Pesticides in the Ebro River basin: Occurrence and risk assessment

Abstract

In this study, 50 pesticides were analyzed in the Ebro River basin in 2010 and 2011 to assess their impact in water, sediment and biota. A special emphasis was placed on the potential effects of both, individual pesticides and their mixtures, in three trophic levels (algae, daphnia and fish) using Risk Quotients (RQs) and Toxic Units (TUs) for water and sediments. Chlorpyrifos, diazinon and carbendazim were the most frequent in water (95, 95 and 70% of the samples, respectively). Imazalil (409.73 ng/L) and diuron (150 ng/L) were at the highest concentrations. Sediment and biota were less contaminated. Chlorpyrifos, diazinon and diclofenthion were the most frequent in sediments (82, 45 and 21% of the samples, respectively). The only pesticide detected in biota was chlorpyrifos (up to 840.2 ng g(-1)). Ecotoxicological risk assessment through RQs showed that organophosphorus and azol presented high risk for algae; organophosphorus, benzimidazoles, carbamates, juvenile hormone mimic and other pesticides for daphnia, and organophosphorus, azol and juvenile hormone mimics for fish. The sum TUsite for water and sediments showed values < 1 for the three bioassays. In both matrices, daphnia and fish were more sensitive to the mixture of pesticide residues present.

Pesticide residues in water, sediment and fish from Tono Reservoir and their health risk implications

“…For example, benthic fish species are considered more prone to contamination (Yim et al 2005; Wei et al 2014), as they tend to accumulate sediments bound contaminants than pelagic fish (Qadir and Malik 2011; Ccanccapa et al 2016). …”

How water quality standards for pesticides affect the classification of the chemical status of rivers

“…For example, the chemical status of the Boiron River was mainly defined as good at S2 and S3 when using the revised WQC whereas it was characterized as poor to very poor when using the historical standard. In addition, aquatic species have been shown to be sensitive to the concentration of pollution (see e.g., Ccanccapa, Masiá, Navarro-Ortega, Picó, & Barceló, 2016;Milano et al, 2018;Palma et al, 2018). The quality of the river in terms of nutrient and pesticide concentration is an important stress factor for aquatic organisms, whose sensitivity to pollution often follows a log-normal distribution (Nagai, 2016).…”

“…Current ecotoxicological studies mainly focus on the short-term effects (e.g., Ccanccapa et al, 2016;Papadakis et al, 2018). Recent advanced studies highlight the fact that the environmental toxicity of long term exposure can affect hatching and the viability of aquatic organisms (Gambardella et al, 2018;Jessen Rasmussen, Reiber, Holmstrup, & Liess, 2017) but many uncertainties still remain.…”

An update of the Worldwide Integrated Assessment (WIA) on systemic insecticides. Part 1: new molecules, metabolism, fate, and transport

“…In 2-year surveys of three major agricultural basins of Spain, imidacloprid was found in 17-58% of the samples from the Guadalquivir River (range 1.8-19.2 ng/L) (Masiá et al 2013), in 37-45% of water samples from the Ebro River (range 1.1-15 ng/L) (Ccanccapa et al 2016), and in 64-78% of the samples from the Llobregat River (range 2.1-66.5 ng/L) (Masiá et al 2015), with the highest concentrations in all three basins corresponding to the second year of the survey. In a rural area dominated by forests and arable land in Central Germany, 19 streams were monitored for pesticide contamination using passive samples (Chemcatcher).…”