Browsing by Author "Kinniburgh, David W."
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- ItemOpen AccessEuropean Starlings as Sentinels for Health Effects of Urban Air Pollution(2017) North, Michelle Alison; Smits, Judit E. G.; Kaplan, Gilaad; Kinniburgh, David W.; Bertazzon, StefaniaThe consequences of exposure to air pollution are widely studied in humans, with urban pollutants associated with a suite of adverse health outcomes. With the complexity of air pollutant mixtures thwarting our full understanding of effects in humans, the consequences to urban wildlife are even less well-understood. The intricate, highly efficient respiratory system of birds makes them more sensitive to airborne toxicants than other vertebrates. The motivation for this study is to identify sensitive, reliable biomarkers of biological effects of air pollutants using wild European starlings (Sturnus vulgaris). This was achieved using two approaches: a field study investigation disclosed the effects of ambient exposure on nestling starlings, whereas experimental exposure of adult starlings to vehicle emissions provided insights under controlled conditions. In both studies, pollutant exposures were measured using several techniques to provide as accurate information as possible. Passive air samplers measured the concentrations of nitrogen dioxide, sulphur dioxide, and volatile organic compounds in ten urban parks in Calgary, Canada during May and June of 2013 to 2015, and during the experiment in May 2016. For the field study, the reproductive success of adult starlings, growth and development of their offspring, biomarkers of oxidative stress, hepatic detoxification effort, and T-cell mediated immune response were evaluated as biomarkers of contaminant effects. The relative contributions of confounding predictors were assessed, while clustering within nest and location were included during analyses. For the experimental study, the same biomarkers were measured in adult, wild-caught, non-breeding starlings, with additional measurements of B-cell immunity, thyroid hormones and histology. Several responses in nestlings indicated that higher exposures to benzene, toluene, ethylbenzene, xylenes (BTEX) and hexane had physiological costs, which, although subtle, may reduce the resilience of nestlings to cope with additional stressors such as fledging. Similarly, subclinical endocrine and immune changes in experimental birds suggest that higher exposures, or the exposure at sensitive life stages, may have population-level consequences.
- ItemEmbargoFormation Potential and Analysis of 32 Regulated and Unregulated Disinfection By-Products: Two New Simplified Methods(Elsevier, 2022-04-23) Murakami, Jillian N.; Zhang, Xu; Ye, Joanne; MacDonald, Amy M.; Pérez Pérez, Jorge; Kinniburgh, David W.; Kimura, Susana Y.Water disinfection is an essential process that provides safe water by inactivating pathogens that cause waterborne diseases. However, disinfectants react with organic matter naturally present in water, leading to the formation of disinfection by-products (DBPs). Multi-analyte methods based on mass spectrometry (MS) are preferred to quantify multiple DBP classes at once however, most require extensive sample pre-treatment and significant resources. In this study, two analytical methods were developed for the quantification of 32 regulated and unregulated DBPs. A purge and trap (P&T) coupled with gas chromatography mass spectrometry (GC-MS) method was optimized that automated sample pre-treatment and analyzed volatile and semi-volatile compounds, including trihalomethanes (THMs), iodinated trihalomethanes (I-THMs), haloacetonitriles (HANs), haloketones (HKTs) and halonitromethanes (HNMs). LOQs were between 0.02-0.4 µg/L for most DBPs except for 8 analytes that were in the low µg/L range. A second method with liquid chromatography (LC) tandem mass spectrometry (MS/MS) was developed for the quantification of 10 haloacetic acids (HAAs) with a simple clean-up and direct injection. The LC-MS/MS direct injection method has the lowest detection limits reported (0.2-0.5 µg/L). Both methods have a simple sample pre-treatment, which make it possible for routine analysis. Hyperchlorination and uniform formation conditions (UFC) formation potential tests with chlorine were evaluated with water samples containing high and low TOC. Hyperchlorination formation potential test maximized THMs and HAAs while UFC maximized HANs. Ascorbic acid was found to be an appropriate quencher for both analytical methods. Disinfected drinking water from four water utilities in Alberta, Canada were also evaluated.
- ItemOpen AccessPhytoestrogens in Human Pregnancy(2012-05-14) Jarrell, John; Foster, Warren G.; Kinniburgh, David W.Background. The hormonal milieu associated with pregnancy has become a focus of interest owing to potential links with the developmental origins of health and disease. Phytoestrogens are hormonally active plant-derived chemicals that may have an impact on human reproductive processes. However, developmental exposure to phytoestrogens has not been well characterized and thus our objective was to quantify phytoestrogen exposure during pregnancy and lactation. Methods. Women in the second trimester of pregnancy entered the study during counseling for prenatal genetic information. Women who had an indication for a genetic amniocentesis on the basis of late maternal age were approached for inclusion. They completed an environmental questionnaire; a sample of amniotic fluid was collected for karyotype, blood was collected from women during pregnancy and at birth, from the umbilical cord and breast milk. Samples were tested for the presence of daidzein and genistein by GC Mass Spectroscopy. Findings. Phytoestrogens are commonly found in pregnant women’s serum and amniotic fluid during pregnancy. There is a sex difference in the concentrations with higher levels in amniotic fluid containing female fetuses. This difference was not present in maternal serum. Soy ingestion increases amniotic fluid phytoestrogen concentrations in female and male fetuses. The presence and concentrations of phytoestrogens did not differ in relation to common pregnancy complications or preexisting infertility.
- ItemOpen AccessToxic cyanobacteria in relation to sulfate, molybdenum, nitrogen and phosphorus in Alberta's shallow prairie lakes(2018-10-19) Anderson, Susan Marie; Jackson, Leland J.; Kinniburgh, David W.; Vamosi, Steven M.; Vamosi, Jana C.Cyanobacteria are characteristic of poor global water quality. They create a public health concern and threaten biodiversity, particularly when they produce toxins such as microcystins. It is poorly understood why cyanobacteria produce microcystins, or how cyanobacteria in shallow prairie lakes will respond to increased salinity under changing climate. To study the effects of variable sulfate concentrations on cyanobacteria and to elucidate environmental patterns of microcystin production, I sampled 25 shallow lakes over four months for total nitrogen (TN), dissolved inorganic nitrogen (DIN), total phosphorus (TP), soluble reactive phosphorus (SRP), sulfate, molybdenum, microcystins, and the cyanobacteria-specific pigments canthaxanthin, myxoxanthophyll and echinenone. There was a negative relationship between cyanobacteria pigment and sulfate, and a positive relationship between cyanobacteria pigment and molybdenum and total nitrogen. Microcystins positively correlated with cyanobacteria pigment and turbidity. When microcystin samples above 10 µg·L-1 were removed, microcystins correlated with TN:TP in June and July. My results suggest that increasing sulfate leads to less cyanobacteria pigment. With the prairies expected to get hotter and dryer in the future, shallow prairie lakes are likely to see less cyanobacteria as they increase in salinity. My results also indicate that higher cyanobacteria pigments correlate with higher microcystins. Although low TN:TP can lead to high microcystins, low TN:TP is not enough to differentiate between high and low microcystins. No thresholds were found in either analysis, meaning there was no evidence for a tipping point where sulfate limits cyanobacteria nor the existence of environmental triggers associated with microcystin production over the season.