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1.
Sci Total Environ ; 753: 142185, 2021 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-33207481

RESUMEN

Dioxins have been an inconvenience to the Baltic Sea ecosystem for decades. Although the concentrations in the environment and biota have continuously decreased, dioxins still pose a risk to human health. The risk and its formation vary in different parts of the Baltic Sea, due to variability in the environmental and societal factors affecting it. This paper presents a systematic literature review and knowledge synthesis about the regional dioxin risk formation in four sub-areas of the Baltic Sea and evaluates, whether systemic approach changes our thinking about the risk and its effective management. We studied the dioxin flux from atmospheric deposition to the Baltic Sea food webs, accumulation to two commercially and culturally important fish species, Baltic herring (Clupea harengus membras) and Baltic salmon (Salmo salar), and further to risk group members of four Baltic countries. Based on 46 studies, we identified 20 quantifiable variables and indexed them for commensurable regional comparison. Spatial differences in dioxin pollution, environmental conditions, food web dynamics, and the following dioxin concentrations in herring and salmon, together with fishing and fish consumption, affect how the final health risk builds up. In the southern Baltic Sea, atmospheric pollution levels are relatively high and environmental processes to decrease bioavailability of dioxins unfavorable, but the growth is fast, which curb the bioaccumulation of dioxins in the biota. In the North, long-range atmospheric pollution is minor compared to South, but the local pollution and slower growth leads to higher bioaccumulation rates. However, based on our results, the most remarkable differences in the dioxin risk formation between the areas arise from the social sphere: the emissions, origin of national catches, and cultural differences in fish consumption. The article suggests that acknowledging spatial characteristics of socio-ecological systems that generate environmental risks may aid to direct local focus in risk management.


Asunto(s)
Dioxinas , Dibenzodioxinas Policloradas , Contaminantes Químicos del Agua , Animales , Países Bálticos , Dioxinas/análisis , Ecosistema , Peces , Humanos , Dibenzodioxinas Policloradas/análisis , Contaminantes Químicos del Agua/análisis
3.
Chemosphere ; 257: 127137, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32480086

RESUMEN

Polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs) and polychlorinated biphenyls (PCBs) are persistent organic pollutants that have detrimental health effects. As people are exposed to them mainly through the diet, EU has set maximum food dioxin and PCBs levels. EFSA CONTAM Panel made new risk assessment in 2018 that lowered the tolerable weekly intake (TWI) from 14 pg-TEQ/kg bw/week to 2 pg-TEQ/kg bw/week. Critical effect was decreased semen count at the age of 18-19 years if serum total TEQ at the age of 9 years exceeded the No Observed Adverse Effect Level (NOAEL) of 7 pg/g lipid. However, it is largely unknown to what extent NOAEL is exceed in European boys currently. We thus measured PCBs from small volume of serum in 184 Finnish children 7-10 years of age. To estimate the TEQ levels of children from measured PCB levels, we used our existing human milk PCDD/F and PCB concentrations to create a hierarchical Bayesian regression model that was used to estimate TEQs from measured PCBs. For quality control (QC), three pooled blood samples from 18 to 20 year old males were measured for PCDD/Fs and PCBs, and estimated for TEQs. In QC samples measured and estimated TEQs agreed within 84%-106%. In our estimate for 7-10 year old children, PCDD/F TEQ exceeded NOAEL only in 0.5% and total TEQ in 2.7% of subjects. Risk management following the decreased TWI proposed by the CONTAM Panel should be carefully considered if total TEQ in children is already largely below the NOAEL.


Asunto(s)
Dibenzofuranos Policlorados/sangre , Exposición a Riesgos Ambientales/análisis , Contaminantes Ambientales/sangre , Dibenzodioxinas Policloradas/sangre , Adolescente , Adulto , Teorema de Bayes , Benzofuranos/análisis , Niño , Dibenzofuranos , Dibenzofuranos Policlorados/análisis , Dieta , Dioxinas/análisis , Exposición a Riesgos Ambientales/estadística & datos numéricos , Contaminantes Ambientales/análisis , Finlandia , Contaminación de Alimentos/análisis , Humanos , Leche Humana/química , Bifenilos Policlorados/análisis , Dibenzodioxinas Policloradas/análisis , Medición de Riesgo , Adulto Joven
4.
Health Res Policy Syst ; 18(1): 36, 2020 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-32245481

RESUMEN

BACKGROUND: Evidence-informed decision-making and better use of scientific information in societal decisions has been an area of development for decades but is still topical. Decision support work can be viewed from the perspective of information collection, synthesis and flow between decision-makers, experts and stakeholders. Open policy practice is a coherent set of methods for such work. It has been developed and utilised mostly in Finnish and European contexts. METHODS: An overview of open policy practice is given, and theoretical and practical properties are evaluated based on properties of good policy support. The evaluation is based on information from several assessments and research projects developing and applying open policy practice and the authors' practical experiences. The methods are evaluated against their capability of producing quality of content, applicability and efficiency in policy support as well as how well they support close interaction among participants and understanding of each other's views. RESULTS: The evaluation revealed that methods and online tools work as expected, as demonstrated by the assessments and policy support processes conducted. The approach improves the availability of information and especially of relevant details. Experts are ambivalent about the acceptability of openness - it is an important scientific principle, but it goes against many current research and decision-making practices. However, co-creation and openness are megatrends that are changing science, decision-making and the society at large. Against many experts' fears, open participation has not caused problems in performing high-quality assessments. On the contrary, a key challenge is to motivate and help more experts, decision-makers and citizens to participate and share their views. Many methods within open policy practice have also been widely used in other contexts. CONCLUSIONS: Open policy practice proved to be a useful and coherent set of methods. It guided policy processes toward a more collaborative approach, whose purpose was wider understanding rather than winning a debate. There is potential for merging open policy practice with other open science and open decision process tools. Active facilitation, community building and improving the user-friendliness of the tools were identified as key solutions for improving the usability of the method in the future.


Asunto(s)
Toma de Decisiones , Formulación de Políticas , Política de Salud , Humanos , Proyectos de Investigación , Red Social
5.
BMC Public Health ; 20(1): 389, 2020 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-32213168

RESUMEN

It was highlighted that the original article [1] contained a formatting error in the equations.

6.
BMC Public Health ; 20(1): 64, 2020 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-31941472

RESUMEN

BACKGROUND: Health risks linked with dioxin in fish remain a complex policy issue. Fatty Baltic fish contain persistent pollutants, but they are otherwise healthy food. We studied the health benefits and risks associated with Baltic herring and salmon in four countries to identify critical uncertainties and to facilitate an evidence-based discussion. METHODS: We performed an online survey investigating consumers' fish consumption and its motivation in Denmark, Estonia, Finland, and Sweden. Dioxin and methylmercury concentrations were estimated based on Finnish studies. Exposure-response functions for several health endpoints were evaluated and quantified based on the scientific literature. We also quantified the infertility risk of men based on a recent European risk assessment estimating childhood dioxin exposure and its effect on sperm concentration later in life. RESULTS: Baltic herring and salmon contain omega-3 fatty acids and vitamin D, and the beneficial impact of these fishes on cardiovascular diseases, mortality, and the risk of depression and cancer clearly outweighs risks of dioxins and methylmercury in people older than 45 years of age and in young men. Young women may expose their children to pollutants during pregnancy and breast feeding. This study suggests that even in this critical subgroup, the risks are small and the health benefits are greater than or at least similar to the health risks. Value of information analysis demonstrated that the remaining scientific uncertainties are not large. In contrast, there are several critical uncertainties that are inherently value judgements, such as whether exceeding the tolerable weekly intake is an adverse outcome as such; and whether or not subgroup-specific restrictions are problematic. CONCLUSIONS: The potential health risks attributable to dioxins in Baltic fish have more than halved in the past 10 years. The new risk assessment issued by the European Food Safety Authority clearly increases the fraction of the population exceeding the tolerable dioxin intake, but nonetheless, quantitative estimates of net health impacts change only marginally. Increased use of small herring (which have less pollutants) is a no-regret option. A more relevant value-based policy discussion rather than research is needed to clarify official recommendations related to dioxins in fish.


Asunto(s)
Contaminantes Ambientales/efectos adversos , Contaminantes Ambientales/análisis , Peces , Contaminación de Alimentos/análisis , Alimentos Marinos/análisis , Adulto , Animales , Niño , Dioxinas/efectos adversos , Dioxinas/análisis , Estudios de Evaluación como Asunto , Femenino , Humanos , Recién Nacido , Infertilidad Masculina/inducido químicamente , Masculino , Compuestos de Metilmercurio/efectos adversos , Compuestos de Metilmercurio/análisis , Valor Nutritivo , Embarazo , Medición de Riesgo , Salmón , Países Escandinavos y Nórdicos , Enfermedades Dentales/inducido químicamente
7.
Risk Anal ; 40(4): 674-695, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31820829

RESUMEN

Mortality effects of exposure to air pollution and other environmental hazards are often described by the estimated number of "premature" or "attributable" deaths and the economic value of a reduction in exposure as the product of an estimate of "statistical lives saved" and a "value per statistical life." These terms can be misleading because the number of deaths advanced by exposure cannot be determined from mortality data alone, whether from epidemiology or randomized trials (it is not statistically identified). The fraction of deaths "attributed" to exposure is conventionally derived as the hazard fraction (R - 1)/R, where R is the relative risk of mortality between high and low exposure levels. The fraction of deaths advanced by exposure (the "etiologic" fraction) can be substantially larger or smaller: it can be as large as one and as small as 1/e (≈0.37) times the hazard fraction (if the association is causal and zero otherwise). Recent literature reveals misunderstanding about these concepts. Total life years lost in a population due to exposure can be estimated but cannot be disaggregated by age or cause of death. Economic valuation of a change in exposure-related mortality risk to a population is not affected by inability to know the fraction of deaths that are etiologic. When individuals facing larger or smaller changes in mortality risk cannot be identified, the mean change in population hazard is sufficient for valuation; otherwise, the economic value can depend on the distribution of risk reductions.


Asunto(s)
Contaminación del Aire/efectos adversos , Exposición a Riesgos Ambientales , Esperanza de Vida , Modelos Estadísticos , Mortalidad Prematura , Femenino , Humanos , Masculino
8.
Prev Med Rep ; 14: 100842, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31193440

RESUMEN

[This corrects the article DOI: 10.1016/j.pmedr.2017.03.019.].

9.
Ecol Evol ; 8(6): 3518-3533, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29607043

RESUMEN

Various hypotheses have been proposed for why the traits distinguishing humans from other primates originally evolved, and any given trait may have been explained both as an adaptation to different environments and as a result of demands from social organization or sexual selection. To find out how popular the different explanations are among scientists, we carried out an online survey among authors of recent scientific papers in journals covering relevant fields of science (paleoanthropology, paleontology, ecology, evolution, human biology). Some of the hypotheses were clearly more popular among the 1,266 respondents than others, but none was universally accepted or rejected. Even the most popular of the hypotheses were assessed "very likely" by <50% of the respondents, but many traits had 1-3 hypotheses that were found at least moderately likely by >70% of the respondents. An ordination of the hypotheses identified two strong gradients. Along one gradient, the hypotheses were sorted by their popularity, measured by the average credibility score given by the respondents. The second gradient separated all hypotheses postulating adaptation to swimming or diving into their own group. The average credibility scores given for different subgroups of the hypotheses were not related to respondent's age or number of publications authored. However, (paleo)anthropologists were more critical of all hypotheses, and much more critical of the water-related ones, than were respondents representing other fields of expertise. Although most respondents did not find the water-related hypotheses likely, only a small minority found them unscientific. The most popular hypotheses were based on inherent drivers; that is, they assumed the evolution of a trait to have been triggered by the prior emergence of another human-specific behavioral or morphological trait, but opinions differed as to which of the traits came first.

10.
Prev Med Rep ; 6: 265-270, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28409088

RESUMEN

Climate change mitigation policies aim to reduce climate change through reducing greenhouse gas (GHG) emissions whereas adaption policies seek to enable humans to live in a world with increasingly variable and more extreme climatic conditions. It is increasingly realised that enacting such policies will have unintended implications for public health, but there has been less focus on their implications for wellbeing. Wellbeing can be defined as a positive mental state which is influenced by living conditions. As part of URGENCHE, an EU funded project to identify health and wellbeing outcomes of city greenhouse gas emission reduction policies, a survey designed to measure these living conditions and levels of wellbeing in Kuopio, Finland was collected in December 2013. Kuopio was the northmost among seven cities in Europe and China studied. Generalised estimating equation modelling was used to determine which living conditions were associated with subjective wellbeing (measured through the WHO-5 Scale). Local greenspace and spending time in nature were associated with higher levels of wellbeing whereas cold housing and poor quality indoor air were associated with lower levels of wellbeing. Thus adaption policies to increase greenspace might, in addition to reducing heat island effects, have the co-benefit of increasing wellbeing and improving housing insulation.

11.
Toxicol Lett ; 270: 8-11, 2017 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-28189645

RESUMEN

Soft-tissue sarcoma is one of the few specific tumors thought to be caused by polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and specifically TCDD. Evidence is, however, based on questionnaire-based case-control studies, and on very few cancer cases in cohort studies at high occupational exposures to chlorophenols or chlorophenoxy acid herbicides with dioxin impurities. Recall bias has been suspected to influence the reporting of exposure, but this possibility has never been adequately put to test. In the present study 87 cancer patients and 308 controls answered a questionnaire asking their exposure to wood preservatives, fungicides and herbicides, and insecticides, and their PCDD/F concentrations were also measured. After matching for age and area 67-69 sarcoma patients and 153-156 controls were available for the study depending on the chemical group, 1-3 controls for each sarcoma patient. Sarcoma patients reported exposure to these chemicals significantly more often than controls did, odds ratios were 6.7 for wood preservatives (p=0.02), 16 for fungicides and herbicides (p=0.01), and 4.9 for insecticides (p=0.06). There was no association, when the analysis was based on measured PCDD/F concentrations (odds ratios close to 1). Although it is not possible to exclude the role of the main chemical as the cause with certainty, the results indicate that recall bias is very likely in previous studies. Thus the causality between contaminant PCDD/Fs and soft tissue sarcoma cannot be considered proven.


Asunto(s)
Dioxinas/toxicidad , Exposición a Riesgos Ambientales/efectos adversos , Sarcoma/inducido químicamente , Encuestas y Cuestionarios , Estudios de Casos y Controles , Clorofenoles/toxicidad , Estudios de Cohortes , Dioxinas/administración & dosificación , Herbicidas/toxicidad , Humanos , Insecticidas/toxicidad , Exposición Profesional/efectos adversos , Sarcoma/diagnóstico
12.
Toxicol Lett ; 261: 41-48, 2016 Nov 02.
Artículo en Inglés | MEDLINE | ID: mdl-27575567

RESUMEN

A number of studies have found an association between the concentrations of persistent organic pollutants (POP) and type 2 diabetes. Causality has remained uncertain. This study describes the pharmacokinetic behavior of PCDD/Fs (polychlorinated dibenzo-p-dioxins and dibenzofurans) both in a theoretical model based on elimination rate constants, and in a group of 409 adult surgical patients with known PCDD/F concentrations and dietary information. A model assuming 10% annual decrease in past PCDD/F intake, predicted the measured profile of TEQ (toxic equivalents) in the patient population fairly well. The dominant determinant of PCDD/F level was age, and the level in patients was also associated with consumption of animal source products. Predicted daily intakes correlated with diet, but also with body mass index (BMI), indicating that high BMI was preceded by high consumption of foods containing PCDD/Fs. The results suggest that a third factor, e.g. high intake of animal source foods, could explain both higher levels of POPs in the body and higher incidence of type 2 diabetes, and BMI is not sufficient in describing the confounding caused by diet. Thus, to fully address the causality between POPs and type 2 diabetes, careful studies considering the pharmacokinetics of the studied compounds, and including the analysis of food consumption, are needed.


Asunto(s)
Diabetes Mellitus Tipo 2/inducido químicamente , Dibenzofuranos/farmacocinética , Contaminantes Ambientales/farmacocinética , Contaminantes Ambientales/toxicidad , Contaminación de Alimentos , Dibenzodioxinas Policloradas/toxicidad , Índice de Masa Corporal , Registros de Dieta , Humanos , Dibenzodioxinas Policloradas/farmacocinética , Estudios Retrospectivos
13.
Environ Health ; 15 Suppl 1: 25, 2016 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-26960925

RESUMEN

BACKGROUND: Climate change is a global threat to health and wellbeing. Here we provide findings of an international research project investigating the health and wellbeing impacts of policies to reduce greenhouse gas emissions in urban environments. METHODS: Five European and two Chinese city authorities and partner academic organisations formed the project consortium. The methodology involved modelling the impact of adopted urban climate-change mitigation transport, buildings and energy policy scenarios, usually for the year 2020 and comparing them with business as usual (BAU) scenarios (where policies had not been adopted). Carbon dioxide emissions, health impacting exposures (air pollution, noise and physical activity), health (cardiovascular, respiratory, cancer and leukaemia) and wellbeing (including noise related wellbeing, overall wellbeing, economic wellbeing and inequalities) were modelled. The scenarios were developed from corresponding known levels in 2010 and pre-existing exposure response functions. Additionally there were literature reviews, three longitudinal observational studies and two cross sectional surveys. RESULTS: There are four key findings. Firstly introduction of electric cars may confer some small health benefits but it would be unwise for a city to invest in electric vehicles unless their power generation fuel mix generates fewer emissions than petrol and diesel. Second, adopting policies to reduce private car use may have benefits for carbon dioxide reduction and positive health impacts through reduced noise and increased physical activity. Third, the benefits of carbon dioxide reduction from increasing housing efficiency are likely to be minor and co-benefits for health and wellbeing are dependent on good air exchange. Fourthly, although heating dwellings by in-home biomass burning may reduce carbon dioxide emissions, consequences for health and wellbeing were negative with the technology in use in the cities studied. CONCLUSIONS: The climate-change reduction policies reduced CO2 emissions (the most common greenhouse gas) from cities but impact on global emissions of CO2 would be more limited due to some displacement of emissions. The health and wellbeing impacts varied and were often limited reflecting existing relatively high quality of life and environmental standards in most of the participating cities; the greatest potential for future health benefit occurs in less developed or developing countries.


Asunto(s)
Contaminación del Aire/prevención & control , Efecto Invernadero/prevención & control , Política de Salud/legislación & jurisprudencia , Salud Pública/legislación & jurisprudencia , Contaminantes Atmosféricos/análisis , China , Ciudades , Cambio Climático , Estudios Transversales , Europa (Continente) , Unión Europea , Gases/análisis , Regulación Gubernamental , Humanos , Estudios Longitudinales
14.
Environ Res ; 146: 350-8, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26803213

RESUMEN

BACKGROUND: Green house gas (GHG) mitigation policies can be evaluated by showing their co-benefits to health. METHOD: Health Impact Assessment (HIA) was used to quantify co-benefits of GHG mitigation policies in Rotterdam. The effects of two separate interventions (10% reduction of private vehicle kilometers and a share of 50% electric-powered private vehicle kilometers) on particulate matter (PM2.5), elemental carbon (EC) and noise (engine noise and tyre noise) were assessed using Years of Life Lost (YLL) and Years Lived with Disability (YLD). The baseline was 2010 and the end of the assessment 2020. RESULTS: The intervention aimed at reducing traffic is associated with a decreased exposure to noise resulting in a reduction of 21 (confidence interval (CI): 11-129) YLDs due to annoyance and 35 (CI: 20-51) YLDs due to sleep disturbance for the population per year. The effects of 50% electric-powered car use are slightly higher with a reduction of 26 (CI: 13-116) and 41 (CI: 24-60) YLDs, respectively. The two interventions have marginal effects on air pollution, because already implemented traffic policies will reduce PM2.5 and EC by around 40% and 60% respectively, from 2010 to 2020. DISCUSSION: The evaluation of planned interventions, related to climate change policies, targeting only the transport sector can result in small co-benefits for health, if the analysis is limited to air pollution and noise. This urges to expand the analysis by including other impacts, e.g. physical activity and well-being, as a necessary step to better understanding consequences of interventions and carefully orienting resources useful to build knowledge to improve public health.


Asunto(s)
Política Ambiental , Efecto Invernadero/legislación & jurisprudencia , Evaluación del Impacto en la Salud/métodos , Vehículos a Motor , Transportes/legislación & jurisprudencia , Contaminación del Aire/prevención & control , Ciudades , Efecto Invernadero/prevención & control , Humanos , Vehículos a Motor/clasificación , Vehículos a Motor/estadística & datos numéricos , Países Bajos , Ruido/legislación & jurisprudencia , Ruido/prevención & control , Emisiones de Vehículos/legislación & jurisprudencia , Emisiones de Vehículos/prevención & control
15.
Environ Health ; 14: 93, 2015 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-26667475

RESUMEN

BACKGROUND: Public health is often affected by societal decisions that are not primarily about health. Climate change mitigation requires intensive actions to minimise greenhouse gas emissions in the future. Many of these actions take place in cities due to their traffic, buildings, and energy consumption. Active climate mitigation policies will also, aside of their long term global impacts, have short term local impacts, both positive and negative, on public health. Our main objective was to develop a generic open impact model to estimate health impacts of emissions due to heat and power consumption of buildings. In addition, the model should be usable for policy comparisons by non-health experts on city level with city-specific data, it should give guidance on the particular climate mitigation questions but at the same time increase understanding on the related health impacts and the model should follow the building stock in time, make comparisons between scenarios, propagate uncertainties, and scale to different levels of detail. We tested The functionalities of the model in two case cities, namely Kuopio and Basel. We estimated the health and climate impacts of two actual policies planned or implemented in the cities. The assessed policies were replacement of peat with wood chips in co-generation of district heat and power, and improved energy efficiency of buildings achieved by renovations. RESULTS: Health impacts were not large in the two cities, but also clear differences in implementation and predictability between the two tested policies were seen. Renovation policies can improve the energy efficiency of buildings and reduce greenhouse gas emissions significantly, but this requires systematic policy sustained for decades. In contrast, fuel changes in large district heating facilities may have rapid and large impacts on emissions. However, the life cycle impacts of different fuels is somewhat an open question. CONCLUSIONS: In conclusion, we were able to develop a practical model for city-level assessments promoting evidence-based policy in general and health aspects in particular. Although all data and code is freely available, implementation of the current model version in a new city requires some modelling skills.


Asunto(s)
Cambio Climático , Fuentes Generadoras de Energía , Política Ambiental , Arquitectura y Construcción de Instituciones de Salud , Evaluación del Impacto en la Salud , Calefacción , Salud Urbana , China , Europa (Continente) , Humanos , Modelos Teóricos
16.
Duodecim ; 131(22): 2179-87, 2015.
Artículo en Finés | MEDLINE | ID: mdl-26749911

RESUMEN

Big data (very large data sets) are increasing in an accelerating speed. More and more data is also becoming freely available. This article is an overview of this progress and data sources related to molecular biology and public health especially from the Finnish perspective. Finland has several excellent data sources that are currently not used effectively. Big data has already produced major benefits especially in molecular biology, but benefits in public health and individual choice are only now being materialised. The paradigm in research may change dramatically, if the effort switches from article production to the production of knowledge crystals, i.e. collaborative data-based answers to research questions. Also the role of a clinician is becoming more like that of a coach.


Asunto(s)
Conjuntos de Datos como Asunto , Promoción de la Salud , Biología Molecular , Salud Pública , Finlandia , Humanos
17.
Basic Clin Pharmacol Toxicol ; 114(6): 497-509, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24418412

RESUMEN

In haem degradation, haem oxygenase-1 (HO-1) first cleaves haem to biliverdin, which is reduced to bilirubin by biliverdin IXα reductase (BVR-A). The environmental pollutant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) causes hepatic accumulation of biliverdin in moderately TCDD-resistant line B (Kuopio) rats. Using line B and two TCDD-sensitive rat strains, the present study set out to probe the dose-response and biochemical mechanisms of this accumulation. At 28 days after exposure to 3-300 µg/kg TCDD in line B rats, already the lowest dose of TCDD tested, 3 µg/kg, affected serum bilirubin conjugates, and after doses ≥100 µg/kg, the liver content of bilirubin, biliverdin and their conjugates (collectively 'bile pigments') as well as HO-1 was elevated. BVR-A activity and serum bile acids were increased only by the doses of 100 and 300 µg/kg TCDD, respectively. Biliverdin conjugates correlated best with biliverdin suggesting it to be their immediate precursor. TCDD (100 µg/kg, 10 days) increased hepatic bilirubin and biliverdin levels also in TCDD-sensitive Long-Evans (Turku/AB; L-E) rats. Hepatic bilirubin and bile acids, but not biliverdin, were increased in feed-restricted L-E control rats. In TCDD-sensitive line C (Kuopio) rats, 10 µg/kg of TCDD increased the body-weight-normalized biliary excretion of bilirubin. Altogether, the results suggest that at acutely toxic doses, TCDD induces the formation of bilirubin in rats. However, concurrently, TCDD seems to hamper the quantitative conversion of biliverdin to bilirubin in line B and L-E rats' liver. Biliverdin conjugates are most likely formed as secondary products of biliverdin.


Asunto(s)
Bilirrubina/biosíntesis , Biliverdina/metabolismo , Hígado/metabolismo , Dibenzodioxinas Policloradas/toxicidad , Receptores de Hidrocarburo de Aril/fisiología , Animales , Ácidos y Sales Biliares/metabolismo , Bilirrubina/sangre , Cromatografía Líquida de Alta Presión , Femenino , Ratas
18.
Int J Environ Res Public Health ; 10(7): 2621-42, 2013 Jun 26.
Artículo en Inglés | MEDLINE | ID: mdl-23803642

RESUMEN

The calls for knowledge-based policy and policy-relevant research invoke a need to evaluate and manage environment and health assessments and models according to their societal outcomes. This review explores how well the existing approaches to assessment and model performance serve this need. The perspectives to assessment and model performance in the scientific literature can be called: (1) quality assurance/control, (2) uncertainty analysis, (3) technical assessment of models, (4) effectiveness and (5) other perspectives, according to what is primarily seen to constitute the goodness of assessments and models. The categorization is not strict and methods, tools and frameworks in different perspectives may overlap. However, altogether it seems that most approaches to assessment and model performance are relatively narrow in their scope. The focus in most approaches is on the outputs and making of assessments and models. Practical application of the outputs and the consequential outcomes are often left unaddressed. It appears that more comprehensive approaches that combine the essential characteristics of different perspectives are needed. This necessitates a better account of the mechanisms of collective knowledge creation and the relations between knowledge and practical action. Some new approaches to assessment, modeling and their evaluation and management span the chain from knowledge creation to societal outcomes, but the complexity of evaluating societal outcomes remains a challenge.


Asunto(s)
Ambiente , Modelos Teóricos , Toma de Decisiones , Estado de Salud , Humanos
19.
Food Chem Toxicol ; 54: 70-7, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22425939

RESUMEN

Methylmercury (MeHg) is a well-known neurotoxic agent, and consumption of contaminated fish is the principal environmental source of MeHg exposure in humans. Children are more susceptible to adverse effects than adults. No previous specific data exist for intake by Finnish children of methylmercury from fish. We estimated fish consumption and MeHg intakes from species most commonly consumed by Finnish children aged 1-6 years. The total mercury concentrations were determined in fish species consumed, and age-specific methylmercury intakes were derived. We also examined safety margins and the proportion of children exceeding the tolerable daily intakes set by international expert bodies. The daily intake of MeHg ranged from 0 to 0.33 µg/kg bw. The strictest reference value 0.1 µg/kg bw/day for MeHg, proposed by USEPA, was exceeded by 1-15% of the study population, and FAO/WHO JECFA provisional tolerable weekly intake of 1.6 µg/kg bw was exceeded by 1% of boys and 2.5% of girls aged 6 years. Intakes of 1-year old girls were higher than of boys, whereas for 3-year olds they were the opposite. The highest intakes were observed for 6-year-old boys and girls. There was great variation in the estimated MeHg intakes among Finnish children.


Asunto(s)
Peces , Compuestos de Metilmercurio/toxicidad , Alimentos Marinos , Animales , Niño , Preescolar , Femenino , Finlandia , Humanos , Lactante , Masculino , Compuestos de Metilmercurio/administración & dosificación
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