Estimation of the transport of persistent organic pollutants via air-water exchange requires precise field concentrations from advanced experimental techniques and adequate physic-chemical parameters generated from proper methods. In this study, concentrations of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and hexachlorobenzene (HCB) in the ambient air and water column of Kaohsiung Harbor lagoon were measured and used to determine the air-water exchange fluxes of these compounds from December, 2003 to January, 2005. The Whitman¡¦s thin-film model was used by taking temperature and salinity corrected Henry¡¦s law constants into the model to calculate the fluxes. In addition, particulate concentrations and composition in the ambient air and water column were used to apportion PAH sources and dry particle deposition of PAHs, PCBs and HCB. Instantaneous air-water exchange fluxes of PAHs, PCBs and HCB were calculated from twenty-two pairs of air and water samples. The highest net volatile (+3560 ng m-2 day-1) and absorptive (-1230 ng m-2 day-1) PAH fluxes in this study were both obtained from the three-ring PAH, phenanthrene on April 7 and January 27 in 2004, respectively. Differences of flux magnitude and direction between dry and rain season were obvious for PAHs in this study. Most net fluxes of PCB homologues and HCB in this study are from water to air (net volatilization). The highest net volatile flux observed was +172 ng m-2 day-1 (dichlorobiphenyl) in December, 2003 due to elevated wind speed and dissolved concentration, while the only net absorptive flux observed in this study was -0.03 ng m-2 day-1 (dichlorobiphenyl) in January, 2004. Mean daily PAH diffusive fluxes were -727 ng m-2 day-1 influx in dry season but +808 ng m-2 day -1 efflux in rain season and integrated 3.6 kg and 4.0 kg of PAHs were absorbed into and emitted from harbor lagoon surface waters in dry and rain seasons, respectively. The net PCBs and HCB fluxes suggest that the annual sum of 69 PCBs and HCB measured in this study were mainly volatile (57.4 and 28.3 ¡Ñ103 ng m-2 yr-1, respectively) and integrated 1.5 kg and 0.76 kg of PCBs and HCB emitted from harbor lagoon surface waters to ambient atmosphere in the year. Sources apportionment by the isomer ratios, PAHs in the air phase were mainly from grass, wood and coal combustion and some from liquid fuel combustion. Unlike that in air phase, fluoranthene / fluoranthene + pyrene ratios of water phase suggest PAHs were from incomplete-combusted fuel particles emitted from vehicle exhaust. Principal component analysis (PCA) extracted three meaningful PCs for air and water samples, respectively. For the air samples, the three major sources suggested by three sources are vehicular emissions, volatilization to the air from contaminated soil or waters and the coal-burning emission. Among the water samples, the three major sources suggested by three sources are vehicular emissions, oil spill source and coal-burning emission. Air particulate concentrations of PAHs, PCBs and HCB were also used to calculate their dry particle deposition. Throughout our sampling campaigns, PAH dry particle fluxes were quite comparable to fluxes of air-water exchange. On the contrary, PCB and HCB dry particle deposition flux were negligible comparing to their air-water exchange fluxes. Our results suggest PAHs exhibits strong absorptive or weaker volatile fluxes in the dry season but the opposite in the rain season. However, for PCBs and HCB, Kaohsiung Harbor water is potentially an important source to ambient air.

The Great Lakes has been impaired by elevated concentrations of contaminants, and different regulatory actions are taken to decrease theses concentrations. Recent research of Dr. Azim suggests a decline in mercury levels in the Lake Erie, and an increase in the Hg concentration in the fish communities. This research is a follow up study to examine whether the contaminant levels are indeed increasing. In the first chapter we evaluate the temporal trends of polychlorinated biphenyls (PCBs) in Lake Erie fish over the last 30 years by conducting the Exponential and Dynamic Linear Modeling analysis. DLM analysis in the chapter two detects the PCB and Hg contaminant trends in a broader range. There is a high variability in two contaminants trends. These patterns may be because of factors such as fish physiological parameters, and the impact of invasive species. The results of my research will contribute to the Toxics Reduction Strategy.

The Great Lakes has been impaired by elevated concentrations of contaminants, and different regulatory actions are taken to decrease theses concentrations. Recent research of Dr. Azim suggests a decline in mercury levels in the Lake Erie, and an increase in the Hg concentration in the fish communities. This research is a follow up study to examine whether the contaminant levels are indeed increasing. In the first chapter we evaluate the temporal trends of polychlorinated biphenyls (PCBs) in Lake Erie fish over the last 30 years by conducting the Exponential and Dynamic Linear Modeling analysis. DLM analysis in the chapter two detects the PCB and Hg contaminant trends in a broader range. There is a high variability in two contaminants trends. These patterns may be because of factors such as fish physiological parameters, and the impact of invasive species. The results of my research will contribute to the Toxics Reduction Strategy.

Se llevaron a cabo cuatro experimentos con el objetivo de evaluar el efecto de la utilización de grasas alteradas o contaminadas recicladas de la alimentación humana, sobre el rendimiento productivo y la salud de pollos de carne, Para ello se utilizaron indicadores tales como incidencias y productividad; niveles de oxidación en sangre (tasa de hemólisis y sustancias reactivas al ácido tiobarbitúrico, TBARs); variación de la microbiota intestinal por t-RFLP; actividad microbiana fermentativa (AGVs) y presencia de microorganismos patógenos (coccidias), además de variaciones en la histomorfología intestinal (longitud de vellosidades, profundidad de criptas y conteo de linfocitos intraepiteliales).Los tratamientos dietéticos fueron elaborados por la Universidad Politécnica de Valencia sobre una ración base constituida de maíz y soja, suplementada con un 6 % de la grasa reciclada y se diferenciaban según el nivel de alteración alto (H) y bajo (L). Los cuatro experimentos contenían los siguientes niveles de alteración o contaminación: Experimento T, Ácidos grasos trans (HT=12,40 % y LT=0,65 %); Experimento D, dioxinas y PCBs (HC=28,80 pg y LC=9,64 pg TEQ/g PCDD/Fs+DL-PCBs de aceite); Experimento P, hidrocarburos aromáticos policíclicos (HP=5,291 ng HAPs/g y LP<18 ngHAPs/g de aceite) y Experimento O, productos de oxidación (HO=6,61 % Polímeros y 67,43 p-anisidina y LO=0,35 % Polímeros y 2,74 p-anisidina).La productividad y salud de los animales, no fue afectada por los tratamientos experimentales, excepto en el caso de la prueba experimental (T), en la que los animales alimentados con la dieta que contenía el nivel de alteración bajo (LT), presentaron un mejor índice de transformación alimenticia (P=0,003), que los animales alimentados con la dieta HT.Un mayor grado de saturación (experimento T) de la grasa del tratamiento HT, se tradujo en una mayor fragilidad (tasa de hemólisis) de la membrana de los eritrocitos (P=0,002), en comparación a su homólogo LT. El efecto de la edad, se tradujo en diferencias estadísticamente significativas (P<0,001), entre animales jóvenes (9 días) y animales de mayor edad (37 días de vida).La evaluación de los dendogramas obtenidos en los cuatro experimentos (t-RFLP) demostró que la composición de la flora microbiana no fue influenciada por los tratamientos. La concentración total de AGVs (actividad microbiana) en las muestras de contenido cecal de los cuatro experimentos no fue afectada por los tratamientos. En cuanto a la presencia de microorganismos patógenos (coccidias) se observó un claro efecto de los tratamientos (P=0,001). No obstante, el conteo ooquistes por gramo, no superó los niveles de concentración considerados peligrosos desde el punto de vista epidemiológico y no se acompañaron de manifestaciones clínicas. El nivel de alteración o contaminación estudiado, no tienen un efecto directo sobre la histomorfología gastrointestinal. Por el contrario, la edad tuvo un efecto significativo, traducido en un general aumento (P<0,001) de la longitud de la vellosidades (LV), una disminución (P<0,001) en las profundidad de criptas (PC) y un descenso (P<0,001) en la proporción de linfocitos intraepiteliales (IEL). Con relación al cociente V/C (relación vellosidad/cripta), en todos los experimentos se alcanzaron los mayores cocientes a 21 días de vida (P<0,001), que a los 9 días de vida de las aves. En conclusión, el nivel de alteración o contaminación estudiado, no presenta un claro efecto sobre los indicadores de salud o productividad analizados. Por el contrario, con la edad del ave aumenta la resistencia a la hemólisis de los eritrocitos, la complejidad de la microbiota cecal y en paralelo, incrementa la longitud de las vellosidades acompañado de un descenso proporcional de la profundidad de criptas y del número de linfocitos intraepiteliales. / Four experiments were realised with the aim of evaluating the effect of the recycled fats of the human feeding on the productive yield and the health of the chickens. Indicators were used such as incidences and productivity; levels of oxidation in blood (rate of haemolysis and reactive substances to tiobarbitúrico acid, TBARs); variation of the intestinal microbiota by t-RFLP; microbial activity (AGVs) and presence of pathogenic microorganisms (coccidias), besides variations in the intestinal histomorfología (length of villious, depth of cripts and count of intraepithelial lymphocytes). The dietetic treatments were elaborated by the Polytechnical University of Valencia on a ration bases constituted of maize and soybean, supplemented with a 6% of the recycled fat and was different itself according to the high level of alteration (H) and low (L). The four experiments contained the following levels of alteration or contamination: Experiment T, Fatty acids trans (HT= 12.40% and LT= 0.65%); Experiment D, dioxins and PCBs (HC=28,80 pg and LC=9,64 pg TEQ/g PCDD/Fs+DL-PCBs of oil); Policiclic aromatic hydrocarbons (HP=5,291 ng HAPs/g and LP<18 ngHAPs/g of oil) y Experiment O, oxidation products (HO=6,61 % Polymer y 67,43 p-anisidine and LO=0,35 % Polymer and y 2,74 p-anisidine). The productivity and health of the animal, were not affected by the experimental treatments, except in the case of the T experiment, in which the animal fed with the diet that contained the level of alteration under (LT), presented a better transformation rate (P=0,003), that the animal fed with the HT. the diet with greater degree of saturation (experiment T) of the fat of treatment HT, it was translated in a greater fragility (haemolysis rate) of the erythrocytes membrane (P=0,002), in comparison to its homologous LT. The effect of the age, was translated in statistically significant differences (P<0,001) between young animal (9 days) and animal of greater age (37 days of age). The evaluation of dendrograms obtained in the four experiments (t- RFLP) demonstrated that the composition of the microbial flora was not influenced by the treatments. The total concentration of VFAs (microbial activity) in the samples of caecal content of the four experiments was not affected by the treatments. As far as the presence of pathogenic microorganisms (coccidia) a clear effect of the treatments was observed (P=0,001). However, the count oocysts, did not surpass the dangerous levels of concentration considered from the point of view epidemiologist and they were not accompanied by clinical manifestations. The level of alteration or studied contamination does not have a direct influence on the gastrointestinal morphology. On the contrary, the age had a significant effect, translated in a general increase (P<0,001) of the villious length (LV), diminishes (P<0,001) of the cript depth (PC) and the diminishes of the intraepithelial lymphocytes (IEL).In conclusion, the level of alteration or studied contamination, does not present a clear effect on the indicators of analyzed health or productivity. On the contrary, with the age of the bird it increases the resistance to the haemolysis of erythrocytes, the complexity of the cecal microbiota and in parallel it increases the length of the intestinal villious accompanied by a proportional reduction of the depth of cripts and the number of intraepithelial lymphocytes.

Environmental field analysis provides advantages that allow real-time decisions, interactive sampling and cost effective solutions to the problems faced at the time of investigation. Gas chromatography (GC), a widespread technique for the determination of organic pollutants in the environment, has also shown to be useful in environmental field analysis. Thermal desorption of solid environmental sample provides a technique for liberation of volatile analytes from the samples without the need for solvent extraction. Combining the thermal desorption technique with a field gas chromatograph (GC) thus provides the possibility of on-site determination of organic contaminants in soils. However, to better characterize trace level contaminants in complex sample matrices, laboratory analysis using analytical instrument with great separation and resolution power is required. Comprehensive two-dimensional gas chromatography (GC X GC) is such a powerful analytical tool that provides enhanced separation and resolution capacity for the task. The project presented here involves the development and validation of a field method for the analysis of total polychlorinated biphenyls (PCBs) in soils, and determination of individual PCB congeners in the same samples by further laboratory analysis. The field analytical system developed was a field portable GC interfaced with a thermal desorber. The identification of PCB congeners was realized by a GC X GC system with a time-of-flight mass spectrometer (TOF-MS) as a detector. The field method was developed by optimizing and characterizing the method using PCB standards, followed by the application of the developed method to environmental soil samples. Finally, analyses of PCB congeners in environmental soil samples were performed using the GC X GC system.

Environmental field analysis provides advantages that allow real-time decisions, interactive sampling and cost effective solutions to the problems faced at the time of investigation. Gas chromatography (GC), a widespread technique for the determination of organic pollutants in the environment, has also shown to be useful in environmental field analysis. Thermal desorption of solid environmental sample provides a technique for liberation of volatile analytes from the samples without the need for solvent extraction. Combining the thermal desorption technique with a field gas chromatograph (GC) thus provides the possibility of on-site determination of organic contaminants in soils. However, to better characterize trace level contaminants in complex sample matrices, laboratory analysis using analytical instrument with great separation and resolution power is required. Comprehensive two-dimensional gas chromatography (GC X GC) is such a powerful analytical tool that provides enhanced separation and resolution capacity for the task. The project presented here involves the development and validation of a field method for the analysis of total polychlorinated biphenyls (PCBs) in soils, and determination of individual PCB congeners in the same samples by further laboratory analysis. The field analytical system developed was a field portable GC interfaced with a thermal desorber. The identification of PCB congeners was realized by a GC X GC system with a time-of-flight mass spectrometer (TOF-MS) as a detector. The field method was developed by optimizing and characterizing the method using PCB standards, followed by the application of the developed method to environmental soil samples. Finally, analyses of PCB congeners in environmental soil samples were performed using the GC X GC system.

Persistent organic pollutants (POPs) were widely distributed in the environment, and may cause hazardous effects to human health. Among these pollutants, polychlorinated biphenyls (PCBs), due to their toxicity and bioaccumulation, have been banned in the mid 1970s in most countries. They are ubiquitous and highly persistent, and therefore, PCBs are of most concern for their potential to be globally transported through air-water exchange. Previous studies such as Fang et al.¡]2008¡^ and Chen¡]2010¡^have studied the air-water exchange of PCBs in Kaohsuing Harbor. This study not only continued monitoring this area but also included Gao-Ping coastal areas and Lanyu Island in order to determine the air-water exchange fluxes of PCBs in harbor and coastal area. The aim of this study was to determine the magnitude of PCB air-water exchange fluxes and dry deposition fluxes by measuring the gas/particle phase concentrations in ambient air and dissolved/particle phase concentrations in water column, and to analyze the compositional patterns of PCB homologs. Hierarchical cluster analysis (HCA) and principal components analysis (PCA) were performed with compositional patterns of commercial products such as Aroclor mixtures to gain a better understanding of pollution topography for PCBs . The concentrations of £UPCBs in the ambient air ranged from 116 to 439 pg m-3, with an average concentration of 164 pg m-3 . The average PCB concentrations in gas and particle phase were 161 pg m-3 and 2.91 pg m-3, respectively. The concentrations of £UPCBs in water column ranged from 14.1 to 1750 pg L-1, with an average concentration of 233 pg L-1. The average PCB concentrations in dissolved and particle phase were 162 pg L-1 and 70.4 pg L-1, respectively. The highest gaseous concentration of £UPCBs was observed in GRE in November, suggesting that wind direction and Linyuan Industrial Park may be the major contributor of PCBs there. However, the highest dissolved concentration of £UPCBs was found in KHH in August, indicating that rainfall and runoff of Typhoon Morakot were evident in source. Results from HCA, PCA and compositional patterns indicate that lower chlorinated congeners (dichlorobiphenyls to tetrachlorobiphenyls) were predominant in the gas and dissolved phase of ambient air and water column. In particle phase of ambient air and water column, PCB compositions were dominated by higher chlorinated congeners (tetrachlorobiphenyls to hexachlorobiphenyls). TEQ was used to determine the level of pollution for environment and human health. The average TEQ was 0.0008 pg-TEQ m-3 in gas-phase of ambient air and was 0.0006 pg-TEQ L-1 in dissolved phase in water. PCB114 was observed to be the predominant congener in this study. The average flux of air-water exchange was ¡Ï31.5 ng m-2 day-1, and was much higher than the average flux of dry deposition (¡Ð0.54 ng m-2 day-1). The net PCB fluxes in KHH suggest that annual air-water exchange was ¡Ï40.2 mg m-2 yr-1 and estimated yearly, 0.5 kg of PCBs were emitted from water column of Kaohsiung harbor to the ambient atmosphere.

Endocrine-disrupting chemicals (EDCs) are environmental pollutants known to perturb hormone systems and interfere with normal endocrine function. Exposure to EDCs during hormone-sensitive developmental periods can result in profound dysfunction in reproductive physiology and behavior. In this dissertation, effects of gestational exposure to a class of EDCs called polychlorinated biphenyls (PCBs) were examined in the developing hypothalamus, which is known to control reproductive physiology and behavior in vertebrates. The specific hypothesis was that PCBs caused changes in sexually dimorphic hypothalamic nuclei, resulting in perturbation of adult sociosexual behaviors and alteration of neural networks with changes in expression of microRNAs and genes during development and in adulthood. This research focused on two brain areas relevant to understanding the PCB effects on the developing hypothalamus: 1) microRNA and related target gene expression during postnatal development, 2) adult sociosexual behaviors and gene expression. In both sections, molecular changes were examined in two sexually dimorphic hypothalamic nuclei, medial preoptic nucleus (MPN) and ventromedial nucleus (VMN), known for their role in regulation of sociosexual behavior. In the first section of the dissertation, the effects of PCBs were examined on the expression of microRNAs and target genes at four ages during postnatal [P] development (P15, P30, P45, and P90). Age and sex specific effects were observed in both MPN and VMN, with greater effects in the MPN. The second research section of the dissertation explored whether sociosexual behaviors, namely ultrasonic vocalizations and sociosexual preference behaviors, were altered by gestational PCBs. Expression of forty-eight neuroendocrine candidate genes was also examined in the MPN and VMN of the same animals. Several sociosexual behaviors were affected, including number and acoustic properties of ultrasonic vocalizations, and nose-touching with opposite-sex animals. Gene expression was altered in sex and region-specific manner in the brains of behaviorally affected rats. Taken together, these findings suggest that gestational PCBs have lasting effects on molecular mechanisms during postnatal development and in adulthood, and could result in altered sociosexual behavior. These results have implications for human health and disease, as early life exposures to EDCs have been linked to reproductive decline in humans. / text

Accurate characterization of risk of adverse ecological effects related to contaminated sediment presents a particularly difficult challenge. A series of studies has been conducted to investigate the utility of various tools for assessment of sediment toxicity. The goal of this research was to provide information which could help increase the accuracy with which predictions of toxicity could be made at hazardous sites. A calibration study was conducted using model PAHs, PCBs, a binary PAH mixture and a coal-tar mixture. This study was a collaborative effort among five university-based Superfund Research Programs (SRPs). Each program, with the help of funding through the NIEHS Superfund Research Program, has developed a chemical-class specific assay to estimate toxicity of contaminants in sediment. This suite of bioassays expands the range of data typically obtained through the use of standard aquatic toxicity assays. A series of caged in situ exposure studies has been conducted using juvenile Chinook salmon and Pacific staghorn sculpin in the Lower Duwamish Waterway. The study aimed to investigate the utility of selected biomarkers in evaluating the relationship between contaminants present in environmental samples and response in receptors following an in situ caged exposure. Results found that DNA adducts detected in exposed fish were significantly higher than controls in 2004 and 2006, and DNA adducts appear to be a reliable indicator of exposure, although no dose-response relationship was present. Western blot analysis of CYP1A1 was not indicative of exposure levels. The final study conducted was concerned with evaluating the utility of using solid phase microextraction (SPME) fibers in situ to evaluate contaminated sediment. Levels of PAHs and PCBs in sediment often exceeded sediment quality guidelines; however, results from aquatic toxicity bioassays using Hyalella azteca were mostly negative, thus levels of contaminants detected on SPME fibers could not be associated with adverse effects in Hyalella. However, regression analysis of total PAHs present in sediment and levels of PAHs detected in porewater SPME fiber samplers, which were placed 5 cm into the sediment for 30 days, revealed a strongly correlated linear relationship (R2 = .779). Normalization of the sediment data to total organic carbon was performed to determine if the trend would remain present, and the linear relationship was again confirmed (R2 =.709).

In recent years, lower-chlorinated, airborne congeners of polychlorinated biphenyls (PCBs) have evolved as an emerging class of potentially hazardous environmental contaminants. Previous work has demonstrated that sulfation is a major metabolic pathway for these PCBs in vitro and in vivo; however, their metabolic fate and toxicities have not been explored. Hypothyroxinemia is among the most prevalent adverse health effects associated with PCB exposure in human populations and is an assumed cause of a variety of neurodevelopmental effects observed in infants following prenatal PCB exposure. The displacement of L-thyroxine (T4) from binding sites on transthyretin (TTR), a major T4 transport protein and trans-placental carrier of thyroid hormones, is thought to be a significant contributing factor in PCB-induced hypothyroxinemia. Structural similarities between sulfated metabolites of PCBs and T4 led to the central hypothesis that PCB sulfates are bioactive metabolites that exhibit high affinity binding to T4 binding sites on human TTR. An examination of the ability of six lower-chlorinated PCB sulfates to bind to human TTR in vitro, as well as subsequent computational modeling, revealed that these compounds interact with the high-affinity binding site in a non-covalent manner and with affinities comparable to T4. Corroborating evidence for the binding of PCB sulfates stems from their ability to inhibit the formation of TTR amyloid fibrils through stabilization of the protein's native conformation. Fibrillar TTR aggregates are the cause of amyloidoses like senile systemic amyloidosis, familial amyloid polyneuropathy and familial amyloid cardiomyopathy. All PCB sulfates examined were effective inhibitors of TTR fibrillogenesis with equal or higher efficiencies than some of the best previously described inhibitors. In vivo exposure of male Sprague-Dawley rats to a model PCB sulfate, 4-PCB 11 sulfate, resulted in rapid and widespread distribution of the metabolite to various organs, including the brain. Consequently, there is a strong indication for a potential role of PCB sulfates in thyroid disruption and inter-tissue transport of PCBs, and the binding of PCB sulfates to TTR may also provide structural information for improved design of anti-amyloid therapeutics. To date there are no analytical procedures for the quantification of PCB sulfates available, and exposure levels in human populations remain unknown. This study provides, for the first time, evidence that PCB sulfates, if present in human serum samples, are not extracted by current standard protocols for the analysis of PCBs and their metabolites. Consequently, PCB sulfates may have been overlooked in the past decades resulting in potential underestimation of total PCB exposure levels in exposed populations. Based on this finding, an efficient approach for the quantitative extraction of PCB sulfates from a variety of biological samples was developed. This procedure, coupled with quantitative mass spectrometry, has been validated for the future screening of human serum samples, and it was successfully applied to determine the tissue distribution and elimination profile of 4-PCB 11 sulfate in male Sprague-Dawley rats.