Author Correction: Forearc carbon sink reduces long-term volatile recycling into the mantle.

An Amendment to this paper has been published and can be accessed via a link at the top of the paper.

Author Correction: Forearc carbon sink reduces long-term volatile recycling into the mantle.

Change history: In this Article, the original affiliation 2 was not applicable and has been removed. In addition, in the Acknowledgements there was a statement missing and an error in a name. These errors have been corrected online.

Forearc carbon sink reduces long-term volatile recycling into the mantle.

Carbon and other volatiles in the form of gases, fluids or mineral phases are transported from Earth's surface into the mantle at convergent margins, where the oceanic crust subducts beneath the continental crust. The efficiency of this transfer has profound implications for the nature and scale of geochemical heterogeneities in Earth's deep mantle and shallow crustal reservoirs, as well as Earth's oxidation state. However, the proportions of volatiles released from the forearc and backarc are not well constrained compared to fluxes from the volcanic arc front. Here we use helium and carbon isotope data from deeply sourced springs along two cross-arc transects to show that about 91 per cent of carbon released from the slab and mantle beneath the Costa Rican forearc is sequestered within the crust by calcite deposition. Around an additional three per cent is incorporated into the biomass through microbial chemolithoautotrophy, whereby microbes assimilate inorganic carbon into biomass. We estimate that between 1.2 × 108 and 1.3 × 1010 moles of carbon dioxide per year are released from the slab beneath the forearc, and thus up to about 19 per cent less carbon is being transferred into Earth's deep mantle than previously estimated.

Long-term exposure of Mytilus galloprovincialis to diclofenac, Ibuprofen and Ketoprofen: Insights into bioavailability, biomarkers and transcriptomic changes.

Non-steroidal anti-inflammatory drugs (NSAIDs) represent a growing concern for marine ecosystems due to their ubiquitous occurrence and documented adverse effects on non-target organisms. Despite the remarkable efforts to elucidate bioaccumulation and ecotoxicological potential under short-term conditions, limited and fragmentary information is available for chronic exposures. In this study bioavailability, molecular and cellular effects of diclofenac (DIC), ibuprofen (IBU) and ketoprofen (KET) were investigated in mussels Mytilus galloprovincialis exposed to the realistic environmental concentration of 2.5 µg/L for up to 60 days. Results indicated a significant accumulation of DIC and IBU but without a clear time-dependent trend; on the other hand, KET concentrations were always below the detection limit. Analyses of a large panel of molecular, biochemical and cellular biomarkers highlighted that all investigated NSAIDs caused alterations of immunological parameters, genotoxic effects, modulation of lipid metabolism and changes in cellular turn-over. This study provided the evidence of long-term ecotoxicological potential of NSAIDs, further unraveling the possible hazard for wild marine organisms.

Transcriptional and cellular effects of Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) in experimentally exposed mussels, Mytilus galloprovincialis.

The aim of the present investigation was to provide new insights on accumulation and possible adverse effects of various non-steroidal anti-inflammatory drugs (NSAIDs) in mussels, Mytilus galloprovincialis, exposed to an environmentally realistic concentration (0.5µg/L) of individual compounds, Acetaminophen (AMP), Diclofenac (DIC), Ibuprofen (IBU), Ketoprofen (KET) or Nimesulide (NIM). The measurement of drugs in mussel tissues was integrated with both functional alterations at cellular level and transcriptomic responses. Results indicated the capability of mussels to accumulate DIC and NIM, while AMP, IBU and KET were always below detection limit. A large panel of ecotoxicological biomarkers revealed the early onset of alterations induced by tested NSAIDs on immunological responses, lipid metabolism and DNA integrity. The gene transcription analysis through DNA microarrays, supported cellular biomarker results, with clear modulation of a large number of genes involved in the arachidonic acid and lipid metabolism, immune responses, cell cycle and DNA repair. The overall results indicated an ecotoxicological concern for pharmaceuticals in M. galloprovincialis, with transcriptional responses appearing as sensitive exposure biomarkers at low levels of exposure: such changes, however, are not always paralleled by corresponding functional effects, suggesting caution when interpreting observed effects in terms of perturbed cellular pathways. Fascinating similarities can also be proposed in the mode of action of NSAIDs between bivalves and vertebrate species.

Ecotoxicological potential of non-steroidal anti-inflammatory drugs (NSAIDs) in marine organisms: Bioavailability, biomarkers and natural occurrence in Mytilus galloprovincialis.

Pharmaceuticals represent a major environmental concern since the knowledge on their occurrence, distribution and ecotoxicological potential is still limited particularly in coastal areas. In this study, bioaccumulation and cellular effects of various non steroidal anti-inflammatory drugs (NSAIDs) were investigated in mussels Mytilus galloprovincialis to reveal whether common molecules belonging to the same therapeutic class might cause different effects on non target organisms. Organisms exposed to environmental concentrations of acetaminophen (AMP), diclofenac (DIC), ibuprofen (IBU), ketoprofen (KET) and nimesulide (NIM) revealed a significant accumulation of DIC, IBU and NIM, while AMP and KET were always below detection limit. Nonetheless, for all tested NSAIDs, measurement of a large panel of ecotoxicological biomarkers highlighted impairment of immunological parameters, onset of genotoxicity and modulation of lipid metabolism, oxidative and neurotoxic effects. Laboratory results were integrated with a field study which provided the first evidence on the occurrence of DIC, IBU and NIM in tissues of wild mussels sampled during summer months from an unpolluted, touristic area of Central Adriatic Sea. Overall results demonstrated M. galloprovincialis as a good sentinel species for monitoring presence and ecotoxicological hazard of pharmaceuticals in the Mediterranean.

Arsenic speciation and susceptibility to oxidative stress in the fanworm Sabella spallanzanii (Gmelin) (Annelida, Sabellidae) under naturally acidified conditions: An in situ transplant experiment in a Mediterranean CO2 vent system.

The fanworm Sabella spallanzanii (Gmelin, 1791) (Annelida, Sabellidae) is considered tolerant to several types of stressors but is generally absent from the CO2 vents. A peculiar characteristic of this species is the elevated content of arsenic in the gills, particularly dimethylarsinic acid (DMA), stored as an anti-predatory compound. In this study, modulation of trace metal levels, chemical speciation of arsenic and oxidative stress biomarkers were quantified in S. spallanzanii after a 30days transplant experiment into naturally acidified conditions in a Mediterranean vent system. No significant bioaccumulation of metals was observed in the thoracic tissues and branchial crowns after the translocation period, whereas variations occurred in the relative abundance of different arsenic compounds with the appearance of inorganic forms. The antioxidant system of translocated polychaetes exhibited a significant decrease of enzymatic activities of both catalase and glutathione peroxidases, and the impairment of the overall capability to neutralize hydroxyl radicals (OH). This highlighted an oxidative challenge primarily on the detoxification pathway of hydrogen peroxide. Overall low pH-elevated pCO2 may have detrimental effects on arsenic metabolism and oxidative status of S. spallanzanii, supporting the hypothesis of species-specific differences in vulnerability to ocean acidification.

Cellular responses in the cyprinid Leuciscus cephalus from a contaminated freshwater ecosystem.

The response of wild chubs (Leuciscus cephalus) to chemical pollution was assessed in a metal contaminated river (Cecina River, Italy) through a wide battery of biomarkers which included: Comet assay detecting DNA strand breaks; diffusion assay for apoptosis induction; micronucleus test assessing chromosomal alterations; ethoxyresorufin O-deethylase (EROD) activity for the induction of cytochrome P 4501A; acetylcholinesterase (AChE) activity responsive to pesticide exposure; vitellogenin gene expression in males revealing estrogenic effects. Bioaccumulation of mercury, chromium and polycyclic aromatic hydrocarbons (PAHs) was also determined. Levels of mercury and PAHs were higher in tissues of chubs sampled from the most downstream station, reflecting an anthropogenic pollution of industrial origin. Otherwise, accumulation of Cr was quite similar in fish along the entire course of Cecina River confirming a natural origin due to local geochemical features. Biomarker responses revealed a significant increase of apoptotic cells, DNA stand breaks and micronucleus frequency in chubs from the more impacted sites. A slight EROD induction and AChE inhibition were only seen at the most downstream station demonstrating a limited impact due to PAHs and pesticides. On the other hand, the induction of vitellogenin gene in male chubs was measured in all the sites, suggesting a diffuse estrogenic effect. This study confirmed the utility of large batteries of biomarkers in biomonitoring studies and the suitability of wild chub as bioindicator organism for river basins.

Trace metal concentrations and susceptibility to oxidative stress in the polychaete Sabella spallanzanii (Gmelin) (Sabellidae): potential role of antioxidants in revealing stressful environmental conditions in the Mediterranean.

The polychaete Sabella spallanzanii (Gmelin) (Sabellidae) is a widely distributed species throughout the Mediterranean where it is commonly found in sheltered shallow areas and up to 30 m depth in more exposed waters. The sedentary habit, the filter-feeding behavior and its capability to colonize disturbed environments such as harbors, suggest the potential utility of this organism as a bioindicator in environmental monitoring programs. The aim of this work was a preliminary characterization of S. spallanzanii, integrating chemical data on trace metal concentrations with the biochemical analysis of antioxidant defenses which play an important role in mediating responses and adaptation to stressful environmental conditions. Organisms were collected in four locations of the Adriatic and Tyrrhenian Sea, characterized by a moderate impact or influenced by organic enrichment or sulphuric emissions. Trace metal concentrations (Cd, Cr, Cu, Fe, Mn, Ni, Pb, Zn) were comparable to those of other invertebrate species and quite typical for unpolluted environments. Analyses of individual antioxidants (superoxide dismutase, catalase, glutathione peroxidases, glutathione S-transferases, glutathione reductase) were integrated with measurement of the total oxyradical scavenging capacity toward specific forms of ROS; the TOSC assay, quantifying the overall capability of a tissue to neutralize specific reactive oxygen species provide a more integrated picture of the balance between prooxidant factors and antioxidant defenses, with important indications about the role of different ROS in appearance of oxidative disease. The antioxidant profile was influenced by the different physiological functions of the analyzed tissues, namely the branchial crown, involved in filtration of large volumes of seawater, and the thorax where digestive processes occur. The analysis of antioxidant defenses revealed significant variations in polychaetes from various sampling sites suggesting the influence of specific environmental conditions like those limiting oxygen availability. Our results confirm the role of antioxidants in adaptation to stressful environmental conditions and their importance in ecotoxicological studies for the sensitivity in revealing the occurrence of biological disturbance.

In vitro antioxidant activities of mouthrinses and their components.

OBJECTIVES: Several forms of periodontal diseases (PD) are often associated with activated phagocytosing leukocytes and contemporary free radical production. Host antioxidant defenses could benefit from mouthrinses used as adjuncts to counteract plaque-associated bacteria. The aim of the present study was to determine possible antioxidant activity (AA) of a number of antiseptic mouthrinses and of their stated active principles (AP), regardless of their efficacy as antimicrobial agents. MATERIAL AND METHODS: The antioxidant activities of 11 mouthrinses and their active principles were tested with a specific spectrophotometric method. Comet assay was used to test whether pure chemical antioxidant activity actually corresponded to prevention of in vitro DNA fragmentation. RESULTS: Methylsalicylate-containing mouthrinses were the most effective. Several compounds, and some vehicles, behaved as antioxidants. Fibroblast DNA fragmentation was limited by preincubation with methylsalicylate-containing mouthrinse but was unaffected by treatment with chlorexidine. CONCLUSION: The results described herein indicate that several mouthrinses possess AA; such a property could be ascribed to either AP or vehicles or both. All the data were obtained in systems in vitro and the demonstration of in vivo AA is necessary. These findings could be useful in the treatment of some forms of PD and should be considered when arranging new mouthrinse formulations.