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1.
Prev Med ; 159: 107056, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35452712

RESUMO

Teenagers' vaccination has become crucial to limit the COVID-19 transmission in the population. To increase the vaccination rate of this age group, a school-based vaccination campaign was launched in Québec, Canada from June 7 to 18, 2021. This study aimed to analyze trajectories of vaccination coverage over time among students attending 37 high schools. The study explored whether school-based vaccination campaigns contributed to the progression of the vaccination coverage and attenuated disparities in vaccination coverage across schools. On average, first dose coverage quickly increased from 30.6% to 81.5% between June 6 and 18, 2021, after the launch of the campaign. As of August 13, 2021, first dose coverage had reached 87.9% and 64.9% for the second dose coverage. Public schools with poorer student populations had 6.5 points of percentage lower first dose vaccination rates (95%CI 0.3%; 12.6%) compared to other schools. A higher level of concern related to the pandemic among students was associated with a 4.3 points of percentage increased coverage (95%CI 0.7%; 8.0%). The initial uneven distribution in first dose coverage decreased dramatically by the end of the campaign. Similar trends were observed for the second dose, although between schools' inequality at the end of the period of observation was significantly larger. The school-based vaccination campaign might have initially contributed to a prompt rise in vaccination coverage and helped the disadvantaged schools to reach similar vaccination coverage as seen in other schools. In addition to being an efficient way to achieve rapidly high vaccination coverage, the school-based approach might contribute to increase equity in vaccination distribution.


Assuntos
COVID-19 , Cobertura Vacinal , Adolescente , COVID-19/prevenção & controle , Humanos , Quebeque , Instituições Acadêmicas , Vacinação
2.
Arch Environ Contam Toxicol ; 82(4): 581-591, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35347351

RESUMO

Per- and polyfluoroalkyl substances (PFASs) are anthropogenic substances that are very stable in the receiving environment. Legacy perfluoroalkane sulfonates (PFSAs) and perfluoroalkyl carboxylic acids (PFCAs) are especially persistent and resistant to typical environmental degradation processes and therefore are distributed across all trophic levels and environmental compartments (soil, air, water). Since most uses of perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), and LC-long-chain PFCAs are banned in Canada, alternative PFASs have been in use for a number of years. Twenty-nine sites across Canada were sampled for PFASs to determine concentrations and trends. Overall, 13 PFASs were measured in 566 Canadian freshwater samples from 2013 to 2020 with a range from below the detection limit (LOD range: 0.4-1.6 ng/L) of the laboratory to a maximum of 138 ng/L (for PFBS). While PFOS and PFOA concentrations are declining significantly over time, other compounds such as PFPeA and PFBA have increased significantly over 2013-2020. Overall, the range of concentrations found in this study was similar to that of other Canadian and international studies. However, this study also found a higher frequency of detections of the replacement PFASs than that of the other, older, Canadian studies.


Assuntos
Ácidos Alcanossulfônicos , Fluorocarbonos , Poluentes Químicos da Água , Ácidos Alcanossulfônicos/análise , Canadá , Monitoramento Ambiental , Fluorocarbonos/análise , Água Doce , Solo , Poluentes Químicos da Água/análise
3.
Arch Environ Contam Toxicol ; 80(2): 319-330, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33432443

RESUMO

Nonylphenol, octylphenol, and nonylphenol ethoxylates are manmade compounds that are only discharged in the environment due to anthropogenic activities. The objectives of this study were to determine the current concentrations of these substances in the Canadian freshwater environment and to determine if past regulatory actions were beneficial to the environment. Freshwater samples (n = 241) were collected and analysed for 4-nonylphenols (NP), nonylphenol monoethoxylate (NP1EO), nonylphenol diethoxylate (NP2EO), and octylphenols at 35 sites in Canada from 2014 to 2019 with individual compound concentrations ranging from 1.29 to 477.22 ng/L. In addition, 18-65% of the samples were reported to be under the laboratory detection limit, depending on the compound. Sampling sites were categorised into five groups based on the dominant activities present upstream in their watersheds: mixed use sites; municipal waste water treatment plant (MWWTP)-associated sites; textile mill-associated sites; urban; and reference sites. All four compounds in the study were detected more frequently in urban and MWWTP-associated sites than at other locations. Additionally, there is a statistically significant (p < 0.05) downward temporal trend in NP concentrations in Canadian surface waters from 2014 to 2019. There were no exceedances of the Canadian Water Quality Guideline of 1000 ng/L.


Assuntos
Monitoramento Ambiental , Fenóis/análise , Poluentes Químicos da Água/análise , Canadá , Etilenoglicóis , Água Doce/análise , Águas Residuárias/análise , Purificação da Água
4.
Sci Total Environ ; 755(Pt 2): 142472, 2021 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-33059142

RESUMO

Bisphenol A (BPA) is an industrial chemical that has been identified by some jurisdictions as an environmental concern. In 2010, Canada concluded that this substance posed a risk to the environment and human health, and implemented actions to reduce its concentrations in the environment. To support these activities, a multimedia analysis of BPA in the Canadian environment was conducted to evaluate spatial and temporal trends, and to infer mechanisms influencing the patterns. BPA was consistently detected in wastewater and biosolids across Canadian wastewater treatment plants (WWTPs) and in landfill leachate. In addition, BPA concentrations were significantly higher in surface water downstream compared to upstream of WWTPs in three of five urban areas evaluated. However, application of biosolids to Canadian agricultural fields did not contribute to elevated BPA concentrations in soil, earthworms, and European Starling (Sturnus vulgaris) plasma one and two years post-treatment. Spatial trends of BPA concentrations in surface water and sediment are influenced by human activity, with higher concentrations typically found downstream of industrial sources and WWTPs in urban areas. BPA was detected in bird plasma at locations impacted by WWTPs and landfills. However, spatial trends in birds were less clear and may have been confounded by metabolic biotransformation. In terms of temporal trends, BPA concentrations in surface water decreased significantly at 10 of 16 monitoring sites evaluated between 2008 and 2018. In contrast, recent temporal trends of BPA in six sediment cores were variable, which may be a result of biotransformation of the flame retardant tetrabromobisphenol A to BPA. Overall, our study provides evidence that Government of Canada actions have been generally successful in reducing BPA concentrations in the Canadian environment. Our results indicate that long-term monitoring programs using surface water are more effective than other media for tracking and understanding future environmental trends of BPA.


Assuntos
Monitoramento Ambiental , Poluentes Químicos da Água , Animais , Compostos Benzidrílicos/análise , Canadá , Humanos , Multimídia , Fenóis , Poluentes Químicos da Água/análise
5.
Arch Environ Contam Toxicol ; 79(1): 12-22, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32447405

RESUMO

This study measured both nutrient and pesticide concentrations at up to 13 different freshwater stream sites in New Brunswick, Nova Scotia and Prince Edward Island between 2013 and 2018. Up to 62 different pesticides were analysed in 248 discreet samples. A large majority of pesticides were below the detection limit of the laboratory while seven pesticides had at least 20% or more detections throughout the years of this study. The four pesticides that had the highest frequency of detection were the insecticides chlorantraniliprole, clothianidin, imidacloprid, and thiamethoxam of which the last three are categorised as neonicotinoid insecticides.


Assuntos
Monitoramento Ambiental/métodos , Praguicidas/análise , Rios/química , Poluentes Químicos da Água/análise , Canadá , Guanidinas/análise , Neonicotinoides/análise , Nitrocompostos/análise , Análise Espaço-Temporal , Tiametoxam/análise , Tiazóis/análise
6.
Neurooncol Adv ; 2(1): vdaa012, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32161911

RESUMO

BACKGROUND: The aim of this study is to present a national surveillance report on pediatric central nervous system (CNS) tumors in Canada during the period between 2001 and 2015. METHODS: All pediatric patients with a diagnosis of primary CNS tumors were collected by the Cancer in Young People in Canada (CYP-C) surveillance system that includes every patient less than 15 years of age with a tumor seen in one of the 17 pediatric oncology centres in Canada. This registry included malignant and benign CNS tumors. We calculated the age-adjusted incidence rates (AAIRs) per 100 000 person-years for CNS tumors overall and by age group, major histology subgroups, and geographical distribution over the country. RESULTS: Overall, 3306 patients less than 15 years old had been diagnosed with a CNS tumor in Canada in 2001-2015 with a 1.23:1 male to female ratio. The overall AAIR is 3.80. The three most frequent groups of tumors were low-grade gliomas (36.4%), high-grade gliomas (22.3%), and embryonal tumors (18.7%) with incidence rates of 1.41, 0.86, and 0.72 per 100 000 person-years, respectively. The incidence rate of pediatric CNS tumors is stable during the period 2001-2015 in Canada and no significant differences were seen between malignant and benign tumors over the country. CONCLUSIONS: These data represent all the pediatric patients 0-14 years old with a CNS tumor in the Canadian population. Incidence rates by age group, sex, and subgroups of tumors are similar to those seen in the literature.

7.
Arch Environ Contam Toxicol ; 78(4): 568-578, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32107598

RESUMO

Bisphenol A (BPA) is a manmade chemical that is only found in the environment due to anthropogenic activities. A total of 1150 surface freshwater samples were collected and analysed for BPA at 44 sampling sites in Canada from 2012 to 2018. The resultant concentrations ranged from 3.05 to 1888.51 ng/L. In addition, 64% of the samples were reported to be under the detection limit of the laboratory. In comparison, the Federal Environmental Quality Guideline for the protection of aquatic life is 3500 ng/L. Sampling sites were categorised into four groups based on the dominant activities present upstream in their watersheds: reference sites, mixed use sites, urban sites, and municipal waste water treatment plants (MWWTP) associated sites. Based on the results of this study, detections of BPA in water samples were more frequent in urban and MWWTP-associated sites. Additionally, there does not seem to be a statistically significant temporal (upward or downward) or spatial trend in BPA concentrations in Canadian surface waters from 2012 to 2018 only. Overall, Canadian BPA results are of similar concentrations to that of other countries in Asia and Europe.


Assuntos
Compostos Benzidrílicos/análise , Monitoramento Ambiental/métodos , Água Doce/química , Fenóis/análise , Poluentes Químicos da Água/análise , Canadá , Cidades , Análise Espaço-Temporal , Águas Residuárias/química , Purificação da Água
8.
Arch Environ Contam Toxicol ; 76(2): 231-245, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30361942

RESUMO

Triclosan is widely used in personal care products (skin creams, toothpastes, soaps, deodorants, body spray) and cleaning products (dishwashing detergent and all-purpose cleaners) (Halden in Environ Sci Technol 48:3603-3611, 2014). In 2001, it was selected for screening-level risk assessment under the Canadian Environmental Protection Act (HC and EC in Preliminary assessment. Triclosan. Chemical abstracts Service Number 3380-34-5, 2012. http://www.ec.gc.ca/ese-ees/default.asp?lang=En&n=6EF68BEC-1 ), and its physicochemical and toxicological characteristics indicate that there may be a risk to aquatic environments due to releases of the chemical in Canada. A surveillance initiative across Canada has included sampling at 44 sites from July 2012 to March 2018. Triclosan was detected in 226 of 918 samples; concentrations ranged from less than 6 to 874 ng L-1, and the detections averaged 54.23 ng L-1 (standard deviation; 97.6 ng L-1). However, using the entire dataset (including censored data estimated with the Kaplan-Meier model), the mean triclosan concentration was 17.95 ng L-1, and the standard deviation was 52.84 ng L-1. Three samples at Wascana Creek (downstream), Saskatchewan, had concentrations above the Federal Environmental Quality Guidelines of 470 ng L-1, indicating a potential risk to the aquatic ecosystem. In this study, triclosan in samples collected downstream from municipal wastewater treatment plant discharges usually demonstrated higher concentrations than upstream samples. Based on the results of this study, it is hypothesized that triclosan concentration have fluctuated between years of this study but not in an overall or significant increase or decreasing trend. Triclosan concentrations and detections also are more prevalent in urban than in rural or mixed development rivers. Performance evaluation of triclosan concentrations in the Canadian environment is scheduled to be reassessed by 2024. Therefore, a 3-year sampling program should be in place across Canada by 2021.


Assuntos
Água Doce/análise , Triclosan/análise , Poluentes Químicos da Água/análise , Canadá , Monitoramento Ambiental
9.
PLoS One ; 12(3): e0174417, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28358819

RESUMO

This paper reviews studies of the validity of commercially available business (CAB) data on food establishments ("the foodscape"), offering a meta-analysis of characteristics associated with CAB quality and a case study evaluating the performance of commonly-used validity indicators describing the foodscape. Existing validation studies report a broad range in CAB data quality, although most studies conclude that CAB quality is "moderate" to "substantial". We conclude that current studies may underestimate the quality of CAB data. We recommend that future validation studies use density-adjusted and exposure measures to offer a more meaningful characterization of the relationship of data error with spatial exposure.


Assuntos
Comércio , Comportamento Alimentar , Preferências Alimentares , Abastecimento de Alimentos , Características de Residência
10.
Public Health Nutr ; 20(5): 927-937, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-27881202

RESUMO

OBJECTIVE: We investigated the association between junk food consumption at lunchtime (JCL) and fast-food outlet access near school among secondary-school children in Quebec. DESIGN: A geographic information system database was used to characterize the food environment around a sub-sample of 374 public schools in which 26 655 students were enrolled. The outcome variable was JCL during the previous week, dichotomized into low JCL (none or once) v. high JCL (twice or more). Access to fast-food outlets near school was assessed using an existing database of fast-food outlets in Quebec. Covariates included student (age, sex and self-rated perceived health), family (familial status and parental education) and school (urban/rural status and deprivation) variables. Hierarchical logistic regression models were employed for analyses using PROC GLIMMIX of SAS version 9.3. SETTING: Province of Quebec, Canada. SUBJECTS: We used data from the Quebec Health Survey of High School Students (QHSHSS) 2010-11, a survey of secondary-school Quebec students. RESULTS: Exposure to two or more fast-food outlets within a radius of 750 m around schools was associated with a higher likelihood of excess JCL (OR=1·50; 95 % CI 1·28, 1·75), controlling for the characteristics of the students, their families and their schools. CONCLUSIONS: The food environment surrounding schools can constitute a target for interventions to improve food choices among secondary-school children living in the province of Quebec. Transforming environments around schools to promote healthy eating includes modifying zoning regulations that restrict access to fast-food outlets around schools.


Assuntos
Fast Foods , Serviços de Alimentação , Características de Residência , Instituições Acadêmicas , Estudantes , Adolescente , Criança , Comportamento de Escolha , Estudos Transversais , Dieta , Feminino , Preferências Alimentares , Humanos , Masculino , Avaliação Nutricional , Inquéritos Nutricionais , Quebeque , Fatores Socioeconômicos
11.
J Environ Public Health ; 2016: 1416384, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27752265

RESUMO

The purpose of the research was to explore the associations between the characteristics of schools' vicinity and the risk of sugar sweetened beverage (SSB) consumption in elementary students. Findings exposed an important variation in student's SSB consumption between schools. Schools with a lower socioeconomic status or in a densely built environment tend to have higher proportion of regular SSB drinkers. These characteristics of the school's vicinity partly explained the variation observed between them. We estimated that a student moving to a school with a higher proportion of SSB drinkers may increase his/her chances by 52% of becoming a daily consumer. Important changes in dietary preferences can occur when children are in contact with a new social environment. Findings also support the idea that dietary behaviors among children result from the complex interactions between biological, social, and environmental factors.


Assuntos
Bebidas/estatística & dados numéricos , Ingestão de Líquidos , Meio Social , Estudantes/estatística & dados numéricos , Criança , Feminino , Humanos , Masculino , Quebeque , Instituições Acadêmicas , Edulcorantes
12.
Bull Environ Contam Toxicol ; 94(4): 444-7, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25687360

RESUMO

Formaldehyde is used in freshwater aquaculture facilities in the Maritimes region of Canada to prevent external parasites and is discharged without treatment to freshwater receiving environments. In this study, formaldehyde was measured at effluent outfalls and 100 m downstream of four land based aquaculture facilities at various post-treatment time intervals. Concentrations of formaldehyde ranged from 0.2 to 7.1 mg/L. Based on Environment Canada's environmental no effect value, all of the samples show a potential risk to aquatic life. Furthermore, based on a chronic aquatic life water quality criterion of 1.61 mg/L all but two of the samples had concentrations considered to be toxic to aquatic life. An acute water quality criteria was only exceeded once in all of the environmental measurements of formaldehyde. These results lead us to hypothesize that the discharge of formaldehyde from land-based facilities may cause adverse chronic impacts.


Assuntos
Aquicultura , Formaldeído/análise , Água Doce/química , Poluentes Químicos da Água/análise , Qualidade da Água , Canadá , Medição de Risco
13.
Bull Environ Contam Toxicol ; 89(3): 547-50, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22801927

RESUMO

This study investigated the occurrence of oxytetracycline (OTC) and emamectin benzoate (EB) in sediments located near the effluent outfall from four freshwater aquaculture facilities in Atlantic Canada. While two facilities had no detectable concentrations of EB or OTC, two facilities had detectable concentrations of one or both of these chemicals. Concentrations ranged from <0.05-18 mg/kg to <0.01-2.5 mg/kg for OTC and EB respectively. Although these values could not be compared with freshwater toxicant values, some of the concentrations of EB and OTC detected were higher than LC(50) values calculated for marine invertebrates. OTC concentrations measured in this study are also of a magnitude which has been known to produce resistant bacteria.


Assuntos
Aquicultura , Sedimentos Geológicos/química , Ivermectina/análogos & derivados , Oxitetraciclina/análise , Canadá , Água Doce , Ivermectina/análise
14.
Arch Environ Contam Toxicol ; 63(1): 45-53, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22311548

RESUMO

Benthic invertebrate communities have been known to change due to impacts from nutrient-rich industrial outputs, such as those from pulp and paper, sewage-treatment plants, or aquaculture. Fish-processing plants have been recognized as contributors of large volumes of nutrient rich effluent to marine and estuarine environments, but their effect on benthic invertebrate communities is unknown. Benthic invertebrates and sediment samples were obtained from marine sampling stations at 0-, 10-, 30-, and 100-m distances from two fish-processing outfalls in Atlantic Canada. Sediment grain size, total organic carbon (TOC), ammonia, sulphide, and redox, as well as invertebrate abundance, density, taxa richness, Simpson's Inverse Diversity Index, Bray-Curtis Index of (%) Similarity, and the AZTI marine biotic index (AMBI), were determined for all sampling sites. Results from this study illustrate that taxa richness and density significantly increased as distance from the outfall discharge increased. In our study, TOC was only significantly correlated to AMBI but not to the other benthic invertebrate assemblage descriptors calculated in this study (invertebrate density, taxa richness, Simpson's Inverse Diversity Index). The study results suggest that taxa richness and density may be affected by effluent from fish-processing plants.


Assuntos
Aquicultura/métodos , Ecossistema , Monitoramento Ambiental/métodos , Invertebrados , Poluentes Químicos da Água/análise , Animais , Peixes , Tecnologia de Alimentos/métodos , Sedimentos Geológicos/análise , Resíduos Industriais/análise , Invertebrados/efeitos dos fármacos , Novo Brunswick , Medição de Risco , Rios/química , Poluentes Químicos da Água/toxicidade
15.
Arch Environ Contam Toxicol ; 61(3): 472-81, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21221964

RESUMO

Metals that originate from coal-combustion residue (ash) deposited in water-filled lagoons are eventually released into the environment. This study measured metal concentrations in sediment and fish obtained in the vicinity of two coal-combustion ash-lagoon outfalls on the East River (Nova Scotia) and Grand Lake (New Brunswick), Canada. Of the 34 metals analysed, this study demonstrated that sediment in the immediate vicinity of the ash lagoon discharge in New Brunswick had statistically significant greater concentrations of thallium, arsenic, and antimony than did the sediment obtained from background areas. Tissue arsenic concentrations were increased in fish obtained near the lagoon discharge in New Brunswick but not statistically greater than that of fish obtained from background areas. Neither sediment nor fish obtained near the ash-lagoon discharge in Nova Scotia had significantly greater concentrations of any of the metals measured.


Assuntos
Peixes , Sedimentos Geológicos/análise , Metais/análise , Poluentes Químicos da Água/análise , Animais , Carvão Mineral/análise , Monitoramento Ambiental/métodos , Sedimentos Geológicos/química , Lagos , Novo Brunswick , Nova Escócia , Centrais Elétricas , Medição de Risco , Rios/química
16.
Arch Environ Contam Toxicol ; 61(3): 368-75, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21222116

RESUMO

Comparative toxicity testing was performed on selected materials that may be used in aquatic construction projects. The tests were conducted on the following materials: (1) untreated wood species (hemlock [Tsuga ssp], Western red cedar (Thuja plicata), red oak [Quercus rubra], Douglas fir [Pseudotsuga menziesii], red pine [Pinus resinosa], and tamarack [Larix ssp]); (2) plastic wood; (3) Ecothermo wood hemlock stakes treated with preservatives (e.g., chromated copper arsenate [CCA], creosote, alkaline copper quaternary [ACQ], zinc naphthenate, copper naphthenate, and Lifetime Wood Treatment); (4) epoxy-coated steel; (5) hot-rolled steel; (6) zinc-coated steel; and (7) concrete. Those materials were used in acute lethality tests with rainbow trout, Daphnia magna, Vibrio fischeri and threespine stickleback. The results indicated the following general ranking of the materials (from the lowest to highest LC(50) values); ACQ > creosote > zinc naphthenate > copper naphthenate > CCA (treated at 22.4 kg/m(3)) > concrete > red pine > western red cedar > red oak > zinc-coated steel > epoxy-coated steel > CCA (6.4 kg/m(3)). Furthermore, the toxicity results indicated that plastic wood, certain untreated wood species (hemlock, tamarack, Douglas fir, and red oak), hot-rolled steel, Ecothermo wood, and wood treated with Lifetime Wood Treatment were generally nontoxic to the test species.


Assuntos
Materiais de Construção/toxicidade , Testes de Toxicidade/métodos , Madeira/química , Aliivibrio fischeri/efeitos dos fármacos , Animais , Arseniatos/análise , Arseniatos/toxicidade , Ácidos Carboxílicos/análise , Ácidos Carboxílicos/toxicidade , Creosoto/análise , Creosoto/toxicidade , Daphnia/efeitos dos fármacos , Monitoramento Ambiental/métodos , Larix/química , Pinus/química , Plásticos/análise , Plásticos/toxicidade , Pseudotsuga/química , Quercus/química , Thuja/química , Tsuga/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
17.
Bull Environ Contam Toxicol ; 85(2): 170-3, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20652219

RESUMO

The total concentration of PBDEs in the wastewater from fish plants ranged from 82 to 35,055 pg/L which was higher than ambient concentrations measured in surface water samples in North America (6-158 pg/L). Based on the concentration of PDBES in the effluent, calculated daily discharge of PBDEs into the environment ranged from 0.03 to 13.34 g per day. The concentrations of PBDEs in the solid fraction of the effluent from this study has been calculated to range from 0.78 ng/g for scallop, to 3,505 ng/g for cod with herring having the second highest concentration of 1,534 ng/g.


Assuntos
Indústria de Processamento de Alimentos , Éteres Difenil Halogenados/análise , Resíduos Industriais/análise , Alimentos Marinhos/análise , Esgotos/química , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Contaminação de Alimentos/análise
18.
Bull Environ Contam Toxicol ; 84(3): 322-5, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20041228

RESUMO

Since polybrominated biphenyl ethers (PBDEs) are known to be present in various species of fish, it is likely that fish processing effluent would contain significant amount of PBDEs. The purpose of this study was to determine the PBDE concentrations in sediments located near fish plant effluent outfalls. The range of concentrations of PBDEs in marine sediments in Canada published in the literature was very similar to the results obtained in this study (0.015-5.12 ng/g, dry weight). The concentrations measured in this study for all three technical mixtures (2.78 x 10(-3), 1.92 x 10(-3) and 2.02 x 10(-3) mg/kg, respectively) were all below known toxicity thresholds (0.031, 9.1 and 76 mg/kg, respectively).


Assuntos
Aquicultura , Sedimentos Geológicos/química , Éteres Difenil Halogenados/análise , Canadá
19.
Arch Environ Contam Toxicol ; 56(3): 389-96, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18752017

RESUMO

There are over 1100 fish-processing plants in Canada and the majority of them discharge untreated effluents directly to marine or estuarine receiving environments. The purpose of this study was to evaluate chemical and toxicological characteristics of sediments near fish-processing plant effluent discharges to assess potential impacts of seafood-processing effluents on receiving environments. Eighteen sediment samples were collected near effluent discharges of six seafood-processing plant outfalls in New Brunswick, Canada in the winter of 2006. Ammonia levels ranged from <0.2 to 3480 microg/g, sulfide levels ranged from <0.4 to 6970 microg/g, and redox ranged from -255 to 443 mV. Only one sample had a Microtox Solid-Phase Test IC(50) value below 1000 mg/kg, whereas three samples caused greater than 30% reduction to amphipod survival. Redox, sulfide, and ammonia concentrations were all found to be significantly related to both Eohaustorius estuarius survival and Microto (Vibrio fischeri) IC(50). An increase in sulfide (R (2) = 0.584; 0.750) and ammonia (R (2) = 0.478; 0.552) and a decrease in redox (R (2) = 0.485; 0.651) were associated with an increase in toxicity to E. estuarius and Microtox, respectively. The highest toxicity to both test organisms, and the most contaminated sediments based on physical/chemical characteristics measured, was observed in samples from Blacks Harbour.


Assuntos
Indústria de Processamento de Alimentos , Sedimentos Geológicos/análise , Resíduos Industriais/efeitos adversos , Alimentos Marinhos , Poluentes Químicos da Água/toxicidade , Amônia/análise , Amônia/toxicidade , Animais , Resíduos Industriais/análise , Dose Letal Mediana , Análise de Regressão , Sulfetos/análise , Sulfetos/toxicidade , Testes de Toxicidade , Poluentes Químicos da Água/análise
20.
J Can Dent Assoc ; 72(4): 325-9, 2006 May.
Artigo em Inglês | MEDLINE | ID: mdl-16684476

RESUMO

Orofacial granulomatosis comprises a group of diseases characterized by noncaseating granulomatous inflammation affecting the soft tissues of the oral and maxillofacial region. The most common clinical presentation is persistent swelling of one or both lips. It is important to establish the diagnosis accurately because this condition is sometimes a manifestation of Crohn's disease or sarcoidosis. This article describes 2 cases of orofacial granulomatosis, in one of which the condition was a manifestation of Crohn"s disease. The diagnostic approach to and the treatment of orofacial granulomatosis are reviewed.


Assuntos
Doença de Crohn/complicações , Granulomatose Orofacial/patologia , Doenças da Boca/patologia , Corticosteroides/administração & dosagem , Adulto , Anti-Inflamatórios/administração & dosagem , Doença de Crohn/diagnóstico , Diagnóstico Diferencial , Feminino , Granulomatose Orofacial/tratamento farmacológico , Granulomatose Orofacial/etiologia , Humanos , Injeções Intravenosas , Lábio/patologia , Pessoa de Meia-Idade , Doenças da Boca/etiologia , Mucosa Bucal/patologia
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