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Marco Vighi

Publications and source records attributed to Marco Vighi.

12 recordsLinked to original sources
PubMed2006

Evaluating the fate of p,p'-DDT in Tianjin, China using a non-steady-state multimedia fugacity model.

Studies showed that DDT levels were still high in Tianjin, China, even though its use was banned in 1983. To estimate current risk of DDT to human health in Tianjin area, a non-steady-state (Level IV) multimedia fugacity model was used to simulate the fate and transfer of p,p'-DDT before and after the ban. The ordinary linear equations of Level IV model were solved with a matrix approach. The calculated p,p'-DDT concentration in air, water, soil, and sediment reached a maximum in the 1980s and then decreased, and agree well with those measured. The biggest bulk sinks of p,p'-DDT were soil and sediment, which accounted for 90% of total amount of p,p'-DDT in the environment. Air deposition and diffusions through the interfaces of water-air and water-sediment were the major intermedia transfer processes, while the degradation in soil and sediment were the key eliminating routes for p,p'-DDT in the environment.

Air↗
PubMed2006

The evolution of the Environmental Quality concept: from the US EPA Red Book to the European Water Framework Directive.

BACKGROUND: Water Quality Criteria were firstly defined in the 1970s by the EPA in the USA and the EIFAC in Europe, recognizing the need for protecting water quality in order to allow the use of water resources by man. In the 1990s, the European Commission emphasized the importance of safeguarding structure and function of biologic communities. These approaches were chemically-based. The European Water Framework Directive (WFD) substantially changes the concept of Water Quality, by assuming that a water body needs to be protected as an environmental good and not as a resource to be exploited. In this frame, the biological-ecological quality assumes a prevailing role. MAIN FEATURES: The Water Quality concept introduced by the WFD is a challenge for environmental sciences. Reference conditions should be defined for different typologies of water bodies and for different European ecoregions. Suitable indicators should be developed in order to quantify ecological status and to define what a 'good' ecological status is. Procedures should be developed for correlating the deviation from a good ecological to the effects of multiple stressors on function and structure of the ecosystem. The protection of biodiversity becomes a key objective. In this frame, the traditional procedures for ecotoxicological risk assessment, mainly based on laboratory testing, should be overcome by more site-specific approaches, taking into account the characteristics and the homeostatic capabilities of natural communities. In the paper an overview of the present knowledge and of the new trends in ecotoxicology to get these objectives will be given. A procedure is suggested based on the concept of Species Sensitivity Distribution (SSD). RECOMMENDATIONS AND PERSPECTIVES: The need for more site-specific and ecologically-oriented approaches in ecotoxicology is strongly recommended. The development of new tools for implementing the concept of 'Stress Ecology' has been recently proposed by van Straalen (2003). In the same time, more 'cological realism' is needed in practically applicable procedures for regulatory purposes.

Animals↗
PubMed2005

Organochlorine compounds in ice melt water from Italian Alpine rivers.

Organochlorine chemicals (OCs) (dichlorodiphenyltrichloroethanes, hexachlorocyclohexanes, and hexachlorobenzene) were measured in ice melt water from five glaciers in the Italian Alps. Even though the data collected may not be sufficient for a precise description of persistent organic pollutant release patterns from glacier melting, they have, however, highlighted the potential for surface water contamination. Concentrations were of the same order of magnitude in all glacial streams, indicating comparable contamination levels in different glaciers of the alpine region. OC levels in nonglacial springs sampled in the same areas are usually lower. Even if differences during the melting season (from spring to autumn) have been identified, a regular seasonal pattern in OC concentrations was not observed. Risk for the aquatic environment is excluded through direct water exposure, but it is likely to occur through biomagnification and secondary poisoning exposure.

Environmental Monitoring↗
PubMed2005

Analysis of a firn core for assessing POP seasonal accumulation on an Alpine glacier.

Organochlorine pesticides (DDTs, HCHs, HCB) and selected PCBs were analyzed in samples from a firn core drilled on the Lys Glacier (4240 m above sea level, Monte Rosa Group, Italian Alps) in Summer 2000. The samples covered a relatively short time interval (from 1997 to 2000) and a seasonal detail breakdown was possible. A probable seasonal trend was observed only for gamma-HCH, a pesticide currently used in some European countries. For all other chemicals, a seasonal trend was not evident, and this supports the hypothesis of the prevailing role of long-range transport in comparison with local emissions for POP pollution in high mountains. The role of temperature on air-snow exchange has also been highlighted.

Environmental Monitoring↗
PubMed2004

Quantitative inter-specific chemical activity relationships of pesticides in the aquatic environment.

Inter-species correlations could be a useful tool for predicting toxicity and for establishing sensitivity ratios among species. In this paper, quantitative inter-specific chemical activity relationships (QICAR) for aquatic organisms were developed to verify if such an approach could be utilised for estimating toxicological data when no other information is available. Inter-specific toxicity relationships on fish, Daphnia and algae were performed for pesticides considering a large data set (more than 600 compounds) and grouping the data either on a functional (herbicides, fungicides and insecticides) or chemical class base. Good correlations were found between several fish species and they were improved by excluding, from the data set, highly specific compounds such as organophosphorus insecticides. Relationship between fish (rainbow trout) and Daphnia was significant for the whole data set, but clearly improves if congeneric classes of pesticides are considered. The most significant results were found for azoles (fungicides) and for all data set of pesticides with the exclusion of organophosphorus and carbamate insecticides. As expected, toxicity on algae does not correlate either with fish or with Daphnia on the whole data set, but excluding the classes acting specifically toward one organism (insecticides and several classes of herbicides), good relationships were found. The analysis of the data permits the conclusion that the specificity in the mode action of pesticides is the key parameter for expecting or not inter-specific relationships. By the relative specificity of action of a group of compounds towards two species, the probability of obtaining a QICAR for this group can be derived. In general, compounds acting with the same level of specificity towards two different species, have a higher probability of showing inter-specific relationships and the lower the specificity of the mode of action of the compounds (e.g. narcotics or less inert chemicals), then the stronger are the relationships.

Animals↗
PubMed2004

Coumaphos distribution in the hive ecosystem: case study for modeling applications.

Pesticides are currently used inside hives, against the honeybee parasite Varroa destructor, producing unwanted contamination effects. To assess the distribution and fate of one of these pesticides (coumaphos), two experimental hives were treated with Perizin (the commercial product containing the active ingredient coumaphos). Samples of honey, wax, pollen, adult bees and larvae taken before treatment and up to 104 days afterwards, showed diffuse contamination. Wood hedges and wax bridges, where the pesticide solution was applied, were analysed as well. A mass balance was calculated, yielding a recovered amount of around 60% just after treatment and 38% 1 month later. Directly contaminated surfaces and wax contained the highest amount of residues. Wax and honey contained different amounts (10, and 0.1% respectively) but both retained residues for long time. Bees ingest most of the product just after treatment, then rapidly eliminate it by metabolism, advection and deposition processes. On the basis of analytical results, a simple model (level I of the fugacity model) was applied to the hive system for different pesticides (coumaphos, malathion, fluvalinate and bromopropylate). Predicted concentrations in wax and honey were compared with those measured, indicating the good predictive capability of this approach.

Animals↗
PubMed2004

Joint algal toxicity of phenylurea herbicides is equally predictable by concentration addition and independent action.

Photosynthesis-inhibiting phenylurea derivatives, such as diuron, are widely used as herbicides. Diuron concentrations clearly exceeding the predicted-no-effect concentration have been regularly measured in European freshwater systems. The frequently observed exposure to mixtures of phenylureas additionally increases the hazard to aquatic primary producers. Fluctuating numbers and concentrations of individual toxicants make experimental testing of every potential mixture unfeasible. Thus, predictive approaches to the mixture hazard assessment are needed. For this purpose, two concepts are at hand, both of which make use of known toxicities of the individual components but are based on opposite mechanistic suppositions: Concentration addition is based on the idea of similar mechanisms of action, whereas independent action assumes dissimilarly acting mixture components. On the basis of pharmacological reasoning, it was therefore anticipated that the joint algal toxicity of phenylurea mixtures would be predictable by concentration addition. Indeed, we could demonstrate a high predictive power of concentration addition for these combinations. Surprisingly, however, the opposite concept of independent action proved to be equally valid, because both concepts predicted virtually identical mixture toxicities. This exceptional case has previously been derived from theoretical considerations. Now, the tested phenylurea mixtures serve as an example for the practical relevance of this situation for multicomponent mixtures.

Chlorophyta↗
PubMed2003

Pesticide risk assessment in a lagoon ecosystem. Part I: exposure assessment.

This work is the first step of a research project on pesticide risk assessment for a coastal lagoon ecosystem (Orbetello lagoon, central Italy). Pesticide exposure was evaluated by means of predictive and experimental approaches. Predicted environmental concentrations (PECs) for water and sediments were estimated using fugacity-based multimedia models. Pesticide loads were quantified through a study of the use to which agricultural land was put in the study area. Multimedia fate models were used to predict the environmental concentration of 29 active ingredients (mainly insecticides and herbicides) selected among the most widely used within the catchment basin. Worst-case environmental scenarios were developed for the application of these models, in agreement with the precautionary principle. Experimental monitoring was performed on 10 selected chemicals. To assess the value and limitations of predictive and experimental approaches, calculated PECs and monitoring results were compared and discussed. Combined modeling and monitoring approaches have been found to be the best way to date to assess proper exposure.

Ecosystem↗
PubMed2003

Pesticide risk assessment in a lagoon ecosystem. Part II: effect assessment and risk characterization.

Ecotoxicological risk assessment for pesticides was performed on a coastal lagoon ecosystem (Orbetello lagoon, central Italy) according to the procedure described in the European technical guidance document (TGD) on risk assessment for new and existing substances. The procedure was applied to individual chemicals and to a mixture of chemicals with the same toxicological mode of action. Biomarker studies, measuring acetylcholinesterase (AchE) activity inhibition, were conducted on Zosterisessor ophiocephalus to compare the results of theoretical risk assessment with experimental measurements of ecotoxicological stress. Value and limitations of the risk assessment procedure and its application to site-specific environmental conditions are discussed. A tool crop risk index (CRI) for assessing the overall impact of pesticide use on a crop is proposed.

Acetylcholinesterase↗
PubMed2002

GIS-based system for surface water risk assessment of agricultural chemicals. 1. Methodological approach.

A methodology to develop a GIS-based system for the surface water risk assessment of agricultural chemicals is described. It is based on the integration of relational and spatial databases, GIS incorporating raster and vector, mass balance models, and pesticide risks indicators. Surface water pollution was modeled by taking into account two main processes: the load due to drift and the load due to a rainfall-runoff event. The former is immediately consequent to pesticide application; the second occurs a short period afterward. Thus two distinct PEC (predicted environmental concentration) values were estimated, differing in time. A pilot approach was applied to the herbicide alachlor on corn in Lombardia region (northern Italy) and represents the first stage of a wider project. Although the resultant alachlor PEC and risk maps represent a static image of a worst-case simulation, the main objective was to provide information for the territory with respect to relative risks at the watershed level, which is important in managing risks to the aquatic environment. The driving forces and spatial variability of the above-mentioned processes were investigated to improve knowledge about the territory and to indicate the need for more detailed site-specific studies.

Agriculture↗
PubMedDate not supplied

QSAR in ecotoxicity: an overview of modern classification techniques.

This study deals with classification for toxicity prediction. Using a data set of 235 pesticides and 153 descriptors, we built several models using seven classification algorithms: nearest mean classifier, linear discriminant analysis, quadratic discriminant analysis, regularized discriminant analysis, soft independent modeling of class analogy, K nearest neighbors classification, classification, and regression tree. The performance of the models was then compared with the classifier, the end-points, the number of descriptor, and the diversity of the data set. Finally, we made a critical analysis of the models and descriptors.

Algorithms↗