinguish this disease from other pneumonias.
Early diagnosis and treatment are extremely important. Treatment consists of intravenous administration of antibiotics. HEALTH EFFECTS IN ANIMALS There are no reports of naturally infected animals. Scientists may
artificially infect experimental animals (such as guinea pigs and gerbils) with Legionella to study disease. ENVIRONMENTAL PROFILE Ecology: Legionella are mostcommonly found in water, including groundwater,
fresh and marine surface waters, and potable (treated) water. Legionella are protected againist standard water
disinfection techniques, by their symbiotic relations with later microorganisms. Occurrence: Legionella are relatively resistant to standard water disinfection procedures and, can occur in potable water. These
bacteria have been found in water distribution systems of hospitals, hotels, clubs, public buildings, homes, and factories.
Other waters in which Legionella have been found
include cooling towers, evaporative condensers and whirlpools. These bacteria may be transported from potable water
to air by faucets, showerheads, cooling towers, and nebulizers. Transmission
to Humans: Legionella are
transmitted directly from the environment to humans. There is no evidence of human-to- human or animal-to-human transmission
of these bacteria. Potable water is the most important source of Legionella. Humans may inhale contaminated aerosols or aspirate small amounts of contaminated drinking water.
No vaccine is available to prevent infection. Outbreaks: Cases of legionellosis (any disease caused
by Legionella) have been
reported in North and South America, Asia, Australia, New Zealand, Europe, and Africa. National surveillance programs
areconducted in the United States, 24 European countries (including England), Australia, and New Zealand. Legionellosis
outbreaks most frequently have been attributed to contaminated potable water, cooling towers, or components of water distribution
systems. Outbreaks in hospitals have been linked to hospital potable water supplies, air conditioning systems, and cooling
towers. Travelers can be exposed to Legionella in
contaminated hotel potable water or contaminated whirlpool spas. Community outbreaks are caused by exposure to a wide variety
of sources, but potable water and cooling towers are the most common. RISK FACTORS The general population (healthy
individuals) is fairly resistant to infection. Certain groups of people are at increased risk for contracting legionnaires’
disease, including: hospital patients who require intubation, have received ventilation assistance, or are receiving respiratory
therapy people taking corticosteroids or other immunosuppressive drugs solid organ transplant patients, especially those requiring
dialysis people with certain chronic health conditions (chronic obstructive pulmonary diease,diabetes, head or neck cancer,
or end-stage kidney disease) heavy smokers or drinkers Legionnaires’ disease in these people may be associated with
more severe illness and increased mortality. ANALYTICAL
METHODS Environmental
samples should be collected by swabbing areas where water flows (such as faucets and shower heads). The specimen should
be concentrated by filtration, treated with an acid buffer to enhance Legionella recovery, and cultured on a selective buffered charcoal yeast extract
(BCYE) agar medium. Culture assays are the most common tests used to detect Legionella
in environmental and biological samples. WATER TREATMENT Control
methods designed to disinfect an entire water distribution system include : thermal
(super heat and flush) ultraviolet light
sterilization Selecting one or a combination of these two types of control methods would be best for eradicating Legionella colonies and preventing
recolonization of the water distribution system. REGULATORY
INFORMATION EPA has established a Maximum Contaminant
Level Goal (MCLG) of zero organisms for drinking water. An MCLG is a non-enforceable guideline based solely on an evaluation
of possible health risks, taking into consideration a margin for public safety. ADDITIONAL HELP •
EPA has established the Safe Drinking Water Hotline, a toll-free number for further information on drinking water quality,
treatment technologies, and for obtaining Health Advisories or other regulatory information. • Safe Drinking Water Hotline: • Your state or county health officials or experts in
your state’s Department of Environmental Protection or Natural Resources may also be of assistance |
||||||||||||||||
|
|||||||||||||||||
|
|
|
|
||||||||||||||
|
|||||||||||||||||
|
|
||||||||||||||||||||||||||
