Application of biodegradation in mitigating and remediating pesticide contamination of freshwater resources: state of the art and challenges for optimization

Abstract

In recent years, the application of pesticide biodegradation in remediation of pesticide-contaminated matrices moved from remediating bulk soil to remediating and mitigating pesticide pollution of groundwater and surface water bodies. Specialized pesticide-degrading microbial populations are used, which can be endogenous to the ecosystem of interest or introduced by means of bioaugmentation. It involves (semi-)natural ecosystems like agricultural fields, vegetated filter strips, and riparian wetlands and man-made ecosystems like on-farm biopurification systems, groundwater treatment systems, and dedicated modules in drinking water treatment. Those ecosystems and applications impose challenges which are often different from those associated with bulk soil remediation. These include high or extreme low pesticide concentrations, mixed contamination, the presence of alternative carbon sources, specific hydraulic conditions, and spatial and temporal variation. Moreover, for various indicated ecosystems, limited knowledge exists about the microbiota present and their physiology and about the in situ degradation kinetics. This review reports on the current knowledge on applications of biodegradation in mitigating and remediating freshwater pesticide contamination. Attention is paid to the challenges involved and current knowledge gaps for improving those applications.

Genetic (In)stability of 2,6-Dichlorobenzamide Catabolism in Aminobacter sp. Strain MSH1 Biofilms under Carbon Starvation Conditions

“…The bbdD/16S rRNA gene ratio, however, clearly changed. In biofilms originating from the DCBA ϩ inoculum, the bbdD/16S rRNA gene ratios decreased significantly (by factors of 7,10,8,12, and 2 when feeds containing 0, 1, 10, 100, and 1,000 g/liter BAM, respectively, were used). Similarly, biofilms originating from the DCBA Ϫ inoculum became depleted of bbdD when they were grown on 0, 1, …”

“…Either wells that extract BAM-contaminated groundwater intended for drinking water production are closed, or drinking water treatment plants (DWTPs) (4) employ additional expensive treatment steps, such as granular activated carbon (GAC) filtration or ozonation, to lower the BAM concentration below the EU threshold limit (5,6). Bioremediation is suggested as a green and economically sound alternative to remove micropollutants from DWTP drinking water intended for consumption (7,8). Aminobacter sp.…”

“…strain MSH1 is an aerobic soil isolate that mineralizes BAM and uses the compound as C, N, and energy sources (2,9). The organism was proposed as a candidate biological catalyst for bioaugmentation of dedicated filtration units in DWTPs to treat BAM-contaminated intake water (8).…”

Flux, Impact, and Fate of Halogenated Xenobiotic Compounds in the Gut

“…Chlorinated phenoxy acid herbicides such as 2,4-dichlorophenoxyacetic acid ( 10 ), the broad-spectrum chlorinated organophosphate chlorpyrifos ( 11 ) and the herbicide atrazine ( 12 ) are among the most intensively used pesticides worldwide (Bradberry et al, 2000 ; Arias-Estévez et al, 2008 ; John and Shaike, 2015 ). Pesticide contamination from specific point sources (μg/L to mg/L range) can be due to accidental releases at manufacturing plants, spills on farm yards and from wastewater treatment plant effluent (Vandermaesen et al, 2016 ). In contrast, diffuse contamination (ng/L to μg/L range) originates from actual pesticide application that results in large-scale contamination of groundwater through leaching, and contamination of surface water through runoff, erosion, drainage, and drifting (Holvoet et al, 2007 ).…”

Microbial transformation of organic and inorganic halogen compounds

“…Understanding biodegradation bottlenecks has been a major objective in efforts to harness the metabolic potential of microorganisms for bioremediation of sites contaminated with organic pollutants (Atashgahi et al 2018;Meckenstock et al 2015;Vandermaesen et al 2016). An important class of such contaminants comprises chlorinated solvents such as chloroethenes, chloroethanes and chloropropanes that have adverse effects on human and environmental health (EPA 2018;Weatherill et al 2018).…”