Vinyl chloride (VC) is a cancer-causing compound formed from
solvents in ground water systems under anaerobic conditions. These solvents are
used in many industrial applications around the world, and often belong to the
most encountered ground water pollutants in industrialized countries. As ground
water is a major drinking water resource, researchers sought to determine if
vinyl chloride can be further degraded into harmless compounds.
A group of scientists at Ecole Polytechnique Fédérale de
Lausannne (EPFL) and the University of
Neuchâtel, Switzerland, has studied the
degradation of the toxic compound in a laboratory setting mimicking a natural
ground water system. This work has been funded by the Swiss Federal Office for
Education and Science within the framework of the EC Environment/Water Program.
In this experiment, solutions containing vinyl chloride, as
well as some mineral salts, were pumped through laboratory columns. The toxic
compound was regularly analyzed in inlet and outlet samples. After several
weeks of cycling, vinyl chloride concentrations began to decrease, reaching
zero after about four months. Ethene, an organic compound often used as a plant
hormone, is one of the possible degradation products.
Christof Holliger, director of the EPFL laboratory, explains
that ethene's outlet concentration always was lower than the inlet vinyl
chloride concentration.
The complete results from this study were published in the
May-June 2011 issue ofJournal of Environmental Quality.