{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,8]],"date-time":"2026-10-08T15:46:24Z","timestamp":1791474384344,"version":"4.3.4"},"reference-count":18,"publisher":"Oxford University Press (OUP)","issue":"4","license":[{"start":{"date-parts":[[2022,10,14]],"date-time":"2022-10-14T00:00:00Z","timestamp":1665705600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/pages\/standard-publication-reuse-rights"},{"start":{"date-parts":[[2022,11,7]],"date-time":"2022-11-07T00:00:00Z","timestamp":1667779200000},"content-version":"vor","delay-in-days":24,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"}],"content-domain":{"domain":["setac.onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2023,7,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n               <jats:p>In situ bioremediation of chlorinated compounds such as perchloroethylene (PCE) and trichloroethylene (TCE) through enhanced reductive dechlorination (ERD) requires appropriate growth conditions for organohalide-respiring bacteria (OHRB). One of the most important factors controlling OHRB metabolism is groundwater pH. Dehalococcoides spp. (DHC) growth may be inhibited when pH is lower than 6.0, which can lead to the accumulation of toxic daughter compounds including cis-dichloroethylene (cDCE) and vinyl chloride (VC). Aquifer pH may decline as HCl is released during reductive dechlorination and from substrate fermentation to fatty acids and carbonic acid. In this article, we demonstrate that using proper pH adjustment and control in situ is an appropriate strategy to achieve complete ERD (i.e., complete conversion of PCE and TCE to nontoxic ethylene) in remediation sites with inherently low pH values and\/or low buffering capacity. To analyze the effectiveness of this approach, field monitoring results are presented for a challenging site containing high concentrations of PCE and TCE (&amp;gt;10\u2009000\u2009\u00b5g\/L and &amp;gt;1000\u2009\u00b5g\/L, respectively) and low aquifer pH (~4.9). Addition of a bioaugmentation culture, emulsified vegetable oil (EVO), and a colloidal buffer (CoBupHTM) to increase pH, stimulated rapid conversion of PCE and TCE to cDCE and VC. However, further conversion of cDCE and VC was very limited. To stimulate complete conversion to ethylene, additional CoBupHTM and nutrients were injected, resulting in a rapid increase in metabolic rates, and maintained the aquifer pH at ~6.5 for more than five years, thus demonstrating that complete ERD can be achieved in sites with similar characteristics. Proper pH adjustment and control is needed to limit the accumulation of toxic intermediates, maintaining in situ bioremediation as an efficient, affordable, and environmentally friendly option to treat chlorinated compounds. Integr Environ Assess Manag 2023;19:943\u2013948. \u00a9 2022 SETAC<\/jats:p>","DOI":"10.1002\/ieam.4696","type":"journal-article","created":{"date-parts":[[2022,10,14]],"date-time":"2022-10-14T07:48:35Z","timestamp":1665733715000},"page":"943-948","update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["The importance of proper pH adjustment and control to achieve complete in situ enhanced reductive dechlorination"],"prefix":"10.1093","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-4473-9064","authenticated-orcid":false,"given":"Juan Fausto","family":"Ortiz-Medina","sequence":"first","affiliation":[{"name":"EOS Remediation LLC Research Triangle Park North Carolina USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bilgen","family":"Yuncu","sequence":"additional","affiliation":[{"name":"Draper Aden Associates Cary North Carolina USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lydia","family":"Ross","sequence":"additional","affiliation":[{"name":"EOS Remediation LLC Research Triangle Park North Carolina USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Brad","family":"Elkins","sequence":"additional","affiliation":[{"name":"EOS Remediation LLC Research Triangle Park North Carolina USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"286","published-online":{"date-parts":[[2022,10,14]]},"reference":[{"key":"2025010717110454200_ieam4696-bib-0001","author":"Borden","year":"2017"},{"issue":"Fall","key":"2025010717110454200_ieam4696-bib-0002","first-page":"28","article-title":"In situ pH adjustment with colloidal Mg(OH)2","volume":"17","author":"Borden","year":"2016","journal-title":"Environmental Engineer & Scientist, Applied Research & Practice"},{"key":"2025010717110454200_ieam4696-bib-0003","doi-asserted-by":"crossref","first-page":"14","DOI":"10.1016\/j.advwatres.2012.04.001","article-title":"Analysis of acidity production during enhanced reductive dechlorination using a simplified reactive transport model","volume":"43","author":"Brovelli","year":"2012","journal-title":"Advances in Water Research"},{"issue":"3","key":"2025010717110454200_ieam4696-bib-0004","doi-asserted-by":"crossref","first-page":"303","DOI":"10.1289\/ehp.1205879","article-title":"Human health effects of trichloroethylene: Key findings and scientific issues","volume":"121","author":"Chiu","year":"2013","journal-title":"Environmental Health Perspectives"},{"issue":"1","key":"2025010717110454200_ieam4696-bib-0005","doi-asserted-by":"crossref","first-page":"128","DOI":"10.1186\/1475-2859-11-128","article-title":"Role of bicarbonate as a pH buffer and electron sink in microbial dechlorination of chloroethenes","volume":"11","author":"Delgado","year":"2012","journal-title":"Microbial Cell Factories"},{"key":"2025010717110454200_ieam4696-bib-0006","author":"Enviro Wiki","year":"2022"},{"issue":"4","key":"2025010717110454200_ieam4696-bib-0007","doi-asserted-by":"crossref","first-page":"325","DOI":"10.1289\/ehp.1307359","article-title":"Human health effects of tetrachloroethylene: Key findings and scientific issues","volume":"122","author":"Guyton","year":"2014","journal-title":"Environmental Health Perspectives"},{"issue":"24","key":"2025010717110454200_ieam4696-bib-0008","doi-asserted-by":"crossref","first-page":"14548","DOI":"10.1021\/acs.est.9b04463","article-title":"Impact of fixed nitrogen availability on Dehalococcoides mccartyi reductive dechlorination activity","volume":"53","author":"Kaya","year":"2019","journal-title":"Environmental Science and Technology"},{"key":"2025010717110454200_ieam4696-bib-0009","author":"Leeson","year":"2004"},{"issue":"1","key":"2025010717110454200_ieam4696-bib-0010","doi-asserted-by":"crossref","first-page":"133","DOI":"10.1016\/j.nbt.2014.02.011","article-title":"In situ groundwater and sediment bioremediation: Barriers and perspectives at European contaminated sites","volume":"32","author":"Majone","year":"2015","journal-title":"New Biotechnology"},{"issue":"16","key":"2025010717110454200_ieam4696-bib-0011","doi-asserted-by":"crossref","first-page":"4560","DOI":"10.1016\/j.scitotenv.2009.03.029","article-title":"pH control for enhanced reductive bioremediation of chlorinated solvent source zones","volume":"407","author":"Robinson","year":"2009","journal-title":"Science of the Total Environment"},{"issue":"29","key":"2025010717110454200_ieam4696-bib-0012","doi-asserted-by":"crossref","first-page":"218","DOI":"10.1180\/claymin.1963.005.29.08","article-title":"Effect of iron oxides on positive and negative charges in clays and soils","volume":"5","author":"Sumner","year":"1963","journal-title":"Clay Minerals"},{"issue":"4","key":"2025010717110454200_ieam4696-bib-0013","doi-asserted-by":"crossref","first-page":"389","DOI":"10.1111\/j.1751-7915.2009.00147.x","article-title":"The little bacteria that can\u2014Diversity, genomics and ecophysiology of \u201cDehalococcoides\u201d spp. in contaminated environments","volume":"3","author":"Ta\u015f","year":"2010","journal-title":"Microbial Biotechnology"},{"issue":"5","key":"2025010717110454200_ieam4696-bib-0014","doi-asserted-by":"crossref","first-page":"1080","DOI":"10.1128\/aem.49.5.1080-1083.1985","article-title":"Biotransformation of tetrachloroethylene to trichloroethylene, dichloroethylene, vinyl chloride, and carbon dioxide under methanogenic conditions","volume":"49","author":"Vogel","year":"1985","journal-title":"Applied and Environmental Microbiology"},{"issue":"1616","key":"2025010717110454200_ieam4696-bib-0015","doi-asserted-by":"crossref","first-page":"20120320","DOI":"10.1098\/rstb.2012.0320","article-title":"Guided cobalamin biosynthesis supports Dehalococcoides mccartyi reductive dechlorination activity","volume":"368","author":"Yan","year":"2013","journal-title":"Philosophical Transactions of the Royal Society of London Series B: Biological Sciences"},{"issue":"15","key":"2025010717110454200_ieam4696-bib-0016","doi-asserted-by":"crossref","first-page":"8579","DOI":"10.1021\/acs.est.7b01510","article-title":"Organohalide respiration with chlorinated ethenes under low pH conditions","volume":"51","author":"Yang","year":"2017","journal-title":"Environmental Science and Technology"},{"issue":"12","key":"2025010717110454200_ieam4696-bib-0017","doi-asserted-by":"crossref","first-page":"2767","DOI":"10.1038\/ismej.2017.127","article-title":"Grape pomace compost harbors organohalide-respiring Dehalogenimonas species with novel reductive dehalogenase genes","volume":"11","author":"Yang","year":"2017","journal-title":"The ISME Journal: Multidisciplinary Journal of Microbial Ecology"},{"issue":"3","key":"2025010717110454200_ieam4696-bib-0018","doi-asserted-by":"crossref","first-page":"475","DOI":"10.1007\/s11802-015-2631-z","article-title":"Hydrochemistry of the natural low pH groundwater in the coastal aquifers near Beihai China","volume":"14","author":"Zhou","year":"2015","journal-title":"Journal of Ocean University of China"}],"container-title":["Integrated Environmental Assessment and Management"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/ieam.4696","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/full-xml\/10.1002\/ieam.4696","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/academic.oup.com\/ieam\/article-pdf\/19\/4\/943\/59563457\/ieam4696.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/academic.oup.com\/ieam\/article-pdf\/19\/4\/943\/59563457\/ieam4696.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,1,7]],"date-time":"2025-01-07T17:45:52Z","timestamp":1736271952000},"score":1,"resource":{"primary":{"URL":"https:\/\/academic.oup.com\/ieam\/article\/19\/4\/943\/7725253"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,10,14]]},"references-count":18,"journal-issue":{"issue":"4","published-online":{"date-parts":[[2022,10,14]]},"published-print":{"date-parts":[[2023,7,1]]}},"URL":"https:\/\/doi.org\/10.1002\/ieam.4696","relation":{},"ISSN":["1551-3777","1551-3793"],"issn-type":[{"value":"1551-3777","type":"print"},{"value":"1551-3793","type":"electronic"}],"subject":[],"published-other":{"date-parts":[[2023,7,1]]},"published":{"date-parts":[[2022,10,14]]},"assertion":[{"value":"2022-03-16","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2022-10-10","order":1,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2022-11-07","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}