Systems for measuring pollution use passive sensors which measure the levels of some pollutants. The risks to public health are then deducted based on known interactions between each pollutant and the human body. Researchers at the University of Metz offer a complementary approach, which is to measure the real impact of pollution on a culture of lung cells, without seeking to establish the exact composition of the air.
The idea of the Laboratoire de Microbiologie Immunologie de l’IUT de Metz, Département Génie Biologique (Laboratory of Microbiology Immunology of the IUT of Metz, Department of Bioengineering) is somehow inspired the “mouse test” imposed to the oyster farmers (if the mouse dies, the sale is prohibited). Instead of measuring the amount of some isolated compounds by using physico-chemical sensors, this is to observe the impact of an air sample on human cells, without counting all pollutants or even understand the interactions between them.
Cleaning cells slow down
If the idea is simple, the machine is patented by LECES Environnement, the industrial partner of the research team, is frankly much more sophisticated. First, monocytes and macrophages to defend the human respiratory system shall be produced. Usually, these phagocytes roam freely on the surface of alveoli to swallow the particles, microorganisms and other contaminants which have not been filtered by the upper respiratory system (nose, bronchus …). The machine, which is nicely named “Environmental Biosensor of Metrology of Air Contaminants” contains a bioreactor, ie, culture medium, which temperature, pH, dissolved oxygen and the amount of cells are regulated.
Some macrophages are then automatically placed on an “exposure chamber” and subjected to an “stimulating agent” that pushes them to move. A bit like a snail race attracted a lettuce leaf. Here comes the air. A first race of ten minutes is organized in clean air to measure the speed of macrophages with via a camera under a laser light. Then comes the second round in the sampled air, this time. Yet, it is known from previous studies that the macrophages are much slower when operating in polluted air. Finally, the speed difference between the two races gives a real and accurate indicator of the level of pollution by air contaminants in the studied air. QED.
A difficult marketing
The price of the device should be in the same price range as the classic physico-chemical sensors, to which he can’t be substituted either. “The biosensor responds to a global cocktail but does not say what the pollutants are. But we must have this information to take corrective action. It is therefore a complementary tool, “says Dr. Philippe LAVAL-GILLY, a researcher who worked on the project.
In the meantime, the marketing is longer than expected. And for a good reason because there is no certifying organization approved to validate the biosensor. The device must indeed demonstrate its reliability in time by multi-site test protocols before obtaining the authorization to be sold. This does not worry the lab of the IUT of Metz, who thinks to other applications on the same principle, eg. the measurement of water quality.