The combined use of chemical and biochemical markers in Rutilus rutilus to assess the effect of dredging in the lower course of the Ebro River.

The lower course of the Ebro River is polluted with high concentrations of organochlorine compounds dumped by a chloro-alkali plant during the last century. A remediation plan, including building of a protective wall, removal and disposal of polluted sediments started in 2012. With the aim of assessing the effects of dredging of contaminated sediments and potential alterations of water quality, areas located upstream (RR) and downstream (BE, A) the chemical plant (FL) were monitored prior (October 2012) and during dredging (June 2013) using roach (Rutilus rutilus) as sentinel organisms. Concentrations of organochlorine compounds (OCs) in fish muscle and biliary levels of polycyclic aromatic hydrocarbons (PAHs), galaxolide (HHCB) and alkyphenols (APEs) were determined together with selected enzymatic activities (7-ethoxyresorufin-O-deethylase (EROD), 7-benzyloxy-4-trifluoromethyl-coumarin O-debenzyloxylase (BFCOD) and UDP-glucuronyltransferase (UGT)) in the liver. The obtained results proved the effectiveness of the wall retaining suspended particles and avoiding further contamination of downstream sites as fish sampled at downstream sites showed up to 9-fold higher concentrations of OCs in muscle during wall construction than during dredging. EROD and UGT activities were induced in fish from downstream sites; however, no clear response to the observed pollution gradient was detected.

PAHs in Water, Sediment and Biota in an Area with Port Activities.

The study reports concentration of 16 PAHs in sediment, water, plankton and in muscle and liver of sampled fishes from Paranagua Bay in Southern Brazil. According to the range of PAHs concentration found in sediments (ΣPAHs 15.33-133.61 µg g-1) and water (ΣPAHs 51.20-162.37 µg L-1), the area was characterized as slightly polluted. In contrast, significant concentration of PAHs was found in fish and plankton, ranging from 26.52 to 2055.00 µg g-1 and 175.41 to 2096.10 µg g-1, respectively. The concentrations were 15 times more than in sediments. Even though the concentration of PAHs in water and sediments are low, the concentration in fish tissues are alarmingly. The hypothesis of bioaccumulation is not discharged. Accumulation levels of PAHs in the biota were used to calculate biota-sediment accumulation factor (BSAF) and bioaccumulation factor (BAF). For example, fish sampled from site 11 had a BAF of 49 and BSAF of 2.3, whereas for plankton the BAF was 16.3 and BSAF 0.7. Mean values of BAF and BSAF were higher in plankton samples. It is known that PAHs are enzymatically metabolized by organisms, thus the lower BSAF in fish might have resulted from biochemical transformation. Statistical analysis indicates no significant correlation between total PAHs concentration in fish tissues and total lipid content in fishes (p > 0.1).Accumulation in tissues is controlled by lipid content, although factors, such as spatial distribution of compounds, trophic level, and behavior of each species in the environment, must be considered. Besides, size and nutritional conditions can affect both absorption as well as metabolic process and excretion. A positive and significant correlation was found between total PAHs and trophic positions obtained from FishBase data (r2 = 0.784; p < 0.05). Thus, it seems that the area, with great influence of urban and industrial activities, and the bioaccumulation compounds, such as PAHs, depend on others factors, as well as resuspension of sediments and releasing of compounds for biota.

Chemical structure and biological activity of the (1 → 3)-linked ß-D-glucan isolated from marine diatom Conticribra weissflogii.

Several polysaccharides are considered to be "biological response modifiers" (BRM) - these refer to biomolecules that augment immune responses and can be derived from a variety of sources. Microalgae produce a diverse range of polysaccharides and could be an excellent source of BRM. Here, we describe the chemical structure and biological activity of water-soluble polysaccharide isolated from the marine diatom Conticribra weissflogii. Using chemical and NMR spectroscopic methods, the polysaccharide was identified as a (1 â†’ 3)-linked ß-D-glucan with a low proportion of C-6 substitution by single ß-glucose units. The biological activity of this low molecular weight ß-glucan (11.7 kDa) was investigated with respect to glioblastoma cell lines (U87 MG and U251) and macrophages (RAW 264.7). We observed that this ß-D-glucan did not exhibit cytotoxic activity against glioblastoma cells, but did enhance the phagocytic activity of macrophages, suggesting that it possesses immunomodulatory properties.

Assessing the impact of waste water effluents on native fish species from a semi-arid region, NE Spain.

Mediterranean rivers are strongly affected by pollution and water scarcity. Over the summer period, urban and industrial effluents arrive into the rivers with little dilution. In order to assess the water quality, two native fish species, Barbus meridionalis and Squalius laietanus, were collected from six sites along the Ripoll River (Spain). PAH metabolites, alkylphenols (nonylphenol and octylphenol) and the musk galaxolide levels were determined in bile. 7-Ethoxyresorufin-O-deethylase (EROD) and 7-benzyloxy-4-trifluoromethyl-coumarin O-debenzyloxylase (BFCOD) were measured as metabolic biomarkers, and the activity of CYP19 aromatase was determined in the ovaries of B. meridionalis as a biomarker of endocrine disruption. The analysis of bile indicated that fish from the lower course of the river were highly exposed to different pollutants. Accordingly, a significant induction of EROD (9 to 10-fold) and BFCOD (3 to 5-fold) activities were detected in both fish species together with an increased aromatase activity in females of B. meridionalis from the most polluted sites. Considering that sewage treatment plant (STP) effluents are essential for maintaining environmental flows in small Mediterranean rivers, this study highlights the need to improve the efficiency of STPs to protect fish health.

Tracking capybara (Hydrochoerus hydrochaeris) feces contribution method in aquatic environments using sterols.

The monitoring of fecal contamination (human and animal) is an incessant challenge. In this approach, microbiological methods play an important role, though with substantial limitations. Organic compounds, such as sterols, are often used to trace fecal contamination. Although the fecal sterols profiles of some animals are already known, capybara, a typical mammal from South America, is a significant contributor to aquatic fecal contamination because of its water dependence; and still there is no one way, scientifically speaking, to trace its fecal contribution. The aim of the present study was to provide a tool to measure the temporal fecal contribution of capybara in aquatic systems. We examined the sterol content of capybara feces and compared with another species (sheep, cow, horse, pig, hen, duck, cat, dog, opossum, and human). From numerical relationships among fecal sterols, 6 ratios were delineated and tested to assess their potential to identify the capybara feces contribution in contaminated environments. Statistical analysis showed that 3 ratios were able to differentiate capybara feces from other sources. Such ratios were applied in samples of a sediment core from an urban area in south Brazil with a large capybara population. The temporal trend showed a significant contribution of capybara feces in the last 100 yr. Environ Toxicol Chem 2018;37:353-361. © 2017 SETAC.

Polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in sediments from an urban- and industrial-impacted subtropical estuary (Babitonga Bay, Brazil).

Babitonga Bay is a large estuary, which has been under pressure from anthropogenic activities coexisting with a natural area of Atlantic rainforest and mangrove systems. The concentration of persistent organic pollutants (POPs), such as polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) was determined to evaluate the contamination status and the determine possible pollution sources in the estuary. The ∑DDT (sum of DDT, DDE and DDD concentrations) was the predominant OCP group, with concentrations ranging from

Characterization of quality of sediments from Paranaguá Bay (Brazil) by combined in vitro bioassays and chemical analyses.

The present study characterizes the quality of sediments from the Paranaguá Estuarine Complex (South Brazil). Polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs), and organochlorine pesticides (OCPs) were determined in sediment samples together with a series of different in vitro bioassays. The fish hepatoma cell line (PLHC-1) was used to determine the presence of cytotoxic compounds and CYP1A- and oxidative stress-inducing agents in sediment extracts. Ovarian microsomal fractions from sea bass (Dicentrarchus labrax) were used to detect the presence of endocrine disrupters that interfered with the synthesis of estrogens (ovarian CYP19). Despite the relatively low levels of pollutants and no evidence of negative effects based on guideline levels, sediments collected close to harbors were enriched with CYP1A-inducing agents and they showed higher cytotoxicity. In contrast, sediments from internal areas inhibited CYP19 activity, which suggests the presence of endocrine disrupters at these sites. Overall, the selected bioassays and the chemistry data led to the identification of potentially impacted areas along the Paranaguá Estuarine Complex that would require further action to improve their environmental quality. Environ Toxicol Chem 2017;36:1811-1819. © 2016 SETAC.

Assessment of the environmental quality of coastal sediments by using a combination of in vitro bioassays.

The environmental quality of marine sediments collected in the area of influence of the Po and Danube Rivers was assessed by using a battery of bioassays based on the use of PLHC-1 cells, zebrafish-Pxr-transfected COS-7 cells, and sea bass ovarian subcellular fractions. This allowed the determination of multiple endpoints, namely, cytotoxicity, oxidative stress, induction of CYP1A, activation of zebrafish Pxr and inhibition of ovarian aromatase. Organic extracts of sediments influenced by the Danube River and collected near harbors and urban discharges showed significant cytotoxicity, CYP1A induction and inhibition of aromatase activity. An analogous response of CYP1A induction and zfPxr activation was observed, which suggests the existence of common ligands of AhR and PXR in the sediment extracts. The study highlights the usefulness of the selected bioassays to identify those sediments that could pose a risk to aquatic organisms and that require further action in order to improve their environmental quality.