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Consequences of combined exposure to thermal stress and the plasticiser DEHP in Mytilus spp. differ by sex
2021
Mincarelli, Luana Fiorella | Rotchell, Jeanette M. | Chapman, Emma C. | Turner, Alexander P. | Wollenberg Valero, Katharina C.
Little is known about the combined effect of environmental factors and contaminants on commercially important marine species, and whether this effect differs by sex. In this study, blue mussels were exposed for seven days to both single and combined stressors (i.e., +3 °C elevated temperature and two environmentally relevant concentrations of the plastic softener DEHP, 0.5 and 50 μg/l) in a factorial design. Males were observed to be more sensitive to high temperature, demonstrated by the significant increase in out-of-season spawning gonads and higher gene expression of the antioxidant catalase and the estrogen receptor genes. On the other hand, while the gametogenesis cycle in females was more resilient than in males, DEHP exposure altered the estrogen-related receptor gene expression.We show that the combined stressors DEHP and increased temperature, in environmentally relevant magnitudes, have different consequences in male and female mussels, with the potential to impact the timing and breeding season success in Mytilus spp.
Mostrar más [+] Menos [-]Worldwide actions against plastic pollution from microbeads and microplastics in cosmetics focusing on European policies. Has the issue been handled effectively?
2021
Anagnosti, Lamprini | Varvaresou, Athanasia | Pavlou, Panagoula | Protopapa, Evangelia | Carayanni, Vilelmine
Microbeads are solid primary microplastics < 5 mm in diameter that are added to cosmetic products for cleansing and/or exfoliation of the skin. After use, they are discharged into the drain and end up in Wastewater Treatment Plants (WWTPs), from which they can escape into waters. Once disposed, there is no efficient method of recovery and the environmental conditions do not allow full biodegradation. Focusing mainly on the possible effect of microbeads on the environment and the human health, and taking into account that there have always been alternatives with similar cost, scientists suggested banning microbeads from cosmetic products. Despite the increasing knowledge on the microplastics' effects, the pressure from non-governmental organizations (NGO's) and the increasing public concern, few European and other countries worldwide have taken legislative steps against microbeads, and even fewer against other microplastics used in cosmetic products, mainly because it is a common belief that cosmetic industries responded massively to the call for a phase-out. Although EU acted soon after scientists focused on microbeads' effects by restricting cosmetics with microbeads to bare the EU Ecolabel in 2014, there is still no European-wide ban, which will probably take place as of 2022. Present study offers a thorough literature review on the presence of microbeads in cosmetics up to date, focusing primarily on the actions against their use, and questioning whether future pollution from microbeads or/and microplastics in cosmetics has been successfully handled.
Mostrar más [+] Menos [-]Heavy Metal Removal from Wastewater by Adsorption with Hydrochar Derived from Biomass: Current Applications and Research Trends
2021
Babeker, Tawasul Mohammed Ali | Chen, Quanyuan
PURPOSE OF REVIEW: Hydrothermal carbonization (HTC) is an innovative technique by which a wet feedstock is converting into valuable product, hydrochar, without drying as a pretreatment step. Over all other thermal converting process, HTC is counted as the most cost-effective and environmentally friendly technique. The purpose of this review is to highlight the current research trends of HTC and the application of hydrochar derived from biomass in heavy metal removal. RECENT FINDINGS: This review provides an overview about HTC fundamentals including its ecotoxicology and the factors such as biomass type, reaction temperature, retention time, catalysis, and pH medium, which affect hydrochar composition and performance. Moreover, various modification agents in order to function the hydrochar was discussed. It is proposed that the co-hydrothermal carbonization of two or more biomasses with the addition of other materials can enhance the functional groups and change the features of the produced hydrochar. This paper also reviews the kinetic analysis and adsorption isotherm as well as the hydrochar applications in heavy metal removal. Acacia arabica waste is produced annually in huge amount, which adversely affect the environment. Up to now, it has no specific reuse in a proper way. In this respect, biomass such as Acacia arabica wastes can successfully be valorized by converting into hydrochar via hydrothermal carbonization. Moreover, application as a green adsorbent to remove heavy metal contamination from wastewater due to its high porosity and great surface area is counted as a promising technique that contributes to this field of research.
Mostrar más [+] Menos [-]Occurrence, Toxicity, and Removal Methods of Triclosan: a Timely Review
2021
Wang, Yuewei | Liang, Wei
PURPOSE OF REVIEW: Triclosan (TCS) is a broad-spectrum antimicrobial agent that has been widely used in pharmaceutical and personal care products. TCS enters the environment mainly in effluent and biosolids from wastewater treatment plants, and persists in the aquatic environment and edatope. TCS is potentially harmful to the environment and biohealth because of its properties, being lipophilic, accumulative, toxic, and persistent. Therefore, TCS has become a research hotspot in recent years. The purpose of this review is to summarize the occurrence, toxicity, ecological effects, and removal methods of TCS. RECENT FINDINGS: TCS has a long half-life, and is found widely in the environment. Toxicity and ecological effects of TCS have been found in recent studies. Moreover, TCS has joint effects with multiple pollutants, and many of its transformation products are also toxic. Methods to remove TCS from the environment include adsorption, advanced oxidation technology, ecological engineering, and applying multiple methods in tandem. Each method is constantly being updated. This paper reviews recent research done on TCS, focusing on its occurrence, toxicity, ecological effects, and removal. Finally, several perspectives for research on this substance are outlined.
Mostrar más [+] Menos [-]Anthropogenic impact on Indonesian coastal water and ecosystems: Current status and future opportunities
2021
Adyasari, Dini | Pratama, Mochamad Adhiraga | Teguh, Novi Andriany | Sabdaningsih, Aninditia | Kusumaningtyas, Mariska Astrid | Dimova, Natasha
Indonesia, the world's largest archipelagic country and the fourth most populated nation, has struggled with coastal water pollution in the last decades. With the increasing population in coastal urban cities, more land-based pollutants are transported to the coastal water and adversely affected the tropical ecosystems. This paper provides an overview of anthropogenic pollutant studies in Indonesian coastal water and ecosystems from 1986 to 2021. Nutrients, heavy metals, organic pollutants, and plastic debris are the most-studied contaminants. We found that 82%, 54% and 50% of the studies exceeding nutrients, heavy metals, and organic pollutants standard limit, respectively; thus, indicating poor water quality status in part of Indonesian coastal water. The coral reef ecosystems is found to be the most sensitive to anthropogenic disturbance. The potential effect of climate change, new coastal pollution hotspots in eastern Indonesia, marine anthropogenic sources, legacy/emerging pollutants, and the need for research related to the biological contamination, are discussed for future opportunities.
Mostrar más [+] Menos [-]Aquatic contaminants in Solomon Islands and Vanuatu: Evidence from passive samplers and Microtox toxicity assessment
2021
Smith, A.J. | Barber, Yehonatan | Davis, S. | Jones, C. | Kotra, K.K. | Losada, S. | Lyons, B.P. | Mataki, M. | Potter, K.D. | Devlin, M.J.
Water Quality issues in many Pacific countries are rising, with the increase in coastal populations and associated urban runoff but management requires contamination issues in the aquatic environment to be identified and prioritised. In Vanuatu and Solomon Islands there are few laboratories and resources to assess for the presence or impact of complex chemical contaminants. The extent and impact of chemical contamination of the marine and coastal environment is poorly described.Passive chemical samplers were used to measure a range of aquatic pollutants around the capital cities, Honiara (Solomon Islands) and Port Vila (Vanuatu). We detected a range of chemicals indicative of agricultural and industrial contamination and a few sites had concerning concentrations of specific hydrocarbons and pesticides. The rapid ecotoxicology test, Microtox, indicated toxic impacts in rivers, coastal sites and urban drains This work provides new data on chemical contamination and possible impacts of that contamination for both countries. The techniques could be applied widely across the region to generate critical data for environmental management, guide monitoring efforts and measure the impact of policy or land-use changes.
Mostrar más [+] Menos [-]Changes in benthic macrofauna in oyster parks during an OsHV-1 μVar oyster spat mortality outbreak
2021
Vanhuysse, Charles | Normand, Julien | Lepoittevin, Mélanie | Orvain, Francis
In intertidal areas, oyster farming creates a crosshatching pattern between oyster tables and aisles. Tables provide a refuge from the current and solar irradiance and the oysters facilitate the accumulation of OM, thereby structuring the spatial organization of the associated macrozoobenthic community at mesoscale. The aim of this study was to describe the quality of the oyster table environment at small scale and the response of the macrozoobenthic community to OsHV-1 μvar oyster mortality. The species assemblage was dominated by Golfingia vulgaris, Tubificoides benedii, Capitella capitata and Scoloplos armiger. The table habitat appeared to be in a bad ecological state throughout the 2-month survey (May and June 2017), whereas in the aisle, eutrophication occurred lately and was clearly related to be due to the massive stranding of dead seaweed at the end of the survey (in early July). So, this disturbance of the species assemblage seemed to occur in two phases: 1) after oyster spat mortality and 2) after seaweed stranding resulted in a bad ecological status, as revealed by macrofaunal indicators. Large quantities of OsHV-1 DNA were also found in some species, including small crabs and amphipods, one week after the mortality crisis, but there is no apparent virus reservoir found in the benthic species.
Mostrar más [+] Menos [-]Allelopathic effects and potential allelochemical of Sargassum fusiforme on red tide microalgae Heterosigma akashiwo
2021
Sun, Siqi | Hu, Shanshan | Zhang, Bo | Sun, Xue | Xu, Nianjun
In this study, we aim to explore the allelochemicals of marine brown algae Sargassum fusiforme and the mechanism of allelopathy effect on Heterosigma akashiwo. Six potential allelopathic substances, palmitic acid, arachidonic acid, α-linolenic acid (ALA), fucosterol, 24-hydroperoxy-24-vinylcholesterol, and saringosterowere, were isolated and identified from S. fusiforme by column chromatography, NMR, TOF-MS and GC‐MS analyses. The ALA and 24-hydroperoxy-24-vinylcholesterol showed remarkable inhibitory activities on H. akashiwo growth. Besides, the allelopathic mechanism between the ALA and H. akashiwo was preliminarily investigated. The results indicated that the activities of SOD and POD of H. akashiwo gradually decreased under high ALA concentration. The reduction of photosynthetic pigments and chlorophyll fluorescence parameters, as well as apparent electron transport rate in H. akashiwo cells, aggravated gradually with increasing the concentration of the ALA. In summary, this study revealed the responses of morphology and physiology of H. akashiwo when exposed by ALA, while revealing the potential of macroalgae in red tide control.
Mostrar más [+] Menos [-]Fate and transport of coastal driftwood: A critical review
2021
Murphy, Enda | Nistor, Ioan | Cornett, Andrew | Wilson, Jessica | Pilechi, Abolghasem
Driftwood originating from natural and anthropogenic sources is abundant in coastal regions and plays an important role in ecosystems, providing habitat, structure, nutrients, and carbon storage. Conversely, large accumulations of driftwood can litter coastal zones, negatively impact coastal ecosystems and pose hazards to navigation, infrastructure and communities. Knowledge of the processes underlying the fate and transport of coastal driftwood is therefore needed to inform sustainable management practices. The present state of understanding is limited, and predominantly founded on studies of rivers and tsunamis, where the spatio-temporal scales and driving processes are significantly different from typical climatic or storm conditions in coastal waters. The authors critically review research on fate and transport of driftwood in coastal waters, and identify research needs and opportunities. Key knowledge gaps relate to: interactions between driftwood, littoral zone hydrodynamics and geomorphology; mechanisms of driftwood rafting and accumulation; and influence of weathering and degradation on mobility.
Mostrar más [+] Menos [-]An optimized procedure for extraction and identification of microplastics in marine sediment
2021
Liu, Yandong | Gao, Fenglei | Li, Zhaozhao | Ding, Huiping | Zhang, Dahai | Feng, Lijuan | Li, Xianguo
Microplastics (MPs) in sediment environments have been widely reported. As the number of samples increases, establishing a reliable and effective method becomes increasingly urgent for the rapid extraction and identification of MPs in sediments. Herein, we proposed a system with continuous density flotation of NaBr-ZnCl₂ (mixture of NaBr and ZnCl₂) solution for extracting MPs in a sediment sample, combined with micro-Fourier transform infrared (μ-FT-IR) imaging scanning for identification of MPs. The recoveries of MPs were estimated for four different sizes, shapes, and ten different types of polymers. The results indicated NaBr-ZnCl₂ solution showed a high recovery rate from 88.33% to 100.00% for extracting these different MPs. The μ-FT-IR imaging scanning allows for the detection of plastic down to the size of 6.25 μm in filed samples, and merely takes about 3 min, which was validated by testing of sediments from Jiaozhou Bay, China and its adjacent estuaries.
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