BCI to Report Significant Research Findings on PCB Dechlrorination at Battelle Conference
Bioremediation Consulting, Inc. will present recent research findings on dechlorination of PCBs at the Battelle Conference - "Remediation of Chlorinated and Recalcitrant Compounds", May 21-24, 2012 in Monterey, California. BCI's research PCB Biodegradation by a Dehalococcoides (Dhc) Culture Grown on Trichlorobenzenes can be found at Poster Location 17 on Level 1 in the Exhibit Hall from Wednesday, May 23rd at 7 am to Thursday, May 24th at 1:30 pm. The poster will be staffed on Wednesday, May 23rd from 11:00 am to 12:45 pm.
The research showed significant anaerobic biodegradation of PCB's using BCI's strain of sediment-free Dehalococcoides (Dhc) The PCB-degrading culture was tested on three commercial mixtures of PCB's (Aroclor 1260, 1254, and 1242). Within ten weeks of incubation a significant portion of the PCBs having five to eight chlorine atoms per biphenyl were dechlorinated to PCBs having two to five chlorine atoms per biphenyl.
The research was funded by a National Science Foundation Small Business Innovation Research grant. As a result of this research, BCI is now able to offer the first commercially available sediment-free PCB-degrading culture for microcosm testing or bioaugmentation. Since low chlorinated PCBs are readily aerobically degradable, this breakthrough will support sediment remediation by sequential anaerobic-aerobic processes.
BCI Poster at Battelle Focuses on Vinyl Chloride Aerobic Degradation in Groundwater
BCI will have a second poster on display at the Battelle Conference in Monterey, CA which documents an innovative approach to eliminating Vinyl Chloride by harnessing the biodegradation capabilities of three types of bacteria. The topic of the poster is Aerobic Vinyl Chloride Metabolism in Groundwater Microcosms by Methanotrophic and Ethenetrophic Bacteria. It is number 66 in Group E7 and will be on display on the third floor of the Conference Center on Wednesday, May 23rd from 7:00 am to Thursday, May 24th at 1:00 pm. The poster will be staffed on Wednesday, May 23rd from 11:00 am to 12:45 pm.
This research project reveals a novel finding that could change the basic understanding of how vinyl chloride get biodegraded under aerobic conditions. BCI scientists, together with Tim Mattis of the University of Iowa have discovered that methane oxidizing bacteria are able to accelerate biodegradation of VC by "inducing" a second group of VC degrading bacteria, the ethenotrophs, to shorten the lag time for the biodegradation of VC. This findings will play an important role in using MNA to achieve VC clean up goals. The research was funded by SERDP.
BCI obtains permit from the Department of Agriculture to receive soil samples from abroad
A permit to obtain soil samples from outside the U.S. will allow BCI to provide lab-based microbiological consulting to our international clients who are involved in bioremediation of contaminated sites.
With moist or saturated soil samples, BCI will perform laboratory experiments on the ability of anaerobic bacteria such as Dehalococcoides to reductively dechlorinate TCE to ethene. Alternatively, the degradative ability of aerobic soil microbes present in soil to biodegrade chemicals of concern can also be investigated by BCI’s microbiologists. The results of such investigations can be presented to clients to elucidate site characteristics and microbial capabilities as well as to provide conceptual designs for site remediation.
BCI Lab Studies Lead to Client Success in Field
Superfund Site in PA
Problem: Degrade TCE in the presence of 1,1,1-TCA
They said it couldn’t be done. Most strains of Dehaloccoides (Dhc) would not dechlorinate TCE in the presence of 1,1,1-TCA.
BCI Lab in 2005
BCI developed the first strain of Dhc that could resist TCA toxicity at concentrations of TCA as high as 15 ppm. BCI’s successful culture contained both a TCA-resistant Dhc and TCA-degrading Dehalobactor strain.
In the Field: 2006-2012
BCI’s culture was successful in bioaugmenting the Superfund site in Malvern, PA for both the pilot project and for the full-scale project (see p. 15 in the “Second Five-Year Report for Malvern TCE Superfund Site, Malvern Township, Chester County, PA www.epa.gov/superfund/sites/fiveyear/F2010030003657.pdf).
Industrial Site in IN
Problem: Degrade TCE in the presence of 100 ppm 1,1,1 TCA
BCI’s client requested that BCI develop a Dhc strain for the treatment of a source zone groundwater containing upwards of 100 ppm each of TCA and TCE. The increased concentrations of contaminants presented a formidable challenge.
BCI Lab in 2011
Using a unique microbial adaptation method, BCI developed a mixed culture of TCA-resistant Dhc and Dehalobactor strains able to degrade 100 ppm each of TCA and TCE.
In the Field: 2011-2012
The engineering client insured that sufficient electron donor mineral amendments were available and that the pH conditions at the site were suitable. 80 liters of culture were shipped to the client in late summer 2011 and used for bioaugmentation. Early results indicate that the culture is growing in situ and biodegrading both TCE and TCA.
June 2011BCI Receives National Science Foundation Small Business Innovation Research Grant for PCB Degradation by Dhc which dechlorinate aromatic compounds
Principal Investigator, Dr. Margaret Findlay will lead BCI’s research effort on the development of a commercial culture of Dehalococcoides (Dhc) for anaerobic degradation of PCBs.
March 18th 2011BCI Offers Low-pH Tolerant Dehalococcoides (Dhc) Culture
Bioremediation Consulting, Inc (BCI) of Watertown, MA announced today that it has completed development of a culture of low-pH tolerant Dehalococcoides (Dhc) bacteria to treat groundwater contaminated with chlorinated solvents such as tetrachloroethene (PCE) and trichloroethene (TCE), converting them to the harmless end product ethene at pH as low as 5.6.
BCI’s new culture dechlorinates PCE and TCE in much more acidic groundwater than can be tolerated by other commercial cultures of Dhc. This breakthrough addresses one of the most pervasive and persistent problems in bioremediation of groundwater contaminated with chlorinated solvents. That problem is acidification of the groundwater during treatment which is a result of the biodegradation process itself, and can be exacerbated by application of excess electron donor. Using a low-pH tolerant bacterial culture can be a cost effective means of reducing the amount of buffering compounds needed to adjust the pH of treatment areas.
The development of the low-pH tolerant Dhc Culture was funded by the National Science Foundation through a Small Business Innovation Research (SBIR) grant awarded in 2010. BCI has been involved in cutting-edge research in the field of bioremediation for over 20 years and continues to advance the frontiers of this technology.
This new culture has been added to BCI’s catalog of Designer Bacteria™(DB) and provides a powerful new tool for many clients. In addition to TCE, BCI has developed a wide range of Designer Bacteria™ to treat chlorinated benzenes, ethenes, ethanes and PCBs. BCI’s Designer Bacteria™ are grown in client’s groundwater prior to field inoculation, to address specific site requirements and to insure success of in situ bioremediation.
The new low-pH tolerant culture is now available to commercial clients. Contact Sam Fogel for more information at firstname.lastname@example.org.
October 2009BCI Awarded National Science Foundation Small Business Innovation Research Grant
Principal Investigator, Dr. Margaret Findlay will lead BCI’s research effort on Dehalococcoides (Dhc) function in the subsurface.
September 2009BCI Presents at Beijing Normal University in Beijing, China
Dr. S. Fogel and Dr. M. Findlay gave a lecture at Beijing Normal University in Beijing China on September 24th on the topic of In Situ Bioremediation using Dehalococcoides to reductively dechlorinate TCE. The lecture was hosted by Dr. Chunye Lin of the School of Environment and attended by 25 professors and graduate students. The response was enthusiastic with many questions. BCI believes it has established a strong basis for future cooperation with the School of Environment.
August 2009Monitored Natural Attenuation by Methane-oxidizing and Ethene- oxidizing Bacteria
BCI scientists completed their first microcosm evaluation of groundwater in support of aerobic monitored natural attenuation (MNA). Some bacteria such as Dehalococcoides (Dhc) grow and biodegrade a variety of chlorinated compounds only under strict anaerobic conditions. BCI has performed hundreds of microcosm tests for anaerobic bacteria such as Dhc. Other bacteria require aerobic conditions to metabolize chlorinated contaminants. The conditions at a site may include separate aerobic and anaerobic zones. These zones may change over time and the separation of these zones may not be static or distinct. The groundwater from a Superfund Site located in EPA Region 5 contained low levels of vinyl chloride (VC) and cis-DCE. After reviewing existing site data, BCI concluded that it was consistent with cycling aerobic/anaerobic conditions producing methane and ethene which supported aerobic co-oxidation of VC and cDCE. A microcosm study with groundwater from 3 wells at this site strongly supported the role of aerobic biodegradation by both methane and ethene-oxidizing bacteria. BCI determined that VC and cDCE were being destroyed predominantly by aerobic microbial processes.
This is one of the first microcosm tests performed aerobically for both methanotrophs and ethenotrophs. The results provided a strong line of evidence in support of MNA under aerobic conditions.
July 2009Bioremediation Consulting Inc (BCI) announced that on June 16, 2009 EPA (Region III) changed the Record of Decision groundwater remedy at the Malvern TCE Superfund Site (Malvern, Pennsylvania) from pump and treat to accelerated in situ bioremediation. EPA’s decision to issue this significant change was based on the success of BCI’s bioremediation approach and its unique dechlorinating culture used in a 3-year pilot study. The remediation project is being expanded to full scale with operation scheduled to begin in September 2009. BCI has a consulting arrangement with the prime Site remediation contractor, O’Brien & Gere, to provide bioremediation consulting and bacterial culture for inoculation into the Site’s subsurface treatment area. The BCI culture used at Malvern contains a Dehalococcoides (Dhc) strain that tolerates the presence of 1,1,1-trichloroethane (TCA), a contaminant that inhibits most native strains of Dhc. For sites contaminated with TCA and 1,1-dichloroethane (DCA), BCI provides cultures containing Dehalobacter species able to reductively dechlorinate TCA and DCA to chloroethane.
June 2009Bioaugmentation Cultures available at Bioremediation Consulting Inc (BCI)
BCI offers a new anaerobic bacterial culture for dechlorination of chloroform
Background: Isolation of Pure Strains. The first Dehalococcoides (Dhc) isolated as a pure culture was Dehalococcoides ethenogenes strain 195. Several additional strains of Dhc have been isolated, however, these pure strains cannot be used directly for bioaugmentation as they require “helper” bacteria termed a microbial consortium.
Microbial Consortia Cultures Used for Remediation. The cultures used for inoculation of contaminated sites by BCI contain the full microbial consortia of interactive anaerobic bacteria that produce a stable environment able to sustain the dechlorinating bacteria. The most important difference between pure cultures of Dhc and a consortia is the presence of anaerobes which degrade organic compounds such as sugars, oils, organic acids, or alcohols, thereby producing H2 required by the Dhc. Mixed cultures also contain sulfate-reducing bacteria which compete for donor but whose reductive process lowers the oxidation-reduction potential (ORP) to a value (-180 mv) which allows dechlorinating bacteria to survive. Methanogens, which grow on H2+CO2 or on acetate, assist in the dechloriantion process by producing B12, which is needed by the dechlorinators. Some sulfate-reducers as well as acetogens also produce B12 .
Origin and Maintenance of Stock BCI Mixed Cultures. BCI obtains its dechlorinating microbial consortia by combining ground water from several contaminated sites which were undergoing natural dechlorination. Cultures are maintained in mineral salts media plus vitamin B12 in sealed containers, and transferred using anaerobic technique. Electron donors such as the organic acid lactate, emulsified soy oil, or sugars (glucose, fructose) are added, as well as the contaminants to be degraded. Cultures are sampled at intervals to monitor the dechlorination of each contaminant and production of ethene, as well as the utilization of donor and the accumulation of organic acids.
Dechlorinating Bacteria in BCI Cultures. To address single compounds or a mixture of chlorinated ethenes, BCI cultures contain at least two types of Dhc (based on genetic evidence for two types of VC-reductase). Specialized BCI cultures also include Dhc which tolerate the presence of 1,1,1-TCA, which inhibits most native Dhc. For sites contaminated with 1,1,1-TCA and 1,1-DCA, BCI provides cultures containing Dehalobacter species. BCI also maintains Dhc cultures which dechlorinate 1,2-dichloroethane, 1,2-dichloropropane, and highly chlorinated chlorobenzenes.
BCI’s newest culture can transform chloroform to carbon dioxide. The transient intermediate, dichloroemthane is briefly formed and then converted to carbon dioxide. We have demonstrated that the culture can convert 10 ppm of chloroform to carbon dioxide.
April 2009Hear BCI's Sam Fogel make two presentations at the Battelle conference in Baltimore on May 6 and May 8th. The first is on the importance of pH in the biodegradation of chlorinated solvents, and the second is on biodegradation of PCBs in soil.
- Wednesday in Session C3 scheduled to begin at 1:25 p.m. The Importance of pH in Reductive Dechlorination of Chlorinated Solvents
- Friday in Session E7 scheduled to begin at 8:00 a.m. Enhanced Microbial Dechlorination of PCBs in Soil
February 2007BCI Scientists and its engineering clients submitted four abstracts for presentation at the Ninth International Battelle Conference "In Situ and On-Site Bioremediation Symposium” to be held in Baltimore Md in May 2007:
- TCA-Tolerant D. ethenogenes Cultures to Biodegrade Chlorinated Compounds in In Situ
- Lessons Learned as a Result of Completing 250 Microcosm Studies
- Dioxane-Degrading Propanotrophs for In Situ Remediation
- Initial Site Assessment for Dehalococcoides Using PCR and Ethene Concentration: Comparison with Microcosm Results
January 2007Bioremediation Consulting Inc. has acquired the environmental testing and distribution rights for the only known anaerobic benzene degrading culture. The bacterium, Dechloromonas Strain RCB, anaerobically degrades benzene, using nitrate as the electron acceptor. In addition to benzene (B), this bacterium is able to anaerobically biodegrade toluene (T), ethylbenzene (E) and xylenes (X), making it metabolically very versatile. The unique microorganism was discovered by John Coates, while a professor at Southern Illinois University.
BCI acquired the rights to test this organism from BioInsite, LLC, an environmental technology firm located in Carbondalel, IL. The potential application of this culture for in-situ treatment is exciting since BTEX chemicals are the most common groundwater contaminants in the U.S., and are routinely biodegradable only under aerobic conditions. Anaerobic bioremediation is preferred as oxygen is difficult and expensive to add to groundwater due to its low solubility. Since most groundwater is already anaerobic, in-situ anaerobic treatment via bioaugmentation with Dechloromonas is potentially highly cost-effective.
BCI’s goal is to use Dechloromonas Strain RCB as a bioaugmentation culture for in-situ treatment of groundwater contaminated with BTEX. The intended approach is similar to that currently being used for in situ treatment of chlorinated solvent sites. In the case of TCE and TCA, BCI acclimates its unique dechlorinating cultures to site groundwater conditions, growing from 10 to 50 liters of high density culture in site groundwater in the lab, followed by inoculation of field groundwater.
BCI is interested in partnering with firms who will support testing efforts both in the laboratory and field for BTEX biodegradation by Dechloromonas strain RCB.
November 2006BCI delivered 38 liters of a unique dechlorinating culture for inoculation of a bedrock aquifer site containing approximately 5 ppm of TCA, 60 to 100 ppm of TCE and cDCE, as well as 2 to 5 ppm of chloroform. BCI’s dechlorinating culture was grown in site groundwater, a practice routinely used by BCI to insure maximum adaptation of its culture to site groundwater conditions. The bioaugmentation culture consisted of a mixture of two dechlorinating bacteria, a TCA-degrader (Dehalobacter spp.) and a TCA-resistant Dehalococcoides ethenogenes. Our bioaugmentation culture is not inhibited by chloroform due to its ability to reductive dechlorinate chloroform. At the client’s request, the culture was further adapted for growth with methanol and ethanol as the primary electron donors.
Prior to bioaugmentation, the culture was analyzed by quantitative PCR (Microbial Insights). The cell density results were: 3 x 108 cells/ ml (Dehalococcoides) and 3 x 107 cells/ ml of Dehalobacter.
A graph of the dechlorination of TCA and TCE during culture growth is shown:
October 2006The article Biodegrade Chlorinated Compounds was published in the October 2006 issue of Pollution Engineering. The article describes BCI's development of mixed cultures of TCE and TCA-degrading microorganisms (Dehalococcoides ethenogenes and Dehalobacter) for use in bioaugmentation of sites contaminated with both types of chlorinated compounds. Most strains of Dehalococcoides are inhibited by the presence of TCA. BCI's culture is a TCA-tolerant Dehalococcoides. Read the article here.
September 2006BCI soil study shows evidence for reductive dechlorination of the pesticide Toxaphene
Toxaphene is a pesticide whose use was banned by the EPA in 1982. Due to its persistence, toxaphene is still found today as a contaminant in some soils. Toxaphene is a complex mixture of approximately 200 chlorinated camphenes with a chlorine content of 68%, and an average of eight chlorines per molecule.
A soil from Texas containing 1,000 ppm each of Toxaphene and DDT was subjected to anaerobic treatment to determine if biotransformation or biodegradation would result. BCI scientists made the soil anaerobic by amending with whey and manure, then inoculated with anaerobic bacteria and incubated for 148 days. Confirmation of anaerobic conditions was based on production of methane and molecular hydrogen, as well as reduction of sulfate. Gas chromatographic evidence showed that the more highly chlorinated toxaphene congeners underwent significant dechlorination with transformation to less chlorinated toxaphene congeners.
August 2006BCI’s propane-oxidizing cultures biodegrade NDMA
The groundwater contaminant N-nitrosodimethylamine (NDMA) (CH3)2N-N=0) is a carcinogen that is widely present in the environment. It is a byproduct of drinking water treatment, due to the formation of chloramines as a key intermediate. Major releases of NDMA have occurred from the manufacture of pesticides, rubber tires and alkyamines. The work of Sharp et al. (2005, Biotechnology and Bioengineering. 89:608, showed that NDMA was biodegradable by bacteria possessing monooxygenase enzymes including methanotrophs, and propanotrophs.
BCI’s propanotrophic enrichment cultures have recently been shown to rapidly biodegrade NDMA. Investigators at the University of CA, Berkeley, recently studied four of BCI’s cultures. Results showed all cultures were able to rapidly biodegrade NDMA. Propane-oxidizing bacteria are also known to co-metabolize a wide range of groundwater contaminants. Scientists at BCI have developed several enrichment cultures of propanotrophs that can biodegrade 1,4-dioxne, TCE, as well as TCA and respective daughter products.
July 2006Effect of 9,000 ppm sulfate with 4,000 ppm chloride on BCI’s D.etheneogenes culture.
BCI has recently completed a microcosm project which demonstrated the adaptability of our D. ethenogenes culture to extreme environments. We tested BCI cultures on a TCE-containing well sample which had exceptionally high concentrations of sulfate (9,000 ppm) and chloride (4,000 ppm).
The successful results were obtained by bioaugmenting the site water with two BCI cultures. The first bioaugmentation culture contained dechlorinators that had been growing in a media containing 1,400 ppm Chloride, with 150 ppm added TCE. The second bioaugmentation culture consisted of sulfate-reducing bacteria which had been growing in media containing 5,200 ppm chloride and 320 ppm sulfate and relatively low concentrations of TCE.
The mixed bioaugmentation culture succeeded in dechlorinating the TCE to ethene in 112 days. Even more interesting was the fact that dechlorination to ethene was accomplished in the presence of most of the original sulfate (between 4,000 and 2,500 ppm during dechlorination). As a result, much less of the donor (whey) was required to achieve complete dechlorination.
April 2006Objectivity is an important BCI value! We raise this point because engineering firms with so-called “captive” laboratories have inherent difficulties with potential conflicts of interest when it comes to providing objective consulting advice. In contrast, BCI is the only independent bioremediation consulting firm in North America able to provide engineering clients with the full range of laboratory services required for successful chlorinated solvent remediations, including: microcosm testing, genetic testing, field monitoring services, site-specific culture development, and bioaugmentation cultures. Our independence is important since our primary business is to help engineering and environmental firms achieve successful remediation. BCI does not perform field remediations!
March 2006As interest grows in the bioremediation of groundwater contaminated with both TCA and chlorinated ethenes, BCI is learning that TCA-degrading bacteria are more widespread than previously thought. Recently, BCI isolated three new cultures from locations in the Northeast and the Midwest capable of degrading TCA to chloroethane, as well as chlorinated ethenes to ethene. BCI obtained these cultures using its proprietary method of “cultural co-evolution”, a culturing/growth technique, which resulted in TCA-degrading bacteria thriving at the same time Dehalococcoides reductively dechlorinated chlorinated ethenes to ethene. Another factor which separates BCI from the pack of newly emerging “bug” salespeople is that for over 15 years, BCI has successfully applied our site-specific microbiological approach to bioremediation of chlorinated solvents. This means that before BCI recommends a remedial approach such as bioaugmentation, we will help clients interested in degrading TCA determine if a potentially less expensive approach, such as biostimulation, is a viable option. BCI evaluates the biostimulation option through a series of steps; including:
- Review historic site data
- Identify data gaps
- Obtain current groundwater quality data
- Perform genetic tests, and
- Perform microcosm test
February 2006BCI’s PCR-based identification of environmental microbes has been expanded to include the genus Dehalobacter, which is known to contain organisms involved in dehalorespiration of chlorinated ethanes and ethenes. Unlike other genera, such as Dehalococcoides, Dehalobacter is not inhibited by the presence of 1,1,1-trichloroethane (TCA). Normally, biological reductive dechlorination of trichloroethene (TCE) by Dehalococcoides is inhibited by the presence of 1,1,1-trichloroethane (TCA). BCI has a mixed culture of Dehalococcoides and Dehalobacter that not only completely dechlorinates TCE to non-toxic ethene in the presence of TCA, it also degrades TCA to chloroethane.
Because of the broad spectrum of compounds dechlorinated by Dehalobacter sp., it is emerging as a significant contributor of dechlorination in the field of bioremediation. Dehalobacter has been associated with the dechlorination of:
- 1,1,1-trichloroethane to 1,1-dichloroethane to chloroethane
- 1,1,2-trichloroethane to vinyl chloride
- 1,2-dichloroethane to ethene
- tetracholorethene to trichloroethene to cis-dichloroethene
This new genetic screening service costs $ 275 per groundwater sample and will include a highly sensitive VOA analysis for chlorinated ethanes and ethenes. For more information regarding BCI’s services, contact Samuel Fogel at BCI. (617) 923-0976; email: email@example.com
January 2006BCI's unique TCA/TCE-degrading mixed culture is in high demand. Normally, biological reductive dechlorination of trichloroethylene (TCE) is inhibited by the presence of 1,1,1-trichloroethane (TCA). BCI has a culture that not only completely reductively dechlorinates TCE to ethene in the presence of TCA; it also degrades TCA to chloroethane. Since a large number of contaminated sites often contain multiple chlorinated chemicals, this mixed culture is a significant advancement in the field of bioremediation, hence its high demand.
Most recently, we made our 7th shipment of this dechlorinating culture for bioaugmenting a site in N.J.
November 2005BCI Announces Bioaugmentation Cultures For Use in Extreme Groundwater Environments
It has been reported that under some extreme environmental conditions such as high concentrations of chloroform, reductive dechlorination by Dehalococcoides is inhibited*. In response, BCI has developed bioaugmentation cultures with abilities to dechlorinate under conditions which normally inhibit non-BCI cultures. These new BCI bioaugmentation cultures of Dehalococcoides include cultures which are:
- Chloroform resistant
- Chloroform dechlorinators
- TCA resistant
- TCA dechlorinators
- Reductive dechlorinators of 300 ppm TCE
*Strains of Dehalococcoides such as KB-1 are reported to be inhibited by low concentrations of TCA (i.e. 0.7 ppm) and chloroform (some inhibition observed at 50 ppb, complete inhibition at 300 ppb CF) Duhamel et al. 2002."Comparison of anaerobic dechlorinating enrichment cultures maintained on tetrachloroethene, trichloroethene, cis-dichloroethene and vinyl chloride". Water Research 36:4193-4202.
September 2005BCI and its engineering clients submitted five abstracts for presentation at the Fifth International Battelle Conference "Remediation of Chlorinated and Recalcitrant Compounds" to be held in Monterey CA in May 2006:
- LESSONS LEARNED AS A RESULT OF COMPLETING 200 MICROCOSM STUDIES
- BIOAUGMENTATION CULTURE ACCLIMATION TROUBLESHOOTING IN INITIALLY INHIBITORY GROUND WATER CONDITIONS
- BIODEGRADATION OF NEAR-SATURATION CONCENTRATIONS OF TCE IN SITE GROUNDWATER: SELECTION OF TREATMENT STRATEGY
- ENHANCED REDUCTIVE DECHLORINATION OF NEAR SATURATION LEVELS OF TCE
- AEROBIC ETHENE BIOSTIMULATION TREATMENT OF LOW CONCENTRATION VINYL CHLORIDE IN GROUNDWATER
August 2005BCI welcomes its new environmental microbiologist, Dominic Vacca. Dominic has a B.S. in Biology (minor in Chemistry), and a M.S. in Soil Science from the University of Wisconsin. His Master’s thesis work, as well as a recent publication, demonstrated improved biodegradability of polynuclear aromatic hydrocarbon (PAH) phenanthrene when bound to soil organic matter. He also developed a unique method for isolation of PAH degrading bacteria with capabilities for biodegrading sorbed contaminants. These achievements are of particular importance for the isolation and enrichment of microorganisms with unique biodegradative abilities, which is one of BCI’s services. D. Vacca’s paper “Isolation of Soil Bacteria Adapted to Degrade Humic Acid-Sorbed Phenanthrene” was published in the August, 2005 issue of the Journal “Applied and Environmental Microbiology” (71: 3797-3805).
July 2005One of BCI’s goals is to help its engineering clients biodegrade TCE at concentrations approaching saturation (~1,000 ppm). Our efforts to date are focused on developing special bioaugmenation cultures able to convert TCE to ethene in the presence of high concentrations of TCE, while efficiently managing issues of culture growth such as pH control, mineral and trace nutrient requirements, and molecular hydrogen formation.
As of July, we successfully achieved reductive dechlorination of 140 ppm of TCE and 15 ppm cis-DCE to 75 % ethene (on a molar basis) in site groundwater using BCI's bioaugmentation culture (BCIe). Efforts to reductively dechlorinate higher concentrations of TCE are continuing, and will be reported when results are obtained.
June 2005As part of BCI’s desire to maintain the highest possible quality control on our bioaugmentation cultures, we recently used an outside laboratory to quantitatively evaluate cell density on a culture of Dehalococcoides. The results indicate that our routine culturing procedure for Dehalococcoides ethenogenes, produces cultures with a cell density of approximatly 2 x 108 cells per ml. When culture density was determined using vinyl chloride-specific primers (BAVI VC- Rdase), the resulting cell density was 2.2 x 107 cells per ml. (Microbial Insights performed the quantitation.)
BCI’s cultures are always grown in site groundwater in order to achieve the highest degree of acclimation. We believe that providing high densities of acclimated dechlorinating bacteria will significantly shorten the time required for site clean up.
May 2005BCI has developed methods for the enumeration and enrichment of “gasotrophs” from groundwater. Gasotrophs are naturally occurring bacteria capable of using mono-oxygenase enzymes to metabolize alkanes and alkenes. Gases such as methane, ethane, ethene, propane, propene, butane or butene are consumed under aerobic conditions. Gasotrophs are of interest due to their ability to co-metabolize a wide variety of contaminants. For example, it has been shown by BCI scientists and others, that contaminants such as chlorinated solvents, 1,4-dioxane, and MTBE, are able to be biodegraded co-metabolically.
April 2005BCI’s Dehalococcoides culture has been successfully grown at concentrations of cis-DCE and TCE greater than 100 mg/L. Efforts are underway to attain growth in concentrations of TCE as high as 1000 mg/L.
March 2005To insure that BCI’s cultures are successfully used, we have established a policy for sale of our cultures. BCI offers a teaming relationship with engineering and environmental firms planning to bioaugment sites with our dehalorespiring cultures. Our efforts are intended to insure that site groundwater, prior to inoculation, will have a redox potential suitable for survival of Dehalococcoides, as well as sufficient electron donor and concentrations of phosphate and ammonia to permit in-situ growth of Dehalococcoides.
February 2005BCI is preparing to ship a batch of its unique TCA-degrading mixed culture to a field bioaugmentation project in Texas. Our mixed culture “breaths” chlorinated solvents, a process termed “dehalorespiration”. BCI’s TCE/TCA Culture consists of two different dechlorinating bacteria, Dehalococcoides ethenogenes, a high-rate TCE degrader, and a TCA-degrader (unrelated to D. ethenogenes). Both organisms degrade their respective chlorinated compounds simultaneously. BCI’s strain of Dehalococcoides is not inhbited by TCA.
January 2005Two abstracts were submitted by BCI scientists for presentation in Oct 2005, at the U.Mass Soils, Sediments, and Water Conference in Amherst, MA:
December 2004We previously reported that vinyl chloride could be biodegraded in groundwater microcosms to below drinking water standards by aerobic, ethene-oxidizing bacteria (see September abstract). In preparation for implementing field-scale, ethenotrophic co-metabolism (in the Spring of 2005), native populations of ethenotrophs were enumerated in 21 wells. Ethene-oxidizing bacteria were found to range from 400 to 100,000/ml. Interestingly, an inverse relationship was noted between the number of such bacteria and the concentration of vinyl chloride.
November 2004BCI completed its 150th microcosm study in which the reductive dechlorination of chemicals such as TCE and 1,1,1-TCA were evaluated using a variety of electron donors (hydrogen generating food sources). Each microcosm study included a bioaugmented control consisting of BCI's special high-rate dechlorinating strain of Dehalococcoides ethenogenes grown in site groundwater. These tests evaluated groundwaters from 100 different locations throughout the U.S. The results showed that BCI's dechlorinating cultures were 100% adaptable to each groundwater tested, and converted all TCE to ethene.
October 2004BCI announces the availability of an anaerobic, toluene-degrading culture for use in bioaugmentation of toluene contaminated groundwaters. The culture is methanogenic, converting toluene to CO2 and methane.
September 2004Four abstracts were submitted by BCI scientists and their clients for presentation at Battelle’s 2005 conference in Baltimore, MD:
- STIMULATION OF VINYL CHLORIDE BIODEGRADATION IN GROUNDWATER AT LOW CONCENTRATION WITH ETHENE UNDER AEROBIC CONDITIONS
- MONITORING AEROBIC ETHENE BIOSTIMULATION IN A LOW-CONCENTRATION VINYL CHLORIDE PLUME
- BIOREMEDIATION OF CARBON TETRACHLORIDE AND PCE: FIELD RESULTS
- CULTURING AND BIOAUGMENTATION WITH A PROPANOTROPH THAT RAPIDLY DEGRADES 1,4-DIOXANE
August 2004BCI initiates a new research and development effort on the aerobic, co-metabolic degradation of 1,4-Dioxane and related ether compounds. Co-metabolic cultures being investigated from site groundwater include: methanotrophs, ethenotrophs and propanotrophs.
July 2004BCI welcomes its new environmental chemist, Vipin Sumani. Vipin has a Bachelor of Engineering in chemical engineering and a M.S. degree in Environmental Engineering from Texas A&M University (expected November 2004). Vipin’s research focus, under the direction of Dr. Lee Clapp, is the methanotrophic biodegradation of TCE. His thesis title is: “Characterization of Copper Loading: Effect on sMMO Expression in Membrane Attached Methanotrophic Biofilms”.
February 2004BCI's bioaugmentation efforts to date include shipment of its "BCIe" Dehalococcoides culture to 6 field-scale bioremediation projects. Culture has been shipped to 3 sites in Florida, 1 in CA, 1 in TX and 1 in NJ. Mass culturing is planned for an additional 12 locations.
December 2003BCI completed its 75th microcosm test evaluating enhanced natural attenuation of volatile chlorinated compounds in groundwater. The tests were conducted based on BCI's modification of the Air Force RABITT Protocol. One modification now routinely used includes a known Dehalococcoides culture as a positive-control.
September 2003BCI's engineering clients submitted several abstracts listed below for presentation at the Fourth International Battelle Conference "Remediation of Chlorinated and Recalcitrant Compounds" to be held in Monterey CA in May 2004:
August 2003BCI submitted several abstracts listed below for presentation at the Fourth International Battelle Conference "Remediation of Chlorinated and Recalcitrant Compounds" to be held in Monterey CA in May 2004:
July 2003BCI completed its 75th genetic test for Dehalococcoides using PCR analysis. The PCR tests were conducted on groundwater samples from 19 locations in 10 States including Fl, MA, ME, TX, CA, ID, NJ, RI, WA, and TN. 50 % of the sites were PCR positive for Dehalococcoides.
June 2003S.Fogel presented a paper at the National Groundwater Association conference in Baltimore entitled " Ozonophilic Bacterial Degradation of Aliphatic Hydrocarbons Enhanced by Pulsed Ozone Injection". The presentation was made jointly with KV Associates.
May 2003BCI presented a poster at the Battelle Conference in Orlando FL entitled: “EFFECT OF ZERO-VALENT IRON ON GROUNDWATER CONTAINING CHLORINATED SOLVENTS, METHANOGENS AND SULFATE-REDUCERS IN MICROCOSMS”.
April 2003BCI welcomes its new environmental chemist, Mark Rogers. Mark has a B.S degree in chemistry from the University of New Hampshire. He recently returned from the Peace Corps where he served as a natural resources volunteer.
March 2003Professor Martin Polz, MIT Dept Civil Engineering, has joined BCI’s scientific advisory board. Dr Polz provides advice on aspects of microbial ecology that are relevant to BCI’s dechlorinating consortia, and on genetic techniques designed to improve BCI’s PCR and bioaugmentation services.
February 2003BCI evaluated the use of zero valent iron (ZVI) as a potential microbiological amendment and for treatment of high concentrations of chloromethanes in groundwater. Treatability testing found that ZVI selectively degraded carbon tetrachloride without excess production of chloroform. The selective destruction of this compound not only removed a microbial inhibitor from groundwater, but also provided a potential source of hydrogen for the microbial community.
January 2003BCI announces the availability for bioaugmentation of a chlorobenzene-degrading culture.
BCI announces the availability for bioaugmentation of a 1,1,1-TCA-degrading culture.
BCI has developed an enrichment culture capable of anaerobically biodegrading methylene chloride to carbon dioxide. This culture (DCM-1) uses methylene chloride as a sole source of carbon.
October 2002BCI introduces GC analysis for alcohols and glycols allowing detection of compounds such as methanol, ethanol, propanol and propylene glycol, which can all serve as a food sources (electron donors) for dechlorinating bacteria.
September 2002PCR services for detection of Dehalococcoides ethenogenes (DE) in groundwater is inaugurated. Dehalococcoides ethenogenes is the only bacteria able to convert PCE entirely to ethene.
August 2002BCI welcomes its new employee, Scott Douglas. Scott is a graduate of McGill University with a degree in Microbiology and Immunology.
June, 2002BCI's high rate dechlorinating, and ethene-producing culture (BCI-e) was found to be "pathogen-free".
May, 2002BCI personnel, authors on 4 presentations at the Third International Conference on the Remediation of Chlorinated and Recalcitrant Compounds, held May 20-23 in Monterey, California. (Abstracts available, articles to be published in Conference Proceedings in 2002).
1. Optimizing Reductive Dechlorination in a Large-Scale In Situ Bioremediation Site.
2. A Unique Microcosm Method to Assess the Microbial Community at Anaerobic Bioremediation Sites.
3. Full Scale Bioaugmentation for Anaerobic Dechlorination of PCE and DCE
4. Designing In Situ Anaerobic Bioremediation as Primary Remediation for a manufacturing plant
March 24th 2002
The article: MICROCOSM TEST FOR NATURAL ATTENUATION OF CHLORINATED SOLVENTS was published in the Journal of Soil Sediment and Groundwater.
February 28th, 2002
BCI submitted two papers to the Third International Conference on Remediation of Chlorinated and Recalcitrant Compounds (May 20-23, 2002 Monterey, California.
OPTIMIZING REDUCTIVE DECHLORINATION IN A HIGH-SULFATE IN-SITU
Margaret Findlay, Ph.D. (MFindlay@bciLabs.com), Samuel Fogel, Ph.D., Donna Smoler, (Bioremediation Consulting Inc. Watertown, MA, USA) Bradley F. Droy, Ph.D., Frank Manale, and Peikang Jin, Ph.D.,(Toxicological and Environmental Associates, Baton Rouge, LA, USA) Catherine Creber, (The Dow Chemical Company, Sarnia, Ontario, Canada) Gary Klecka, Ph.D., (The Dow Chemical Company, Midland MI, USA)
A UNIQUE MICROCOSM METHOD TO ASSESS THE MICROBIAL COMMUNITY AT
ANAEROBIC BIOREMEDIATION SITE
SSamuel Fogel, Ph.D.(SFogel@bciLabs.com) Margaret Findlay, Ph.D., and Donna Smoler,
(Bioremediation Consulting, Inc., Watertown, MA, USA) Bradley F. Droy, Ph.D., Frank Manale, and Peikang Jin, Ph.D., P.E., (Toxicological & Environmental Associates, Inc., Baton Rouge, LA, USA) Catherine Creber, (The Dow Chemical Company, Sarnia, Ontario Canada) Gary Klecka, Ph.D., (The Dow Chemical Company, Midland, MI, USA)
January 18th, 2002
The BCI launched it's new website at www.bcilabs.com. The new website is growing quickly and will continue to be integrated into our business.
January 1st, 2001
BCI completes the transition to their new offices in Watertown Mass. Click here for photos of the new laboratory and offices.