RESUMO
At-risk resident killer whale (Orcinus orca) populations of the northeastern Pacific, Canada, and their main prey, Chinook Salmon (Oncorhynchus tshawytscha), are exposed to a variety of contaminants including chemical elements from both natural and anthropogenic sources, which may be constraining their recovery. Concentrations of 36 chemical elements in subtidal surface sediments (1-435 m depth) collected from 98 sites along the British Columbia coast were used to characterize coast-wide patterns, and a subset of metals (mercury (Hg), cadmium (Cd), arsenic (As), nickel (Ni), copper (Cu), and lead (Pb)) were selected to assess Chinook Salmon and resident killer whale marine habitat quality. Principal component analysis (PCA) showed a dominance of Hg, antimony (Sb), Pb, Cu, and zinc (Zn) for Prince Rupert Harbour, Victoria Harbour, and Burrard Inlet, suggesting local sources. Based on the PCA, geochemical properties such as total organic carbon (TOC), acid volatile sulfide (AVS), and pH explained the spatial distribution of all elements in sediment (p < 0.001). Mercury, Cd, As, Ni, Cu, and Pb hotspots were identified along the coast of Vancouver Island, the central and north coast, in the Strait of Georgia, and Haida Gwaii. Bischof Island of Haida Gwaii and Ardmillan Bay on the central coast were most contaminated and enriched by Cd, determined by geoaccumulation index (Igeo) and enrichment factor (EF), respectively. Marine habitat quality was assessed by comparing metal concentrations to Canadian Sediment Quality Guidelines (SQGs). Chinook Salmon populations may be indirectly affected by metal toxicity (As > Cd and Cu > Ni > Hg > Pb) to lower trophic level prey species. Toxicity related impacts to benthic organisms as a result of exposure to elevated Cd and As concentrations in Northern Resident Killer Whale critical habitat and to Hg, Cd, As, Ni, Cu, and Pb concentrations in Southern Resident Killer Whale critical habitat may indirectly pose a threat to resident killer whale populations, highlighting a need for management actions to reduce risks associated with these metals.
Assuntos
Arsênio , Mercúrio , Metais Pesados , Poluentes Químicos da Água , Orca , Animais , Colúmbia Britânica , Cádmio/análise , Salmão , Chumbo/análise , Mercúrio/análise , Arsênio/análise , Níquel , Ecossistema , Metais Pesados/análise , Sedimentos Geológicos/análise , Monitoramento Ambiental , Poluentes Químicos da Água/análiseRESUMO
Understanding how the human brain integrates information from the environment with intrinsic brain signals to produce individual perspectives is an essential element of understanding the human mind. Brain signal complexity, measured with multiscale entropy, has been employed as a measure of information processing in the brain, and we propose that it can also be used to measure the information available from a stimulus. We can directly assess the correspondence between brain signal complexity and stimulus complexity as an indication of how well the brain reflects the content of the environment in an analysis that we term "complexity matching." Music is an ideal stimulus because it is a multidimensional signal with a rich temporal evolution and because of its emotion- and reward-inducing potential. When participants focused on acoustic features of music, we found that EEG complexity was lower and more closely resembled the musical complexity compared to an emotional task that asked them to monitor how the music made them feel. Music-derived reward scores on the Barcelona Music Reward Questionnaire correlated with less complexity matching but higher EEG complexity. Compared with perceptual-level processing, emotional and reward responses are associated with additional internal information processes above and beyond those linked to the external stimulus. In other words, the brain adds something when judging the emotional valence of music.
Assuntos
Percepção Auditiva/fisiologia , Encéfalo/fisiologia , Emoções/fisiologia , Música , Recompensa , Estimulação Acústica , Adulto , Interpretação Estatística de Dados , Eletroencefalografia , Feminino , Humanos , Masculino , Adulto JovemRESUMO
Methylmercury (MeHg) is a global environmental contaminant that bioaccumulates and has multiple toxic modes of action. Aquatic species have traditionally been the focus of wildlife toxicological research on mercury, but terrestrial organisms, including passerine birds, can be exposed to similarly elevated levels of MeHg. In this study we exposed a model passerine, the zebra finch (Taeniopygia guttata), to MeHg in ovo, as chicks only, or with a combined 'in ovo + chick' treatment. We isolated exposure to specific developmental stages through the use of egg injections (3.2 µg Hg/g egg) and controlled oral dosing of chicks (0.24 µg Hg/g bw/day from day 1 to day 30). In ovo exposure to MeHg reduced hatching success, but there was no effect of MeHg on chick growth. We found that in ovo only or chick only exposure did not have long-term effects, but there was some evidence for longer-term effects of combined 'in ovo + chick' exposure on post-fledging survival and potentially sex-biased survival which resulted in very few 'in ovo + chick' exposed females surviving to breed. These females also had lower overall breeding productivity that was mainly due to lower hatching success of their offspring, not lower chick-rearing success. We found no effect of treatment on clutch size or latency to laying among females that did lay eggs. Our study suggests that combined embryonic and nestling MeHg exposure has compounding latent effects on productivity, likely through a mechanism that influences the ability of females to lay fertile eggs that hatch.
Assuntos
Poluentes Ambientais/toxicidade , Tentilhões/fisiologia , Mercúrio/toxicidade , Animais , Desenvolvimento Embrionário , Exposição Ambiental , Feminino , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Testes de Toxicidade CrônicaRESUMO
OBJECTIVE: To examine the moderating effects of parent marital status and participation on efficacy of an online family problem-solving intervention for pediatric traumatic brain injury (TBI). METHODS: Participants were 132 adolescents (12-17 years) who had sustained a recent (<6 months) TBI and their parents. Participants were randomly assigned to the intervention (Counselor-Assisted Problem Solving, CAPS) or an Internet resource comparison (IRC) condition. CAPS was designed to support families in the initial phase following TBI, by teaching problem-solving skills and addressing common challenges. To examine the moderating effect of parent marital status, participants were divided into 4 groups (ie, CAPS married household, CAPS unmarried household, IRC married household, and IRC unmarried household). Family income and caregiver education were controlled in analyses. RESULTS: Parent marital status moderated treatment effects on adolescent externalizing behavior problems. Adolescents from married households in CAPS displayed fewer behavior problems at 6 and 18 months postbaseline compared with adolescents from unmarried households in CAPS. Among married CAPS families, there were no differences in outcomes among families where 1 or 2 parents actively participated. CONCLUSIONS: Web-based interventions for pediatric TBI, such as CAPS, are a viable option for some although not all families. Further research is needed to investigate factors that influence efficacy to match families to the most beneficial treatments.
Assuntos
Lesões Encefálicas Traumáticas/diagnóstico , Lesões Encefálicas Traumáticas/terapia , Internet , Estado Civil , Resolução de Problemas , Adolescente , Análise de Variância , Lesões Encefálicas Traumáticas/psicologia , Criança , Aconselhamento/métodos , Relações Familiares , Feminino , Seguimentos , Escala de Coma de Glasgow , Humanos , Escala de Gravidade do Ferimento , Masculino , Pais/psicologia , Projetos Piloto , Comportamento Problema , Medição de Risco , Fatores Socioeconômicos , Resultado do Tratamento , Estados UnidosRESUMO
The complex nature of ocean pollution underscores the utility in identifying and characterizing a limited number of "indicators" that enables scientists and managers to track trends over space and time. This paper introduces a special issue on indicators of marine pollution in the North Pacific Ocean and builds on a scientific session that was held at the North Pacific Marine Science Organization. The special issue highlights studies using a variety of indicators to provide insight into the identification of legacy and emerging contaminants, the ranking of priority pollutants from various sources, and the effects of contaminants on ecosystem health in the North Pacific Ocean. Examples include the use of mussels to illustrate spatial and temporal trends of a number of contaminants following the 2011 tsunami in Japan, the use of molecular marker (linear alkylbenzenes, hopanes, and polycyclic aromatic hydrocarbons) profiles to identify pollution sources, and the use of plastic resin pellets to illustrate spatial trends of petroleum pollution around the world. Stable isotopes were used to strengthen the utility of the Glaucous-winged gull (Larus glaucescens) as an indicator of marine pollution. Examples also demonstrate the development and application of biomarker approaches, including gene transcripts, oxidative stress, estradiol, hatchability, and respiration and swimming behavior abnormalities, as a function of exposure to polychlorinated biphenyls, sulfur-diesel, Pinghu crude oil, galaxolide and antifouling biocides. We provide a brief review of indicators of marine pollution, identify research gaps, and summarize key findings from the articles published within the issue. This special issue represents the first compilation of research pertaining to marine pollution indicators in the North Pacific Ocean and provides guidance to inform mitigation and monitoring efforts of contaminants in the region.
Assuntos
Monitoramento Ambiental , Poluentes Químicos da Água/análise , Poluição da Água/estatística & dados numéricos , Animais , Bivalves , Charadriiformes , Ecossistema , Japão , Oceano Pacífico , Poluição por Petróleo , Plásticos , Bifenilos PolicloradosRESUMO
Spatial and temporal variation can confound interpretations of relationships within and between species in terms of diet composition, niche size, and trophic position (TP). The cause of dietary variation within species is commonly an ontogenetic niche shift, which is a key dynamic influencing community structure. We quantified spatial and temporal variations in ringed seal (Pusa hispida) diet, niche size, and TP during ontogeny across the Arctic-a rapidly changing ecosystem. Stable carbon and nitrogen isotope analysis was performed on 558 liver and 630 muscle samples from ringed seals and on likely prey species from five locations ranging from the High to the Low Arctic. A modest ontogenetic diet shift occurred, with adult ringed seals consuming more forage fish (approximately 80 versus 60 %) and having a higher TP than subadults, which generally decreased with latitude. However, the degree of shift varied spatially, with adults in the High Arctic presenting a more restricted niche size and consuming more Arctic cod (Boreogadus saida) than subadults (87 versus 44 %) and adults at the lowest latitude (29 %). The TPs of adult and subadult ringed seals generally decreased with latitude (4.7-3.3), which was mainly driven by greater complexity in trophic structure within the zooplankton communities. Adult isotopic niche size increased over time, likely due to the recent circumpolar increases in subarctic forage fish distribution and abundance. Given the spatial and temporal variability in ringed seal foraging ecology, ringed seals exhibit dietary plasticity as a species, suggesting adaptability in terms of their diet to climate change.
Assuntos
Mudança Climática , Dieta , Ecossistema , Gelo , Focas Verdadeiras/fisiologia , Animais , Regiões Árticas , Isótopos de Carbono/análise , Peixes , Cadeia Alimentar , Isótopos de Nitrogênio/análise , Tempo , ZooplânctonRESUMO
BACKGROUND: Attrition in longitudinal research negatively affects statistical power, disrupts statistical stability, and can produce unwanted bias. OBJECTIVE: To investigate factors associated with shorter length of study participation and lower rates of study completion (ie, attrition) in a large, multisite, longitudinal, randomized, clinical trial examining the efficacy of a Web-based family problem-solving treatment following traumatic brain injury (TBI) in adolescence. SETTING: Five major trauma centers in the central and western regions of the United States. PARTICIPANTS: Children (N = 132) aged 12 to 17 years hospitalized for complicated mild to severe TBI within the previous 6 months. RESULTS: Completers had a higher primary caregiver education and higher family income than noncompleters, whereas ethnicity, latency to baseline assessment, and intervention group were not significantly associated with study completion. CONCLUSION: This is the first study that has specifically examined factors of attrition in a pediatric TBI population. The results suggest that research on pediatric TBI populations may be biased toward higher-income families and highlights the importance of designing studies with increased awareness of the impact of participant demographic factors.
Assuntos
Lesões Encefálicas/psicologia , Lesões Encefálicas/reabilitação , Instrução por Computador , Pacientes Desistentes do Tratamento , Educação de Pacientes como Assunto , Adolescente , Criança , Feminino , Humanos , Internet , Masculino , Resolução de Problemas , Fatores SocioeconômicosRESUMO
Marine mammals are typically poor indicators of point sources of environmental contaminants as a consequence of their often complex feeding ecologies and extensive movements, all of which mask the contributions of specific inputs. The release of polychlorinated biphenyls (PCBs) by a military radar station into Saglek Bay, Labrador (Canada) has contaminated marine sediments, bottom-feeding fish, seabirds, and some ringed seals, but attributing the PCBs in the latter highly mobile animals to this source is exceedingly difficult. In addition to the application of such tools as stable isotopes (δ(15)N and δ(13)C) and univariate and multivariate statistical exploration of contaminant patterns and ratios, we used satellite telemetry to track the movements of 13 seals in their transient use of different feeding areas. Reduced size of home range and core area (i.e., areas of concentrated use), as well as increased time in coastal inlets, were important determinants of increased PCB concentrations in seals reflecting the contribution of Saglek Bay. Seals were classified into the same feeding groups using both space use and their contaminant burdens 85% of the time, highlighting the link between feeding ecology and exposure to PCBs. While the PCB source at Saglek provided a strong local signal in a remote environment, this first use of satellite telemetry demonstrates the utility of evaluating space-use strategies to better understand contaminant exposure, and more specifically the contribution of contaminant hotspots to mobile predators.
Assuntos
Organismos Aquáticos/metabolismo , Monitoramento Ambiental , Bifenilos Policlorados/metabolismo , Comunicações Via Satélite , Focas Verdadeiras/metabolismo , Telemetria , Animais , Regiões Árticas , Comportamento Alimentar , Peixes , Terra Nova e Labrador , Análise de Componente Principal , Poluentes Químicos da Água/análise , Poluição da Água/análiseRESUMO
Causal evidence linking toxic injury to polychlorinated biphenyl (PCB) exposure is typically confounded by the complexity of real-world contaminant mixtures to which aquatic wildlife are exposed. A local PCB "hotspot" on the Labrador coast provided a rare opportunity to evaluate the effects of PCBs on the health of a marine mammal as this chemical dominated their persistent organic pollutant (POP) burdens. The release of approximately 260 kg of PCBs by a military radar facility over a 30 year period (1970-2000) contaminated some local marine biota, including the ringed seal (Pusa hispida). The abundance profiles of eight health-related gene transcripts were evaluated in liver samples collected from 43 ringed seals in the affected area. The mRNA transcript levels of five gene targets, including aryl hydrocarbon receptor (Ahr), interleukin-1 ß (Il1b), estrogen receptor α (Esr1), insulin like growth factor receptor 1 (Igf1), and glucocorticoid receptor α (Nr3c1) correlated with increasing levels of blubber PCBs. PCB threshold values calculated using best-fit hockey-stick regression models for these five genes averaged 1,680±206 ng/g lw, with the lowest, most conservative, being 1,370 ng/g lw for Il1b. Approximately 14% of the seals in the region exceeded this threshold. The dominance of PCBs in the seals studied enabled an assessment of the effects of this chemical on gene transcripts involved in regulating the health of a highly mobile predator, something that is rarely possible in the world of complex mixtures.
Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Bifenilos Policlorados/análise , Bifenilos Policlorados/toxicidade , Focas Verdadeiras/genética , Poluentes Químicos da Água/toxicidade , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Animais , Feminino , Fígado/efeitos dos fármacos , Fígado/fisiologia , Masculino , Terra Nova e Labrador , Focas Verdadeiras/metabolismo , Poluentes Químicos da Água/análiseRESUMO
OBJECTIVE: Adolescents sustaining traumatic brain injury (TBI) show increased prevalence of behavior problems. This study investigated the associations of parent mental health, family functioning, and parent-adolescent interaction with adolescent externalizing behavior problems in the initial months after TBI, and examined whether injury severity moderated these associations. METHODS: 117 parent-adolescent dyads completed measures of family functioning, adolescent behavior, and parent mental health an average of 108 days post-TBI. Dyads also engaged in a 10-min video-recorded problem-solving activity coded for parent behavior and tone of interaction. RESULTS: Overall, higher ratings of effective parent communication were associated with fewer externalizing behavior problems, whereas poorer caregiver psychological functioning was associated with greater adolescent externalizing behaviors. Results failed to reveal moderating effects of TBI severity on the relationship between socio-environmental factors and behavior problems. CONCLUSIONS: Interventions targeting parent communication and/or improving caregiver psychological health may ameliorate potential externalizing behavior problems after adolescent TBI.
Assuntos
Comportamento do Adolescente/psicologia , Lesões Encefálicas/psicologia , Comunicação , Pais/psicologia , Adolescente , Cuidadores/psicologia , Criança , Emoções , Feminino , Humanos , Masculino , Relações Pais-FilhoRESUMO
Research reveals mixed results regarding the utility of standardized cognitive and academic tests to predict educational outcomes in youth following a traumatic brain injury (TBI). Yet, deficits in everyday school-based outcomes are prevalent after pediatric TBI. The current study used path modeling to test the hypothesis that parent ratings of adolescents' daily behaviors associated with executive functioning (EF) would predict long-term functional educational outcomes following pediatric TBI, even when injury severity and patient demographics were included in the model. Furthermore, we contrasted the predictive strength of the EF behavioral ratings with that of a common measure of verbal memory. A total of 132 adolescents who were hospitalized for moderate to severe TBI were recruited to participate in a randomized clinical intervention trial. EF ratings and verbal memory were measured within 6 months of the injury; functional educational outcomes were measured 12 months later. EF ratings and verbal memory added to injury severity in predicting educational competence post injury but did not predict post-injury initiation of special education. The results demonstrated that measurement of EF behaviors is an important research and clinical tool for prediction of functional outcomes in pediatric TBI.
Assuntos
Sintomas Comportamentais , Lesões Encefálicas/complicações , Lesões Encefálicas/reabilitação , Transtornos Cognitivos , Educação Inclusiva/métodos , Adolescente , Sintomas Comportamentais/diagnóstico , Sintomas Comportamentais/etiologia , Sintomas Comportamentais/reabilitação , Distribuição de Qui-Quadrado , Criança , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/reabilitação , Função Executiva , Feminino , Escala de Coma de Glasgow , Humanos , Masculino , Memória , Testes Neuropsicológicos , Pediatria , Valor Preditivo dos Testes , Resultado do Tratamento , Aprendizagem VerbalRESUMO
Cerebral venous sinus thrombosis (CVST) is an uncommon but recognized complication of treatment for leukemia. Our goal was to determine the long-term neurocognitive outcomes in childhood cancer survivors who had CVST during therapy. Nine patients were identified from an institutional database. All had experienced CVST in the setting of L-asparaginase therapy in combination with other chemotherapeutic agents. Four patients completed neuropsychological evaluation. Their neurological examinations were normal. Neuropsychological testing showed that the participants performed well, with average to above-average scores on cognitive and behavioral testing. Three exhibited difficulties on a visual-motor integration task and 1 had difficulty with fine-motor dexterity, nonverbal memory, emotional control, shifting attention, and anxiety. Overall, by patient and parent report, the survivors had few problems. CVST is a known complication associated with treatment for leukemia and non-Hodgkin lymphoma, most commonly observed if asparaginase is used in combination with other chemotherapeutic agents. Although subtle difficulties were noted in survivors on neuropsychological testing, survivors themselves were not aware of the deficits. Further evaluation of leukemia survivors with a history of CVST is needed to assess for deficits and to understand whether further intervention is necessary.
Assuntos
Transtornos Cognitivos/etiologia , Linfoma não Hodgkin/psicologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/psicologia , Trombose dos Seios Intracranianos/psicologia , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Asparaginase/administração & dosagem , Asparaginase/efeitos adversos , Criança , Pré-Escolar , Cognição/efeitos dos fármacos , Transtornos Cognitivos/induzido quimicamente , Feminino , Humanos , Linfoma não Hodgkin/tratamento farmacológico , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Trombose dos Seios Intracranianos/induzido quimicamente , Adulto JovemRESUMO
OBJECTIVE: To determine the association of primary caregiver-rated behavioral and metacognitive aspects of executive function (EF) with impaired functioning after adolescent traumatic brain injury (TBI). DESIGN: Multicenter cross-sectional study. SETTING: Outpatient. PARTICIPANTS: Primary caregivers and children (N=132) aged 12 to 17 years who sustained a moderate or severe TBI within the past 1 to 6 months. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Primary caregiver ratings of EF, tests of memory and processing speed (PS), and a structured parent interview to assess clinical impairments in behavioral functioning were used. Logistic regression was used to examine the relation of ratings of EF with clinical ratings of impairment in global adolescent functioning and in functioning in the home, school, and community settings after controlling for sex, race, socioeconomic status, injury severity, and performance on the tests of memory and PS. RESULTS: Caregiver ratings of poor EF were associated with impairment in both global behavioral functioning (odds ratio [OR]=4.73; 95% confidence interval [CI], 1.54-14.52; P<.01) and community functioning (OR=13.28; 95% CI, 1.94-90.87; P<.01). CONCLUSIONS: Caregiver ratings of deficits in EF were associated with impaired behavioral functioning after adolescent TBI and were independent of performance on tests of memory and processing speed. Understanding the relation of EF with clinical impairments as manifested in different settings will help hone assessment batteries and focus treatments where they are needed most.
Assuntos
Comportamento do Adolescente , Lesões Encefálicas/fisiopatologia , Função Executiva/fisiologia , Pais , Adolescente , Estudos Transversais , Feminino , Escala de Coma de Glasgow , Humanos , Escala de Gravidade do Ferimento , Modelos Logísticos , Masculino , Testes Neuropsicológicos , Fatores SocioeconômicosRESUMO
BACKGROUND: A small body of previous research has demonstrated that pediatric traumatic brain injury (TBI) increases risk for internalizing problems, but findings have varied regarding their predictors and correlates. METHODS: We examined the level and correlates of internalizing symptoms in 130 teens who had sustained a complicated mild to severe TBI within the past 1 to 6 months. Internalizing problems were measured via both maternal- and paternal-report Child Behavior Checklist. We also measured family functioning, parent psychiatric symptoms, and postinjury teen neurocognitive function. RESULTS: Mean parental ratings of internalizing problems were within the normal range. Depending on informant, 22% to 26% of the sample demonstrated clinically elevated internalizing problems. In multiple and binary logistic regression models, only parent psychiatric symptoms consistently provided unique prediction of teen internalizing symptoms. For maternal but not paternal report, female gender was associated with greater internalizing problems. CONCLUSION: Parent and teen emotional problems are associated following adolescent TBI. Possible reasons for this relationship, including the effects of TBI on the family unit, are discussed.
Assuntos
Comportamento do Adolescente/psicologia , Lesões Encefálicas/psicologia , Transtornos do Comportamento Infantil/epidemiologia , Transtornos Mentais/diagnóstico , Pais/psicologia , Adolescente , Adulto , Lesões Encefálicas/diagnóstico , Lesões Encefálicas/reabilitação , Criança , Transtornos do Comportamento Infantil/etiologia , Transtornos do Comportamento Infantil/fisiopatologia , Estudos de Coortes , Relações Familiares , Feminino , Humanos , Incidência , Escala de Gravidade do Ferimento , Controle Interno-Externo , Masculino , Transtornos Mentais/epidemiologia , Testes Neuropsicológicos , Prognóstico , Psicometria , Medição de RiscoRESUMO
We describe a non-invasive method for profiling selected hormones, pharmaceuticals and personal care products (PPCPs) in killer whales (Orcinus orca) based on analysis of faecal samples by liquid chromatography tandem mass spectrometry (LC-MS/MS). The method targets 21 compounds of interest including glucocorticoids, mineralocorticoids, androgens, estrogens, progestogens, selective serotonin uptake inhibitors and an antibacterial/antifungal agent. This method is suitable for routine simultaneous determination of target compounds in killer whale faecal samples as well as validation of immunoassays for the detection and measurement of steroid hormones in faeces. The optimized method involves extraction of freeze-dried faecal material with reagent alcohol and water followed by isolation of the analytes using solid phase extraction with hydrophilic-lipophilic balance cartridges and liquid-liquid extraction with methyl tertiary-butyl ether. Reconstituted extracts were analysed by LC-MS/MS using an electrospray ionization interface. Method limit of quantification ranged from 0.06 to 45.2 ng/g in freeze-dried faecal samples. Except for sertraline, triclosan and estradiol (which was not recovered at the lowest spiked concentration), average intra- and inter-day precisions were within 10%, and average recoveries were between 89.3% and 129.3%, for faecal samples spiked with 5.3, 26.7 or 133 ng/g of each analyte. The method was applied successfully to the analysis of hormones and PPCPs in whale faeces during which 17α-hydroxyprogesterone, a common intermediate in steroid biosynthesis that cross-reacts with precursors and sulphated conjugates in immunoassays, was identified and quantified in all samples.
RESUMO
The breakdown product of the rubber tire antioxidant N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine-quinone (6PPD)-6-PPD-quinone has been strongly implicated in toxic injury and death in coho salmon (Oncorhynchus kisutch) in urban waterways. Whereas recent studies have reported a wide range of sensitivity to 6PPD-quinone in several fish species, little is known about the risks to Chinook salmon (Oncorhynchus tshawytscha), the primary prey of endangered Southern Resident killer whales (Orcinus orca) and the subject of much concern. Chinook face numerous conservation threats in Canada and the United States, with many populations assessed as either endangered or threatened. We evaluated the acute toxicity of 6PPD-quinone to newly feeding (~3 weeks post swim-up) juvenile Chinook and coho. Juvenile Chinook and coho were exposed for 24 h under static conditions to five concentrations of 6PPD-quinone. Juvenile coho were 3 orders of magnitude more sensitive to 6PPD-quinone compared with juvenile Chinook, with 24-h median lethal concentration (LC50) estimates of 41.0 and more than 67 307 ng/L, respectively. The coho LC50 was 2.3-fold lower than what was previously reported for 1+-year-old coho (95 ng/L), highlighting the value of evaluating age-related differences in sensitivity to this toxic tire-related chemical. Both fish species exhibited typical 6PPD-quinone symptomology (gasping, increased ventilation, loss of equilibrium, erratic swimming), with fish that were symptomatic generally exhibiting mortality. The LC50 values derived from our study for coho are below concentrations that have been measured in salmon-bearing waterways, suggesting the potential for population-level consequences in urban waters. The higher relative LC50 values for Chinook compared with coho merits further investigation, including for the potential for population-relevant sublethal effects. Environ Toxicol Chem 2023;42:815-822. © 2023 His Majesty the King in Right of Canada and The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. Reproduced with the permission of the Minister of Fisheries and Oceans Canada.
Assuntos
Benzoquinonas , Estágios do Ciclo de Vida , Fenilenodiaminas , Salmão , Animais , Canadá , Oncorhynchus kisutch/crescimento & desenvolvimento , Oncorhynchus kisutch/fisiologia , Salmão/crescimento & desenvolvimento , Salmão/fisiologia , Estágios do Ciclo de Vida/efeitos dos fármacos , Fenilenodiaminas/toxicidade , Benzoquinonas/toxicidade , Dose Letal MedianaRESUMO
Very high levels of industrial contaminants in St. Lawrence Estuary (SLE) beluga whales represent one of the major threats to this population classified as endangered under the Species at Risk Act in Canada. Elevated concentrations of short-chained chlorinated paraffins (SCCPs) were recently reported in blubber of adult male SLE belugas. Recent regulations for SCCPs in North America, combined with their replacement by medium- (MCCPs) and long-chained chlorinated paraffins (LCCPs), highlight the importance of tracking this toxic chemical class. The objectives of this study were to evaluate (1) levels and profiles of chlorinated paraffins (CPs) in samples obtained from carcasses of adult male, adult female, juvenile, newborn, and fetus beluga, and (2) trends in adult male belugas between 1997 and 2018. Factors potentially influencing CP temporal trends such as age, feeding ecology and sampling year were also explored. SCCPs dominated (64 to 100%) total CP concentrations across all age and sex classes, MCCPs accounted for the remaining proportion of total CPs, and LCCPs were not detected in any sample. The chlorinated paraffin homolog that dominated the most in beluga blubber was C12Cl8. Adult male SCCP concentrations from this study were considerably lower (> 2000-fold) than those recently reported in Simond et al. (2020), likely reflecting a previously erroneous overestimate due to the lack of a suitable analytical method for SCCPs at the time. Both SCCPs and total CPs declined over time in adult males in our study (rate of 1.67 and 1.33% per year, respectively), presumably due in part to the implementation of regulations in 2012. However, there is a need to better understand the possible contribution of a changing diet to contaminant exposure, as stable isotopic ratios of carbon also changed over time.
Assuntos
Beluga , Hidrocarbonetos Clorados , Poluentes Químicos da Água , Animais , Feminino , Masculino , China , Dieta , Monitoramento Ambiental/métodos , Estuários , Hidrocarbonetos Clorados/análise , Parafina/análise , Poluentes Químicos da Água/análiseRESUMO
Environmental change in the Arctic has impacted the composition and structure of marine food webs. Tracking feeding ecology changes of culturally-valued Arctic char (Salvelinus alpinus) and ringed seals (Pusa hispida) can provide an indication of the ecological significance of climate change in a vulnerable region. We characterized how changes in sea ice conditions, sea surface temperature (SST), and primary productivity affected the feeding ecology of these two keystone species over a 13- and 18-year period, respectively, in northern Labrador, Canada. Arctic char fed consistently on pelagic resources (δ13C) but shifted over time to feeding at a higher trophic level (δ15N) and on more marine/offshore resources (δ34S), which correlated with decreases in chlorophyll a concentration. A reduction in Arctic char condition factor and lipid content was associated with higher trophic position. Ringed seals also shifted to feeding at a higher trophic level, but on more pelagic resources, which was associated with lower SST and higher chlorophyll a concentrations. Years with abnormally high SSTs and reduced sea ice concentrations resulted in large isotopic niche sizes for both species, suggesting abrupt change can result in more variable feeding. Changes in abundance and distribution of species long valued by the Inuit of Labrador could diminish food security.
Assuntos
Caniformia , Focas Verdadeiras , Animais , Clorofila A , Canadá , Mudança Climática , Cadeia AlimentarRESUMO
The tire-derived contaminant N-(1,3-dimethylbutyl)-N'-phenyl-p-phenylenediamine quinone (6-PPDQ) was recently identified as a potent toxin to coho salmon (Oncorhynchus kisutch). Studies investigating 6-PPDQ have employed solid-phase extraction (SPE) or liquid-liquid extraction (LLE) with liquid chromatography-mass spectrometry (LC-MS), providing excellent sensitivity and selectivity. However, cleanup and pre-enrichment steps (SPE/LLE) followed by chromatographic separation can be time- and cost-intensive, limiting sample throughput. The ubiquitous distribution of 6-PPDQ necessitates numerous measurements to identify hotspots for targeted mitigation. We recently developed condensed phase membrane introduction mass spectrometry (CP-MIMS) for rapid 6-PPDQ analysis (2.5 min/sample), with a simple workflow and low limit of detection (8 ng/L). Here, we describe improved quantitation using isotopically labeled internal standards and inclusion of a suite of PPDQ analogues. A low-cost autosampler and data processing software were developed from a three-dimensional (3D) printer and Matlab to fully realize the high-throughput capabilities of CP-MIMS. Cross-validation with a commercial LC-MS method for 10 surface waters provides excellent agreement (slope: 1.01; R2 = 0.992). We employ this analytical approach to probe fundamental questions regarding sample stability and sorption of 6-PPDQ under lab-controlled conditions. Further, the results for 192 surface water samples provide the first spatiotemporal characterization of PPDQs on Vancouver Island and the lower mainland of British Columbia.
RESUMO
Background: Many health care organizations offer pediatric infusions in outpatient infusion centers or, as in our organization, in a hospital-based outpatient Pediatric Infusion Therapy Center (PITC). When restrictions related to the COVID-19 pandemic decreased our PITC appointment capacity by 40%, other patient and family satisfaction issues were exacerbated. We implemented a new approach to pediatric infusions with the aim of improving patient and family satisfaction and reducing the amount of time in an appointment itinerary without negatively affecting patient safety. Methods: Our team used a phased approach to pilot the administration of short chemotherapy infusions in the same outpatient clinic examination rooms where consultation and routine office visits were conducted. Patients saw their specialist for an examination and, if clinically indicated, their infusion was administered in the same room. Appointment itineraries were then completed. The team tracked efficiency, satisfaction, and safety metrics related to the new process. Results: All efficiency metrics improved. No harm came to the 49 unique patients who received a total of 184 infusions. Patient appointment itineraries were shortened by an average of 1.03â hr. Satisfaction survey responses indicated a clear preference (93%) for the new process. Discussion: The novel approach of offering short infusions in outpatient clinic examination rooms provides an opportunity to ease capacity constraints and further increase patient and family satisfaction. This method may be especially helpful for health care organizations when external influences (e.g., lack of physical space, challenging patient volumes, and pandemics) necessitate a change.