对付林丹残留的新方法

For many years two companies located in Bizkaia, Bilbao Chemicals (Barakaldo 1947-1987) and Nexana (Erandio 1952-1982), had been manufacturing lindane（林丹） and dumping it into the environment with no control whatsoever¹. Today we have become aware of the need to solve the problems caused by this dumping and the difficulty in achieving this since there is no viable² process that will safely destroy the lindane mixed with the soil. A study by the UPV/EHU's Department of Physical Chemistry and Analytical³ Chemistry in collaboration⁴ with Tecnalia has confirmed the hypothesis of the high reactive capacity of iron nanoparticles to degrade lindane. The study has been published in the journal Chemosphere.   Lindane has been routinely used among farmers as an insecticide and pesticide⁵, and although its use has now been banned, the consequences of lindane manufacture and use have not disappeared. The risk posed by lindane lies in the fact that it is not only toxic⁶, it can be accumulated in living organisms. From an environmental point of view, it has low solubility⁷（溶解度）, high stability and high persistence⁸ and resistance to degradation⁹ in the environment.   Although there is as yet no viable process for safely destroying lindane, an innovative¹⁰, efficient alternative is to use iron nanoparticles. Iron nanoparticles have shown themselves to be very effective as a decontaminating agent when it comes to handling various families of highly toxic compounds like lindane. However, they have a number of drawbacks that limit and hamper¹¹ their application, since they oxidize easily in the presence of air and their tendency to agglomerate¹² limits their mobility¹³ in the medium in which one is seeking to apply them. So the need to protect them is done by using Carboxymethyl cellulose (CMC), polyaspartate (PAP) and poly (acrylic acid) (PAA) as biodegradable polymer coatings.