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This review article discusses the current state of knowledge on water treatment and reuse by biofiltration systems focusing on biologically enhanced activated carbon (BAC) process. First, the applications of BAC in water treatment systems are overviewed, and then, the mechanisms for both biofilm formation and contaminant treatment are discussed along with the operational parameters influencing the performance of BAC process. Since contaminant removal by BAC is governed by adsorption and biodegradation, both processes are reviewed in relation to the treatment mechanisms. Information on removal of recent emerging contaminants including nitrogenous and unregulated disinfection by‐products (DBPs) and their precursors, poly‐ and perfluorofluoroalkyl substances, nanoparticles, and plasticizers and microplastics by BAC is given along with suggestions for treatment improvements and future research. The uniqueness of this review includes insights on relevant biofilm aspects and the coverage on the abilities of BAC for treatment of recent and less common emerging contaminants especially unregulated DBPs and their precursors, nanoparticles, and plasticizers and microplastics. For future BAC studies, recommendations are proposed on exploring the biofilm development on media and recent emerging contaminants as co‐contaminants, as well as developing novel supporting materials such as biochar. Practitioner points: The amount and the physiology and physical structure of biofilm affect the treatment efficiency of biological activated carbon.Biological activated carbon is capable of removing a majority of nitrogenous and unregulated disinfection by‐products.Whether and how biological activated carbon is impacted by and/or can remove nanoparticles, and plasticizers and microplastics remain largely unknown.Future work on biological activated carbon should focus on biofilm evolution and control, and novel support materials. [ABSTRACT FROM AUTHOR]

Profenofos (PF) is one of the heavily used organophosphorus pesticides (OPPs) of which its contamination is ubiquitous in an agricultural area. This study aims to acquire and characterize PF-degrading bacterial cultures from contaminated soil. OPP degradation by the novel isolates was then investigated. The experiment was performed at the initial PF concentration of 20 mg/L. The result showed that the enriched consortium comprised three predominant PF-degrading strains designated as PF1, PF2, and PF3. The isolates (PF1, PF2, and PF3) were characterized as Pseudomonas plecoglossicida, Pseudomonas aeruginosa, and P. aeruginosa, respectively. A consortium and all isolates could utilize PF as a sole carbon source with PF removal of more than 90 % via a hydrolysis process. The bacterial growth and PF degradation rates followed the first-order kinetic reaction with the rates of 0.4 to 2.7/h and 0.15 to 1.96/h, respectively. Additional carbon supplement deteriorated PF biodegradation. The enriched cultures were also capable for degrading chlorpyrifos and dicrotophos pesticides (33-73 % removal). The results indicated that the consortium and isolates are efficient for PF and other OPP degradation and have potential for PF remediation. [ABSTRACT FROM AUTHOR]

Background: Chlorpyrifos and profenofos are organophosphate pesticides (OPPs), we studied exposure and urinary metabolites in an agricultural area in the northeastern of Thailand during the chili-growing season (March - April) in 2012., Objective: This study was designed to assess pesticide exposure concentration through dermal and inhalation pathways and to find and depict a relationship between urinary metabolites and means of exposure., Materials and Methods: To estimate the pesticides exposure concentration, dermal wipes (hand, face, and feet), dermal patches and air samples were collected from 38 chili farmers. The morning void of pre and post application urine samples was an indicator of biological monitoring in the study which derived from 39 chili farmers., Results: Chlorpyrifos and profenofos residues were detected on dermal patches, face wipes, and hand wipe samples, while no significant residues were found on the feet. Using a personal air sampling technique, all air samples detected pesticide residues. However, significant correlation between dermal pesticide exposure concentration and inhalation was not found (p>0.05). For urinary metabolite levels, there was a relationship between the first pre application morning void and post application morning void (p < 0.05); similar to the association between the first pre application morning void and the second post application morning void (p < 0.05). The main relationship between pesticide exposure and urinary metabolite was found to have been relevant to dermal exposure (r= 0.405; p < 0.05)., Conclusions: The results of this study could suggested that public health education training programs, including the use of appropriate personal protective equipment (PPE), should be offered for the chili growing farmers in order to improve their ability to properly use pesticides., Key Words: pesticide exposure, chili farmers, urinary metabolites, organophosphate pesticides.