884 resultados para Risk exposure
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Currently, there is increasing use of nanomaterials in the food industry thanks to the many advantages offered and make the products that contain them more competitive in the market. Their physicochemical properties often differ from those of bulk materials, which require specialized risk assessment. This should cover the risks to the health of workers and consumers as well as possible environmental risks. The risk assessment methods must go updating due to more widespread use of nanomaterials, especially now that are making their way down to consumer products. Today there is no specific legislation for nanomaterials, but there are several european dispositions and regulations that include them. This review gives an overview of the risk assessment and the existing current legislation regarding the use of nanotechnology in the food industry.
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It is apparent that most of the techniques that make use of ionising radiation in human medical practices are now being applied in veterinary medicine. Steps are being taken by the IAEA to provide guidance for humans involved in such practices, but there appears to be no international initiative that considers the protection or welfare of the animal as a patient. There is therefore a risk that the deliberate exposure of an animal, particularly in the therapeutic application of radiation, could do more harm than good. In the light of recent developments in dosimetric modelling and the application of known effects of radiation on different types of animals, for the purposes of the protection of biota in an environmental context, it is argued that it would be sensible now to start a serious consideration of this issue. Some suggestions are made with regard to a number of areas that could be considered further, both specifically and with regard to the field of radiological protection as a whole.
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It is apparent that most of the techniques that make use of ionising radiation in human medical practices are now being applied in veterinary medicine. Steps are being taken by the IAEA to provide guidance for humans involved in such practices, but there appears to be no international initiative that considers the protection or welfare of the animal as a patient. There is therefore a risk that the deliberate exposure of an animal, particularly in the therapeutic application of radiation, could do more harm than good. In the light of recent developments in dosimetric modelling and the application of known effects of radiation on different types of animals, for the purposes of the protection of biota in an environmental context, it is argued that it would be sensible now to start a serious consideration of this issue. Some suggestions are made with regard to a number of areas that could be considered further, both specifically and with regard to the field of radiological protection as a whole.
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Background & Aims: Certain subsets of colorectal serrated polyps (SP) have malignant potential. Weperformed a systematic review and meta-analysis to investigate the association between modifiablelifestyle factors and risk for SPs.
Methods: We conducted a systematic search of Medline, Embase, and Web of Science, forobservational or interventional studies that contained the terms risk or risk factor, and serrated orhyperplastic, and polyps or adenomas, and colorectal (or synonymous terms), published by March2016. Titles and abstracts of identified articles were independently reviewed by at least 2 reviewers.Adjusted relative risks (RR) and 95% CIs were combined using random effects meta-analyses toassess the risk of SP, when possible.
Results: We identified 43 studies of SP risk associated with 7 different lifestyle factors: smoking,alcohol, body fatness, diet, physical activity, medication and/or hormone replacement therapy.When we compared the highest and lowest categories of exposure, factors we found to significantlyincrease risk for SP included tobacco smoking (RR, 2.47; 95% CI, 2.12–2.87), alcohol intake (RR, 1.33;95% CI, 1.17–1.52), body mass index (RR, 1.40; 95% CI, 1.22–1.61), and high intake of fat or meat.Direct associations for smoking and alcohol, but not body fat, tended to be stronger for sessileserrated adenomas/polyps than hyperplastic polyps. In contrast, factors we found to significantlydecrease risks for SP included use of non-steroidal anti-inflammatory drugs (RR, 0.77; 95% CI, 0.65–0.92) or aspirin (RR, 0.81; 95% CI, 0.67–0.99), as well as high intake of folate, calcium, or fiber. Nosignificant associations were detected between SP risk and physical activity or hormone replacementtherapy.
Conclusions: Several lifestyle factors, most notably smoking and alcohol, are associated with SP risk.These findings enhance our understanding of mechanisms of SP development and indicate that riskof serrated pathway colorectal neoplasms could be reduced with lifestyle changes.
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Evidence of an association between early pregnancy exposure to selective serotonin reuptake inhibitors (SSRI) and congenital heart defects (CHD) has contributed to recommendations to weigh benefits and risks carefully. The objective of this study was to determine the specificity of association between first trimester exposure to SSRIs and specific CHD and other congenital anomalies (CA) associated with SSRI exposure in the literature (signals). A population-based case-malformed control study was conducted in 12 EUROCAT CA registries covering 2.1 million births 1995-2009 including livebirths, fetal deaths from 20 weeks gestation and terminations of pregnancy for fetal anomaly. Babies/fetuses with specific CHD (n = 12,876) and non-CHD signal CA (n = 13,024), were compared with malformed controls whose diagnosed CA have not been associated with SSRI in the literature (n = 17,083). SSRI exposure in first trimester pregnancy was associated with CHD overall (OR adjusted for registry 1.41, 95% CI 1.07-1.86, fluoxetine adjOR 1.43 95% CI 0.85-2.40, paroxetine adjOR 1.53, 95% CI 0.91-2.58) and with severe CHD (adjOR 1.56, 95% CI 1.02-2.39), particularly Tetralogy of Fallot (adjOR 3.16, 95% CI 1.52-6.58) and Ebstein's anomaly (adjOR 8.23, 95% CI 2.92-23.16). Significant associations with SSRI exposure were also found for ano-rectal atresia/stenosis (adjOR 2.46, 95% CI 1.06-5.68), gastroschisis (adjOR 2.42, 95% CI 1.10-5.29), renal dysplasia (adjOR 3.01, 95% CI 1.61-5.61), and clubfoot (adjOR 2.41, 95% CI 1.59-3.65). These data support a teratogenic effect of SSRIs specific to certain anomalies, but cannot exclude confounding by indication or associated factors.
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To get a better insight into the radiological features of industrial by-products that can be reused in building materials a review of the reported scientific data can be very useful. The current study is based on the continuously growing database of the By-BM (H2020-MSCA-IF-2015) project (By-products for Building Materials). Currently, the By-BM database contains individual data of about 431 by-products and 1095 building and raw materials. It was found that in case of the building materials the natural radionuclide content varied widely (Ra-226: <DL-27851 Bq/kg; Th-232: <DL-906 Bq/kg, K-40: <DL-17922 Bq/kg), more so than for the by-products (Ra-226: 7-3152 Bq/kg; Th-232: <DL-1350 Bq/kg, K-40: <DL-3001 Bq/kg). The average Ra-226, Th-232 and K-40 contents of the reported by-products were respectively 2.52, 2.35 and 0.39 times higher than the building materials. The gamma exposure of bulk building products was calculated according to IAEA Specific Safety Guide No. SSG-32 and the European Commission Radiation Protection 112 based I-index (EU BSS). It was found that in most cases the I-index without density consideration provides a significant overestimation in excess effective dose.
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[EN]All the relevant risk factors contributing to breast cancer etiology are not fully known. Exposure to organochlorine pesticides has been linked to an increased incidence of the disease, although not all data have been consistent. Most published studies evaluated the exposure to organochlorines individually, ignoring the potential effects exerted by the mixtures of chemicals.
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Contrary to intuition, use of lower strength nicotine e-liquids might not offer reduced health risk if compensatory puffing behaviour occurs. Compensatory puffing (e.g. more frequent, longer puffs) or user behaviour (increasing the wattage) can lead to higher temperatures at which glycerine and propylene glycol (solvents used in e-liquids) undergo decomposition to carbonyl compounds, including the carcinogens formaldehyde and acetaldehyde. This study aims to document puffing patterns and user behaviour associated with using high and low strength nicotine e-liquid and associated toxicant/carcinogen exposure in experienced e-cigarette users (known as vapers herein).
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An increasingly older population will most likely lead to greater demands on the health care system, as older age is associated with an increased risk of having acute and chronic conditions. The number of diseases or disabilities is not the only marker of the amount of health care utilized, as persons may seek hospitalization without a disease and/or illness that requires hospital healthcare. Hospitalization may pose a severe risk to older persons, as exposure to the hospital environment may lead to increased risks of iatrogenic disorders, confusion, falls and nosocomial infections, i.e., disorders that may involve unnecessary suffering and lead to serious consequences. Aims: The overall aim of this thesis was to describe and explore individual trajectories of cognitive development in relation to hospitalization and risk factors for hospitalization among older persons living in different accommodations in Sweden and to explore older persons' reasons for being transferred to a hospital. Methods: The study designs were longitudinal, prospective and descriptive, and both quantitative and qualitative methods were used. Specifically, latent growth curve modelling was used to assess the association of cognitive development with hospitalization. The Cox proportional hazards regression model was used to analyse factors associated with hospitalization risk overtime. In addition, an explorative descriptive design was used to explore how home health care patients experienced and perceived their decision to seek hospital care. Results: The most common reasons for hospitalization were cardiovascular diseases, which caused more than one-quarter of first hospitalizations among the persons living in ordinary housing and nursing home residents (NHRs). The persons who had been hospitalized had a lower mean level of cognitive performance in general cognition, verbal, spatial/fluid, memory and processing speed abilities compared to those who had not been hospitalized. Significantly steeper declines in general cognition, spatial/fluid and processing speed abilities were observed among the persons who had been hospitalized. Cox proportional hazards regression analysis showed that the number of diseases, number of drugs used, having experienced a fall and being assessed as malnourished according to the Mini Nutritional Assessment scale were related to an increased hospitalization risk among the NHRs. Among the older persons living in ordinary housing, the risk factors for hospitalization were related to marital status, i.e., unmarried persons and widows/widowers had a decreased hospitalization risk. In addition, among social factors, receipt of support from relatives was related to an increased hospitalization risk, while receipt of support from friends was related to a decreased risk. The number of illnesses was not associated with the hospitalization risk for older persons in any age group or for those of either sex, when controlling for other variables. The older persons who received home health care described different reasons for their decisions to seek hospital care. The underlying theme of the home health care patients’ perceptions of their transfer to a hospital involved trust in hospitals. This trust was shared by the home health care patients, their relatives and the home health care staff, according to the patients. Conclusions: This thesis revealed that middle-aged and older persons who had been hospitalized exhibited a steeper decline in cognition. Specifically, spatial/fluid, processing speed, and general cognitive abilities were affected. The steeper decline in cognition among those who had been hospitalized remained even after controlling for comorbidities. The most common causes of hospitalization among the older persons living in ordinary housing and in nursing homes were cardiovascular diseases, tumours and falls. Not only health-related factors, such as the number of diseases, number of drugs used, and being assessed as malnourished, but also social factors and marital status were related to the hospitalization risk among the older persons living in ordinary housing and in nursing homes. Some risk factors associated with hospitalization differed not only between the men and women but also among the different age groups. The information provided in this thesis could be applied in care settings by professionals who interact with older persons before they decide to seek hospital care. To meet the needs of an older population, health care systems need to offer the proper health care at the most appropriate level, and they need to increase integration and coordination among health care delivered by different care services.
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Thesis (Master's)--University of Washington, 2016-08
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Sandpits used by children are frequently visited by wild life which constitutes a source of fungal pathogens and allergenic fungi. This study aimed to take an unannounced snapshot of the urban levels of fungal contaminants in sands, using for this purpose two public recreational parks, three elementary schools and two kindergartens. All samples were from Lisbon and neighboring municipalities and were tested for fungi of clinical interest. Potentially pathogenic fungi were isolated from all samples besides one. Fusarium dimerum (32.4%) was found to be the dominant species in one park and Chrysonilia spp. in the other (46.6%). Fourteen different species and genera were detected and no dermatophytes were found. Of a total of 14 species and genera, the fungi most isolated from the samples of the elementary schools were Penicillium spp. (74%), Cladophialophora spp. (38%) and Cladosporium spp. (90%). Five dominant species and genera were isolated from the kindergartens. Penicillium spp. was the only genus isolated in one, though with remarkably high counts (32500 colony forming units per gram). In the other kindergarten Penicillium spp. were also the most abundant species, occupying 69% of all the fungi found. All of the samples exceeded the Maximum Recommended Value (MRV) for beach sand defined by Brandão et al. 2011, which are currently the only quantitative guidelines available for the same matrix. The fungi found confirm the potential risk of exposure of children to keratinophilic fungi and demonstrates that regular cleaning or replacing of sand needs to be implemented in order to minimize contamination.
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Risk assessment considerations - The concept that “safe levels of exposure” for humans can be identified for individual chemicals is central to the risk assessment of compounds with known toxicological profiles. Selection of agents for combination chemotherapy regimens involves minimize overlapping of mechanisms of action, antitumor activity and toxicity profile. Although the toxicological profile and mechanism of action of each individual drug is well characterized, the toxicological interactions between drugs are likely, but poorly established at occupational exposure context. The synergistic nature of interactions may help in understanding the adverse health effects observed in healthcare workers, where exposure situations are characterized by complex mixtures of chemical agents, and the levels of individual exposing agents are often not sufficiently high to explain the health complaints. However, if a substance is a genotoxic carcinogen, this would be the “lead effect”; normally, no OEL based on a NOEL would be derived and the level would be set so low that it would be unlikely that other effects would be expected. Aim of the study - Recently research project developed in Portuguese Hospitals characterize the occupational exposure to antineoplastic agents and the health effects related. The project aimed to assess exposure of the different risk groups that handle antineoplastic agents in the hospital setting, namely during preparation and administration of these drugs. Here it is presented and discussed the results in a study developed in two hospitals from Lisbon.
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Workers from feed production often develop allergic respiratory symptoms and fungi are likely to be a significant contributing factor to these symptoms. This study intended to characterize fungal contamination in two feed production units, one for poultry and other for swine consumption. We aimed at identifying which unit presented the highest risk of occupational exposure to Aspergillus spp.
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