Temporal evolution of emerging contaminants, priority substances and heavy metals most frequently detected in reclaimed water and grounwater in a volcanic aquifer

[EN] The presence of emerging contaminants has been previously described in reclaimed water and groundwater of Gran Canaria (Spain). Despite of the environmental risk associated to irrigation with reclaimed water (R), this practice is necessary considering sustainability of the hydrological cycle in semiarid zones, especially regarding agricultural activity. The aim of this study was: i) to analyse the evolution during two years of contaminants of emerging concern, priority substances (2008/105/EC) and heavy metals in reclaimed water (R) and in a volcanic aquifer in the NE of Gran Canaria where a golf course has been irrigated with R since 1976 and ii) to relate this presence with physicochemical water properties and hydrogeological media. Reclaimed water and groundwater (GW) were monitoring quarterly from July 2009 to September 2011. Sorption and degradation processes in soil account for more compounds being detected in R. Diazinon and chlorfenvinphos were detected always in R and terbuthylazine, terbutryn and diuron at 90% of frequency. Considering all the samples, the most frequent compounds were chlorpyrifos ethyl, fluorene, phenanthrene and pyrene. Although their concentrations were frequently below 50 ngL-1, some contaminants, were occasionally detected at higher concentrations. Chlorpyrifos ethyl and diuron are priority substances detected frequently and at high concentrations so they must be included in monitoring studies. Geology and location seem to be related to the emerging compounds presence due to occasional contamination events (not related to R irrigation) and therefore not to an existence of a dangerous diffuse contamination level. Thus, it is preferable to select wells with less stable chemical water quality, in order to monitor the risk of emerging compounds presence. Considering the relationship between contaminant presence, chemical water quality, seasonal variation, hydrogeological characteristics and wells location we can conclude that chlorpyrifos ethyl and diuron were the most dangerous priority substances in terms of GW quality so they must be included in all of the monitoring studies, at least in Canary Islands.

Moluscos gasterópodos como bioindicadores en el Archipiélago canario: de procesos naturales a causas antropogénicas

Se han eliminado páginas en blanco

Dietary intake of environmentally persistent plaguicides in the european population

[EN] Global pollution has become one of the most important problems of the modern societies and pesticides play a major role among the chemical contaminants that are released to the environment every year. Organochlorine compounds have been widely used in the past all over the world as pesticides and some of them are still used for the control of vectors of infectious diseases. Due to their high lipophilicity, stability and resistance to degradation, most of them have been banned or strictly regulated but their levels remain high in the environment as persistent organic pollutants (POPs). Their presence in the environment leads to their introduction into the food chain, especially affecting food of animal origin with higher fat content. Due to their liposolubility, these substances tend to be bioaccumulated into the fat tissues of living beings along their entire lives, and to be biomagnificated across trophic levels in the food chain. Thus, the main human source of these pesticides comes from the daily intake of contaminated food from environmental sources. It has been established the role of many of the POPs as endocrine disruptors and even as carcinogenic agents, being thus considered as important risk factors for health. Moreover, chronic exposure to pesticides, even at very low levels, has been related with cancer, fertility problems, immunosuppression and other diseases. For this reason, it is important to know the level of POPs contamination and to identify the main sources contributing to it. Fish, meat and dairy products are the food groups with the highest levels of pollution. However, the residue levels vary by geographic area, and are influenced by several factors as food security policies, local pesticide use patterns, environmental practices, or the time when the study is conducted. Food habits, conditioned by different social and economic factors, as well as several biological factors (i.e. gender, sex and age), determine the levels of POPs exposure in the population. The purpose of this chapter is to give an overview of the dietary intake of environmentally persistent pesticides by the European population, and the potential adverse consequences of this exposure on human health.

Resultados preliminares de los análisis de contaminantes emergentes y sustancias prioritarias (2008/105/CE) en la red de control del Barranco de las Goteras (Gran Canaria)

[ES] En Gran Canaria, el uso de aguas regeneradas para el riego es una práctica utilizada desde hace más de treinta años, representando actualmente un 8% de los recursos hídricos utilizados (Consejo Insular de Aguas de Gran Canaria, com.per.). Recientemente y como respuesta al uso de aguas regeneradas, existe un creciente interés por la presencia de los denominados contaminantes emergentes en las aguas subterráneas y superficiales. Algunos son altamente móviles con potencial de lixiviación a las aguas subterráneas, mientras que otros se pueden acumular en la capa superior del suelo gracias a su capacidad adsorbente o son biodegradados en este medio. Los contenidos de algunas de estas sustancias en el agua son objeto de control atendiendo al listado de sustancias prioritarias de la Directiva 2008/105/CE. El objetivo de este estudio es analizar la situación en la zona del campo de golf de Bandama (NE de Gran Canaria), que ha sido regado con aguas regeneradas desde 1976, donde se ha establecido una red de control de agua de riego y agua subterránea, a partir de la que se están analizando sistemáticamente 185 compuestos emergentes y prioritarios.

Microextraction techniques coupled to liquid chromatography with mass spectrometry for the determination of organic micropollutants in environmental water samples

[EN]Until recently, sample preparation was carried out using traditional techniques, such as liquid–liquid extraction (LLE), that use large volumes of organic solvents. Solid-phase extraction (SPE) uses much less solvent than LLE, although the volume can still be significant. These preparation methods are expensive, time-consuming and environmentally unfriendly. Recently, a great effort has been made to develop new analytical methodologies able to perform direct analyses using miniaturised equipment, thereby achieving high enrichment factors, minimising solvent consumption and reducing waste. These microextraction techniques improve the performance during sample preparation, particularly in complex water environmental samples, such as wastewaters, surface and ground waters, tap waters, sea and river waters. Liquid chromatography coupled to tandem mass spectrometry (LC/MS/MS) and time-of-flight mass spectrometric (TOF/MS) techniques can be used when analysing a broad range of organic micropollutants. Before separating and detecting these compounds in environmental samples, the target analytes must be extracted and pre-concentrated to make them detectable. In this work, we review the most recent applications of microextraction preparation techniques in different water environmental matrices to determine organic micropollutants: solid-phase microextraction SPME, in-tube solid-phase microextraction (IT-SPME), stir bar sorptive extraction (SBSE) and liquid-phase microextraction (LPME). Several groups of compounds are considered organic micropollutants because these are being released continuously into the environment. Many of these compounds are considered emerging contaminants. These analytes are generally compounds that are not covered by the existing regulations and are now detected more frequently in different environmental compartments. Pharmaceuticals, surfactants, personal care products and other chemicals are considered micropollutants. These compounds must be monitored because, although they are detected in low concentrations, they might be harmful toward ecosystems.

Resistencia a antibióticos en bacterias aisladas de muestras de agua en Gran Canaria y su relación con la presencia de contaminantes emergentes

[ES]Hemos analizado la posible relación entre la presencia de contaminantes emergentes en agua regenerada para riego, agua del lixiviado del suelo y agua subterránea y la resistencia a antibióticos de las bacterias aisladas. Se tomaron muestras de agua. Cada muestra se dividió en dos partes. Una se centrifugó y se resembró en diferentes medios. Cincuenta mililitros de la segunda parte se añadieron a Caldo Brain Heart. En la siembra directa de agua de riego y solución del suelo se detectaron numerosas colonias. El crecimiento en la siembra directa de agua de galería fue escaso, y no hubo crecimiento cuando se sembró agua de pozo. Mediante enriquecimiento en Caldo BHI y resiembra posterior, se obtuvieron numerosas colonias

Long-term dietary exposure to lead in young European children: comparing a pan-European approach with a national exposure assessment

Long-term dietary exposures to lead in young children were calculated by combining food consumption data of 11 European countries categorised using harmonised broad food categories with occurrence data on lead from different Member States (pan-European approach). The results of the assessment in children living in the Netherlands were compared with a long-term lead intake assessment in the same group using Dutch lead concentration data and linking the consumption and concentration data at the highest possible level of detail. Exposures obtained with the pan-European approach were higher than the national exposure calculations. For both assessments cereals contributed most to the exposure. The lower dietary exposure in the national study was due to the use of lower lead concentrations and...