Your article on the reaction of nanoparticles of iron with trichloroethane (TCE) contaminating an aquifer, states that the TCE is converted “into ethane.” What happens to the chlorine stripped off the TCE? Is it converted into insoluble inorganic compounds or is it available to react with another aquifer contaminant to possibly form another toxic substance?

Charles McChesney
Mars, Pa

The chlorine atoms stripped from TCE are converted into harmless chloride ions that float freely in the groundwater .—A. Goho