Healthy Indoors Magazine - USA Edition

Healthy Indoors | 17 system response) has resulted in continued progress in the devel- opment of allergen testing processes. One of the most successful of the new allergen testing processes is AirAnswers. That success with allergen identification led to the efforts to expand the tech- nology to assist with the identification of mold problems as well. Sampling System The AirAnswers sampling system and evaluation process is a novel product originally developed by Inspirotec to identify allergens in indoor air. The technology incorporated into Inspirotec' s AirAn- swers monitoring device has been shown to effectively capture airborne bio-particulates related to allergens, fungi, molds, and pathogens, using sampling times ranging from 1 to 5 days. In contrast to most particulate sampling systems where the contaminants are captured on a filter media or sticky surface, the AirAnswers utilizes an electrokinetic particle capture process. This innovation leads to the collection of more overall particulate than traditional filter or adhesive-based sampling systems, with the added benefit of the capture of much smaller particulates as compared to other sampling systems. Specifically, the AirAnswers system generates air flow over and around a sample cartridge consisting of two electrolyzed stainless-steel prongs, which serve as the system's collection point for airborne particulate. The collected sample cartridges are re-packaged in their initial protective case and submitted to the company's labo- ratory for analysis. The Inspirotec analysis process allows the collected samples to be analyzed using molecular biological techniques such as enzyme-linked-immunosorbent assays (ELISA), a method used for the identification of proteins, and quantitative polymerase chain reaction (qPCR), a technology used for measuring the DNA of living organisms. The qPCR process allows for the identification of minute amounts of specific material, down to the level of micrograms per cubic meter of air (pg/M 3 , or 1 trillionth of a gram of material). The development of the AirAnswers system with such low detection levels of organic material was originally designed to assist with the identification of allergens, including dander from animals, dust mite feces, etc. While such testing remains a key market for the AirAnswers device, the apparent use- fulness of the same capture system for fungal material was rapidly recognized. To offer an upgraded sampling process to the mold inspection industry, Inspirotec developed a specific battery of tests designed for cost-effective fungal sampling. System Improvements One of the primary advancements identified by Inspirotec for the mold inspection industry was the ability of the AirAnswers system to capture and quantify beta-glucans. The Inspirotec patented system selectively detects shorter chain beta glucans, which is the category that penetrates most deeply into the respiratory system. All other work has been on the long chain fraction, which requires digestion before it can be assayed by the limulus amoebocyte system. This is a major improvement from a sampling standpoint because beta-glucans are a more general indicator of possible fungal contamination than identifying spores, or even fragments, and is typically indicative of actively growing mold. Beta-glucans are long-chain carbohydrates that are pres- ent in the cell walls of grains, fungi, and bacteria. The chemical signature of beta-glucan from different living organisms is unique, which allows specific identification of the source material where it originates. Since beta-glucans are in the cell walls of fungal spores, hyphae, and every other part of the organism, they can be identified even if the fungal colony has dried out, been disturbed, or been accidentally left behind by inadequate remediation. Several factors set the AirAnswers sampling system apart from the current indoor air quality industry standard of spore trap sampling. By utilizing an electrokinetic collection method, the captured particulate and bioaerosols are not enmeshed in a suspending compound as is the case with adhesive collection systems. Additionally, the use of the electrokinetic method allows for the capture of ultrafine particles down to at least 0.1 mi- crons, a particle size that can penetrate deeply into the human lung. Another advantage to the AirAnswers system is that the captured sample material is not trapped amid filter fibers, as they will be when using mechanical filtration to collect samples. The smooth surface of the collection electrode allows for all the sample material to be easily collected for subsequent analysis. Moreover, while the sample collection electrodes could theo- retically load to the point where no more particulates will be collected, because the AirAnswers system does not use optical/ visual methods to detect and identify molds, it is not affected by the material overload that degrades and interferes with adhesive capture-based approaches (e.g., spore trap). Finally, while some of the collected bioaerosol material may break up during the process of collection, the utilization of genetic sequencing as the primary identification method by the Inspirotec laboratory to analyze the sample results means that even fungal spore husks or sub-spore size pieces that would be missed by a laboratory analyst visually observing a traditional sample will be detected and included in the quantified results by the AirAnswers process. Another potential benefit to the AirAnswers system is the capability of the Inspirotec laboratory to run multiple types of tests from a single sample "on demand." Since so much sample material is collected by the AirAnswers device, the laborato- ry can divide the sample cartridge into multiple sections that can each be accessed at separate dates. This means that a sample can be sent in to be analyzed on a first pass for gen- eral allergens. Then, if a fungal problem is identified from the AirAnswers data or additional site inspections, the laboratory can subsequently be contacted to run a specific fungal scree- nor mycotoxin test on the same sample cartridge. This allows for significant flexibility to develop a more complete picture of

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