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511.
The amount of waste produced and the control of separate collection are crucial issues for the planning of a territorial Integrated Waste Management System, enabling the allocation of each sorted waste fraction to the proper treatment and recycling processes. The present study focuses on assessing indicators of different waste management systems in areas characterized by different territorial conditions. The investigated case study concerns the municipalities of Emilia Romagna (northern Italy), which present a rather uniform socioeconomic situation, but a variety of geographic, urban and waste management characteristics. A survey of waste generation and collection rates was carried out, and correlated with the different territorial conditions, classifying the municipalities according to altitude and population density. The best environmental performances, in terms of high separate collection rate, were found on average in rural areas in the plain, while the lowest waste generation was associated with rural hill towns.  相似文献   
512.
The main physical and chemical controls on nitrogen (N) fluxes between the root zone and the water table were determined for agricultural sites in California, Indiana, Maryland, Nebraska, and Washington from 2004 to 2005. Sites included irrigated and nonirrigated fields; soil textures ranging from clay to sand; crops including corn, soybeans, almonds, and pasture; and unsaturated zone thicknesses ranging from 1 to 22 m. Chemical analyses of water from lysimeters and shallow wells indicate that advective transport of nitrate is the dominant process affecting the flux of N below the root zone. Vertical profiles of (i) nitrogen species, (ii) stable isotopes of nitrogen and oxygen, and (iii) oxygen, N, and argon in unsaturated zone air and correlations between N and other agricultural chemicals indicate that reactions do not greatly affect N concentrations between the root zone and the capillary fringe. As a result, physical factors, such as N application rate, water inputs, and evapotranspiration, control the differences in concentrations among the sites. Concentrations of N in shallow lysimeters exhibit seasonal variation, whereas concentrations in lysimeters deeper than a few meters are relatively stable. Based on concentration and recharge estimates, fluxes of N through the deep unsaturated zone range from 7 to 99 kg ha(-1) yr(-1). Vertical fluxes of N in ground water are lower due to spatial and historical changes in N inputs. High N fluxes are associated with coarse sediments and high N application rates.  相似文献   
513.
Environmental Science and Pollution Research - In this study, wastewater from municipal services, such as a port wastewater reception facility (PRF-WW) and a municipal solid waste plant (MSWP), was...  相似文献   
514.
Behavioral Ecology and Sociobiology - Colony size is an important predictor of annual survival and reproduction in social insects. By tracking monthly forager turn over, we measured the...  相似文献   
515.
Food allergy represents an increasing public health issue, and a large number of food control authorities have provided regulations aimed to minimize the risk of allergic reaction for sensitized consumers. The Food and Agriculture Organization of the United Nations together with the World Health Organization established the Codex Alimentarius Commission whose main goal is to protect the consumers’ health. To purse this task the Commission listed the foods and ingredients causing the most severe allergic reactions that should be labelled. It has been reported that some cases of specific foods hypersensitivity display a different prevalence among different Countries. Thus, the European Union drew up a list of mandatory allergens (that must be labelled) longer than that provided by Codex Alimentarius. As a consequence of the complexity of the legal phraseology of the European Union (EU) and/or European Community (EC) the Regulations and/or Directives were differently translated in all EC/EU official languages determining possible misinterpretations of the legislation. Moreover, food labelling regulations were also established with the goal to promote the consumers’ conscious choice about what they eat. Starting from the case of the fermented beverages, we analysed the European legislative scenario concerning the allergen labelling of the last fifteen years, highlighting that mistranslations, misinterpretations and lack of information in the EU Regulations might lead to health and ethical issues.  相似文献   
516.
We respond to the paper of Kruse-Plass et al. (Environ Sci Eur 29:12, 2017), published in this journal, regarding the risk to non-target lepidopteran larvae exposed to pollen from one or more of three Bt maize events (MON810, Bt11 and 1507). We emphasise that what is important for environmental risk assessment is not the number of pollen grains per se, but the degree of exposure of a NT lepidopteran larva to Bt protein contained in maize pollen. The main text of this response deals with general issues which Kruse-Plass et al. have failed to understand; more detailed refutations of each of their claims are given in Additional file 1. Valid environmental risk assessment requires direct measurement of pollen on leaves at varying distances outside a source field(s); such measurements reflect the potential exposure experienced by an individual larva on a host plant. There are no new data in the Kruse-Plass et al. paper, or indeed any data directly quantifying pollen on actual host-plant leaves outside a maize field; only data gathered within or at the edge of maize crops were reported. Values quoted by Kruse-Plass et al. for deposition on host plants outside the field were estimates only. We reiterate the severe methodological criticisms made by EFSA [Relevance of a new scientific publication (Hofmann et al. 2016) for previous environmental risk assessment conclusions and risk management recommendations on the cultivation of Bt-maize events MON810, Bt11 and 1507. EFSA Supp Publ; EN-1070, 2016], which render this estimation procedure unreliable. Furthermore, criticisms of EFSA (EFSA J 2015(13):4127, 2015) and of EFSA [Relevance of a new scientific publication (Hofmann et al. 2016) for previous environmental risk assessment conclusions and risk management recommendations on the cultivation of Bt-maize events MON810, Bt11 and 1507. EFSA Supp Publ; EN-1070, 2016] made by Kruse-Plass et al. are shown in Additional file 1 to be without foundation. We therefore consider that there is no valid evidence presented by Kruse-Plass et al. to justify their conclusions.  相似文献   
517.
Flood forecasts and warnings are intended to reduce flood‐related property damages and loss of human life. Considerable research has improved flood forecasting accuracy (e.g., more accurate prediction of the occurrence of flood events) and lead time. However, the delivery of improved forecast information alone is not necessarily sufficient to reduce flood damage and loss of life, as people have varying responses and reactions to flood warnings. This study develops an agent‐based modeling framework that evaluates the impacts of heterogeneity in human behaviors (i.e., variation in behaviors in response to flood warnings), as well as residential density, on the benefits of flood warnings. The framework is coupled with a traffic model to simulate evacuation processes within a road network under various flood warning scenarios. The results show the marginal benefit associated with providing better flood warnings is significantly constrained if people behave in a more risk‐tolerant manner, especially in high‐density residential areas. The results also show significant impacts of human behavioral heterogeneity on the benefits of flood warnings, and thus stress the importance of considering human behavioral heterogeneity in simulating flood warning‐response systems. Further study is suggested to more accurately model human responses and behavioral heterogeneity, as well as to include more attributes of residential areas to estimate and improve the benefits of flood warnings.  相似文献   
518.
Open burning for waste disposal is, in many countries, the dominant source of polychlorinated dibenzodioxins, dibenzofurans and biphenyls (PCDD/PCDF/PCB) release to the environment. To generate emission factors for open burning, experimental pile burns of about 100 kg of household waste were conducted with emissions sampling. From these experiments and others conducted by the same authors it is found that less compaction of waste or active mixing during the fire - “stirring” - promotes better combustion (as evidenced by lower CO/CO2 ratio) and reduces emissions of PCDD/PCDF/PCB; an intuitive but previously undemonstrated result. These experiments also support previous results suggesting PCDD/PCDF/PCB generation in open burning - while still highly variable - tends to be greater in the later (smoldering) phases of burning when the CO/CO2 ratio increases.  相似文献   
519.
Background, aim and scope

After the discovery of chloroform in drinking water, an extensive amount of work has been dedicated to the factors influencing the formation of halogenated disinfections by-products (DBPs). The disinfection practice can vary significantly from one country to another. Whereas no disinfectant is added to many water supplies in Switzerland or no disinfectant residual is maintained in the distribution system, high disinfectant doses are applied together with high residual concentrations in the distribution system in other countries such as the USA or some southern European countries and Romania. In the present study, several treatment plants in the Somes river basin in Romania were investigated with regard to chlorine practice and DBP formation (trihalomethanes (THMs)). Laboratory kinetic studies were also performed to investigate whether there is a relationship between raw water dissolved organic matter, residual chlorine, water temperature and THM formation.

Materials and methods

Drinking water samples were collected from different sampling points in the water treatment plant (WTP) from Gilau and the corresponding distribution system in Cluj-Napoca and also from Beclean, Dej and Jibou WTPs. The water samples were collected once a month from July 2006 to November 2007 and stored in 40-mL vials closed with Teflon lined screw caps. Water samples were preserved at 4°C until analysis after sodium thiosulfate (Na2S2O3) had been added to quench residual chlorine. All samples were analysed for THMs using headspace GC-ECD between 1 and 7 days after sampling. The sample (10 mL) was filled into 20-mL headspace vials and closed with a Teflon-lined screw cap. Thereafter, the samples were equilibrated in an oven at 60°C for 45 min. The headspace (1 mL) was then injected into the GC (Cyanopropylphenyl Polysiloxane column, 30 m × 53 mm, 3 μm film thickness, Thermo Finnigan, USA). The MDLs for THMs were determined from the standard deviation of eight standards at 1 μg/L. The MDLs for CHCl3, CHBrCl2, CHBr2Cl and CHBr3 were 0.3, 0.2, 0.3 and 0.6 μg/L, respectively. All kinetic laboratory studies were carried out only with water from the WTP Gilau. The experiments were conducted under two conditions: baseline conditions (pH 7, 21°C, 2.5 mg/L Cl2) to gain information about the change of the organic matter in the raw water and seasonally variable conditions to simulate the actual process at the treatment plant and the distribution system.

Results and discussion

This study shows that the current chlorination practice in the investigated plants complies with the THM drinking water standards of the EU. The THM concentrations in all samples taken in the four treatment plants and distributions systems were below the EU drinking water standard for TTHMs of 100 μg/L. Due to the low bromide levels in the raw waters, the main THM formed in the investigated plants is chloroform. It could also be seen that the THM levels were typically lower in water supplies with groundwater as their water resource. In one plant (Dej) with a pre-ozonation step, a significantly lower (50%) THM formation during post-chlorination was observed. Laboratory chlorination experiments revealed a good correlation between chloroform formation and the consumed chlorine dose. Also, these experiments allowed a semi-quantative prediction of the chloroform formation in the distribution system of Cluj-Napoca.

Conclusions

CHCl3 was the most important trihalomethane species observed after the chlorination of water in all of the sampled months. However, TTHM concentrations did not exceed the maximum permissible value of 100 μg/L (EU). The THM formation rates in the distribution system of Cluj-Napoca have a high seasonal variability. Kinetic laboratory experiments could be used to predict chloroform formation in the Cluj-Napoca distribution system. Furthermore, an empirical model allowed an estimation of the chloroform formation in the Gilau water treatment plant.

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520.
The effect of Pb + Zn on coelomocyte riboflavin content in the epigeic earthworm Dendrodrilus rubidus inhabiting three metalliferous soils and one reference soil was measured by flow cytometry and spectrofluorimetry. A reciprocal polluted↔unpolluted worm transfer experiment (4-week exposure) was also performed. High proportions of autofluorescent eleocytes were counted in worms from all localities, but intense riboflavin-derived autofluorescence was detectable only in reference worm eleocytes. Other findings were: (i) fluorophore(s) other than riboflavin is/are responsible for eleocyte autofluorescence in residents of metalliferous soils; (ii) riboflavin content was reduced in the eleocytes of worms transferred from unpolluted to metal-polluted soil; (iii) the riboflavin content of D. rubidus eleocytes is a promising biomarker of exposure; (iv) COII mitochondrial genotyping revealed that the reference population is genetically distinct from the three mine populations; (v) metal exposure rather than genotype is probably the main determinant of inter-population differences in eleocyte riboflavin status.  相似文献   
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