Brief Summary of Minutes of Annual Meeting

See http://s-1022.okstate.edu for minutes to annual meeting.

Objective 1. Researchers with ongoing collaborations between the University of Georgia and Virginia Tech has focused on possible solutions to reducing this background organic matter fluorescence. First, organic matter fluorescence in environmental waters has a broadband, featureless emission spectrum, whereas the emission spectra of optical brighteners are in the 415- to 445-nm range. Therefore, one solution may be to restrict the emission filter in the fluorometer to this narrow wavelength. Second, optical brighteners photodegrade quickly (half life, several hours) when exposed to sunlight. Therefore, another solution may be to irradiate environmental water with UV light to determine if photodecay rates between optical brighteners and organic matter differ. Therefore, a series of experiments was conducted to determine the effect of: a) changing the normal 400 to 610-nm emission filter in the fluorometer to a 436-nm emission filter, and b) exposing water samples to UV light to determine if photodecay rates of optical brighteners and organic matter differed. In addition, several other variables were tested that might affect UV exposure experiments: shaking the sample, seawater versus freshwater, and UV light intensity. The findings suggest two major changes to the fluorometry should improve its usefulness as a source tracking method. First, changing the emission filter in the fluorometer from a 410 to 600-nm filter to a 436-nm emission filter should reduce background fluorescence from organic matter. The 436-nm filter significantly reduced fluorescence from Suwannee River Natural Organic Matter. However, this reduction worked well only at lower concentrations of organic matter (d40 mg L-1); higher concentrations of organic matter suppressed fluorescence. Therefore, this concentration seems like a reasonable limit for fluorometry. However, this limit requires that one know the concentration of total organic carbon in the water, and therefore water needs to be tested to know this concentration. Second, exposing the water sample to UV light for 30 minutes photodegraded optical brighteners. This photodegradation is consistent with studies of optical brighteners in natural and monochromatic light in water with and without dissolved natural organic matter (Kramer et al., 1996). Although organic matter also degraded upon exposure to UV light, the rate of photodegradation for optical brightener was significantly greater than the rate for organic matter after the first 30 minutes. Shaking the sample or increasing the UV intensity did not affect the results significantly. Although the fluorometric method appeared to work equally well with synthetic seawater as it did with distilled water, this result was only obtained with the 436-nm emission filter. It was not possible to calibrate the fluorometer with seawater using the 410 to 600-nm emission filter. The most likely problem with seawater is that it contains a relatively high concentration of magnesium, which enhances fluorescence, most likely by adding cross-links to organic matter structure. Objective 2. Research for the past few months has focused on antibiotic resistance and the stability of antibiotic resistance genes in fecal indicator bacteria. Research in Indiana includes the evaluation of E. coli isolates from the environment for EHEC virulence genes. Of the 1700 isolates from over 144 animals, 46% of the isolates with toxin genes were cytotoxic. Additionally, the influence of diet and perturbation on the human gut microbial community structure has been evaluated. Results indicate the community DNA fingerprint is of each subject is unique to each subject. When diets are the same the communities become stable. Research in New York involves looking at dairy manure applied to soil from farms where monensin is used as a feed additive for calves. They have collected soils and recovered antibiotic resistant bacteria from the soil samples. Several methods to evaluate bacterial community composition have been used. These methods include DGGE, T-RFLP, ARISA, and 2D-PAGE. Use of 2D-PAGE provides the greatest level of discrimination between communities. Findings suggest that target DNA for amplification and analysis must meet specific criteria; amplicons must have a large range of size and polymorphisms in G+C content. Ongoing collaborations with researchers from Arkansas and Okalahoma includes the evaluation of antibiotic resistance in fecal indicator bacteria in stream waters in Arkansas (Mud Creek and Spring Creek) and Tahlequah Creek in Oklahoma. This project is in response to USGS findings of the antibiotics erythromycin, sulfadimethoxine, sulfamethoxazole, tylosin, trimethoprim, ciprofloxacin, and ofloxacin - at very low levels in the creeks in Arkansas. Water samples were collected from Mud Creek upstream from the wastewater treatment facility and at a 1st downstream and 2nd downstream position. Preliminary data for ampicillin, tetracycline and ofloxacin suggest that there is higher resistance to the antibiotics at the first downstream location and that resistance decreases at the second downstream location. Researchers in Alabama have conducted a bacterial source tracking study using a library based rep-PCR approach. Current library is small containing 414 unique E. coli DNA fingerprints. Eighteen percent of the E. coli isolates from water samples matched a human signature. The presence of the human signature was confirmed by LC-MS analysis of chemical compounds known to be used by humans. Evaluation of antibiotic resistance profiles of indicator bacteria in swine manure before and after manure management and the development of antibiotic resistance in nursery pigs at different stages of development have been conducted in North Carolina. Preliminary results suggest that antibiotic resistance is not confined to one particular stage of development of the pig, is not confined to one particular stage of livestock production, and the indicator bacteria that persist after manure management continue to exhibit antibiotic resistance. In West Virginia the patterns of antibiotic resistance in fecal bacterial isolates obtained from organic and conventionally raised chickens and sheep. They also compare rep-PCR fingerprints obtained from these isolates.

Accepted Full length Articles (Refereed Journals): Hassan G., R. Reneau, C. Hagedorn and M. Saluta. 2005. Modeling water flow behavior where highly treated effluent is applied to soil at varying rates and dosing frequencies. Soil Sci. 170 (9): 692-706. McDonald, J. L., P. G. Hartel, L. C. Gentit, K. W. Gates, K. Rodgers, J. A. Fisher, K. A. Smith, K. A. Payne, and C. N. Belcher. 2006. Identifying sources of fecal contamination inexpensively with targeted sampling and bacterial source tracking. J. Environ. Qual. 35:889-897. McMullen, J., O.O. Fasina, C.W. Wood and Y. Feng. 2005. Storage and handling characteristics of pellets from poultry litter. Appl. Eng. Agric. 21:645-651. Jenkins, M.B., Endale, D.M., Schomberg, H.H., and Sharpe, R.R. 2006. Fecal bacteria and sex hormones in soil and runoff from cropped watersheds amended with poultry litter. Science of the Total Environment 358:164-177. Soupir M., S. Mostaghimi, G. Yagow, C. Hagedorn and D. Vaughan. 2005. Release and transport of bacteria from livestock manure applied to pasturelands. Water, Air, and Soil Pollution. 169: 125-136. URL: http://dx.doi.org/10.1007/s11270-005-1808-2. Accepted Full Length Articles (Book Chapters): Feng, Y. 200X. Soil Microbiology. In: Encyclopedia of Soil Science, W. Chesworth (ed). Springer Publishing Company, New York, NY. (in press) Keeling, W. G., C. Hagedorn, and B. A. Wiggins, and K. Porter. 2005. Bacterial Source Tracking: Concept and Application to TMDL. In "Total Maximum Daily Load: Approaches and Challenges," (T. Younos, Ed.). PennWell Books, Tulsa, OK. URL: http://store.yahoo.com/pennwell/totmaxdaillo2.html. In Print Abstracts: Colley, Z., Fasina, O.O., Brasnby, D., Wood, C.W., Feng, Y. 2005. Compaction behavior of poultry litter and switchgrass. Paper No. 05-6053. ASAE International Meeting, Tampa, FL. July 17thto 20th. Dickerson, J., C. Hagedorn, A. Hassall, and S. Herbein. 2005. An evaluation of beach remediation in Virginia using four bacterial source tracking methods. 105th Annual Meeting of the American Society for Microbiology, Orlando, FL. ASM Abstracts. Feng, Y., R. U. Wijesinghe and C.W. Wood. 2005. Microbial source tracking as a component of TMDL development. Alabama Water Resources Conference and Symposium. Orange Beach, Alabama. Hagedorn, C., G. Touchton, B. Crozier, A. Hassall, and J. Dickerson. 2005. Increasing confidence and reliability of library-dependent microbial source tracking methods. 105th Annual Meeting of the American Society for Microbiology, Orlando, FL. ASM Abstracts. Hartel, P. G., K. Rodgers, G. L. Moody, S. N. J. Hemmings, J. A. Fisher, J. L. McDonald, and C. N. Belcher. 2006. Combining targeted sampling and fluorometry for bacterial source tracking of a freshwater creek. American Society for Microbiology Annual Meeting, May 21-25, Orlando, FL. Hassall A., C. Hagedorn, M. Saluta, J. Dickerson and S. Herbein. 2005. Microbial source tracking in Virginia's waterways. Annual Meeting of the American Society of Agronomy, Soil Science Society of America, and Crop Science Society of America, Salt Lake City, UT. ASA-CSSA-SSSA Abstracts. McDonald, J. L., P. G. Hartel, L. C. Gentit, C. N. Belcher, K. W. Gates, K. Rodgers, J. A. Fisher, K. A. Smith, and K. A. Payne. 2006. Identifying sources of fecal contamination inexpensively with targeted sampling and bacterial source tracking. American Society for Microbiology Annual Meeting, May 21-25, Orlando, FL. Phyars, A.A., L. Qian, and A.K. Graves. 2006. Antibiotic Resistance Profiles of Escherichia coli and Enterococcus sp. Isolated from Nursery Pigs at Different Stages of Development. Sixth annual Arizona More Graduate Education at Mountain States Alliance., April 21, Tempe, AZ. Wijesinghe, R.U., Y.Feng, D.S. Stoeckel, C.W. Wood. 2005. Comparison of rep-PCR DNA fingerprints of Escherichia coli isolated from multiple sources. The 105th General Meeting Abstracts [CD-ROM]. American society for Microbiology, Washington, DC. Wijesinghe, R.U., Y. Feng, C.W. Wood and J.N. Shaw. 2005. Genetic variability of rep-PCR DNA fingerprints of Escherichia coli isolated from the Catoma Creek watershed. Annual Meetings Abstracts [CD-ROM]. ASA, CSSA, SSSA, Madison, WI. Non-Refereed Publications: Dickerson J., C. Hagedorn, A. Hassall and M. Saluta. 2005. Fluorometric Detection of Optical Brighteners as an Indicator of Human Sources of Water Pollution. Part I. Description and Detection of Optical Brighteners. Crop and Soil Environmental News, November 2005. URL: http://www.ext.vt.edu/news/periodicals/cses/2005-11/part1.html. Dickerson J., C. Hagedorn, A. Hassall and M. Saluta. 2005. Fluorometric Detection of Optical Brighteners as an Indicator of Human Sources of Water Pollution. Part II. Development as a Source Tracking Methodology in Open Waters. Crop and Soil Environmental News, November 2005. URL: http://www.ext.vt.edu/news/periodicals/cses/2005-11/part2.html. Proceedings: None Experiment Stations Bulletins: None Extension Bulletins: Hagedorn C., B. Benham and S. Zeckoski. 2005. Microbial Source Tracking and the TMDL Process. URL: http://www.ext.vt.edu/pubs/bse/442-554/442-554.pdf. Theses: M.S.: Touchton, Gregory. 2005. Microbial Source Tracking in a Mixed Use Watershed in Northern Virginia. Virginia Tech, Blacksburg VA. M.S.: Jones, C.M. 2006. Microbial community analysis using two dimensional electrophoresis of bacterial ribosomal internal transcribed spacer regions  methodology and application. Cornell University, Ithaca, NY M.S.: Wijesinghe. 2005. A molecular approach to determine the origin of fecal bacteria in the Catoma Creek watershed. Auburn University, Auburn, AL. Newspaper, Magazines, Newsletters, etc.: Hagedorn C. 2005. Bacterial Source Tracking in Support of TMDLs. Federal Water Quality Association Newsletter, Vol. 31(2), p.5. Hagedorn C., M. Saluta, A. Hassall and J. Dickerson. 2005. Fluorometric Detection of Optical Brighteners as an Indicator of Human Sources of Water Pollution: Development as a Source Tracking Methodology. Environmental Detection News, Joint Issue 3/4(II), 1-12. URL: http://www.cddc.vt.edu/host/edn/index.html. Hagedorn C. 2005. Beachgoers Want Answers. Article published in The Free Lance Star (newspaper), Fredericksburg, VA.URL: http://fredericksburg.com/News/FLS/2005/062005/06182005/107237.asp Hagedorn C. 2005. Pollution Findings Prompt Groups to Clean Streams. Article published in the Winchester Star (newspaper), Winchester, VA. URL: http://www.winchesterstar.com/TheWinchesterStar/050912/Area_pollution.asp. Hagedorn C. August 12, 2005. Scat Squad: Finding Pollution's Causes. The 14 minute story aired on National Public Radio (NPR), "All Things Considered." URL: http://www.npr.org/templates/story/story.php?storyId=4798461