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In this article, we document a strategy for addressing the difficulties of analyzing complex chemical mixtures of endocrine-disrupting substances (EDSs) in surface waters. The overall approach includes effect-based assessments to detect mixtures of EDSs exerting real-world effects, the use of passive samplers for in situ extraction and preconcentration of compounds, effect-directed analysis to isolate causative substances and finally, nontargeted analysis to facilitate their identification. This package of integrated approaches can be instrumental to address endocrine-disrupting mixtures in water bodies because it balances chemical- and effect-based methods that are inclusive of the broad diversity of chemicals functioning as EDSs. These methods are complementary to each other and, when used together, result in a synergistic and multidisciplinary approach to holistically detect and manage complex mixtures of EDSs exerting a myriad of effects in aquatic ecosystems.

Fish aggregating devices (FADs) are floating objects typically used to attract and capture pelagic fish in industrial tuna fisheries. This study documents 9 cases, involving 31 marine mammals, of incidentally captured, killed or otherwise retrieved cetaceans and pinnipeds which were used, or presumably used, as bait for improvised fish aggregation devices (IFAD) by artisanal fishers in coastal Ecuador. At least 3 species of small cetaceans were affected, including pantropical spotted dolphin Stenella attenuata, short-finned pilot whale Globicephala macrorhynchus, pygmy killer whale Feresa attenuata and an unidentified small delphinid, as well as South American sea lions Otaria byronia which were reportedly killed on purpose for this fishing practice. A sperm whale Physeter macrocephalus and a humpback whale Megaptera novaeangliae were presumably found floating at sea and opportunistically exploited as FADs. The South American sea lion represented 80.6% of marine mammals used as bait associated with FADs (25 sea lions out of 31 marine mammals), while the remaining 5 (possibly 6) cetacean species represented 19.4%. This is the first report of baited FADs in Ecuador, the extent of which is still unknown. This fishing technique has not been documented in other nations along the west coast of South America, although baiting of gillnets with marine mammal parts is common in Peru. Without fisheries management and regulation, this illegal fishing practice could rapidly expand and lead to further direct kills and conservation problems for targeted marine mammal populations in the eastern tropical Pacific. A bottom-up fisheries policy in concert with community-based conservation to ban the use of marine mammals as FAD bait is recommended.

The terms organic micropollutants or emerging contaminants are used to refer to unregulated organic trace pollutants that are frequently detected in environmental matrices, especially surface waters (Magi et al., 2018). These compounds include pharmaceuticals and personal care products (PPCPs), pesticides and surfactants. They are released to aquatic environments mainly through effluent from wastewater treatment plants (WWTPs) (Chen et al., 2016; Yang et al., 2017). Although the pollutant concentrations often occur at trace or ultra-trace levels (ng L−1 or pg L−1), their presence is considered a potential risk to the environment and human health. Thus, monitoring programs are essential to determine their concentrations and consequent ecotoxicological risk in the environment (Fedorova et al., 2014; Ibrahim et al., 2013; Magi et al., 2018).

A semi-automated and sensitive method was developed for simultaneous determination of the six most consumed artificial sweeteners (AS) in surface waters using thin-film solid-phase microextraction (TF-SPME) and high-performance liquid chromatography (HPLC). A triple quadrupole mass spectrometer and an electrospray ionization source (ESI-MS) run in negative ionization and multiple reaction monitoring modes were employed for instrumental analysis. The TF-SPME method was optimized for the extraction phase, sample pH, desorption solvent, extraction time, and desorption time. In-house-synthetized-hydrophilic-lipophilic balance weak anion exchange (HLB-WAX) particles imbedded within a polyacrylonitrile (PAN) binder were selected as the extraction phase for the thin-film coating due to their cost-effectiveness and enhanced sensitivity for artificial sweeteners. Suitable analytical parameters that include linearity (R2 > 0.9914), recovery > 80%, inter, and intra-reproducibility less than 18% were obtained for the AS compounds studied. The developed method estimated limits of detection (LODs) ranging from 0.004 to 0.038 ng mL−1 The SPME method was successfully applied for the determination of ultra-trace levels of AS in water samples collected from Grand River (Ontario, Canada), downstream of three municipal wastewater treatment plants (WWTPs). Concentrations ranging from 0.03 to 20.3 ng mL−1 were found for the AS compounds studied.

An adult olive ridley turtle Lepidochelys olivacea with lesions suggestive of fibropapillomatosis was rescued on the coast of San Antonio, central Chile. Histopathologic analysis showed an exophytic and pedunculated mass formed by epidermal papillary projections supported by fibrovascular cores, epidermal hyperplasia and marked orthokeratotic hyperkeratosis. ChHV5 unique long genes UL27, UL28 and UL30 were amplified from tumor lesions and sequenced for phylogeny. Phylogenetic reconstruction showed the Chilean sequences clustering with the Eastern Pacific group. This is the first case of fibropapillomatosis in an olive ridley turtle diagnosed in Chile and in the southeastern Pacific region. Our results suggest a regional grouping of ChHV5 variants independent of the marine turtle's species.

A novel strategy for the analysis of 20 organochlorine pesticides (OCPs) monitoring in marine surface waters through ethylenevinyl acetate (EVA) passive samplers was developed and validated. The approach is based on the coupled of ultrasound-assisted solvent extraction (UASE) and headspace solid-phase microextraction (HS-SPME) as extraction method for OCPs from EVA samplers. The UASE-HS-SPME method was optimized with a 27-4 Plackett-Burman design, while the significant factors (salting out, temperature and extraction time) were optimized using a central composite design (CCD) combined with desirability function (DF). The OCPs detection was performed using multiple reaction monitoring (MRM) by gas chromatography-tandem mass spectrometry (GC-MS/MS). The optimum experimental conditions comprised: salting out: 23% wv-1 NaCl, temperature: 75°C and extraction time: 55 min. The optimized method was validated in terms of linearity (R20.9946), recovery (61%) and inter-day and intra-day reproducibility (19%) for 20 OCPs studied. The limits of detection (LODs) were ranging from 0.01 ng for α-hexachlorocyclohexane and 0.27 ng for endrin aldehyde. Finally, the methodology was tested in marine surface seawater of Southern Chile using EVA samplers, where twelve OCPs were detected at ultra-trace levels (ngL

Fibropapillomatosis is a neoplastic disease that afflicts sea turtles. Although it is disseminated worldwide, cases of the disease have not been reported in the southeastern Pacific region. We describe a case of fibropapillomatosis in a green sea turtle ( Chelonia mydas) during its rehabilitation at the Machalilla National Park Rehabilitation Center, Ecuador. Viral presence was confirmed by PCR, targeting fragments of the chelonid alphaherpesvirus 5 (ChHV5) unique long (UL) genes, UL27, UL28, and UL30. The amplicons were sequenced and included in a global phylogenetic analysis of the virus with other reported sequences from GenBank. Results showed that the available viral sequences segregated into five phylogeographic groups: western Atlantic and eastern Caribbean, central Pacific, western Pacific, Atlantic, and eastern Pacific groups. The concatenated ChHV5 sequences from Ecuador clustered with the eastern Pacific sequences.

Uno de los problemas fundamentales en el diseño de una estrategia de producción/operaciones se centra en la definición y jerarquización de las prioridades competitivas, que deben orientar las acciones estratégicas para el mejoramiento del sistema productivo. Por tal razón, el presente artículo expone un procedimiento basado en técnicas multicriterio y métodos de expertos, que sirve como herramienta para establecer el conjunto de tareas de fabricación y para apoyar el proceso de construcción de la estrategia de producción.