Pesticide concentrations in the waters from a section of the Guadalquivir River Basin, Spain

Abstract

When surface water is used to supply urban settlements, exhaustive studies of the composition of the source are necessary to ensure its potability, and to assess the possible environmental effects associated with contamination by pesticides. The present study centers on the pesticide content of the waters from a section of the Guadalquivir River and its affluents in southern Spain. At many of the sampling points analyzed, high concentrations of both organochlorine and organophosphorus pesticides were detected. The presence of these toxic substances in dangerously high concentrations, as well as the linear tendency of the mean values for total pesticide concentration at sampling points, allows us to conclude that the agricultural character of this area has ultimately contributed to the contamination of the Guadalquivir River and its affluents, creating a sanitary and ecological hazard. In some cases the levels of contamination were found to consistently exceed the limits established by the European Union concerning water quality for human consumption. Because the substances analyzed are not eliminated through conventional water treatment methods, we conclude that the sampled section of the Guadalquivir River basin should not be currently used as a source of water for human consumption. Both pretreatment and advanced water treatment techniques would be required to reduce micropollutant concentrations to potable levels. ©1997 by John Wiley & Sons, Inc. Environ Toxicol Water Qual 12: 249–256, 1997

Using water industry data to assess the metaldehyde pollution problem

“…The maximum concentration detected was 2.72 μg/L which is of the same order of magnitude as reported in the few other existing studies that have monitored metaldehyde in waters (NFU 2011;Lazartigues et al, 2012). Despite the very small number of published studies, it appears that metaldehyde represents a very significant water quality concern, having already been found at concentrations as high as other pesticides that have previously been monitored in rivers and deemed to be problematic (Espigares et al 1997;Power et al 1999;Brown et al 2002;Du Preez et al 2005). For instance, these concentrations are of the same order of magnitude as the highest reported in the study by Brown et al (2002) who used a comprehensive pesticide monitoring database comprising of over 1.5 million analyses undertaken in the United Kingdom between 1992 and 1998 by the Environment Agency and water utilities.…”

Influence of Contamination by Organochlorine Pesticides and Polychlorinated Biphenyls on the Breeding of the Spanish Imperial Eagle (Aquila adalberti)

“…Spanish Imperial Eagles from Doñana showed higher contamination levels than those from the rest of its distribution range. The predominant ecosystem in Doñana is wetlands, largely transformed into rice fields with an intense use of pesticides [9,43]. It also is situated at the mouth of the Guadalquivir River, which receives agricultural and industrial contaminants from a wide and extensive hydrographical basin [43,44].…”

“…The predominant ecosystem in Doñana is wetlands, largely transformed into rice fields with an intense use of pesticides [9,43]. It also is situated at the mouth of the Guadalquivir River, which receives agricultural and industrial contaminants from a wide and extensive hydrographical basin [43,44]. Crop area in the low stretches of the Guadalquivir River notably increased from 49.8 to 80.2% between 1958 and 1979, and the percentage of crops with pesticide use increased from 38 to 98% in the same period [45].…”

“…Crop area in the low stretches of the Guadalquivir River notably increased from 49.8 to 80.2% between 1958 and 1979, and the percentage of crops with pesticide use increased from 38 to 98% in the same period [45]. Considering that OC contaminants are found in eggs of all birds from Doñana tested to date [9,[21][22][23] in waters and sediments of low stretches of the Guadalquivir River, in which the detected quantities of DDE preclude human consumption [43], the entry of contaminants into the ecosystem of Doñ ana is likely to be aquatic. Spanish Imperial Eagles from Doñana, in contrast to other populations, include an important percentage of waterfowl in their diet, both during the breeding season (47.3%) as well as during the nonbreeding season (27.8%) [11].…”

“…Levels in Doñana, however, were still high in 1996. Dichlorodiphenyltrichloroethane still seems to be used at present in this area, as some studies suggest [43], and DDT is present in legal products, such as dicofol (Kelthane; Bayer Crop Science, Tarragona, Spain), in significant quantities [46]. Additionally, the high DDE levels found in 1996 coincide with the year subsequent to the DDT ban, which may indicate that the ban could motivate, at least in the short term, the opposite effect, having possibly encouraged the fast use of those stocks that had been in storage until then.…”