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151.

Background

Polychlorinated biphenyls (PCBs) and organochlorine pesticides are common environmental contaminants that have been associated with human health problems.

Objectives

To assess serum concentrations of several organochlorine contaminants in general population living in a city with an ancient agricultural tradition and to identify possible exposure sources in Sicily.

Methods

A cross-sectional study was conducted on 101 individuals. Each participant answered a face-to-face questionnaire submitted by well-trained personnel and provided a serum sample which was analyzed for the concentrations of PCBs, HCB, HCHs and DDTs by using gas-chromatography coupled with mass spectrometry.

Results

HCB, p,p′-DDE, PCB 138, PCB 153 and PCB 180 were detected in more than 80% of the study participants. The ng g−1 lipid median concentrations were: 18.6 for HCB; 175.1 for p,p′-DDE; 22. for PCB 138; 32.5 for PCB 153 and 23.0 for PCB 180. PCB 153 and PCB 138, PCB 138 and PCB 180, PCB 153 and PCB 180, and p,p′-DDE and HCB showed a high correlation each other (p < 0.05). HCB and p,p′-DDE concentrations were significantly higher in subjects >49 years old (adj-p = 0.03 in 50-69 years old and adj-p < 0.001 in >69 years old, respectively) whereas PCB 138, PCB 153 and PCB 180 concentrations were higher in males (adj-p = 0.03), in subjects >69 years old (adj-p = 0.04) and in current smokers (adj-p = 0.04).

Conclusions

The present study shows that serum concentrations of organochlorine compounds detected in subjects living in a small Sicilian city with ancient agricultural tradition are similar to those found in subjects living in urban areas of other countries. However, further investigations are needed to compare data from rural/urban areas in the same country, assessing correlations between serum concentrations of several chemical compounds and potential health effects in general population.  相似文献   
152.
The ecological apparency hypothesis in ethnobotanical studies predicts that the apparent plants (i.e., the most easily found in the vegetation) would be the most commonly collected and used by people. To test this hypothesis, it has been used the concept of use value (VU), which measures the relative importance of useful plants for a group of people. However, the use value has got some limitations, including the fact that it does not distinguish "current use" (plants which are effectively used) from "potential use" (well known plants, however not used). Therefore, this study has tested whether the obtained results through three different use value calculations could be useful in testing the ecological apparency hypothesis. These calculations have included the current use value, the potential use value, and the general use value. It has been carried out a vegetation survey and an interview for residents from the rural communities from Barrocas and Cachoeira (Soledade, Paraíba, Brazil). It has been used Spearman's coefficient to correlate phytosociological and ethnobotanical data. It has been observed that phytosociological parameters in Cachoeira were not correlated with any of the use values calculations, except the relationship between the current use value and the relative dominance (r(s)?=?0.57; p?相似文献   
153.
154.
Abstract

In this study, we used two biochars (BC) produced from grapevine pruning residues (BCgv) and red spruce wood (BCrs), two hydrochars (HC) from urban pruning residues (HCup) and the organic fraction of municipal solid wastes (HCuw), and two vermicomposts (VC) obtained vermicomposting digestates from buffalo manure (VCbm) and mixed feedstock (VCmf). Adsorption kinetics and isotherms of metribuzin onto these materials were performed. Sorption kinetics followed preferentially a pseudo-second-order model, thus indicating the occurrence of chemical interactions between the sorbate and the adsorbents. Adsorption constants were calculated using the Freundlich and Langmuir models. Metribuzin sorption data on BCgv and both HC fitted preferentially the Freundlich equation, whereas on the other materials data fitted both isotherms well (r?>?0.95). Metribuzin sorption capacity of the materials followed the trend BC?>?HC?>?VC. Sorption constants of metribuzin normalised per organic carbon content (KOC) on BCgv, BCrs, HCup, HCuw, VCbm and VCmf were 561, 383, 251, 214, 102 and 84?L kg?1, respectively. A significant positive correlation (P?=?0.016) was calculated between distribution coefficients (Kd) of all materials and the corresponding organic carbon contents, thus indicating a prominent role of the organic fraction of these materials in the adsorption of metribuzin.  相似文献   
155.
The experiment was carried out on a short rotation coppice culture of poplars (POP-EUROFACE, Central Italy), growing in a free air carbon dioxide enriched atmosphere (FACE). The specific objective of this work was to study whether elevated CO(2) and fertilization (two CO(2) treatments, elevated CO(2) and control, two N fertilization treatments, fertilized and unfertilized), as well as the interaction between treatments caused an unbalanced nutritional status of leaves in three poplar species (P. x euramericana, P. nigra and P. alba). Finally, we discuss the ecological implications of a possible change in foliar nutrients concentration. CO(2) enrichment reduced foliar nitrogen and increased the concentration of magnesium; whereas nitrogen fertilization had opposite effects on leaf nitrogen and magnesium concentrations. Moreover, the interaction between elevated CO(2) and N fertilization amplified some element unbalances such as the K/N-ratio.  相似文献   
156.
Two methods were used to calculate the meteorologically adjusted ground level ozone trends in southern Taiwan. The first method utilized is a robust linear regression method. The second approach uses a multilayer perceptron (MLP) artificial neural network (ANN) method. The observations obtained from 16 monitoring stations were analyzed and divided into six groups by hierarchical divisive clustering procedure. The daily maximum 1 and 8 h ozone concentrations for each group are then calculated. The meteorologically adjusted trends obtained by linear regression and MLP methods are smaller than the unadjusted trends for all groups and average time. It indicts that the meteorological conditions in Taiwan tend to increase ambient ozone concentrations in recent years.  相似文献   
157.
158.
Herbicide contamination of surficial groundwater in Northern Italy   总被引:1,自引:0,他引:1  
Data on herbicide pollution in groundwater are rather scarce; monitoring data are based on single investigation, focussing on limited area and on few compounds of interest. The large number of approved active ingredients (approximately 600 chemicals) makes difficult to obtain an accurate and actual information on herbicide application in different countries, even if herbicides are the second most important class of pesticides used in the European Union. The results of a two-year monitoring campaign undertaken in two areas intensively cultivated at Lombardy, Northern Italy, showed a diffuse groundwater contamination due to active ingredients and their metabolites. More than 50% of samples overcame M.A.C. and the most common herbicides were Atrazine, Terbuthylazine and Metolachlor, while DEA and DET metabolites were often characterized by greater concentrations than their relative active principles.  相似文献   
159.
A preliminary investigation has been carried out on the occurrence and effects of antibiotics used in Italian aquaculture with the objective of identifying priorities for monitoring programmes. According to the information available on the most pertinent and diffuse fish diseases and their related therapies, the presence of flumequine and oxytetracycline in sediments sampled from two trout farms and three sea-bass farms and in their surrounding environments was selected for an analytical investigation. The concentrations of oxytetracycline and flumequine varied up to a maximum of 246.3 and 578.8 microg/kg d.w., respectively. Flumequine was seen to have the highest toxicity in a bioluminescence assay with EC50 values varying within the range of 12-15 mg/l, while the EC50 values for oxytetracycline were within the range of 121-139 mg/l. The results of the present study indicate flumequine and oxytetracycline as priority chemicals to be monitored for possible environmental side effects of aquaculture in Italy. Apart from peak concentrations the chronic presence of flumequine and oxytetracycline in sediments both inside and outside farms should also be considered. In spite of the potential risks related to the use of antibiotics, the concentrations found in the sediments of the studied fish farms are significantly lower than those found in other areas.  相似文献   
160.
The food supply chain is affected by losses of products near to their expiry date or damaged by improper transportation or production defects. Such products are usually poorly attractive for the consumer in the target market even if they maintain their nutritional properties. On the other hand undernourished people face every day the problem of fulfilling their nutritional needs usually relying on non-profit organizations. In this field the food recovery enabling economic benefits for donors is nowadays seen as a coherent way to manage food products unsalable in the target market for various causes and thus destined to be discarded and disposed to landfill thus representing only a cost. Despite its obvious affordability the food recovery is today not always practiced because the economic benefits that could be achieved are barely known. The paper aims at presenting a deterministic mathematical model for the optimization of the supply chain composed by retailers and potential recipients that practice the food recovery, taking into account the benefits recognized to donors and the management costs of the food recovery. The model determines the optimal time to withdraw the products from the shelves as well as the quantities to be donated to the non-profit organizations and those to be sent to the livestock market maximizing the retailer profit. The results show that the optimal conditions ensuring the affordability of the food recovery strategy including the tax reliefs and cost saving for the retailers outperforms the profit achievable in absence of such a system.  相似文献   
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