Cintia Flores

Occurrence of perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) in N.E. Spanish surface waters and their removal in a drinking water treatment plant that combines conventional and advanced treatments in parallel lines.

Perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) are two emerging contaminants that have been detected in all environmental compartments. However, while most of the studies in the literature deal with their presence or removal in wastewater treatment, few of them are devoted to their detection in treated drinking water and fate during drinking water treatment. In this study, analyses of PFOS and PFOA have been carried out in river water samples and in the different stages of a drinking water treatment plant (DWTP) which has recently improved its conventional treatment process by adding ultrafiltration and reverse osmosis in a parallel treatment line. Conventional and advanced treatments have been studied in several pilot plants and in the DWTP, which offers the opportunity to compare both treatments operating simultaneously. From the results obtained, neither preoxidation, sand filtration, nor ozonation, removed both perfluorinated compounds. As advanced treatments, reverse osmosis has proved more effective than reverse electrodialysis to remove PFOA and PFOS in the different configurations of pilot plants assayed. Granular activated carbon with an average elimination efficiency of 64±11% and 45±19% for PFOS and PFOA, respectively and especially reverse osmosis, which was able to remove ≥99% of both compounds, were the sole effective treatment steps. Trace levels of PFOS (3.0-21 ng/L) and PFOA (<4.2-5.5 ng/L) detected in treated drinking water were significantly lowered in comparison to those measured in precedent years. These concentrations represent overall removal efficiencies of 89±22% for PFOA and 86±7% for PFOS.

Evaluation of tetrodotoxins in puffer fish caught along the Mediterranean coast of Spain. Toxin profile of Lagocephalus sceleratus

Abstract Although consumption of Tetraodontidae species is prohibited in the EU, intoxications are still reported. The evaluation of tetrodotoxins (TTXs) by mass spectrometry (LC‐MS/MS and LC‐HRMS) and a screening immunoassay (mELISA) in tetraodontid fishes caught along the Western Mediterranean Sea revealed high concentrations of TTXs in Lagocephalus sceleratus while no TTXs were identified in L. lagocephalus and Sphoeroides pachygaster individuals. The high TTXs content found in the L. sceleratus analysed herein demonstrate the occurrence of highly toxic puffer fish in the Western Mediterranean Sea. Being L. sceleratus a recent invasive species in the Mediterranean, surveillance, risk assessment and risk management measures are necessary. The strategy used within this research work could be a valuable tool for future food safety monitoring. Graphical abstract Presence of tetrodotoxins (TTXs) in different puffer fish species caught off the Spanish coast (Western Mediterranean Sea) was evaluated by liquid chromatography coupled to mass spectrometry (LC‐MS/MS). The only toxic species was Lagocephalus sceleratus, a recently invasive species in the Mediterranean. The toxin profile was confirmed by high resolution mass spectrometry (LC‐HRMS). An immunoassay (mELISA) also showed TTX presence, providing complementary functional information. Figure. No Caption available. HighlightsThis is the first toxicity assessment of the Lessepsian migrant pufferfish Lagocephalus sceleratus from the Spanish coast.This is the first report dealing with quantification of 11 tetrodotoxin analogues in various organs of L. sceleratus.Excellent correlation of LC‐MS/MS, LC‐HRMS and mELISA is obtained in the analysis of puffer fish samples.A user‐friendly screening and quantification analysis tool for tetrodotoxin is provided.

Identification of ciguatoxins in a shark involved in a fatal food poisoning in the Indian Ocean

Severe food poisoning events after the consumption of sharks have been reported since the 1940s; however, there has been no clear understanding of their cause. Herein, we report for the first time the presence of ciguatoxins (CTXs) in sharks. The identification by mass spectrometry of CTXs, including two new analogues, in a bull shark (Carcharhinus leucas) that was consumed by humans, causing the poisoning and death of 11 people in Madagascar in 2013 is described. Typical neurotoxic ciguatera symptoms were recorded in patients, and toxicological assays on extracts of the shark demonstrated CTX-like activity. These results confirm this episode as a ciguatera poisoning event and expand the range of pelagic fish species that are involved in ciguatera in the Indian Ocean. Additionally, gambieric acid D, a molecule originally described in CTX-producing microalgae, was identified for the first time in fish. This finding can contribute to a better understanding of trophic relations within food webs. The present work confirms that consumption of sharks from the Indian Ocean should be considered a ciguatera risk, and actions should be taken to evaluate its magnitude and risk in order to manage shark fisheries.

Recreational Exposure during Algal Bloom in Carrasco Beach, Uruguay: A Liver Failure Case Report

In January 2015, a 20-month-old child and her family took part in recreational activities at Carrasco and Malvín beaches (Montevideo, Uruguay). An intense harmful algae bloom (HAB) was developing along the coast at that time. A few hours after the last recreational exposure episode, the family suffered gastrointestinal symptoms which were self-limited except in the child’s case, who was admitted to hospital in Uruguay with diarrhea, vomiting, fatigue, and jaundice. The patient had increased serum levels of liver enzymes and bilirubin and five days later presented acute liver failure. She was referred to the Italian Hospital in Buenos Aires, being admitted with grade II–III encephalopathy and hepatomegaly and requiring mechanical respiratory assistance. Serology tests for hepatitis A, B, and C, Epstein-Barr virus, and cytomegalovirus were negative. Laboratory features showed anemia, coagulopathy, and increased serum levels of ammonium, alanine aminotransferase (ALT), aspartate aminotransferase (AST), and bilirubin. Autoimmune Hepatitis Type-II (AH-II) was the initial diagnosis based on a liver kidney microsomal type 1 antibodies (LKM-1) positive result, and twenty days later a liver transplant was performed. The liver histopathology had indicated hemorrhagic necrosis in zone 3, and cholestasis and nodular regeneration, which were not characteristic of AH-II. LC/ESI-HRMS (liquid chromatography electrospray ionization high-resolution mass spectrometry) analysis of MCs in the explanted liver revealed the presence of Microsytin-LR (MC-LR) (2.4 ng·gr−1 tissue) and [D-Leu1]MC-LR (75.4 ng·gr−1 tissue), which constitute a toxicological nexus and indicate a preponderant role of microcystins in the development of fulminant hepatitis.