Legacy contaminant trends in the Great Lakes uncovered by the wildlife environmental quality index.

Since the 1970s, wildlife managers have prioritized the recovery of Great Lakes ecosystems from contamination by Persistent Organic Pollutants (POPs). Monitoring and quantifying the region's recovery is challenged by the diversity of legacy contaminants in the environment and the lack of benchmarks for their potential biological effects. We address this gap by introducing the Wildlife Environmental Quality Index (WEQI) based on prior water and sediment quality indices. The tool summarizes, in a single score, the exposure of wildlife to harmful levels of multiple contaminants - with harmful levels set by published guidelines for protecting piscivorous wildlife from biological impacts. We applied the new index to a combined Canadian and American dataset of Herring Gull (Larus argentatus) egg data to elucidate trends in wildlife for eight legacy industrial pollutants and insecticides in the Great Lakes. Environmental quality of the Great Lakes region (as indexed by WEQI) improved by 18% between 2002 and 2017. Improvement came from reductions in both the scope of contamination (the number of guideline-exceeding contaminants) and its amplitude (the average size of guideline exceedances) at bird colonies. But recovery was unequal among lakes, with Lake Erie showing no improvement at one extreme. Weakly- or non-recovering lakes (Erie, Ontario, Huron) were marked by inconsistent improvement in scope and amplitude, likely due to ongoing loading, sediment resuspension and other stressors reported elsewhere. Fast-recovering lakes (Superior and Michigan), meanwhile, improved in both scope and amplitude. Contrasting trends and contaminant profiles (e.g., exceedances of PCBs versus DDTs) highlight the importance of lake-specific management for equalizing recoveries. Lower environmental quality at American than Canadian colonies, particularly in Lake Huron, further suggest uneven success in - and opportunities for - the binational management of wildlife exposure to legacy contaminants.

Metals and Organohalogen Contaminants in Bald Eagles (Haliaeetus leucocephalus) from Ontario, 1991-2008.

We examined the degree of exposure of lead (Pb), mercury (Hg), and several organohalogen contaminants and its potential impact on survival of bald eagles in Ontario from 1991 to 2008. Overall, results for 43 dead or dying bald eagles collected in the province indicate that 23% (10/43) of birds died of Pb poisoning and 9% (4/43) died of suspected Hg poisoning. Pb poisoning was diagnosed based on exceedances of toxicity thresholds in liver and kidney and supported by clinical observations, necropsy results, and histology findings when available. Evidence for Hg poisoning in eagles was limited; however, Hg concentrations exceeded the toxicity threshold in kidney. Pb concentrations ranged widely in liver and kidney. Total Hg concentrations were relatively higher in kidney compared with liver and were significantly correlated with selenium (Se) concentrations in both tissues. Concentrations of p,p'-DDE and sum PCBs in livers of 12 bald eagles collected from 2001 to 2004 were likely below concentrations associated with adverse effects. Hepatic concentrations of total polybrominated diphenyl ethers were generally higher in birds collected from southern Ontario compared with northern Ontario. Potential impacts of exposure to these flame retardants and others are not known. Elevated metal exposure appears to influence survivorship and may affect the recovery of bald eagles in the province, particularly in southern Ontario and along the Great Lakes where a disproportionate number of poisoned eagles were collected. Increased efforts are needed to identify sources of exposure and develop measures to reduce metal exposure in this top predator.

Participation of immigrant women family caregivers in qualitative research.

The recruitment of articulate, expressive participants is an essential part of methodology in qualitative research. This article presents the authors' experience in the recruitment of immigrant women of Chinese and South Asian origin in an ethnographic study. The study included women caring for an adult or child family member who had a chronic health problem. Knowledge of women family caregivers' health is restricted by the failure to include diverse groups of women in research. In this article, the authors discuss issues related to recruitment and participation of immigrant women in research, including establishing access to diverse groups of women, benefits for immigrant women, and placing the researcher and research process on the same level. Practical research strategies to address these issues and engage the women in research that portrays their perspectives are presented. The authors' discussion concludes with reflection on their experience and that of other researchers.

A comparison of mercury levels in feathers and eggs of osprey (Pandion haliaetus) in the North American Great Lakes.

Osprey (Pandion haliaetus) eggs and chick feathers were collected for mercury analysis from nests at four Great Lakes study areas in Ontario (three "naturally formed" lakes in southern Ontario and one reservoir in northern Ontario) and two New Jersey study areas in 1991-1994. Adult osprey feathers were sampled from three Great Lakes study areas in 1991. Feathers sampled from chicks (approximately 28-35 days old) appear to be better indicators of local contaminant conditions since spatial patterns of mercury in known prey, yellow perch (Perca flavescens), also collected in these areas, were more similar to chick feathers than to eggs. Mercury levels were less variable in chick feathers than in eggs. Estimates of biomagnification factors using prey of known size at these areas were also less variable in feathers than in eggs. At naturally formed lakes, no significant correlation in mercury levels between eggs and chick feathers from the same nest was apparent, suggesting that the source of mercury contamination was not the same in these two tissues: mercury levels in eggs reflect mercury acquired on the breeding grounds, wintering grounds, and migratory route; mercury levels in chick feathers reflect local dietary conditions on the breeding grounds. Mercury levels in both osprey eggs and chick feathers were higher at the Ogoki Reservoir than at naturally formed lakes. Adult osprey feathers had higher mercury concentrations than chick feathers. Mercury levels in osprey eggs, chick feathers, and adult feathers did not approach levels associated with toxic reproductive effects.

Fast and sensitive laser-based enzymatic detection of the lactose operon in microorganisms.

This work investigates the ability of laser-based, time-resolved fluorometry to detect the lactose operon genetic marker in microorganisms and to study protein-DNA interactions. In the first study, rapid detection of the Escherichia coli lacZY operon inserted in two strains of Pseudomonas proposed as fungal biological control organisms was achieved. Optimization of incubation time, immobilization apparatus size, and reagent volumes, along with the laser-based instrumentation, yielded an assay capable of detecting 10(4) immobilized lac+ Pseudomonas fluorescens cells within a 30-min incubation time. In the second study, the synthesis of E. coli beta-galactosidase was monitored in "real-time" with observable enzymatic activity beginning 4 to 5 min after induction with isopropylthiogalactoside.

Real-time determination of molecular orientation in Langmuir-Blodgett monolayers on integrated-optical structures.

Waveguide linear-dichroism measurements were used in determining the molecular orientation of N-(sulfopropyl)-4-(p-dioctylaminostyryl) pyridinium in Langmuir-Blodgett monolayers upon 150-microm-thick glass (Ti:Zn) substrates in real time. Acquisition of complete spatial-decay curves in t - 1 s with P(laser) = 100 microW was made possible by combining propagation in integrated-optical structures with direct imaging of monolayer or glass fluorescence onto the active area of a charge-coupled device camera. Multichannel detection permitted measurement of optical waveguide loss coefficients and ultimately of molecular orientations in approximately 10(-3) of the amount of time required by previous methodology. The effects of sample preparation and materials processing on the accuracy and precision of dichroic ratios are discussed. Observed dichroic ratios for a hemicyanine dye revealed no measurable change in the orientation of the electronic transition-dipole moment when Langmuir-Blodgett films were deposited at different surface pressures. These results are in good agreement with the results from singly resonant second-harmonic generation experiments.

Optical preprocessing using liquid crystal televisions.

The suitability of a low-cost liquid crystal TV to function as a spatial light modulator in an optical preprocessor for an electronic pattern recognition system is investigated. The application presented is optical edge enhancement. The liquid crystal TV performs reasonably well where high-quality images are not required. Three optical edge enhancement methods are presented: spatial filtering; image cancellation; and phase cancellation. The phase cancellation method was discovered during the course of this research.