Silver-titanium polymeric nanocomposite non ecotoxic with bactericide activity.

In view of the intense interest in applications of silver nanoparticles in products for the medical field and in food preservation packaging due to their antimicrobial properties, the ecotoxicology of silver nanocomposites was evaluated in films. Test with the sea urchin Echinometra lucunter, to evaluate embryonic development and contamination by the action of silver and titanium nanoparticles in polyethylene nanocomposite films presents new results. The silver nanoparticle's stability in polymeric materials can be enhanced by adding carriers, such as titanium dioxide and montmorillonite clay (MMT) without to producing one unfriendly material. For this research, low-density polyethylene (LDPE)/linear low-density polyethylene (LLDPE) were used processed in a twin-screw extruder, followed by gamma irradiation with 25 kGy and characterized by ecotoxicology assays, field emission scanning electron microscopy (FESEM), scanning electron microscopy and energy dispersive spectroscopy (SEM-EDX), differential scanning calorimetry (DSC), thermogravimetric analysis (TG), Raman spectroscopy (SERS) and mechanical properties. The antibacterial properties of the LDPE films were investigated against Escherichia coli and Staphylococcus aureus. The gamma irradiation had an important effect in the synthesis of silver nanoparticles resulting in bactericidal activity and the death of 100% of the tested bacteria. The evaluation of the environment was considered with the ecotoxicological investigation carried out. The results indicated that the polymeric films with silver nanoparticles and TiO2 do not contaminate the environment and neither interfere with the larval development of Echinometra lucunter. The obtained materials can be used in various applications with antimicrobial properties.

Microscale Toxicity Identification Evaluation (TIE) for interstitial water of estuarine sediments affected by multiple sources of pollution.

Estuaries in the world are affected by different contamination sources related to urbanisation and port/industrial activities. Identifying the substances responsible for the environmental toxicity in estuaries is challenging due to the multitude of stressors, both natural and anthropogenic. The Toxicity Identification and Evaluation (TIE) is a suitable way of determining causes of toxicity of sediments, but it poses difficulties since its application is labour intensive and time consuming. The aim of this study is to evaluate the diagnosis provided by a TIE based on microscale embryotoxicity tests with interstitial water (IW) to identify toxicants in estuarine sediments affected by multiple stressors. TIE showed toxicity due to different combinations of metals, apolar organic compounds, ammonia and sulphides, depending on the contamination source closest to the sampling station. The microscale TIE was able to discern different toxicants on sites subject to different contamination sources. There is good agreement between the results indicated in the TIE and the chemical analyses in whole sediment, although there are some disagreements, either due to the sensitivity of the test used, or due to the particularities of the use of interstitial water to assess the sediment toxicity. The improvement of TIE methods focused on identifying toxicants in multiple-stressed estuarine areas are crucial to discern contamination sources and subsidise management strategies.

Sub-lethal combined effects of illicit drug and decreased pH on marine mussels: A short-time exposure to crack cocaine in CO2 enrichment scenarios.

The increasing CO2-concentrations in the atmosphere promote ocean acidification. Seawater chemistry changes interact with contaminants, such as illicit drugs in the coastal zones. This work evaluates impacts of pH decrease and crack-cocaine exposure on the commercial mussel Perna perna through biomarker responses (lysosomal membrane stability, lipid peroxidation, and DNA strand breaks). The organisms were exposed to different crack-cocaine concentrations (0.5, 5.0, and 50 µg L-1) combined with different pH values (8.3, 8.0, 7.5, 7.0, 6.5, and 6.0) for 96 h. Crack-cocaine in the different acidification scenarios triggered cyto-genotoxicity, which affected the overall health of mussels exposed to cocaine environmentally relevant concentration. This study produced the first data on biomarker responses associated with CO2-induced acidification and illicit drugs (crack-cocaine) in marine organisms.

Mussels get higher: A study on the occurrence of cocaine and benzoylecgonine in seawater, sediment and mussels from a subtropical ecosystem (Santos Bay, Brazil).

Data on the occurrence of cocaine (COC) and benzoylecgonine (BE) in marine environmental compartments are still limited, with few studies reporting superficial water contamination, mainly in tropical zones. In this sense, environmental data of these substances are essential to identify potential polluting sources, as well as their impact in costal ecosystems. The aim of this study was to evaluate the occurrence of COC and BE in seawater, sediment and mussels from a subtropical coastal zone (Santos Bay, São Paulo, Brazil), as well as to determine a field measured Bioaccumulation Factor (BAF). COC and BE were detected in all water samples in concentrations ranging from 1.91 ng·L-1 to 12.52 ng·L-1 and 9.88 ng·L-1 to 28.53 ng·L-1, respectively. In sediments, only COC was quantified in concentrations ranging from 0.94 ng·g-1 to 46.85 ng·g-1. Similarly, only COC was detected in tissues of mussels 0.914 µg·kg-1 to 4.58 µg·kg-1 (ww). The field-measured BAF ranged from 163 to 1454 (L·kg-1). Our results pointed out a widespread contamination by cocaine and its main human metabolite benzoylecgonine in Santos Bay. Mussels were able to accumulate COC in areas used by residents and tourists for bathing, fishing, and harvest, denoting concern to human health. Therefore, our data can be considered a preliminary assessment, which indicates the need to evaluate drugs (including illicit as COC) in environmental and seafood monitoring programs, in order to understand their risks on the ecosystem and human health.

Estrogen levels in surface sediments from a multi-impacted Brazilian estuarine system.

Estrogen levels were assessed in surface sediments from one of the most industrialized and urbanized estuarine systems in Latin America (SSES, Santos and São Vicente estuarine system). Estriol (E3) presented quantifiable levels in all sampled sites, ranging from 20.9 ng g-1 to 694.2 ng g-1. 17ß-estradiol (E2) and 17α-ethinylestradiol (EE2) were also detected in almost all sampled sites. The highest concentration of E2 was 23.9 ng g-1, whereas high levels of EE2 86.3 ng g-1. The occurrence of estrogens in SSES was diffuse and partially related to a domestic sewage outfall. Estrogens were also found in areas with substantial contribution of sanitary effluents from domiciles not covered by sanitation services. Our results reinforce that studies on environmental contamination by estrogens should not be spatially limited to the vicinities of point sources. These results contribute to raise awareness on the need of a formal approach to assess ecological risks of estrogens in the SSES.

Harmful effects of cocaine byproduct in the reproduction of sea urchin in different ocean acidification scenarios.

This study has as main objective assessing the toxicity of crack-cocaine combined with different scenarios of ocean acidification on fertilization rate and embryo-larval development of Echinometra lucunter sea urchin. Effects on early life stages were assessed at five different concentrations (6,25 mg.L-1; 12,5 mg.L-1; 25 mg.L-1; 50 mg.L-1 and 100 mg.L-1) of crack-cocaine at four different pH values (8.5; 8.0; 7.5; 7.0). The pH values were achieved using two different methodologies: adding hydrochloric acid (HCl) and injecting carbon dioxide (CO2). The fertilization test did not show significant differences (p ≤ 0.05) compared with control sample at pH values 8.5; 8.0 and 7.5. Results of embryo-larval assays showed a half maximal effective concentration (EC50) of crack-cocaine at pH values tested (8.5, 8.0, 7.5) as 58.83, 10.67 and 11.58 mg/L-1 for HCl acidification and 58.83, 23.28 and 12.57 mg/L-1 for CO2 enrichment. At pH 7.0 the effects observed in fertilization rate and embryo development were associated with the acidification. This study is the first ecotoxicological assessment of illicit drug toxicity in aquatic ecosystems at different ocean acidification scenarios.

Seasonal monitoring of cocaine and benzoylecgonine in a subtropical coastal zone (Santos Bay, Brazil).

Illicit drugs and their metabolites represent a new class of emerging contaminants. These substances are continuously discharged into wastewater which have been detected in the aquatic environment in concentrations ranging from ng.L-1 to µg.L-1. Our study detected the occurrence of cocaine (COC) and benzoylecgonine (BE) in a subtropical coastal zone (Santos Bay, SP, Brazil) within one year. Water samples (surface and bottom) were collected from the Santos Submarine Sewage Outfall (SSOS) area. COC and BE were measured in the samples using ultra-performance liquid chromatography coupled to tandem mass spectrometry (UPLC-ESI-MS/MS). Concentrations ranged from 12.18 to 203.6 ng.L-1 (COC) and 8.20 to 38.59 ng.L-1 (BE). Higher concentrations of COC were observed during the end of spring, following the population increase at summer season. COC and its metabolite occurrence in this coastal zone represent a threat to coastal organisms.

Marine contamination and cytogenotoxic effects of fluoxetine in the tropical brown mussel Perna perna.

Concerns are growing about the presence of fluoxetine (FLX) in environmental matrices, as well as its harmful effects on non-target organisms. FLX in aquatic ecosystems has been detected in a range varying from pg/L to ng/L, while adverse effects have been reported in several organisms inhabiting freshwater and marine environments. The present study quantifies FLX concentrations in seawater samples from Santos Bay, Brazil and assesses metabolic responses and sublethal effects on the tropical brown mussel Perna perna. Levels of ethoxyresorufin­O­deethylase, dibenzylfluorescein dealkylase, glutathione S-transferase, glutathione peroxidase, cholinesterase, lipoperoxidation, and DNA damage were assessed in the gills and digestive gland of these animals, and lysosomal membrane stability was also assessed in hemocytes. FLX altered phase I and II enzyme activities, caused cytogenotoxic effects, and negatively impacted the overall health of mussels exposed to environmentally relevant concentrations. These findings contribute to characterize the risks of introducing this drug into the marine environment.

Ecotoxicological effects of losartan on the brown mussel Perna perna and its occurrence in seawater from Santos Bay (Brazil).

The antihypertensive losartan (LOS) has been detected in wastewater and environmental matrices, however further studies focused on assessing the ecotoxicological effects on aquatic ecosystems are necessary. Considering the intensive use of this pharmaceutical and its discharges into coastal zones, our study aimed to determine the environmental concentrations of LOS in seawater, as well as to assess the biological effects of LOS on the marine bivalve Perna perna. For this purpose, fertilization rate and embryolarval development were evaluated through standardized assays. Phase I (ethoxyresorufin O­deethylase EROD and dibenzylfluorescein dealkylase DBF) and II (glutathione S-transferase GST) enzymes, glutathione peroxidase (GPx), Cholinesterase (ChE), lipoperoxidation (LPO) and DNA damage were used to analyze sublethal responses in gills and digestive gland of adult individuals. Lysosomal membrane stability was also assessed in hemocytes. Our results showed the occurrence of LOS in 100% of the analyzed water samples located in Santos Bay, Sao Paulo, Brazil, in a range of 0.2 ng/L-8.7 ng/L. Effects on reproductive endpoints were observed after short-term exposure to concentrations up to 75 mg/L. Biomarker responses demonstrated the induction of CYP450 like activity and GST in mussel gills exposed to 300 and 3000 ng/L of LOS, respectively. GPx activity was also increased in concentration of exposure to 3000 ng/L of LOS. Cyto-genotoxic effects were found in gills and hemocytes exposed in concentrations up to 300 ng/L. These results highlighted the concern of introducing this class of contaminants into marine environments, and pointed out the need to include antihypertensive compounds in environmental monitoring programs.

Sediment toxicity identification evaluation (TIE phases I and II) based on microscale bioassays for diagnosing causes of toxicity in coastal areas affected by domestic sewage.

Domestic sewage is a major problem in highly urbanized coastal areas worldwide. In the present study, toxicity identification evaluation (TIE) phases I and II were applied to sediment interstitial water from 2 locations along the São Paulo coast in southeastern Brazil: the sewage outfalls from the city of Santos, a densely urbanized area, and the city of Bertioga, a less urbanized area. An adapted microscale sea urchin embryo-larval development bioassay was employed. Phase TIE-I manipulations were 1) ethylenediamine tetraacetic acid (EDTA) addition, 2) aeration at modified pH, 3) C18 solid-phase extraction (SPE), and 4) addition of Na2 S2 O3 . The results of the Santos TIE-I indicated toxicity by sulfides and substances with affinity to C18 resin. In Bertioga, toxicity was the result of NH3 , metals, and arsenic, as well as substances with affinity to C18 resin. Phase TIE-II aimed to specify the causes of toxicity by testing the toxicity of eluates of the sublation and C18 SPE manipulation. The results reinforced the role of both surfactants and nonpolar compounds as causative agents of toxicity in both Santos and Bertioga. Chemical analyses of sediment interstitial water or whole sediment ruled out the influence of polycyclic aromatic hydrocarbons (PAHs) or polychlorinated biphenyls (PCBs) in the toxicity of both sampling sites. Other hydrophobic substances may play a role in the toxicity of Santos and Bertioga effluents. Efforts to remove such substances from sanitary effluents must be prioritized. Environ Toxicol Chem 2017;36:1820-1832. © 2017 SETAC.

Análise da qualidade sanitária da areia das praias de Santos, litoral do estado de São Paulo / Analysis of sand quality health in Santos beach, coast of São Paulo state

RESUMO: Em Santos, litoral de São Paulo, a avaliação da qualidade microbiológica da água das praias é realizada pela prefeitura e pela Companhia Ambiental do Estado de São Paulo (CETESB). Entretanto, a mesma atenção não é direcionada à areia das praias. A areia representa um potencial vetor de contaminação e pode constituir reservatório de microrganismos patogênicos. O objetivo deste estudo foi avaliar a qualidade microbiológica da areia das praias de Santos, São Paulo. Utilizou-se a técnica das membranas filtrantes para os grupos de coliformes fecais (Escherichia coli ) e enterococos. As amostras foram coletadas em sete pontos das praias de Santos. Os ensaios foram realizados mensalmente durante 8 meses e os resultados, expressos em unidades formadoras de colônias (UFC) de bactérias por 100 g de areia, variaram de 40.000 a 2.700.000 para E. coli e de não detectado a 95.000 para enterococos, encontrando-se acima dos valores orientadores existentes em âmbito nacional (3.800 UFC.100g-1 - Rio de Janeiro) e internacional (100.000 UFC.100g-1 - Portugal). O contato com areia contaminada pode causar diversas doenças, comprometendo a qualidade de vida da população. Torna-se importante a realização de estudos baseados em evidências epidemiológicas de exposição e análises de risco, para se estabelecer padrões de qualidade e políticas públicas para monitoramento e gerenciamento da qualidade sanitária da areia das praias do litoral de São Paulo.

ABSTRACT: In Santos, coast of São Paulo State, the evaluation of the microbiological quality of the beach water is performed weekly by the Companhia Ambiental do Estado de São Paulo (CETESB), the environmental agency of the São Paulo state government. However, the same attention is not given to the sand of the beaches. Sand represents a potential contamination vector and may constitute a reservoir of pathogenic microorganisms. This study aimed to evaluate the microbiological quality of sands from Santos beaches throughout the quantification of bacteria colonies from the groups of fecal coliforms (Escherichia coli ) and Enterococcus, using the membrane filter technique. The analyses were executed monthly during 8 months and the results, expressed in bacteria colony forming units (CFU) per 100 grams of sand, vary from 40,000 to 2,700,000 for E. coli and from not detected to 95,000 for Enterococcus, being above the currently guideline values in national (3,800 CFU.100g-1) and international (100,000 CFU.100g-1) levels. It's important to mention that these guideline values were based on results from microbiological analyses of sands collected from beaches that are distant from large urban areas. The contact with contaminated sand may cause diseases, provoking impacts on the population's life quality. There is a need for further studies based on epidemiological evidences of exposure and risk analysis, in order to establish quality standards and public policies aimed to monitoring and managing the sanitary quality of sands from São Paulo's coast beaches.