Polluted paradise: Occurrence of pesticide residues within the urban coastal zones of Santa Cruz and Isabela (Galapagos, Ecuador)

Although pesticides are frequently used for agriculture in the Galapagos Islands (Ecuador), there are, to date, no investigations of pesticide occurrences its coastal waters. We examined presence residues waters urban areas two islands archipelago using a repeated sampling design. Quantification was performed by solid-phase extraction, followed chemical analysis liquid chromatography-tandem mass spectrometry (LC-MS/MS) and gas chromatography-electron capture detector (GC-ECD). The diversity concentration Santa Cruz island were higher compared Isabela island. In total, sixteen detected, including three persistent organic pollutants. Carbendazim (23.93 ?g·L?1), cadusafos (4.74 DDT (2.99 diuron (1.61 ?g·L?1) aldrin (1.55 detected with highest concentrations between samples. Repetitions locations show that varied considerably space time. Comparison local products indicated agricultural activities on as possible source. Furthermore, evaluation through ecological risk quotients showed observed levels seven pose relatively high biotic groups (i.e. algae, invertebrates fishes). Taken together, this study provides insights into need regulate, monitor assess islands. At global scale, is moreover valuable many facing same challenges.