MSGID: 1:317/3 64781f22   
   PID: hpt/lnx 1.9.0-cur 2019-01-08   
   TID: hpt/lnx 1.9.0-cur 2019-01-08   
    Biological cleanup discovered for certain 'forever chemicals'    
    Two species of naturally-occurring bacteria found to breakdown   
   chlorinated 'forever chemicals,' AKA PFAS    
      
     Date:   
         May 31, 2023   
     Source:   
         University of California - Riverside   
     Summary:   
         Chemical and environmental engineering scientists have identified   
         two species of bacteria found in soil that break down a class of   
         stubborn 'forever chemicals'-- per- and poly-fluoroalkyl substances,   
         or PFAS, that have contaminated groundwater below industrial and   
         military sites throughout the nation. The discovery gives hope   
         for low-cost biological cleanup of these pollutants.   
      
      
         Facebook Twitter Pinterest LinkedIN Email   
      
   ==========================================================================   
   FULL STORY   
   ==========================================================================   
   University of California, Riverside, chemical and environmental   
   engineering scientists have identified two species of bacteria found   
   in soil that break down a class of stubborn "forever chemicals," giving   
   hope for low-cost biological cleanup of industrial pollutants.   
      
   These bacteria destroy a subgroup of per- and poly-fluoroalkyl substances,   
   or PFAS, that have one or more chlorine atoms within their chemical   
   structure, Yujie Men, an assistant professor in the Bourns College of   
   Engineering, and her UCR colleagues, reported in the journal Natural   
   Water.   
      
   Unhealthful forever chemicals persist in the environment for decades   
   or much longer because of their unusually strong carbon-to-fluorine   
   bonds. Remarkably, the UCR team found that the bacteria cleave the   
   pollutant's chlorine-carbon bonds, which starts a chain of reactions   
   that destroy the forever chemical structures, rendering them harmless.   
      
   "What we discovered is that bacteria can do carbon-chlorine bond cleavage   
   first, generating unstable intermediates," Men said. "And then those   
   unstable intermediates undergo spontaneous defluorination, which is the   
   cleavage of the carbon-fluorine bond."  Chlorinated PFAS are a large   
   group in the forever chemical family of thousands of compounds. They   
   include a variety of non-flammable hydraulic fluids used in industry and   
   compounds used to make chemically stable films that serve as moisture   
   barriers in various industrial, packaging, and electronic applications.   
      
   The two bacteria species -- Desulfovibrio aminophilus and Sporomusa   
   sphaeroides-- identified by Men's group are naturally occurring and are   
   known to live in the subterranean microbiomes where groundwater may be   
   contaminated with PFAS. For expedited cleanups, an inexpensive nutrient,   
   such as methanol, could be injected into groundwater to promote bacterial   
   growth. This would greatly increase the bacteria's presence to destroy   
   the pollutants more effectively, Men said. If the bacteria are not   
   already present, the contaminated water could be inoculated with one of   
   the bacterium species.   
      
   The title of the paper is "Substantial defluorination of   
   polychlorofluorocarboxylic acids triggered by anaerobic microbial   
   hydrolytic dichlorination." Men is the corresponding author and Bosen   
   Jin, a UCR chemical and environmental engineering graduate student,   
   is the lead author. Other UCR co-authors are postdoc Jinyu Gao; former   
   postdoc Huaqing Liu; former graduate students Shun Che and Yaochun Yu;   
   and Associate Professor Jinyong Liu.   
      
   The study expands on earlier work by Men, in which she demonstrated   
   that microbes can breakdown a stubborn class of PFAS called fluorinated   
   carboxylic acids.   
      
   Microbes have long been used for biological cleanup of oil spills   
   and other industrial pollutants, including the industrial solvent   
   trichloroethylene or TCE, which Men has studied.   
      
   But what's known about using microorganisms to clean up PFAS is still   
   in its infancy, Men said. Her discovery shows great promise because   
   biological treatments, if effective pollutant-eating microbes are   
   available, are generally less costly and more environmentally friendly   
   than chemical treatments.   
      
   Pollutant-eating microbes can also be injected into difficult-to-reach   
   locations underground.   
      
   Men's latest PFAS study comes as the U.S. Environmental Protection Agency   
   is promulgating new regulations to spur cleanups of PFAS-contaminated   
   groundwater sites throughout the nation because these chemicals have been   
   linked to a host of ill health effects, including cancer, kidney disease,   
   and hormone disruptions.   
      
       * RELATED_TOPICS   
             o Plants_&_Animals   
                   # Bacteria # New_Species # Microbes_and_More # Soil_Types   
             o Earth_&_Climate   
                   # Pollution # Geochemistry # Air_Quality # Air_Pollution   
       * RELATED_TERMS   
             o Soil_contamination o Environmental_engineering o Pesticide   
             o Pollution o Civil_engineering o Endospore o PCB o Soil_science   
      
   ==========================================================================   
   Story Source: Materials provided by   
   University_of_California_-_Riverside. Original written by David   
   Danelski. Note: Content may be edited for style and length.   
      
      
   ==========================================================================   
   Journal Reference:   
      1. Bosen Jin, Huaqing Liu, Shun Che, Jinyu Gao, Yaochun Yu, Jinyong   
      Liu,   
         Yujie Men. Substantial defluorination of polychlorofluorocarboxylic   
         acids triggered by anaerobic microbial hydrolytic   
         dechlorination. Nature Water, 2023; 1 (5): 451 DOI:   
         10.1038/s44221-023-00077-6   
   ==========================================================================   
      
   Link to news story:   
   https://www.sciencedaily.com/releases/2023/05/230531102022.htm   
      
   --- up 1 year, 13 weeks, 2 days, 10 hours, 50 minutes   
    * Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (1:317/3)   
   SEEN-BY: 15/0 106/201 114/705 123/120 153/7715 218/700 226/30 227/114   
   SEEN-BY: 229/110 112 113 307 317 400 426 428 470 664 700 291/111 292/854   
   SEEN-BY: 298/25 305/3 317/3 320/219 396/45   
   PATH: 317/3 229/426