Alkylated polycyclic aromatic hydrocarbons (alkyl-PAHs) are major constituents of crude oil, and the 3-5 ringed alkyl-PAHs have been identified as the main components chronically toxic to fish. While chysene homologues have higher cytochrome P4501A (CYP1A) induction potencies than alkyl-phenanthrenes, there is little characterization of toxicity for 4-ringed alkyl PAHs. This study measured the chronic toxicity of chrysene, benz[α]anthracene, and some alkylated congeners to the embryos of Japanese medaka (Oryzias latipes) using the partition-controlled delivery method (PCD) of exposure. This exposure method relies on the partitioning of chemicals from polydimethylsiloxane (PDMS) films, loaded with various concentrations of test chemical, to embryo rearing solutions. The objectives of this thesis were: (1) to further characterize the PCD method with a series of 4-ringed PAHs; (2) to evaluate the effects of different chemical structures on the toxicity of test compounds; and (3) to extend structure toxicity relationships from alkyl-phenanthrenes. The PCD method generated a gradient of aqueous concentrations for test compounds, and these exposure concentrations were maintained constant for the 17-day period. Benz[α]anthracene showed higher toxicity than chrysene. Toxicity increased with the degree of alkylation on the ring structures, except that 2-methylbenz[α]anthracene was less toxic than the unsubstituted benz[α]anthracene. Substitutions at the middle region contributed to a higher toxicity than substitutions at the distal region. While actual mechanisms for these compounds to cause toxicity are unknown, the narcotic mode of action seems to be not involved due to the lack of mortality. Within the range of test concentrations, the chronic sublethal toxicity was limited by the low solubility of the test compounds. A structure toxicity relationship was illustrated by the regression between log EC50s and log Kow values. In addition to hydrophobicity represented by log Kow, structural dissimilarities between compounds and physical characteristics such as aqueous solubility limits should be taken into account in toxicity assessments with alkyl-PAHs. This research is the first toxicological assessment of alkyl-chrysenes and benz[α]anthracenes which is essential for a better understanding of structure toxicity relationships of alkyl-PAHs, and will contribute to more accurate ecological risk assessments of PAH contamination. / Thesis (Master, Biology) -- Queen's University, 2014-01-10 16:35:00.232

Human activities over the years, especially the unconventional exploitation of oil sands deposits, downstream on the Athabasca River (AR), might have affected the water quality and ecological integrity of the river basin, thereby presenting a threat to the environment and human health. There have been concerns that the oil sands process-affected waters stored in tailing ponds may be percolating to surface waters as well as underground waters, contaminating neighboring watersheds with a cocktail of chemicals including Polycyclic aromatic hydrocarbons (PAHs). PAHs are present both naturally and from human activities as pollutants in the environment. Forest fires, geologic activities, and oil seeps are examples of natural sources of PAHs in the environment. The major sources of PAHs in the Athabasca region are leaching of oil sands deposits and contamination from oil sands production. On occasions, forest fires contribute PAHs in the area. There has been no comparative data on the exposure of PAHs to fish along the AR and Slave River. I used an integrative monitoring of selected fishes as an indicator to achieve four objectives: i) describe the spatial and seasonal distribution of measurable concentrations of products of biotransformation of polycyclic aromatic hydrocarbons (PBPAH) in bile of fish; ii) determine the levels of parent PAHs in the muscle of fish, and extrapolate the data to estimate potential risk to human consumers, and to identify which species and geographic regions, if any, pose the greatest risk to humans; iii) use patterns of contamination to provide a scientific basis for elucidating the source of contamination; and iv) perform fish health investigation by collecting morphometric health measures and perform a systematic assessment of the occurrence of lesions in the fishes. I sampled whitefish (Coregonus clupeaformis), jackfish/northern pike (Esox luscius), walleye (Sander vitreus), goldeye (Hiodon alosoides) and burbot (Lota lota) from Fort McMurray, Fort McKay, and Fort Chipewyan in Alberta, and from Fort Smith and Fort Resolution on the Slave River in the Northwest Territories. The rationale for selecting fishes included: their abundance along the basin (some have short ranges, e.g., northern pike); their dietary/nutritional and cultural significance to communities in the area; their feeding strategy, such as benthic, supra-benthic, or pelagic, trophic status, and patterns of migration and habits of spawning. I addressed the first objective in Chapter 2, where the total PBPAHs were determined. Concentrations of products of biotransformation of 2 and 3-ringed, 4-ringed, and 5-ringed PAHs were measured using synchronous fluorescence spectroscopy. Spatial and seasonal differences were observed with greater concentrations of PBPAHs in samples of bile of fish collected from Fort McKay as well as greater concentrations of PBPAHs in bile of fish collected during summer compared to those collected in other seasons. Overall, PBPAHs were greater in fishes of lower trophic levels and fishes more closely associated with sediments. In particular, goldeye (Hiodon alosoides), consistently contained greater concentrations of all the PBPAHs studied. In Chapter 3, I achieved the second objective by measuring levels of parent PAHs in muscle of selected fishes and extrapolated the results to determine potential human health risks due to fish consumption. Dorsal muscle of fishes from upstream reaches of the AR close to oil sands extraction and upgrading activities, contained greater concentrations of individual PAHs than concentrations in muscle of fishes from further downstream in the Slave River. Risks posed by PAHs to humans were assessed using a B[a]P equivalents approach. According to the risk assessment results, the average lifetime risk of additional cancers for humans who consumed fish was less than 10-6. In Chapter 4, alkylated PAHs were also measured in fish muscle to achieve the third objective. The general presence of naphthalenes and phenanthrenes and the evaluation of molecular ratios (i.e., LMW/HMW alkyl-PAHs) allowed me to conclude that the major source of pollution is petrogenic, probably due to increases in oil sand activities around Fort McMurray and Fort McKay. I achieved the fourth objective in Chapter 5 by studying the health status and potential effects of industrial development on individuals of economically and culturally significant fishes. A resurgence in condition factor of all species after a low in 2011 was observed. Annual variation was also observed in condition factor and the incidence of anomalies or lesions. Morphometric data demonstrated relatively consistent health among fishes in both the Athabasca and Slave rivers. Analysis of condition factor and somatic indices did not demonstrate consistent differences along the river system. Overall, the health of fish as determined by the metrics employed in this study, does not appear to be adversely affected by the current level of development in the Alberta oil sands region. The data presented in this dissertation make invaluable contribution to the much needed monitoring program in the Athabasca and Slave Rivers. Overall, my findings provide baseline data on fish health, concentrations of parent and alkylated PAHs, and products of biotransformation of PAH in five species of large-bodied fishes consumed by humans in communities in the Lower Athabasca and Slave River basin. These results will be useful for establishing the status and trends and spatial distribution of PAHs during monitoring of the lower Athabasca basin and most importantly, as a valuable reference point before any potential permitted discharges of wastewaters from processing of oil sands to the AR.

<p>Air pollutants pose a high risk for humans, and the environment, and this pollution is one of the major environmental problems facing modern society. Active air sampling is the technique that has been traditionally used to monitor nonpolar aromatic air pollutants. However, active high volume samplers (HiVols) require a power supply, maintenance and specialist operators, and the equipment is often expensive. Thus, there is a need to develop new, less complicated sampling techniques that can increase the monitoring frequency, the geographical distribution of the measurements, and the number of sites used in air monitoring programs. In the work underlying this thesis, the use of semipermeable membrane devices (SPMDs) as tools for monitoring gas phase concentrations of nonpolar aromatic compound was evaluated using the compound classes polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), alkylated PAHs (alkyl-PAHs) and nitrated PAHs (nitro-PAHs) as test compounds. </p><p>High wind-speeds increased the uptake and release in SPMDs of PAHs and PCBs with log K_OA values > 7.9, demonstrating that the uptake of most nonpolar aromatic compounds is controlled by the boundary layer at the membrane-air interface. The use of a metal umbrella to shelter the SPMDs decreased the uptake of PAHs and PCBs by 38 and 55 percent, respectively, at high wind/turbulence, and thus reduced the wind effect. Further, the use of performance reference compounds (PRCs) to assess the site effect of wind on the uptake in SPMDs reduced the between-site differences to less than 50 percent from as much as three times differences in uptake of PCBs and PAHs. However, analytical interferences reduced the precision of some PRCs, showing the importance of using robust analytical quality control.</p><p>SPMDs were shown to be efficient samplers of gas phase nonpolar aromatic compounds, and were able to determine local, continental and indoor spatial distributions of PAHs, alkyl- PAHs and nitro-PAHs. In addition, the use of the SPMDs, which do not require electricity, made sampling possible at remote/rural areas where the infrastructure was limited. SPMDs were also used to determine the source of PAH pollution, and different approaches were discussed. Finally, SPMDs were used to estimate the importance of the gas phase exposure route to the uptake of PAHs in plants. The results demonstrate that SPMDs have several advantages compared with HiVols, including integrative capacity over long times, reduced costs, and no need of special operators, maintenance or power supply for sampling. However, calibration data of SPMDs in air are limited, and spatial differences are often only semi-quantitatively determined by comparing amounts and profiles in the SPMDs, which have limited their use in air monitoring programs. In future work, it is therefore important that SPMDs are properly sheltered, PRCs are used in the sampling protocols, and that calibrated sampling rate data, or the SPMD-air partition data, of specific compounds are further developed to make determination of time weighted average (TWA) concentrations possible.</p>

Air pollutants pose a high risk for humans, and the environment, and this pollution is one of the major environmental problems facing modern society. Active air sampling is the technique that has been traditionally used to monitor nonpolar aromatic air pollutants. However, active high volume samplers (HiVols) require a power supply, maintenance and specialist operators, and the equipment is often expensive. Thus, there is a need to develop new, less complicated sampling techniques that can increase the monitoring frequency, the geographical distribution of the measurements, and the number of sites used in air monitoring programs. In the work underlying this thesis, the use of semipermeable membrane devices (SPMDs) as tools for monitoring gas phase concentrations of nonpolar aromatic compound was evaluated using the compound classes polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), alkylated PAHs (alkyl-PAHs) and nitrated PAHs (nitro-PAHs) as test compounds. High wind-speeds increased the uptake and release in SPMDs of PAHs and PCBs with log KOA values &gt; 7.9, demonstrating that the uptake of most nonpolar aromatic compounds is controlled by the boundary layer at the membrane-air interface. The use of a metal umbrella to shelter the SPMDs decreased the uptake of PAHs and PCBs by 38 and 55 percent, respectively, at high wind/turbulence, and thus reduced the wind effect. Further, the use of performance reference compounds (PRCs) to assess the site effect of wind on the uptake in SPMDs reduced the between-site differences to less than 50 percent from as much as three times differences in uptake of PCBs and PAHs. However, analytical interferences reduced the precision of some PRCs, showing the importance of using robust analytical quality control. SPMDs were shown to be efficient samplers of gas phase nonpolar aromatic compounds, and were able to determine local, continental and indoor spatial distributions of PAHs, alkyl- PAHs and nitro-PAHs. In addition, the use of the SPMDs, which do not require electricity, made sampling possible at remote/rural areas where the infrastructure was limited. SPMDs were also used to determine the source of PAH pollution, and different approaches were discussed. Finally, SPMDs were used to estimate the importance of the gas phase exposure route to the uptake of PAHs in plants. The results demonstrate that SPMDs have several advantages compared with HiVols, including integrative capacity over long times, reduced costs, and no need of special operators, maintenance or power supply for sampling. However, calibration data of SPMDs in air are limited, and spatial differences are often only semi-quantitatively determined by comparing amounts and profiles in the SPMDs, which have limited their use in air monitoring programs. In future work, it is therefore important that SPMDs are properly sheltered, PRCs are used in the sampling protocols, and that calibrated sampling rate data, or the SPMD-air partition data, of specific compounds are further developed to make determination of time weighted average (TWA) concentrations possible.