8 research outputs found
Scientific Opinion about the Guidance of the Chemical Regulation Directorate (UK) on how aged sorption studies for pesticides should be conducted, analysed and used in regulatory assessments
Abstract The EFSA Panel on Plant Protection Products and their Residues reviewed the guidance on how aged sorption studies for pesticides should be conducted, analysed and used in regulatory assessment. The inclusion of aged sorption is a higher tier in the groundwater leaching assessment. The Panel based its review on a test with three substances taken from a data set provided by the European Crop Protection Association. Particular points of attention were the quality of the data provided, the proposed fitting procedure of aged sorption experiments and the proposed method for combining results obtained from aged sorption studies and lowerâtier studies on degradation and adsorption. Aged sorption was a relevant process in all cases studied. The test revealed that the guidance could generally be well applied and resulted in robust and plausible results. The Panel considers the guidance suitable for use in the groundwater leaching assessment after the recommendations in this Scientific Opinion have been implemented, with the exception of the use of field data to derive aged sorption parameters. The Panel noted that the draft guidance could only be used by experienced users because there is no software tool that fully supports the work flow in the guidance document. It is therefore recommended that a userâfriendly software tool be developed. Aged sorption lowered the predicted concentration in groundwater. However, because aged sorption experiments may be conducted in different soils than lowerâtier degradation and adsorption experiments, it cannot be guaranteed that the higher tier predicts lower concentrations than the lower tier, while lower tiers should be more conservative than higher tiers. To mitigate this problem, the Panel recommends using all available higherâ and lowerâtier data in the leaching assessment. The Panel further recommends that aged sorption parameters for metabolites be derived only from metaboliteâdosed studies. The formation fraction can be derived from parentâdosed degradation studies, provided that the parent and metabolite are fitted with the bestâfit model, which is the double firstâorder in parallel model in the case of aged sorption
Influence of intercalation methods in properties of Clay and carbon nanotube and high density polyethylene nanocomposites
ForĂȘt urbaine, vĂ©gĂ©tation et dĂ©veloppement de lâasthme infantile
Contexte : Lâinfluence de la vĂ©gĂ©tation urbaine sur le dĂ©veloppement de lâasthme infantile est controversĂ©e. Il est avancĂ© que les arbres (canopĂ©e urbaine) rĂ©duisent la pollution atmosphĂ©rique, un facteur de risque de lâasthme mais Ă©galement, que certains peuvent Ă©mettre des pollens et des composĂ©s organiques volatils biogĂ©niques, tout-autant des facteurs de risque pour le dĂ©veloppement de lâasthme chez lâenfant. Cependant, les risques associĂ©s Ă la canopĂ©e urbaine ont Ă©tĂ© Ă©tudiĂ©s Ă lâaide de donnĂ©es rudimentaires souvent, sans considĂ©ration pour la saison.
Objectifs : 1) CaractĂ©riser lâassociation entre la vĂ©gĂ©tation urbaine et le dĂ©veloppement de lâasthme en distinguant la vĂ©gĂ©tation totale et de la canopĂ©e des feuillus et de conifĂšres, en fonction des saisons de production de pollens et de feuilles des arbres. 2) Ăvaluer lâinfluence de la canopĂ©e dâarbres sur lâassociation entre les particules fines (PM2.5) et le dĂ©veloppement de lâasthme infantile.
MĂ©thodes : Nous avons utilisĂ© les donnĂ©es dâune cohorte de naissance ouverte contenant tous les enfants nĂ©s sur lâĂźle de MontrĂ©al (Canada) entre 2000 et 2015 et suivis jusquâĂ leurs 12 ans, crĂ©Ă©e Ă partir de donnĂ©es mĂ©dico-administratives agrĂ©gĂ©es. Lâexposition Ă la vĂ©gĂ©tation totale a Ă©tĂ© estimĂ©e Ă lâaide dâune mesure satellitaire appelĂ©e lâindice de vĂ©gĂ©tation par diffĂ©rence normalisĂ©e (NDVI) et lâexposition Ă la canopĂ©e urbaine, a Ă©tĂ© estimĂ©e Ă lâaide de donnĂ©es de tĂ©lĂ©dĂ©tection laser aĂ©roportĂ© - LiDAR permettant dâestimer lâaire de la canopĂ©e des feuillus et des conifĂšres dans un rayon de 250 m autour de la rĂ©sidence des participants, tout au long du suivi. En dehors des saisons de pollens et de feuilles des arbres, les variables dâexpositions ont Ă©tĂ© fixĂ©es Ă zĂ©ro. Des modĂšles de risque proportionnels de Cox ont Ă©tĂ© dĂ©veloppĂ©s pour estimer le risque associĂ© au NDVI et aux canopĂ©es dâarbres lors de la saison de pollens et de feuilles des arbres. La non-linĂ©aritĂ© a Ă©tĂ© modĂ©lisĂ©e Ă lâaide de catĂ©gories et de splines cubiques pour les expositions. Nous avons ensuite Ă©valuĂ© lâeffet de la canopĂ©e urbaine sur lâassociation entre les particules fines (PM2.5) et le dĂ©veloppement de la maladie.
RĂ©sultats : Parmi les 352 946 enfants inclus dans la cohorte et suivis pour un total de 1,7 millions de personnes-annĂ©es, 30 816 nouveaux cas d'asthme ont Ă©tĂ© identifiĂ©s pour un taux moyen de nouveaux cas dâasthme Ă©tait de 17,79 nouveaux cas par 1 000 personnes-annĂ©es. Le NDVI moyen annuel sâĂ©levait Ă 0,365 (Ăcart-type (ET) : 0,106) dans un rayon de 250 m centrĂ© sur la rĂ©sidence des participants. En saison de pollens, le NDVI moyen se rĂ©duisait Ă 0,089 (ET : 0,106) et Ă 0,15 (ET : 0,185) en saison de feuilles. En moyenne, les enfants Ă©taient exposĂ©s Ă trois fois plus de canopĂ©es de feuillus (moyenne = 12,3 (ET : 17,0) Ă103 m2) que de conifĂšres en saison de feuilles (moyenne= 4,5 (ET : 4,3) Ă103 m2), et sept fois plus en saison de pollens. Nos analyses ont rĂ©vĂ©lĂ© des associations distinctes en fonction des saisons pour le NDVI et la canopĂ©e de feuillus. Trop peu de conifĂšres Ă©taient prĂ©sents pour tirer des conclusions quant Ă leur effet. Les analyses Ă lâaide des splines cubiques pour les expositions ont indiquĂ© la prĂ©sence de relations non-linĂ©aires. La catĂ©gorisation des expositions a indiquĂ© que des niveaux moyens de canopĂ©e de feuillus en saisons de feuilles avaient un effet protecteur lorsque comparĂ©s aux non-exposĂ©s (Rapport de Risque (RR): 0,694 ; Intervalle de confiance (IC95%) : 0,680 â 0,708). Ă lâinverse, pour les journĂ©es de pollens, la canopĂ©e de feuillus autour de la rĂ©sidence Ă©tait associĂ©e Ă lâaugmentation du risque (RR =1,082 (IC95% 1,056 â 1,108)). Pour les catĂ©gories de NDVI annuel (non subdivisĂ© par saisons), aucune association nâa Ă©tĂ© dĂ©tectĂ©e. Pour finir, la canopĂ©e dâarbres et le NDVI nâont influencĂ© que trĂšs faiblement lâassociation entre les PM2.5 rĂ©gionaux et le dĂ©veloppement de lâasthme infantile. Cependant, une lĂ©gĂšre interaction a Ă©tĂ© observĂ©e entre les feuillus en saison de feuilles et les PM2.5. Des niveaux Ă©levĂ©s de feuillus autour de la rĂ©sidence en pĂ©riode de feuilles diminueraient le risque dâasthme associĂ© Ă lâexposition aux PM2.5.
Discussions : Les rĂ©sultats suggĂšrent que lâeffet de la vĂ©gĂ©tation varie en fonction des saisons. Lâeffet captĂ© par le NDVI semble ĂȘtre en grande partie attribuable Ă la canopĂ©e de feuillus. Lâinfluence de la vĂ©gĂ©tation sur lâassociation entre les PM2.5 et le dĂ©veloppement de lâasthme est trĂšs faible.Background: The influence of urban vegetation and tree canopy on the development of childhood asthma is controversial. It is argued that trees reduce air pollution, a risk factor for asthma, but at the same time, some species emit pollens and biogenic volatile organic compounds, all of which are risk factors for the development of asthma in children. Yet, the risks associated with the urban canopy have been studied using rudimentary data, often without consideration for the season.
Objectives: 1) To characterize the association between urban vegetation and asthma development by distinguishing between total vegetation and deciduous and evergreen tree canopy, according to the pollen and leaf-on seasons. 2) To assess the influence of tree canopy on the association between fine particulate matter (PM2.5) and the development of childhood asthma.
Methods: We used data from an open birth cohort containing all children born on the island of Montreal, Canada, between 2000 and 2015 and followed up until their 13th birthday, created from aggregated medico-administrative data. Exposure to total vegetation was estimated using a satellite measure called the normalized difference vegetation index (NDVI). Exposure to the urban canopy was estimated using LiDAR, an airborne remote laser sensing technology that was used to estimate the area of the deciduous and coniferous canopy within a 250 m buffer centered on participants' residential postal codes, updated throughout the follow-up. Outside of the pollen and tree leaf-on seasons, exposure variables were set to zero. Cox proportional hazard models were developed to estimate the risk associated with NDVI and tree canopies for the pollen and tree leaf-on seasons. Nonlinearity was modeled using categories and restricted cubic splines for exposures variables. We then assessed the effect of the urban canopy on the association between fine particulate matter (PM2.5) and asthma development.
Results: Among the 352,946 children included in the cohort and followed for a total of 1.7 million person-years, 30,816 new asthma cases were detected, for an average incidence rate of 17.79 new cases per 1,000 person-years. The mean annual NDVI was 0.365 (Standard Deviation (SD): 0.106) within a 250 m buffer centered on participants' residential postal codes. In the pollen season, the mean NDVI was reduced to 0.089 (SD: 0.106) and to 0.15 (SD: 0.185) for the leaf-on season. On average, children were exposed to three times as much deciduous canopy (mean= 12.3 (SD: 17.0) Ă103 m2) as coniferous canopy in leaf-on season (mean= 4.5 (SD: 4.3) Ă103 m2), and seven times as much in pollen season. Our analyses revealed distinct associations by season for NDVI and deciduous trees. Too few evergreens were present to draw conclusions about their effect. Cubic spline analyses for exposures indicated the presence of nonlinear relationships. Exposure categorization indicated that average levels of deciduous trees canopy in the leaf-on season had a protective effect when compared to unexposed (Hazard Ratio (HR): 0.694; Confidence Interval (CI95%): 0.680 - 0.708). Conversely, for pollen days, the residential deciduous canopy was associated with increased risk (HR =1.082 (CI95% 1.056 - 1.108)). For annual NDVI categories (not subdivided by season), no association was detected. Finally, tree canopy and NDVI only weakly influenced the association between regional PM2.5 and childhood asthma development. However, a slight interaction was observed between leaf-on-season deciduous canopy and PM2.5. High levels of deciduous trees canopy at residential postal codes during the leaf-on season decrease the risk of asthma associated with PM2.5 exposure.
Discussion: Our results suggest that the effect of vegetation varies with season. The effect captured by NDVI appears to be largely due to the deciduous canopy. The influence of vegetation on the association between PM2.5 and asthma development appeared to be marginal
Extramedullary haemopoiesis and spinal cord compression.
Ethiopia's average life expectancy has improved by more than 18 years from 1990 to 2015. This initiated interest to study the gain in life expectancy with respect to age structure and cause of death. Applying a life expectancy decomposition technique on secondary data obtained from the Institute of Health Metrics and Evaluation, the study found that the burden of disease in Ethiopia has declined from 626.18 in 1990 to 225.69 in 2015 per 1000 population measured in age-standardized rate of life years lost. The major causes of burden in 1990; namely lower respiratory tract infections, neonatal disorders, diarrheal diseases and neglected tropical diseases at rates of 89.2, 63.2, 61.2, and 42.2 age-standardized years of life lost per 1000 population respectively; have shown a fast decline in 2015. Deaths from neglected tropical disease showed 94.95% reduction, contributing to 5.71(27.30%) years gain in life expectancy followed by lower respiratory tract infection and diarrheal disease contributing about 4.65 years (22.23%) and 1.48 years (7.10%) respectively. On the other hand, about 3.3 (15.73%) years and 6.4 (30.71%) years of increase in life expectancy are achieved through improved longevity in infants and children aged 1-4 years respectively. In conclusion, the study found that reductions in under-five child mortality and decline in burden of major communicable diseases could explain the major gain in life expectancy. However, findings also revealed that the prevalence of non-communicable diseases and injuries are on the rise calling for the need to be addressed by the public health system
Large-scale infectious disease testing programs have little consideration for equity: findings from a scoping review
International audienceObjective This scoping review aimed to identify how equity has been considered in large-scale infectious disease testing initiatives. Study Design and Setting Large-scale testing interventions are instrumental for infectious disease control and a central tool for the coronavirus 19 (COVID-19) pandemic. We searched Web of Science: core collection, Embase and Medline in June 2021 and followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses recommendations for scoping reviews. We critically analyzed the content of all included articles. Results Our search resulted in 2448 studies of which 86 were included for data extraction after screening. Of the included articles, 80% reported on COVID-19 -related screening programs. None of the studies presented a formal definition of (in)equity in testing, however, 71 articles did indirectly include elements of equity through the justification of their target population. Of these 71 studies, 58% articles indirectly alluded to health equity according to the PROGRESS-Plus framework, an acronym used to identify a list of socially stratifying characteristics driving inequity in health outcomes. Conclusion The studies included in our scoping review did not explicitly consider equity in their design or evaluation which is imperative for the success of infectious disease testing programs
Scientific statement on the coverage of bats by the current pesticide risk assessment for birds and mammals
Abstract Bats are an important group of mammals, frequently foraging in farmland and potentially exposed to pesticides. This statement considers whether the current risk assessment performed for birds and ground dwelling mammals exposed to pesticides is also protective of bats. Three main issues were addressed. Firstly, whether bats are toxicologically more or less sensitive than the most sensitive birds and mammals. Secondly, whether oral exposure of bats to pesticides is greater or lower than in ground dwelling mammals and birds. Thirdly, whether there are other important exposure routes relevant to bats. A large variation in toxicological sensitivity and no relationship between sensitivity of bats and bird or mammal testâspecies to pesticides could be found. In addition, bats have unique traits, such as echolocation and torpor which can be adversely affected by exposure to pesticides and which are not covered by the endpoints currently selected for wild mammal risk assessment. The current exposure assessment methodology was used for oral exposure and adapted to bats using batâspecific parameters. For oral exposure, it was concluded that for most standard risk assessment scenarios the current approach did not cover exposure of bats to pesticide residues in food. Calculations of potential dermal exposure for bats foraging during spraying operations suggest that this may be a very important exposure route. Dermal routes of exposure should be combined with inhalation and oral exposure. Based on the evidence compiled, the Panel concludes that bats are not adequately covered by the current risk assessment approach, and that there is a need to develop a batâspecific risk assessment scheme. In general, there was scarcity of data to assess the risks for bat exposed to pesticides. Recommendations for research are made, including identification of alternatives to laboratory testing of bats to assess toxicological effects
Scientific Opinion about the Guidance of the Chemical Regulation Directorate (UK) on how aged sorption studies for pesticides should be conducted, analysed and used in regulatory assessments
The EFSA Panel on Plant Protection Products and their Residues reviewed the guidance on how aged sorption studies for pesticides should be conducted, analysed and used in regulatory assessment. The inclusion of aged sorption is a higher tier in the groundwater leaching assessment. The Panel based its review on a test with three substances taken from a data set provided by the European Crop Protection
Association. Particular points of attention were the quality of the data provided, the proposed fitting procedure of aged sorption experiments and the proposed method for combining results obtained from aged sorption studies and lower-tier studies on degradation and adsorption. Aged sorption was a relevant process in all cases studied. The test revealed that the guidance could generally be well applied and resulted in robust and plausible results. The Panel considers the guidance suitable for use in the
groundwater leaching assessment after the recommendations in this Scientific Opinion have been implemented, with the exception of the use of field data to derive aged sorption parameters. The Panel noted that the draft guidance could only be used by experienced users because there is no software tool that fully supports the work flow in the guidance document. It is therefore recommended that a user-friendly software tool be developed. Aged sorption lowered the predicted concentration in groundwater. However, because aged sorption experiments may be conducted in different soils than
lower-tier degradation and adsorption experiments, it cannot be guaranteed that the higher tier predicts lower concentrations than the lower tier, while lower tiers should be more conservative than higher tiers. To mitigate this problem, the Panel recommends using all available higher- and lower-tier data in the leaching assessment. The Panel further recommends that aged sorption parameters for metabolites be derived only from metabolite-dosed studies. The formation fraction can be derived from parentdosed
degradation studies, provided that the parent and metabolite are fitted with the best-fit model, which is the double first-order in parallel model in the case of aged sorption