The worm turns for IAQ sensing?

Researchers at the University of Turku in Finland have developed a new method for measuring indoor air quality, making use of fluorescent nematodes.

The transgenic nematodes used in this study express green fluorescent protein (GFP). Production of GFP is enhanced upon exposure of these millimeter-long nematodes to increasing concentrations of harmful compounds.

Microbial or chemical contaminants in the air can be toxic or irritative and cause allergic reactions, asthma or other diseases in exposed individuals. However, there are currently no widely accepted methods for monitoring the risks associated with exposure to hazardous indoor air agents, so novel approaches are needed.

In a project carried out in the Department of Biology at the University of Turku, researchers are attempting to take advantage of transgenic strains of Caenorhabditis elegans nematodes. These strains produce green fluorescent protein (GFP) when forced to smell or taste harmful biological or chemical impurities. The extent of this fluorescence can be measured by spectrometry.

Such nematodes have previously been used to monitor the biological effects of heavy metals and other environmental agents,” explained project leader Päivi Koskinen. “When we exposed nematodes to fungal samples collected from moisture-damaged buildings, we indeed observed significantly increased amounts of fluorescence,” continues Koskinen.

The researchers observed that with the new method, it is also possible to detect other impurities in the indoor air, such as surfactants used in cleaning products or volatile compounds produced by phtalates (softeners of plastic carpets) degrading under moist conditions.

“The nematodes cannot tell us what kind of toxic compounds there are in the air, but they can provide an unbiased opinion on health risks associated with indoor air and on the need for more thorough technical investigations,” said Koskinen.