| Funding | National Science Foundation (NSF) |
| Period | April 15, 2008 - March 31, 2011 |
| Description | Our basic hypothesis is that polybrominated diphenyl ethers (PBDEs), which have accumulated in the environment over the past four decades, have debrominated in the sediments of heavily contaminated water bodies. The overall objective of this work is to investigate the current extent, time scale, congener pattern variation, and influencing factors of in situ PBDE debromination in the sediments of natural waters. This project takes advantage of naturally generated sediment profiles, and features a comprehensive multi-disciplinary approach using state-of-the-art tools in chemistry, microbiology and mathematical modeling. |
| Researchers | An Li, Karl J. Rockne, Erik R. Christensen, Hua Wei, Azivy Aziz |
| Documents | not available at this time |
| Funding | National Institute of Health (NIH) National Institute of Environmental Health Sciences |
| Period | April 1, 2007 - March 31, 2009 |
| Description | We are developing a laboratory procedure for the analysis of polybrominated diphenyl ethers (PBDEs) in human placental tissues. The work will include three tasks: analytical method development and validation, examination on the integrity of stored samples in two sample banks, and a preliminary investigation on the levels of PBDEs in human from different regions of the world. The result of this work will be useful in future comprehensive studies on prenatal exposure of human to PBDEs. |
| Researchers | An Li, Priyanthi Shyamalee Dassanayake |
| Documents | not available at this time |
| Funding | US Environmental Protection Agency (USEPA) Great Lakes National Program Office |
| Period | August 1, 2007 - July 31, 2010 |
| Description | We are investigating the spatial distribution and input chronology of several halogenated flame retardants (XFRs) in the Great Lake. The targeted chemicals will include dechlorane plus (DP), decabromodiphenylethane (DBDPE), 2,2,4,4,5,5-hexabromobiphenyl (BB153), 1,2-Bis(2,4,6-tribromophenoxy)ethane (TBE), 2,3,4,5,6-pentabromoethylbenzene (PEB), and others. Some of these XFR are very recently detected in the environment, with little information available. Sediment cores have been collected, sectioned, characterized and dated for deposition years. Chemical analysis will start after laboratory procedure development and validation. Come back here to see our progress! |
| Researchers | An Li, Ruiqiang Yang, Hua Wei |
| Documents | photos, videos (coming soon) |
| Funding | Illinois Waste Management and Research Center |
| Period | September 1, 2006 - June 30, 2008 |
| Description | This project focuses on the reductive debromination potential of PBDEs in sludge. The field phase of this research is comprised of detailed analysis of PBDEs throughout the sludge treatment train. Laboratory studies will focus on determining the potential and rate of reductive debromination in controlled studies using a variety of inhibitors and stimulation with potential ˇ°haloprimers.ˇ± A priori, we hypothesize that PBDEs will have a greater dehalogenation potential than PCBs due to the weaker Br-C bond. We also hypothesize that BDE-209 will reductively debrominate to lower congeners, thus leading to an increase in bioavailability and toxicity. Finally, debromination potential and kinetic data obtained will be used to predict BDE dynamics in various digester formulations using a model developed as part of this work. |
| Researchers | Karl Rockne, An Li, Jayashree Jayaraj |
| Documents | not available at this time |
| Funding | US Environmental Protection Agency Region 5 Air and Radiation Division |
| Period | October 1, 2001 - December 31, 2005 |
| Description | Sediment cores were collected from 16 locations in the five Laurentian Great Lakes, and each was analyzed for PBDEs and PCBs. The total accumulation of PBDEs in the sediments was estimated to be approximately 97 tonnes around year 2002. The inventories of S9BDEs and major individual PBDE congeners show strong dependence on the latitude of sampling sites. From the 1970s to 2002, the increases in PBDE input flux to the sediments are exponential at all locations. The correlations between the concentrations of PBDEs in surface sediments and latitude are strengthened by normalization based on sediment contents of the organic matter or organic carbon, but not soot carbon. The three independent variables - year of deposition, latitude, and organic matter content of the sediments - account for about 70% of the variations in PBDE concentrations or fluxes in the Great Lakes sediments. |
| Researchers | An Li, Karl J. Rockne, Neil C. Sturchio, Wenlu Song, Justin C. Ford, David R, Buckley, William J. Mills. |
| Documents | Proposal, Final Report, photos (coming soon) |
| Funding | USEPA STAR Grant via the Mickey Leland National Urban Air Toxics Research Center |
| Period | August 1, 1999 - December 31, 2003 |
| Description | Indoor and outdoor air samples at ten non-smoker homes in the Chicago area were concurrently collected once per month for a 14-month period. Total PAHs ranged from 13 to 2,454 ng m-3 in the indoor air and from 13 to 1,865 ng m-3 in the outdoor air. Light PAHs with MW<=202 behave differently from the heavy ones (MW>=228). Variations among seasons were significant for indoor light-PAHs, and outdoor heavy-PAHs were significantly higher in the fall and winter seasons than in the summer. The correlations of indoor and outdoor concentrations appear to be weak for light PAHs, but reasonably strong for heavy PAHs. The indoor level of total-PAHs tends to be higher in older houses, and the surrounding industrial pollution was found to impact outdoor heavy-PAHs. For light PAHs indoors, the impact of house characteristics and indoor activities tends to be greater than the influence of the penetrating outdoor air. |
| Researchers | An Li, Peter A. Scheff, Richard A. Wadden, Todd M. Schoonover, Qimeng Zou, Felice Norlock |
| Document | Proposal, Final Report |