Inclusion of emerging organic contaminants in groundwater monitoring plans.

Groundwater is essential for human life and its protection is a goal for the European policies. All the anthropogenic activities could impact on water quality. •Conventional pollutants and more than 700 emerging pollutants, resulting from point and diffuse source contamination, threat the aquatic ecosystem.•Policy-makers and scientists will have to cooperate to create an initial groundwater emerging pollutant priority list, to answer at consumer demands for safety and to the lack of conceptual models for emerging pollutants in groundwater.•Among the emerging contaminants and pollutants this paper focuses on organic wastewater contaminants (OWCs) mainly released into the environment by domestic households, industry, hospitals and agriculture. This paper starts from the current regulatory framework and from the literature overview to explain how the missing conceptual model for OWCs could be developed.•A full understanding of the mechanisms leading to the contamination and the evidence of the contamination must be the foundation of the conceptual model. In this paper carbamazepine, galaxolide and sulfamethozale, between the OWCs, are proposed as "environmental tracers" to identify sources and pathways ofcontamination/pollution.

Avoiding social traps in the ecosystem stewardship: The Italian Fontanile lowland spring.

Fontanile is a Po Valley (Italy) quasi-natural lowland spring built in the middle age. This paper identifies options for the conservation of the Fontanile water dependent ecosystem, using scenarios and simulations, and exploring different policy options. Three modeling analysis have been performed: the first was carried out for estimating groundwater contamination and recharge from above, the second for evaluating the function of vegetative filter strip on the surface water quality and the last one for testing pesticide drift reduction due to the vegetative filter strip. Uncertainty characterization included climate change projections. Despite the nitrate concentration in water could favorite the eutrophication phenomena, this not occurs because of the low phosphate concentration in water and of the presence of arboreal shade. Therefore, the protection strategies must focus on sustaining desirable water quantity conditions. Water saving and conservation technologies that improve the agricultural productivity but reduce the Fontanile water flow and large buffer strips that have a limited efficacy due to the Fontanile hydrological settings can be judged as ecological traps. Inefficient irrigation systems, good agricultural practices, integrated pest management and arboreal filter strip can preserve the quality of those ecosystems.

Does groundwater protection in Europe require new EU-wide environmental quality standards?

The European Groundwater Directive could be improved by limiting the scopes of the Annexes I and II to the manmade and natural substances, respectively, and by defining a common monitoring protocol. The changes in the European landuse patterns, in particular the urban sprawl phenomena, obscure the distinction between the point and diffuse sources of contamination. In the future more importance will be given to the household contamination. Moreover, the agricultural environment could be used for developing new conceptual models related to the pharmaceuticals.

Development and field validation of an indicator to assess the relative mobility and risk of pesticides in the Lourens River catchment, South Africa.

A GIS based pesticide risk indicator that integrates exposure variables (i.e. pesticide application, geographic, physicochemical and crop data) and toxicity endpoints (using species sensitivity distributions) was developed to estimate the Predicted Relative Exposure (PREX) and Predicted Relative Risk (PRRI) of applied pesticides to aquatic ecosystem health in the Lourens River catchment, Western Cape, South Africa. Samples were collected weekly at five sites from the beginning of the spraying season (October) till the beginning of the rainy season (April) and were semi quantitatively analysed for relevant pesticides applied according to the local farmers spraying programme. Monitoring data indicate that physicochemical data obtained from international databases are reliable indicators of pesticide behaviour in the Western Cape of South Africa. Sensitivity analysis identified KOC as the most important parameter influencing predictions of pesticide loading derived from runoff. A comparison to monitoring data showed that the PREX successfully identified hotspot sites, gave a reasonable estimation of the relative contamination potential of different pesticides at a site and identified important routes of exposure (i.e. runoff or spray drift) of different pesticides at different sites. All pesticides detected during a monitored runoff event, were indicated as being more associated with runoff than spray drift by the PREX. The PRRI identified azinphos-methyl and chlorpyrifos as high risk pesticides towards the aquatic ecosystem. These results contribute to providing increased confidence in the use of risk indicator applications and, in particular, could lead to improved utilisation of limited resources for monitoring and management in resource constrained countries.

Herbicide contamination and dispersion pattern in lowland springs.

Herbicides reduce the diversity of flora and fauna in freshwater ecosystems and also contaminate groundwater due to leaching. Herbicide contamination can be a serious threat for all groundwater-dependent ecosystems (GDE), altering their chemical and biological quality. Successful management to protect GDE is dependent on detailed knowledge of the hydrogeological and hydrochemical features of the surrounding environment. We consider the possible diffuse contamination by herbicides of groundwater and of GDE as lowland springs, semi-artificial ecosystems with elevated biodiversity. The main objectives of the present work were thus: (1) to map herbicide contamination in lowland springs, (2) to evaluate the potential risk for biota and (3) to quantify the extent of the area from which the herbicide use can affect the water quality of lowland springs. In June and August 2009, nearly 23 springs within the Po River Plain (Northern Italy) were sampled and analyzed for five herbicides used to control weeds in maize. Hydrogeological properties, half-lives of the herbicides and their concentrations in both groundwater and springs were used to quantify the area from which the contamination could originate. Such evaluation was performed by means of GIS techniques. Terbuthylazine were the only herbicide found, together with its metabolite desethylterbuthylazine. In 16 out of 84 measurements, their concentrations were above the threshold for drinking water; however, they were always below the ecotoxicological end-points of aquatic flora and fauna. Spatial analyses reveal that the theoretical area from which herbicides can contaminate spring water is within a distance varying between a few and 1800 m. Our findings indicate that conservation plans should focus on the fields adjacent to or surrounding the springs and should address the optimization of irrigation practices, restoration of buffer strips, crop rotation and in general more sustainable agricultural practices in the proximity of these fragile GDE.

Exposure of the main italian river basin to pharmaceuticals.

This study give a preliminary survey of pharmaceutical contamination and accumulation in surface waters and sediments along the river Po basin (74,000 km(2), the largest in Italy), a strategic region for the Italian economy: it collects sewage from a vast industrialized area of Italy (Autorità di Baciono del fiume Po, 2006, 2009). 10 pharmaceuticals (atenolol, propanolol, metoprolol, nimesulide, furosemide, carbamazepine, ranitidine, metronidazole, paracetamol, and atorvastatin) from several therapeutic classes were searched in 54 sampling points along the river Po from the source to the delta, and at the mouth of its major effluents. In water samples were found pharmaceuticals in the range of 0.38-0.001 µg/L, except for furosemide (max conc. 0.605 µg/L), paracetamol (max conc. 3.59 µg/L), metoprolol (never detected) and for atenolol (not analysed). In sediment samples, only paracetamol was not detected, while the others were generally found in the range of 0.4-0.02 µg/kg ww with high concentrations for atenolol (max conc. 284 µg/kg ww) and furosemide (max conc. 98.4 µg/kg ww). The findings confirm also STPs as point sources of contamination. Despite of the much evidence for the adverse effects of pharmaceuticals in the aquatic environment, the observed low levels cannot be considered to pose a serious risk to human health; further studies are necessary for a comprehensive risk assessment.

Comments on pesticide risk assessment by the revision of Directive EU 91/414.

INTRODUCTION: Human health and the environment are major concerns for European Commission policy on the authorisation of plant protection products. The new regulation that revises and replaces the directive 91/414/EC moves towards the adoption of a Persistent Bioaccumulation Toxicity cutoff criterion because current pesticide risk assessment (PRA) is deterministic, based on few standard cases and therefore characterised by uncertainty. This revision could create concerns about sustainability. DISCUSSION: This paper analyses some effects of this directive on the agrochemical market and assumes new effects resulting from the introduction of the revision. Suggestions are made as to how pesticide risk assessment will have to adapt to answer the request of legislators on safety standards and sustainability, introducing probabilistic PRA. Toxicity and exposure functions will be fully characterised, producing distributions of predicted impact and quantifying the variability and uncertainty. For adopting PRA studies at the local/catchment scale, new assessment schemes will be necessary.

Pesticide risk management using indicators for vineyards in the central valley of Chile.

The Apalta catchment is a wine-producing area of 1300 ha, lying south of Santiago, located in the Colchagua Valley, near Santa Cruz in the VI Region of Chile. The vineyards are planted on slopes of up to 22 degrees, the rows being aligned mainly down the slope. This cropping system and its management lead to a potential contamination of natural resources. To assess the risk of environmental contamination due to the application of pesticides in different pest control strategies, indicators at a field level were derived according to a step-by-step procedure. Using these indicators, runoff was found to be the main process of impact. The different pest control strategies in this catchment caused different potential risks, though these in general were low.

The effect of crop rotation on pesticide leaching in a regional pesticide risk assessment.

New modeling approaches that include the use of GIS are under development in order to allow a more realistic assessment of environmental contamination by pesticides. This paper reports a regional GIS-based risk assessment using a software tool able to simulate complex and real crop rotations at the regional scale. A single pesticide leaching assessment has been done. The mean annual pesticide concentration in leachate has been analyzed using both stochastic and deterministic approaches. The outputs of these simulations were mapped over the sampling locations of the regional pesticide monitoring program, demonstrating that GIS-based risk assessment can be used to establish new monitoring programs. A multiple pesticide leaching assessment for analyzing the risk related to pest control strategies in six different maize-based rotations has been carried out. Additive toxic units approach has been used. Crop rotation allows to mediate the risk related to pesticide use because forces the use of different compounds with different fate and toxicology properties.

Prediction of agrochemical residue data on fruit using an informatic system (PARDIS model).

A 'step-by-step' method was used to develop a simplified procedure for calculating pesticide residue levels on fruit at harvest by considering the application of the compound and the relevant routes of loss. The model is applicable to cases where the most important exposure route is by direct spray to the canopy of the crop and where uptake into the plant by the roots can be disregarded. The exposure dose is calculated by considering the proportion of total crop cover represented by the fruits. The loss processes considered are photodegradation, uptake, volatilization and washoff. The outputs of the model were compared with measured residues of pesticides on pear. Analysis of the model fit demonstrates that the model predicted the measured data with a good level of accuracy for four of seven investigated pesticides. The predicted/observed quotients are close to 1, as is the modelling efficiency, and there are no great differences between the predicted and observed values. Taking into account the extreme simplicity of the model and the complexity of the environmental processes considered, these results encourage further research into the modelling of residue behaviour in food commodities. The objectives of this work were to produce a tool to predict pesticide residues in products of plant origin, to complement monitoring of pesticide levels and to be useful in evaluating the effect of government policies on food safety. All predicted values were below the maximum levels fixed for pesticide residues in pear, as amended in Council Directives 86/362/EEC and 90/642/EEC.

Deposition and dissipation of chlorpyrifos in surface water following vineyard applications in northern Italy.

Chlorpyrifos is an insecticide approved globally for use on a wide range of crops. Laboratory studies indicate that chlorpyrifos is toxic to fish and aquatic invertebrates, and so the adoption of practices that reduce aquatic exposure following use should be encouraged. This study assessed the exposure of surface water to the spray-drift of chlorpyrifos and the subsequent contamination of a realistic worst-case edge-of-field ditch in a vineyard in Northern Italy. Chlorpyrifos (DURSBAN 480 EC [Dow Elanco, Indianapolis, IN, USA]) was applied according to local Good Agricultural Practice (GAP) on two vineyard plots using atomizer equipment. Drift deposition and subsequent dissipation of chlorpyrifos were then monitored in an adjacent, common ditch, with an inherent buffer zone of approximately 7 m between the treated area and the ditch. The results showed that the drift loadings under the study conditions could reach predicted levels from standard spray-drift tables. However, the measured drift was highly variable due to physical factors such as the crop canopy and the distribution of vines within the rows. The amount of chlorpyrifos deposited onto the surface of the ditch water and intercepted by paper strips was approximately 2% of the applied amount after the two applications, with a maximum concentration of approximately 0.3 microg L(-1) immediately after the first application and 0.09 microg L(-1) after the second, which then dissipated from the water column within 12 to 24 h. The results showed that drift deposition spatially was variable and that chlorpyrifos residues dissipated rapidly from this surface water body. Both aspects are considered important in order to refine the aquatic risk assessment at a higher tier for both registration and management purposes.