Legionella Found in Windshield Washer Fluid

Interesting research from Arizona State University found that the bacteria Legionella, commonly found in fresh water, was able to survive in certain automobile windshield washer fluids and can grow in washer fluid reservoirs.  This could potentially lead to people being exposed to the bacteria and maybe developing Legionnaire's disease or Pontiac Fever.

Windshield washer fluid (Photo credit: Wikipedia)

The Arizona State University research was conducted by Otto Schwake, an Arizona State University student pursuing a doctoral degree in Microbiology under the supervision of Morteza Abbaszadegan, a professor in the School of Sustainable Engineering and the Built Environment. Although windshield washer fluid was not normally associated with spreading disease, this research was begun after a series of epidemiological studies found motor vehicle use to be associated with increased risk for Legionnaires' disease.  One such study attributed nearly 20% of Legionnaires' disease cases in the United Kingdom not associated with hospitals or outbreaks to automobile windshield washer fluid.

Based on a recent webinar held by EMLab P&K featuring the Dr. Harriet Burge, Legionella is a gram negative bacterium that is a widely distributed natural inhabitants of water and is common in many environments.  It is heat loving and will proliferate in temperatures between 20 degrees Celsius to 45 degrees Celsius.  Growth is promoted by other micro organisms.  Legionella is the causative agent of Legionellosis (Legionnaires' disease and Pontiac fever).

The first recognized outbreak of Legionnaires disease occurred in Philadelphia in 1976.  As many as 221 people were treated and 34 deaths occurred.  The source was identified as the Legionella bacterium and found in the cooling tower of the hotel's air conditioning system.  Over 90% of legionelloses are caused by Legionella pneumophila.

English: A silver stain of Legionella pneumophila , the bacteria that causes Legionellosis. Although I got this image from a commercial website it is clearly labeled as from the CDC. This website routinely uses images from Wikipedia, which is a good thing, so no issue should be taken with using an presumably public domain image from their website. (Photo credit: Wikipedia)

Legionellosis takes two distinct forms:

• Pontiac Fever: respiratory illness without pneumonia, symptoms resemble acute influenza

• Legionnaires' Disease: symptoms include fever, chills, cough, muscle achees, headache, tiredness, loss of appetite, loss of coordination (ataxia), and occasionally diarrhea & vomiting.

Legionellosis incubates in 2-10 days.  It is one of the top three causes of community-acquired pneumonia. Legionellosis affect 8,000 to 18,000 people in the United States each year. Transmission is not person to person. Legionellosis infection occurs after inhaling droplets that originated from a water source contaminated with Legionella. Environmental sources include freshwater ponds, rivers and creeks.  Typical manmade water sources that can be a source of Legionella include: cooling towers, evaporative coolers, hot water systems, showers, whirlpool spas, architectural fountains, room-air humidifiers, ice-making machines, and misting equipment.  Based on the above research now windshield washer fluid reservoirs, may be added to this list.

Related Articles:

• How To Detect And Identify Legionella
• Portugal: Legionnaires' Disease Alert
• Legionnaires' blamed for chef's death
• Possible Outbreak Of Legionellosis At The Playboy Mansion?

NYC Department of Health Revises Mold Guidelines

New York City Department of Health and Mental Hygiene (NYC DOHMH) has updated their "Guidelines on Assessment and Remediation of Fungi in Indoor Environments". This document supersedes all prior editions of the guidelines. The document was prepared by the Environmental and Occupational Disease Epidemiology Unit of NYC DOHMH. This update includes discussions on visual inspections, environmental sampling, moisture control & building repair, worker training, cleaning methods, quality assurance indicators, restoring treated spaces and the usual remediation procedures. In addition, the update includes a fact sheet for Building Owners & Managers. Click on the title to link up with the NYC website that has this document.

How many clearance samples should be taken for mold remediation?

In a recent article written by Dr. Harriet Burge, in The Environmental Reporter for EMLAB P&K, she discussed this question and came up with an interesting answer. As we discuss in our mold remediation classes, clearance sampling is used to document that the mold contamination was successfully removed as part of a well designed written protocol (scope of work).

In preparing the scope of work for the project, the consultant should take pre-abatement air samples to have a picture of the air before the remediation. Air samples should be taken inside the area being remediated, outside the area being remediated, and outside the building. This sampling must be representative of the air in the areas sampled. Using these results and the data created, the consultant (writing the remediation protocols) can pre-determine the percentage change they want to see in the clearance samples and add that information to the protocols.

Based on Dr. Burge's article she suggests that the number of air samples should represent 5% of the air in the room or 2% of the air in the room if the air is thoroughly mixed. (when mixing air the method used should not send so much dust in the air that it will require you to sample for less than 10 minutes). Assuming a 10 minute air-o-cell sample represents slightly more than five (5) cubic feet of air, a 1000 cubic foot room would require four (4) samples to achieve 2% with proper mixing and ten (10) samples without mixing.

It is important to remember no single sample is representative of any environment (as discussed in Dr.Burge's article and supported by various publications by the American Conference of Governmental Industrial Hygienists (ACGIH), the American Industrial Hygiene Association (AIHA), and others). As consultants, we must ensure the remediations we recommend are complete and this can only be accomplished if the interpetations are supported by quality data that is representative of the environment we are sampling. Multiple samples are the only way to ensure the environment is accurately evaluated.