Alachlor and its metabolites in surface water

Biodegradation of alachlor in water was tested in different experimental conditions. This compound is rather persistent since its degradation is lower than 50 % after 28 d of incubation. The highest biodegradation extent was observed at very low concentrations, like those measured in field, or when alachlor is the primary carbon source. About 20 breakdown products were detected and three of them were confirmed by comparison with pure commercial compounds: 2,6-diethylaniline (DEA) and 2′,6′-diethyl-N-2-hydroxy(methoxymethyl) acetanilide (hydroxy-alachlor). DEA was found in Italian surface waters polluted by alachlor. This compound arises concern because it has a high mobility in soil and is a precursor of mutagenic compounds in mammal metabolism.