Although this coating may not persist on the particles in the environment, what is clear is that the effects of chronic dosing and the effects of coating are critical data gaps that should be evaluated. Also completely lacking are more environmentally realistic exposure scenarios, such as ones using natural waters and soils and also multi-species microcosm or mesocosm studies, although such studies are underway. These studies will bring the importance of environmental transformations and indirect ecological impacts into light. It is possible that community or ecosystem level impacts may be more sensitive than individual level effects. Also more chronic and food chain transfer studies should be encouraged to deal with the possible long term effects from, or accumulations of, the likely persistent nanoceria entities. The current available data do not suggest an immediate risk from acute exposures to nanoceria from use as a fuel additive or mechanical/chemical polishing or planarization. However, the data gaps we have discussed should be addressed before a comprehensive ecological risk assessment can be performed for ceria for chronic exposures or for other exposure pathways. This review lays the foundation for such assessments and clearly identifies the areas where research is most critically needed.The Bioremediation, Education, Science and Technology partnership provides a sustainable and contemporary approach to developing new bio-remedial technologies for U. S. Department of Defense priority contaminants while increasing the representation of underrepresented minorities and women in an exciting new bio-technical field. This comprehensive and innovative bio-remediation education program provides under-represented groups with a cross-disciplinary bio-remediation curriculum and financial support, coupled with relevant training experiences at advanced research laboratories and field sites. These programs are designed to provide a stream of highly trained minority and women professionals to meet national environmental needs. The BEST partnership of institutions and participants benefit from a unique central strategy— shared resources across institutional boundaries.
By integrating diffuse resources, BEST forms a specialized “learning institution without walls,” large plastic pots for plants where participants can receive advanced training at any BEST site, and where research capabilities flow freely among the participating institutions. Ongoing faculty and student exchange programs, video taped lectures, the Rotating Scholars program, and the BEST web-site ensure that all participants are empowered with opportunities to excel. The BEST partnership consists of Lawrence Berkeley National Laboratory in Berkeley, Calif., Jackson State University in Jackson, Miss., Ana G. Méndez University System in Puerto Rico, University of Texas at El Paso , University of Southern Mississippi Gulf Coast Research Lab, and University of California at Berkeley . The BEST program contract to the partnership is man-aged by LBNL for the Army Corps of Engineers, Waterways Experiment Station in Vicksburg, Miss. WES manages the contract for the Army Corps of Engineers and is the contracting entity for DoD. The partnership formed by these participating institutions leverages existing institutional resources by strengthening intramural bio-remediation education and research capabilities, and through outreach pro-grams, to disseminate training and scientific enhancement to other Historically Black Colleges and Universities and Minority Institutions . The BEST institutions are focal points for the development and dissemination of cutting-edge research and technology for the bio-remediation of nitro-aro-matic compounds, polycyclic aromatic hydrocarbons and toxic metals. The multidisciplinary BEST partnership strategy creates a flask-to-field solution that develops laboratory research into technology, and technology into field-scale environmental applications required for the cost-effective restoration of damaged environments. This year saw the addition of the University of Southern Mississippi’s Gulf Coast Research Lab and the University of Texas at El Paso as partners in the BEST program. Both institutions provide significant new personnel and training opportunities for the BEST program. The USM Gulf Coast Research Lab investigators’ focus on PAH and heavy metal phytoremediation along shorelines provides an exciting new focus with increased field opportunities for students. The UTEP investigators are focusing on exciting new metal phy-toremediation techniques using desert plants and exciting new techniques to determine risk assessment with PAHs. This year also saw the passage of the program director-ship at LBNL from Dr. Jenny Hunter-Cevera to Dr. Terry C. Hazen in October 1999. Dr. Hunter-Cevera, who has managed the BEST program at LBNL since its inception, will be sorely missed, but her new position as president of the Maryland Biotechnology Institutes may provide increased opportunities for collaboration for the entire BEST program. Dr. Hazen, who specializes in bio-remediation field applications, has demonstrated or deployed bio-remediation technologies at more than 50 sites around the United States and in Europe. He has five patents in bio-remediation technologies that are licensed by more than 40 companies in the U.S. and Europe.
During the past year, the BEST program has provided minority research training for five high school students, 74 undergraduates, 32 graduate students, three post-doctoral fellows and 10 faculty. Students and fac-ulty investigators have given 43 presentations on BEST research at scientific meetings and have published 17 scientific papers. The program produced a full color brochure and flyers in 1999 for use in recruiting more students, and also sponsored 32 lecture/seminars on bio-remediation. Fourteen videotapes of BEST seminars at LBNL/UCB were distributed to the partner institutions. The BEST program also sponsored a phytoremediation workshop for BEST investigators and students that was attended by more than 60 participants. Additional workshops are planned for the coming year. In this report, the research is organized by subject area, and two-page briefs are presented for each of 28 BEST projects. The projects presented provide a good representation of the state-of-the-science research being done with students in the BEST program – the best of BEST.Over the next 75 years, the U.S. government will undertake what has been called the largest civil works project in world history to restore the environment damaged by previous activities at federal sites, e.g., Department of Defense military bases and Department of Energy nuclear facilities. Legislative action, resulting from concern over the accumulating hazards, has mandated pollution control measures and environmental restoration of hazardous waste at all sites. Estimates of total cleanup costs range from $230 billion to more than half a trillion dollars. Given the trend of diminishing budgets throughout the federal government, future generations could inherit both an environmental and budgetary disaster. The imprecision of the cost estimates results from the lack of knowledge of how “clean” the contaminated sites will need to be. Some of the environmental damage is permanent—cleanup technologies either do not exist or are incapable of remediating the contamination. For DoD bases being closed by the Base Realignment and Closure Program, all toxic sites must be remediated before the site is returned to public use. The projected costs of site restoration using existing technologies are staggering: the estimated cleanup cost is at least $24.5 billion for the 7,313 identified U.S. sites . The pollutants at these sites include chlorinated hydrocarbons, metals, petroleum products, explosives, mixed waste and other organics. DOE also has substantial remediation costs—estimated to be from $90 billion to $200 billion . The domestic private sector presents yet another huge set of remediation problems, dwarfed only by the international problems in Eastern Europe and Russia . There is clearly a need for new cost-effective treatment technologies. Bio-remediation, the use of microor-ganisms to detoxify hazardous waste, promises to provide economical and ecologically sound clean-up strategies. An Office of Technology Assessment analysis concluded that the U.S. does not possess a sufficient pool of qualified environmental professionals, i.e.,blueberry pot the trained scientific personnel required to support this rapidly developing multi-disciplinary field. In response to these national environmental needs, the Bio-remediation Education, Science and Technology Program, funded by DoD, was established in 1996. In a few short years, BEST has pioneered a new and successful model for environmental science and education. This partnership has a highly integrated programmatic focus on the scientific and workforce needs of DoD. Since the inception of the BEST program, a significant number of major milestones and deliverables have been achieved. They are described below. The BEST program has made these dramatic accomplishments by using an approach that combines a training-education element with an integrated research project, described later in this introduction.DoD sites throughout the United States contain highly contaminated soils, groundwater and sediments. These properties pose direct and indirect exposure hazards to humans and wildlife.
Conventional remedial solutions for contaminated soils and sediments or groundwater are slow and expensive, increase inputs to hazardous waste disposal sites, and can increase human exposure to contaminants. Bio-remediation — the use of microo ganisms to destroy hazardous contaminants or to con-vert them to harmless forms — is an emerging treatment technology that can in many instances restore contaminated environments more quickly, at lower cost and at lower human risk than alternative remediation technologies. Bio-remediation can operate in either an in situ mode where contaminants are treated in place, or in an ex situ mode where contaminants are removed from a contaminated zone for treatment . In situ bio-remediation can be used when excavation is impractical — under buildings, highways, runways, etc. In situ bio-remediation can simultaneously treat soil and groundwater in one step, without the generation of hazardous waste products. In situ contaminant degradation can be achieved by either intrinsic or enhanced bio-remediation. Intrinsic bio-remediation exploits the innate capabilities of indigenous micro-bial communities to degrade pollutants. Enhanced bio-remediation seeks to accelerate in situ microbial activity by isolating and controlling the contaminated site so that the microbial environment can be purposely manipulated to correct nutritional or gas phase limitations. Ex situ treatment seeks to further control the remedial environment by placing the contaminants in an engineered treatment system. Phytore mediation, a process in which plants and asso-ciated microbial communities are used for contaminant bio-degradation or bio-immobilization, is an important and rapidly developing mode of bio-remediation. To realize the full potential benefits of plant and microbial treatment systems at DoD sites, these bio-technologies must be developed and optimized for remediation of DoD priority contaminants by an expanded pool of qualified professionals. It was in response to these DoD environmental needs that the BEST partnership of institutions was established.In order to determine whether plants can stimulate the degradation of PAHs in soil, plant species found in literature on phytoremediation of metal-contaminated sites were selected to measure the removal of PAHs in artificially contaminated soil over a period of 62 days. The plant species used for this experiment were alfalfa , barley , tall fescue and orchard grass . The PAHs were phenanthrene and anthracene, in a mixture of 600 ppm each. As shown in Figures 1 and 2, phenanthrene and anthracene were removed from the soils with plants after 62 days. More than 98% of the phenanthrene was removed during that period while the anthracene removal was found to be between 70 and 90%. The results suggest that the rate of disappearance of phenanthrene in soil was greater than anthracene under the same conditions. From the results, it is also indicated that the disappearance of PAHs in soil depends on the bio-availability of the compounds. Because phenanthrene is approximately 10 times more soluble in water than anthracene, it was expected to be more readily available to microbial degradation than anthracene. Plant-assisted degradation of PAHs is thought to be more effective on PAHs with a higher number of rings and higher molecular weights, such as benzopyrene. Anthracene removal in the soil planted with alfalfa was greater than in the soil without plants, while all the other plants have minimal to no effect on anthracene removal compared to the control soil. Phenanthrene was removed to a greater extent in the soil with alfalfa and tall fescue compared to the control without plants . However, both barley and orchard grass showed no effects of the removal of phenanthrene during that period when compared to the soil without plants. Overall, plants had minimum effect on phenanthrene degradation while anthracene degradation was more dependent on plant species. In order to determine the effect of PAH degradation by plants on bacterial numbers in soil, bacteria were counted in soil during the course of the experiment.Parathion is a widely used organophosphate insecticide which can cause adverse neurological effects if ingested or after dermal exposure. No single microor-ganism has been isolated that is capable of completely mineralizing parathion and its metabolites. Hydrolysis of parathion significantly lowers the toxicity of the parent compound, but results in the formation of a toxic intermediate, the nitroaromatic compound p-nitrophenol.