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Comparison of trace element concentrations in freshwater fish and marine fish consumed in Shandong Province, China, and their potential risks to human health
2021
Yang, Luping | Guo, Mingcai | Xin, Chenglong | Ren, Xiaofei | Wang, Lin | Liu, Yongjun
This study provides the primary data of ten trace element concentrations from four highly consumed cultured freshwater fish species in comparison to six marine fish collected from markets of the Shandong province, China, and evaluates the potential human health risks from consuming these fish. A significant difference in five metal concentrations (Cr, As, Se, Cd, Pb) was found between freshwater and marine fish. With the exception of chromium, the other four element contents in marine fish were higher than those in freshwater fish. According to estimated daily intake (EDI), target hazard quotient (THQ), total target hazard quotient (TTHQ), and the permissible safety limits prescribed by various agencies, consumption of the examined fish species is safe for human health. However, chromium in freshwater fish and arsenic in marine fish should still be a cause for concern in terms of human health, especially for fisher folk communities and populations that frequently consume fish.
اظهر المزيد [+] اقل [-]Chemical characterization of variably degraded fibre glass reinforced plastic from the marine environment
2021
Hopkinson, Laurence | Ostapishin, Stanislav | Kristova, Petra | Hamilton, Katy | Ciocan, Corina
Glass reinforced plastic (GRP) constitutes the commonest component of small sea going craft of all descriptions. This study provides a baseline molecular and elemental account of GRP's recovered from the marine environment. Fourteen samples of GRP sourced from scrapyards and one sample sourced from a GRP boat manufacturer were examined. Samples were analysed by x-ray fluorescence and mid infrared (MIR). The latter technique confirmed that all samples contained the same polyester resin, poly diallyl phthalate (PDP). The two techniques in combination indicate the presence of aluminium calcium borosilicate E-glass fibres (E denotes electrical) of variable origins. MIR results are consistent with hydrolysis of polyester, weakening of the glass fibre resin interface facilitating exposure of e-type fibres to water which accelerates fibre breakage. The implication being that aging of GRP in the marine environment represent sources for micro (<5 mm) and macro plastic release, plus fragmented asbestiform-like silicate fibres.
اظهر المزيد [+] اقل [-]Environmental and human health impacts of cruise tourism: A review
2021
Lloret, Josep | Carreño, Arnau | Carić, Hrvoje | San, Joan | Fleming, Lora E.
The intensive growth of cruise tourism worldwide during recent decades is leading to growing concerns over the sector's global environmental and health impacts. This review combines for the first time various sources of information to estimate the magnitude of the cruise industry's environmental and public health footprints. This research shows that cruising, despite technical advances and some surveillance programmes, remains a major source of air, water (fresh and marine) and land pollution affecting fragile habitats, areas and species, and a potential source of physical and mental human health risks. Health risks impact both the people on board (crew and passengers) and on land (workers of shipyards where cruise ships are dismantled and citizens inhabiting cities with cruise ports and shipyards). In this context, we argue that the cruise industry should be held accountable with more monitoring and regulation to prevent or minimize the growing negative environmental and human health impacts.
اظهر المزيد [+] اقل [-]The barnacle Chthamalus bisinuatus is the only sessile invertebrate colonizing oil patches on beachrocks one year after a massive oil spill on the Northeastern Brazilian coast
2021
Gusmao, Joao Bosco | Albergaria-Barbosa, Ana C.R. | Kikuchi, Ruy Kenji P. | Combi, Tatiane
A large-scale oil spill has reached over 3000 km of the NE Brazilian coast since August 2019. The cause and origin of this spill remain mysterious, and the impacts on coastal ecosystems have not been clearly understood so far. Despite the efforts to remove the oil (mainly from local communities), oil stains are still present in beaches, mangroves, and beachrocks. In this short report, we describe the occurrence of the barnacle Chthamalus bisinuatus Pilsbry, 1916 colonizing oil spill stains on intertidal surfaces of beachrocks one year after the first oil records. We quickly assessed oil stains across three different reefs located at the Conde municipality, Bahia (NE Brazil), where the species was identified and its density on oil stains calculated. The occurrence of barnacles in oil stains was restricted to zones in the wake of the reefs. Their densities varied from 0 to 238 ind./dm², with an average of 34 ± 68 ind./dm². If we account for dead individuals (empty barnacle plates), they correspond to 25.9% of the sampled population. The presence of oil possibly affected barnacle survival rates but did not seem to prevent barnacle individuals from reaching adult sizes. We also found individuals of the snail Echinolittorina lineolata (d'Orbigny, 1840) crawling on these barnacles, indicating that the barnacle assemblages on oil stains are stable enough to provide refuge for these snails. It is not clear if the presence of barnacles on oil reflects the resistance of these crustaceans to the oil toxicity or is just a result of a low substrate selectivity by the cypris larvae.
اظهر المزيد [+] اقل [-]Microplastic changes the sinking and resuspension rates of marine mussel biodeposits
2021
Harris, Lyda S.T. | Gill, Harsimran | Carrington, Emily
Microplastic (MP; < 5 mm) is ubiquitous in marine environments and is likely transported by biotic benthic-pelagic coupling. Mussels are key benthic-pelagic couplers, concentrating particles from the water column into dense and nutrient rich biodeposits. This study examined how MP affects benthic-pelagic coupling processes of mussels exposed to feeding regimes with and without MP by measuring four attributes of biodeposits: 1) morphology, 2) quantity of algal and MP particles, 3) sinking rate, and 4) resuspension velocity. We found interacting effects of particle treatment and biodeposit type on biodeposit morphology. Biodeposits from the algae treatment contained more algal cells on average than biodeposits from the MP treatment. Biodeposits from the MP treatment sank 34–37% slower and resuspended in 7–22% slower shear velocities than biodeposits from the algae treatment. Decreases in sinking and resuspension velocities of biodeposits containing MP may increase dispersal distances, thus decreasing in-bed nutrient input and increasing nutrient subsidies for other communities.
اظهر المزيد [+] اقل [-]Stranded marine debris on the touristic beaches in the south of Bali Island, Indonesia: The spatiotemporal abundance and characteristic
2021
Suteja, Yulianto | Atmadipoera, Agus Saleh | Riani, Etty | Nurjaya, I Wayan | Nugroho, Dwiyoga | Purwiyanto, Anna Ida Sunaryo
Stranded marine debris (MD) has become a hot topic on Bali Island because it threatens coastal tourism sustainability. This study aims to investigate the spatiotemporal abundance and characteristics of MD on 14 touristic beaches in Bali Island. Sampling is carried out twice every season by adapting methods from NOAA's MD program. We found that the average MD abundance and weight were 0.356 ± 0.366 items/m² and 4.057 ± 3.892 g/m², respectively. Plastic dominated the MD based on abundance (86.9%) and weight (40.1%). Plastic bags, straws, and plastic cups are the most common items among plastics. The MD is originated from Indonesia and is dominated by land-based sources. The beaches are categorized as dirty in the rainy seasons and clean in the dry seasons. Statistically, the MD based on abundance, weight, category, source, and level of cleanliness varied significantly between seasons.
اظهر المزيد [+] اقل [-]Impact of polycyclic aromatic hydrocarbons in mangroves from the Colombian pacific coast: Evaluation in sediments and bivalves
2021
Angulo-Cuero, Jesús | Grassi, Marco Tadeu | Dolatto, Rafael Garrett | Palacio-Cortés, Angela María | Rosero-Moreano, Milton | Aristizábal, Beatriz H.
Bivalves and sediments were sampled from mangroves in the Pacific Coast of Colombia to evaluate the concentrations of the 16 polycyclic aromatic hydrocarbons (PAHs) prioritized by U.S.EPA. Mangroves are highly vulnerable to anthropogenic activities, such as oil spills, which affect sediments and the organisms that depend on that ecosystem. Twelve samples of mangrove and non-mangrove (sandy) sediments and 20 samples of Anadara tuberculosa from mangrove were collected in marine and estuarine areas. In sediments and A. tuberculosa, the highest concentration of Ʃ16PAHs was found in estuarine mangroves close to the Rosario River mouth, ranging from 171.4 to 564.0 ng g⁻¹ and 31.0 to 169.0 ng g⁻¹, respectively. For the bivalve, the concentrations showed less variability than sediment, with 25% and 20% of bivalve samples exceeding the limits established by the European Regulatory Commission and Ministry of Health and Social Protection of Colombia, respectively, which can cause effects on people's health. The PAHs isomeric ratios determined in sediments indicated that these compounds were originated mainly from petrogenic sources. The PAHs profile reveals the dominance of 3 and 4 rings PAHs in sediments and dominance of 4 rings PAHs in bivalves.
اظهر المزيد [+] اقل [-]Use of ecological concrete for nutrient removal in coastal sediment and its effects on sediment microbial communities
2021
Liu, Lemian | Ji, Jiannan | Guo, Yisong | Chen, Jianfeng
Ecological concrete (eco-concrete) can reduce excess nutrients (nitrogen and phosphorus) in water, but its effectiveness in removing nutrients in marine coastal sediments and the response of sediment microbial communities to its use are largely unknown. In this study, eco-concrete planted with Bruguiera gymnorrhiza was used to remove nutrients in marine coastal sediment. We found that the mean removal efficiencies of sediment total nitrogen and total phosphorus by using planted eco-concrete were 11.50% and 30.31% on day 60, and were higher than those obtained by only using B. gymnorrhiza (7.14% and 7.36%). the Diatoms and bacterial genera Fusibacter and Anoxynatronum (which belong to Firmicutes) increased and became the abundant microbes by day 60 when using planted eco-concrete, indicating their potential roles in nutrient removal. Moreover, the eco-concrete did not endanger the core microbes in sediment suggesting its environment-friendly character. Our results suggest a potential method to control marine coastal eutrophication.
اظهر المزيد [+] اقل [-]Surface-functionalised materials for microplastic removal
2021
Rius-Ayra, O. | Biserova-Tahchieva, A. | LLorca-Isern, N.
Microplastic (MP) pollution is a matter of great concern attracting increasing attention due to its adverse effects on the environment. Different technologies and methodologies have been developed to remove these pollutants. Herein, we focus on a promising environmental solution that involves surface modification to change the wettability properties of MPs or solid materials by conferring superhydrophobicity and superoleophilicity to increase the selectivity for MP separation. Both processes can be used to selectively separate MPs because of the changes in the wettable properties of the MP or by changing the oil used in the case of superhydrophobic surfaces. We show two distinct methods based on changing the wettability properties of surfaces that could lead to innovative and environmental applications. We also discuss some of the challenges that need to be overcome.
اظهر المزيد [+] اقل [-]Marine litter pollution on coral reefs of Darvel Bay (East Sabah, Malaysia)
2021
Santodomingo, Nadiezhda | Perry, Chris | Waheed, Zarinah | Syed Hussein, Muhammad Ali bin | Rosedy, Allia | Johnson, Kenneth G.
Marine litter is recognized as an increasing component of marine ecosystem pollution. In this baseline study, we document the magnitude, types, sources, and potential impacts of litter on six coral reefs in East Sabah. We applied a simplified classification of litter to extract abundance data from video transects. The average density was 10.7 items per 100 m². Plastics represent 91% and the remaining 9% were metal, glass, and wood. Most (~70%) plastics are single-use items derived from dumping. Discarded fishing gear accounts for ~25%. Litter pollution increases closer to urban developments, with Sakar reef having higher densities (51 items per 100 m²), and higher Clean Coast Index (CCI = 10.2, dirty) and higher Plastic Abundance Index (PAI = 4.68) scores. This method could and should be readily integrated into ongoing monitoring programs to support assessments of the extent and magnitude of marine litter pollution on reefs worldwide.
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