Progress 10/31/00 to 09/30/05
Outputs
The overall goal of Dr. Charles' research projects was to determine the impact of anthropogenic organic pollutants on human health. The projects fell into three board categories; 1) development of new analytical techniques for emerging chemicals of concern, 2) determination of sources and environmental fate of both anthropogenic and naturally-occurring chemicals, and 3) assessing the health impacts of these chemicals of concern. The first research area was development of novel analytical methods for emerging chemicals of concern. One such research project was developing analytical methods for the detection of acrolein, the greatest non-cancer organic hazardous air pollutant in California. A second research project was refining chemical analysis of atmospheric particulate matter with an emphasis on acids and carbonyls. Lastly, analytical methods were developed to determine PCBs metabolites in human blood samples as an indicator of PCB exposure. The second area of
research was the determination of the sources and fate of environmental pollutants. One of the main research projects was determining organic emissions from passenger cars and diesel trucks to estimate their relative contribution to air pollution. Additional projects included determining the emissions of brominated fire-retardants near suspected sources and the contribution of biogenic organic chemicals to atmospheric particulate matter formation. The last research focus was determining the health impacts of contaminants in people, which is exemplified by two projects. The first was determining PCB metabolites in human blood samples and then using epidemiological data to correlate PCBs exposure to reported health problems. The second project was determined human exposure to acrolein and other toxic carbonyls in domestic, occupational and environmental exposure situations.
Impacts
The objective of the research was to better understand the sources and fate of toxic anthropogenic pollutants that affect human health. Only by understanding the source and fate of these pollutants can effective mitigation measures be formulated to reduce human exposure and alleviate the toxic effects. This research determined both chemical emission rates and ambient concentration data to assess the occupational and domestic exposure to toxic chemicals.
Publications
- No publications reported this period
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Progress 01/01/04 to 12/31/04
Outputs
The three foci of research are: 1) determining the health effects of trace organic contaminants, 2) determining the sources and environmental fate of anthropogenic or naturally organic compounds, and 3) development of analytical methods to measure trace organic pollutants in the environment. The first research focus of determining the health impacts of contaminants in people is exemplified by two projects, the first of which is currently determining PCB metabolites in human blood samples while second is determining acrolein, a toxic air contaminant, and other small carbonyl species in exposed populations such as tollbooth attendants. The second research area of determining sources and fate of organic compounds has three research projects underway. The first is determining organic emissions, with a focus on acids and carbonyls, from passenger cars and diesel trucks to better determine the contribution of these sources to ambient air pollution. The second project is
determining the role of biogenic organic chemicals, such as isoprene and pinene, on aerosol formation by tracking the conversion of these gaseous chemicals into oxidized acids and carbonyls. This project is a collaborative project with Dr. Goldstein at the University of California, Berkeley. The last project, which is nearing completion, is determining the source strength of polybrominated diphenyls (PBDEs), a class of fire retardants, from electronics recycling and automotive dismantling facilities where high concentrations of PBDEs were expected. The last research area is the development of new analytical methods for the detection of trace quantities of organic pollutants. Research in this area is currently focused on improving analytical methods for the detection of acrolein in ambient air samples as well as determining heavy polycyclic aromatic hydrocarbons. With molecular weights greater than 300 amu, in source emission samples and ambient aerosols.
Impacts
The ultimate impact of the research conducted in our laboratory is to better understand the sources and fate of toxic atmospheric pollutants that affect human health. Only by understanding the source and the fate of these pollutants can effective mitigation measures be formulated to reduce human exposure, and hence toxic impacts of these chemicals. For example, if most human exposure to polybrominated diphenyl ethers occurs indoors from product use, then mitigation measures should focus on the indoor exposure route. Similarly, comparing the profiles of chemicals emitted from passenger cars and heavy-duty diesel trucks gives an indication of which vehicles contribute the most pollution to the atmosphere, and thus where mitigation measures would be most effective. The vehicle emission profiles may also provide a tracer such that the presence of the tracer chemicals in ambient particulate matter may be linked to a particular vehicle type. Lastly, acrolein is one of the
few organic air pollutants that have correlated with human health impacts in epidemiology studies, yet very little is known about this chemical due to analytical difficulties in detecting it in ambient atmospheric samples. In this case, we are developing analytical methods to determine acrolein in ambient samples and then apply these methods to determine the exposure of people in occupations that may be subject the elevated concentrations, and hence elevated risk of toxic effects, of acrolein.
Publications
- Rogers, E.; Petreas, M.; Park, J-S.; Zhao, G.; Charles, M.J. Evaluation of four capillary columns for the analysis of organochlorine pesticides, polychlorinated biphenyls, and polybrominated diphenyl ethers in human serum for epidemiologic studies. Journal of Chromatography B, 813(2004): 269-285.
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Progress 01/01/03 to 12/31/03
Outputs
The three foci of research conducted in the laboratory are: 1) health effects of trace organic contaminants, 2) environmental fate and distribution of anthropogenically or naturally emitted organic contaminants, and 3) development of methods to measure trace organic pollutants in the environment. The organic contaminants chosen to study either directly or indirectly affect the integrity of the environment or human health. In support of epidemiological studies that investigate human health exposures to trace organic contaminants, our laboratory measures organohalogen persistent organic pollutants in biological matrices (e.g. human serum). In this year, we began a project to quantify body burden levels of metabolites of polychlorinated biphenyls (PCBs) (hydroxylated PCB and methyl sulfone PCBs) in a population in Slovakia exposed to high levels of PCBs. Over the past year, work was conducted to adapt the methods to measure these metabolites in our laboratory. We also
completed a study in collaboration with the Hazardous Materials Laboratory, California Department of Environmental Protection. To gain insight into the generation of anthropogenic pollutants, we sampled diesel and gasoline motor vehicle emissions in a project whose aim is to speciate the polar oxygenated organics in these emissions to ascertain if there are compounds unique to the diesel emissions that can be used for source apportionment. We also began work to sample polybrominated diphenyl ethers in indoor and ambient air.
Impacts
The body burden of BDEs in California women has increased for non-detectable Tlevels to among the highest levels in the world over the past forty years. Lower levels of BDEs in European populations likely reflect less usage of BDE flame retardants in Europe. High levels of BDEs in women residing in the SF Bay area may be due to the stricter regulations that California imposes on fire safety than other States and Europe. While diet is presumed to be the primary source of exposure for PCBs and BDEs, the finding that tge BDEs are not well correlated with PCBs in the California population invokes uncertainty regarding this hypothesis. The finding of high levels of BDEs in women in California led the State of California to enact legislation to ban the distribution of products containing technical mixtures of pentaBDEs and octaBDEs ban in California beginning in Year 2008. Data forthcoming from sampling of BDEs in indoor and outdoor air will be used evaluate current
exposures. Forthcoming data on molecular speciation of diesel and gasoline emissions will be used to identify a compound unique to diesel particulate matter. The discovery of such a compound is critical to understand the impact of regulations to control diesel particulate matter and quantify human exposures.
Publications
- Petreas, M., She, J., Brown, R., Winkler, J., Rogers, E., Zhao, G., Windham, G., Bhatia, R. and Charles, M. J. 2003. High body burdens of 2,2',4,4'-tetrabrominated diphenyl ether (BDE-47) in California Women, EHP. 111(9):1175-1179.
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Progress 01/01/02 to 12/31/02
Outputs
The three foci of research conducted in the laboratory are: 1) health effects of trace organic contaminants; 2) environmental fate and distribution of anthropogenically or naturally emitted organic contaminants, and 3) development of methods to measure trace organic pollutants in the environment. The organic contaminants chosen to study either directly or indirectly affect the integrity of the environment or human health. To this end, the research complies with the mission of Agricultural and Experiment Station research because maintaining the integrity of the environment is critical to preserve agricultural resources and to promote agricultural growth within the State of California, and the fate and distribution of anthropogenic and biogenic pollutants in the environment is exposure to humans through food (e.g., diet) or inhalation that effects human resources. In support of epidemiological studies that investigate human health exposures to trace organic
contaminants, our laboratory measures organohalogen persistent organic pollutants in biological matrices (e.g., human serum). One study completed, discussed in the previous report, measured chlorinated pesticides and polychlorinated biphenyls (PCBs) in serum from a cohort of pregnant women residing in the San Francisco Bay area in the 1960's, a time when PCB exposures were at their highest, to gain insight into neurodevelopment effects on the children. The results of the study were used to compare PCBs across studies of human neurodevelopment. Through a collaborative publication with other highly visible authors in the area, we contributed to the state-of-knowledge regarding the affect of PCBs on human neurodevelopment. To gain insight into the impact of anthropogenic and biogenic hydrocarbon emissions on tropospheric ozone formation, we developed a method that utilizes a mist chamber to sample the highly polar oxidation products which are multifunctional carbonyls containing -OH and
-COOH functionalities on the molecule. Using this method, we identified oxidation products of isoprene and 2-methyl-3-butenol in the ambient atmospheric environment, which were hypothesized to exist but never demonstrated to exist in air. The method developed in our laboratory to measure carbonyls in air was employed to gain insight into the concentration and distribution of acrolein, a hazardous air pollutant that may pose the highest non-cancer risk to populations in California, and elsewhere in the United States. Previous method utilized to measure acrolein in the ambient environment has severe limitations, which do not exist in our method. We used the method to measure acrolein at the Oakland-San Francisco Bay Bridge Toll Plaza. The results indicate that acrolein can be present at levels that are hazardous to human health.
Impacts
In the comparison of the median concentration of PCB 153 in the 10 studies from a variety of populations in the United States, Canada, Holland and Germany, the distribution of PCB exposure in the majority of studies overlapped substantially. The exposures in our study and another U.S. study were about one third of those in the four earlier U.S. studies or recent Dutch, German, and Northern Quebec studies. The results will facilitate a direct comparison of the findings on PCBs and neurodevelopment when they are published for all 10 studies. Models formulated to predict tropospheric ozone formation are primarily based on the results of laboratory studies that measure the parent hydrocarbons and their oxidation products. The models are fraught with uncertainties. Contributions to these uncertainties are the performance of experiments under conditions that are not representative of the real environment. The result of field studies conducted contributes to the validation
of the laboratory experiments and information used to formulate the models. The end result will be improved capabilities to reduce tropospheric ozone and the deleterious effects on plants and human health.
Publications
- Matthew P. Longnecker, Mary S. Wolff, Beth C. Gladen, John W. Brock, Philippe Grandjean, Joseph L. Jacobson, Susan A. Korrick, Walter J. Rogan, Nynke Weisglas-Kuperus, Irva Hertz-Picciotto, Pierre Ayotte, Paul Stewart, Gerhard Winneke, M. Judith Charles, Sandra W. Jacobson, Eric Dewailly, E. Rudy Boersma, Larisa M. Altshul, Birger Heinzow, James J. Pagano, Allan A. Jensen. 2003. Comparison of polychlorinated biphenyl (PCB) levels across studies of human neurodevelopment. EHP, 111(1), 65-70.
- Destaillats, H., Spaulding, R. S., Charles, M. J. 2002. Ambient Air Measurement of Acrolein and Other Carbonyls at the Oakland-San Francisco Bay Bridge Toll Plaza. Environ. Sci. & Technol., 36 (10):2227-2235.
- Spaulding, R.S., Charles, M. J. 2002. A Comparison of Extraction and Silylation Methods for Pentafluorobenzyl Derivatives of Multi-functional Carbonyls, Anal. and Bioanal. Chem., 372:808-816.
- Spaulding, R. S., Tuazon, E. C., Lashley, M., Charles, M. J. 2002. Ion Trap Mass Spectrometry Affords Advances in the Analytical and Atmospheric Chemistry of 2-hydroxy-2-methylpropanal, a Proposed Photo-oxidation Product of 2-methyl-3-buten-2-ol. JASMS, 13:530-542.
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Progress 01/01/01 to 12/31/01
Outputs
We completed the measurements for the epidemiological study that is investigating health effects of polychlorinated (PCBs) in a cohort of pregnant women in the 1960's. The data are being analyzed to determine any health effects in children born to the mothers by Dr. Hertz-Picciotto, an epidemiologist who recently moved from the University of North Carolina to the University of California, Davis. The results of the project thus far are the development of a standardized approach to report organochlorines that is based on a reproducible method to determine the limit of quantification (LQ). We illustrated the approach by using the data in this study. We also investigated predictors of serum levels of eleven individual PCB congeners, total PCB's, p,p'- DDE, o,p'-DDT, p,p'-DDT, and their sum, and heptachlor epoxide in the cohort of pregnant women . We found that as compared with today's populations in western countries, the organochlorine levels are high, as they reflect
recent and ongoing exposure. In addition, we discovered that serum concentrations of several individual PCB congeners, particularly highly chlorinated ones, as well as the sum of PCB's, increased with age. Non-white women had higher concentrations of DDT and its metabolites, as well as of the higher chlorination PCB's We are continuing to develop methods to measure polar and oxygenated organics in aerosols to gain insight into the role that such compounds play in tropospheric ozone formation, phootooxidation reaction on particles as they are transported in the environment, and molecular speciation of fine particulate matter. Thus far, we developed a method capable of measuring water-soluble organics with Herny's law constants greater than 103 M atm-1 and tested the method by sampling photooxidation products of the biogenic hydrocarbons isoprene and 2-methyl-3-buten-2-ol (MBO), in the ambient environment. The results demonstrate the capability of the method to measure ppt levels of
water-soluble organics in air with sampling times of 10 minutes. We also provide the first measurements of 2-hydroxy-2-methylpropanal , a photooxidation product of MBO in the ambient atmospheric environment.
Impacts
The results of the first study can be used to improve limit of detection calculations, critical to determining how the data are reported in epidemiological studies. We are also contributing to understanding the developmental toxicity from human exposures to organochlorines. The results of the second study provide a method to gain insight into the role of first-, second-, and third- generation photooxidation products in tropospheric ozone and secondary aerosol formation.
Publications
- James, R. A, Hertz-Picciotto, I., Willman, E., Keller, J. A., Charles, M. J. 2002. Determinantso fo serum polychlorinated biphenyls and organochlorine pesticides measured in women from the Child Health and Development Study cohort, 1963-1967. Environmental Health Perspectives, in press.
- Willman, E., Hertz-Picciotto, I., Keller, J. A., Martinez, E., Charles, M. J. 2001. A Reproducible Approach to Reporting Organochlorine Compounds in Epidemiologic Studies, Chemosphere 44:1395-402.
- Spaulding, R. S., Talbot, R. W., Charles, M. J., 2002. Optimization of a Mist Chamber (Cofer Scrubber) for Sampling Water Soluble Organics in Air. Environ. Sci. & Tech., in press.
- Spaulding, R.S., Charles, M. J. 2002. A Comparison of Extraction and Silylation Methods for Pentafluorobenzyl Derivatives of Multi-functional Carbonyls, Analytical and Bioanalytical Chemistry, in press.
- Spaulding, R. S., Tuazon, E. C., Lashley, M., Charles, M. J. 2002. Ion Trap Mass Spectrometry Affords Advances in the Analytical and Atmospheric Chemistry of 2-hydroxy-2-methylpropanal, a Proposed Photooxidation Product of 2-methyl-3-buten-2-ol. JASMS, in press.
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