Biodegradation of ¹⁴C-dicofol in wastewater aerobic treatment and sludge anaerobic biodigestion

Abstract

Organic micropollutants are often found in domestic and industrial effluents. Thus, it is important to learn their fate, the metabolites generated and their sorption during biological treatment processes. This work investigated the biodegradation of 14C-dicofol organochloride during wastewater aerobic treatment and sludge anaerobic biodigestion. The performance of these processes was evaluated by physical-chemical parameters. Radioactivity levels were monitored in both treatments, and residues of dicofol (DCF) and dichlorobenzophenone (DBP) were quantified by HPLC/UV. The efficiency of the aerobic and anaerobic processes was slightly reduced in the presence of DCF and DBP. After aerobic treatment, only 0.1% of DCF was mineralized, and 57% of radioactivity remained sorbed on biological sludge as DBP. After 18 days of anaerobiosis, only 3% of DCF and 5% of DBP were detected in the sludge. However, 70% of radioactivity remained in the sludge, probably as other metabolites. Dicofol was biodegraded in the investigated process, but not mineralized.

Assessing Dicofol Concentrations in Air: Retrospective Analysis of Global Atmospheric Passive Sampling Network Samples from Agricultural Sites in India

“…Studies have also investigated the degradation of dicofol to DCBP under different conditions in the environment. ,, In both soil and water, o , p ′-dicofol degrades more rapidly than p , p ′-dicofol to its respective DCBP isomer . Because technical dicofol comprises 80% p , p ′ isomer and 20% o , p ′ isomer, the differing degradation rates between these two dicofol isomers would shift this isomer proportion upon its conversion to its respective DCBP isomers (i.e., >20% o , p ′-DCBP).…”

Fate of the herbicide 14C-atrazine during sewage treatment on a lab-scale bioreactor

“…These results are different from those reported in the literature for other organic micropollutants. Oliveira et al (2012) observed that 60% of 14 C-didofol, an organochlorine acaricide was sorbed by the settled sludge using the same process and they observed a partial biodegradation. Kipopoulou et al (2004) measured a removal of 67% of lindane by sludge with a sewage aerobic treatment and suggested biodegradation of up to 60%.…”

Biodegradation of dicofol by Microbacterium sp. D-2 isolated from pesticide-contaminated agricultural soil

“…Cellulase can degrade DCF, but it is not an organism but an enzyme [28]. Similarly, DCF is biodegraded during wastewater aerobic treatment and sludge anaerobic digestion, but DCF-biodegrading organisms could not be identified [29]. In addition, the degradation time of DCF by bacteria is relatively long, and the degradation efficiency is not high [30].…”