Wednesday, June 10, 2015

Mold in the Richmond Veterans Hospital

According to the Institute of Medicine of the Center for Disease Control and Prevention (CDC) there is sufficient evidence to link indoor exposure to mold with upper respiratory tract symptoms, cough, and wheeze in otherwise healthy people; with asthma symptoms in people with asthma; and with hypersensitivity pneumonitis in people with stressed or compromised immune systems. In addition there is evidence linking indoor mold exposure and respiratory illness. While molds are present at low levels in air, a mold problem in any building can be unpleasant or even sickening to the occupants, but as will be shown below, exposing hospital patients to a “moldy” environment can increase the risk of infection in some patients and therefore requires rigorous remediation.

Last March the McGuire Veterans Administration Medical Center in Richmond, Virginia hired an environmental consulting firm to perform an Indoor Air Quality Assessment in response to complaints from employees and patients about perceive poor indoor air quality and a recommendation from an outside group. The consultants performed a visual assessment of wards 1U, 1V and 1W and the Nurses Stations, checked the filters in the HVAC systems and made sure that the HVAC systems appeared to be clean. They also recorded the Temperature, Relative Humidity, Carbon Monoxide and Carbon Dioxide and used the test device called Micro 5 five minute low volume spore traps to collect 14 interior hallway samples and one exterior sample to measure total airborne fungal spore levels at a particular point in time in an attempt to identify if the hospital had a mold problem that might be impacting the employees and patients.

Currently, there are no federal standards (OSHA, NIOSH, EPA or CDC) for airborne concentrations of mold or mold spores.There are however OSHA , EPA and CDC guidlines for mold remediation wich implicity acknowledges the seriousness of mold contamination. Scientific research on the relationship between mold exposures and health effects continues, but there are yet to be determined absolute levels of exposure that are of no concern and threshold numeric levels likely to impact exposed populations. Molds are part of the natural environment. Molds are fungi that can be found anywhere - inside or outside all year long. About 1,000 species of mold can be found in the United States, with more than 100,000 known species worldwide. In recent years indoor air quality experts, the World Health Organization (WHO), Industrial hygienists and several scientific groups have developed standard approaches to investigating mold problems. Spore traps have become the dominant way of airborne mold sampling, but only test for a handful of spore species that most commonly indicate a problem.

There have been recent papers, presentations, and scientific articles that address whether an interior space is “moldy.” What emerges from these evaluations is that the most common indicator of mold problems in a damp environment is the elevated presence of two related species in particular Aspergillus/Penicillium. These spores are the primary colonizers according to the World Health Organization (WHO – 2009) and often amplify in the indoor environment in response to increased moisture. In addition, it is well documented in studies funded by the National Institute of Health that elevated concentrations of Aspergillus species of fungus in critical-care areas of hospitals, may result in an increased risk of infection in immuno-compromised patients (Kordbacheh et al. 2005; Lee et al. 2007). The CDC states that “the types of health problems caused by Aspergillus include allergic reactions, lung infections, and infections in other organs.” Thus, in the chart below and the discussion that follows, I only examine Aspergillus/Penicillium and total spore count in the 15 samples taken to determine if the sampling results are indicative of a mold problem at the McGuire VA Medical Center in Richmond, VA.
When evaluating fungal spore levels there are three basic approaches to determine if the spore levels measured in a spore trap are of concern: comparing the finding to a reference sample, typically outdoor sample is taken, comparing the value to a control sample from similar building(s) that has not been impacted, or comparing the findings against a data base of mold impacted buildings.

When doing a spore trap sampling it is common with residential and small commercial investigations to sample the outdoor air as a reference sample as was done in this instance. However, air residence time in larger buildings can be hours or several days depending on the size of the building and air flow circulation and whether air filtration systems are operating. In modern buildings with active mechanical ventilation systems the indoor concentration of airborne spore is generally expected to be between 20-70% of the outdoor concentration with an assumed average of 50%. It is important to note that the comparison should be the relative concentration of each spore type and not just the total spore concentration (Spurgeon, 2004). As you can see in the chart above only one sample location (1W-103) had an Aspergillus/Penicillium spore count within the expected range compared to the exterior, all of the other samples were 100% to 2,950%. For the total spore count only the samples with the highest levels of Aspergillus/Penicillium (1U-141 and 1U-138) exceeded the expected range. By comparison to an exterior (reference) sample elevated levels of Aspergillus/Penicillium spores are of concern.

In large commercial complexes control samples can often be obtained from unimpacted buildings or unimpacted wings of buildings. Though the total spore count in most of the samples is significantly below the exterior sample, the elevated levels of Aspergillus/Penicillium and two samples showing elevated total spore levels indicate that there are areas within the building that are more impacted by fungal spores than others. The data indicates a hot spot that is more significantly impacted than other areas, though elevated levels of Aspergillus/Penicillium are ubiquitous. These hot spots should be more fully delineated. Remediation of the area should take place after identifying and eliminating the sources of moisture.

The final method of evaluating fungal spore data is by comparing the samples taken to a database of sampling results for buildings that have been tested. The concentration of airborne contaminants can be characterized by a lognormal distribution with a geometric mean concentration and standard deviation. Joe Spurgeon, PhD, CIH performed an analysis on the data from three studies to find the Aspergillus/Penicillium level for a “moldy” environment. Dr. Spurgeon created the table below from three separate groups of data:

Aspergillus/Penicillium levels considered as indicative of a “moldy” environment from three independent studies:

1. Baxter data: Asp/Pen ≥ 950 spores/m3
2. Rimkus data: Asp/Pen ≥1,000 spores/m3
3. Spurgeon data: Asp/Pen ≥ 1,000‐1,100 spores/m3

The sample from 1U-141 location would be classified by this database comparative approach as a moldy environment. In addition, that sample was in the 95-99 percentile for Aspergillus/Penicillium compared to all building samples represented in the database. Clearly the extent and source of the Aspergillus/Penicillium fungal spores needs to be identified, isolated and remediated.

In all methods of evaluation, the levels of Aspergillus/Penicillium identified at the McGuire VA Medical Center indicate a localized but significant mold problem that might impact the health of patients and staff. Additional tests should be performed to delineate the extent of the problem. The area of impact should be remediated following U.S. EPA and the CDC guidelines and confirmation testing performed. It is my understanding that the on-site Administrator has chosen to take no action, but this could potentially impact the health and comfort of the staff and our most vulnerable patients.

While there are currently no  federal regulations setting a threshold level for mold concentrations that would require remediation, available research shows that such a level is already and increasingly knowable. It is only a matter of time until such knowledge is embodied in a regulation and it is better to act now on what we already now then to risk harm while awaiting regulation to force action. We have established the Veterans Administration hospital system especially for veterans due to their extraordinary service to our county and a problem like this which puts their heath at further risk should not be ignored. In Pittsburgh, PA hospital patients died of mold infections. 

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