Bioavailability of 2,4-D sorbed to a chlorite-like complex

An Al(OH)(x)-montmorillonite (chlorite) complex (AM(18)) was prepared and 2 ,4-dichlorophenoxyacetic acid (2,4-D) sorbed to saturation. After several w ashing cycles the 'strongly sorbed' 2,4-D was 507 mu g g(-1) AM(18). The bi oavailability of sorbed 2,4-D was assessed in a minimal salts medium with t he AM(18) - 2,4-D as the sole C and energy source. Over a 28-day period a P seudomonas sp. degraded 23% more of the sorbed 2,4-D than could be accounte d for by desorption from AM(18) in the non-inoculated controls. Possible ex planations for the increase in bioavailability are presented. (C) 1999 Else vier Science Ltd. All rights reserved.