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Junk food: A preliminary analysis of ingested marine debris by hawksbill Eretmochelys imbricata and olive ridley Lepidochelys olivacea sea turtles (Testudines: Cheloniidae) from the eastern coast of the United Arab Emirates
2021
Yaghmour, Fadi | Al Bousi, Marwa | Al Naqbi, Halima | Samara, Fatin | Ghalayini, Thouraya
For the first time, the qualitative and quantitative characteristics of marine debris ingested by six hawksbill (Eretmochelys imbricata) and seven olive ridley (Lepidochelys olivacea) sea turtles from the Gulf of Oman coast of the United Arab Emirates were investigated. The numeric and gravimetric proportions of ingested marine debris obtained from the esophagus, stomach and intestines were quantified following categories of presumed sources, Marine Strategy Framework Directive (MSFD), rigidity, color and plastic polymer types. Marine debris was observed in 28.6% of olive ridley (x̅: 2.00 items; 4.83 g) and 83.3% of hawksbill specimens (x̅: 6.00 ± 2.32 items; 0.32 ± 0.24 g). Overall, the results of this preliminary study suggest that hawksbill sea turtles were ingesting marine debris at higher frequencies and that plastics were observed to be the most predominant debris ingested. However, non-plastic rubbish, particularly metallic fishing gear (fish hooks and fish traps), were observed to present lethal hazards for both species.
Mostrar más [+] Menos [-]The importance of a functional approach on benthic communities for aquaculture environmental assessment: Trophic groups – A polychaete view
2021
Sanchis, Carlos | Soto, Eulogio H. | Quiroga, Eduardo
Polychaetes were studied to assess the effect of aquaculture activity on the seafloor. Very high biodiversity of species was recorded associated with aquaculture centres with Cirratulidae, Spionidae and Paraonidae families being the most diverse and abundant families. The spatial distribution of polychaete trophic groups was the best descriptor for detecting changes on the benthos. Surface and subsurface deposit-feeding species dominated the sites closest to the rafts cages, highlighting Capitella capitata and Cirratulus cirratus as opportunistic species. While replacement and species succession were observed with increasing presence of carnivores and omnivores in sites further away from the salmon cages and experiencing less impact. Analyses based on the distance of feeding modes and ecological groups from the disturbance source were better indicators of the impact that the traditional community approach or sediment biogeochemistry. Therefore, functional traits studies should always be considered on environmental assessments of benthic systems impacted by aquaculture.
Mostrar más [+] Menos [-]Health risk assessment of arsenic and some heavy metals in the edible crab (Portunus trituberculatus) collected from Hangzhou Bay, China
2021
Bao, Cong | Cai, Qiang | Ying, Xuanyu | Zhu, Yin | Ding, Yinjie | Murk, Tinka A.J.
In 2018, 108 swimming crabs (P. trituberculatus) were collected from the local market in Zhoushan. Each crab was separated into huang (the edible lipid portion) and meat groups and prepared according to different cooking methods. In most uncooked samples the levels of seven trace metals; mercury, cadmium, lead, zinc, copper, chromium and arsenic were higher in huang than in meat. Cadmium and total arsenic concentrations exceeded the maximum safe residue levels for China. Risk assessments revealed that only the cadmium levels in huang samples posed a toxicological risk to consumers, and uncooked huang were of carcinogenic concern. Cooking methods eliminated the carcinogenic risk and reduced the toxicological risk in huang by approximately 20%. These results show that the seven trace metals identified in P. trituberculatus from Hangzhou bay do not pose a safety concern for consumption of the meat or of the complete crab, after conventional cooking.
Mostrar más [+] Menos [-]Nivar cyclonic impacts on mollusk habitat destruction in Parangipettai, southeast coast of Tamil Nadu, India: A case study
2021
Gunasekaran, K. | Kārttikēyan̲, Pa. | Yosuva, M. | Manigandan, V. | Subagunasekar, M.
Tropical storms form in the Bay of Bengal every year during the pre-monsoon season, affecting the coastal communities and the marine ecosystem. On November 25, 2020, severe cyclone Nivar impacted the southeast coast of Tamil Nadu, causing massive damage to marine benthic species. The study found that the Nivar cyclone's high velocity wind impacted tidal currents and damaged sediment compartments. This phenomenonhas immensely affected the benthic communities of Mudasalodai, Parangipettai, Puthupettai, Samiyarpettai, and Kumarapettai. Post-Nivar cyclone observations revealed massive bivalve and gastropod mortality. The two molluscan species lost their habitats due to the tremendous cyclone effect. More than 1 lakh Mactra violacea were emigrated from Parangipettai and 5 lakh Turritella acutangula and T. attenuata were emigrated from Samiyarpettai. Thus, the Nivar cyclone severely damaged mollusk habitats along India's southeast coast. The severe cyclonic storm Nivar disrupted the southeast coast of India, with losses amounting to over $600 million.
Mostrar más [+] Menos [-]Sub-lethal combined effects of illicit drug and decreased pH on marine mussels: A short-time exposure to crack cocaine in CO2 enrichment scenarios
2021
da Silva Souza, Lorena | Bonnail, Estefanía | Maranho, Luciane Alves | Pusceddu, Fabio Hermes | Cortez, Fernando Sanzi | Cesar, Augusto | Ribeiro, Daniel Araki | Riba, Inmaculada | de Souza Abessa, Denis M. | DelValls, Ángel | Pereira, Camilo Dias Seabra
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.
Mostrar más [+] Menos [-]Sources of marine litter along the Bulgarian Black Sea coast: Identification, scoring and contribution
2021
Chuturkova, Rozalina | Simeonova, Anna
The sources of marine litter (ML) pollution along the Bulgarian Black Sea coast in 2019 were identified and categorized to: Public litter, Fishing, Shipping, Sanitary and sewage, Fly tipped, Medical and Non-sourced, following Veiga et al., 2016 approach. Largest was the contribution of Public litter - 48.3% and Non-sourced - 38.5% of the total. Most Public litter items were attributed to recreational activities - 82.9% Public litter Recreation and less to Public litter Smoking-related - 17.1%. Regarding to Non-sourced, the following sub-categories seemed to contribute clearly more: Land (run off) - 8.79% and Tourism beach users - 8.58%. Considerably lower was the contribution of Fishing, Offshore and Shipping. None of the items were attributed to Sewage related. The ML pollution on the individual beaches (10 sites) exhibited largest contribution of Public litter with most significant input of Public litter Recreation, varying from 65.9 to 86.7% between beaches.
Mostrar más [+] Menos [-]Microplastic contamination in salt pans and commercial salts – A baseline study on the salt pans of Marakkanam and Parangipettai, Tamil Nadu, India
2021
Nithin, A | Sundaramanickam, A | Surya, P | Sathish, M. | Soundharapandiyan, B | Balachandar, K
We studied the abundance of microplastics from commercial table salts and table salts from salt pans at Marakkanam and Parangipettai, Tamil Nadu, India. Microplastic abundance in the salts collected from salt pans had a range of 3.67 ± 1.54 to 21.33 ± 1.53 nos./10 g of salt which were higher than the microplastics retrieved from the commercial salts which ranged from 4.67 ± 1.15 to 16.33 ± 1.53 nos./10 g of salt. All the microplastics retrieved were fibers which were secondary in origin. Black, red, blue, green, white, brown, and colorless microplastics were observed in the samples. FT-IR results showed that 4 types of polymers, namely, Nylon, Polypropylene (PP), Low Density Polyethylene (LDPE), and Polyethylene Terephthalate (PET) were present in the samples. Domestic and municipal wastewater discharges into the estuaries may contribute to microplastics in the table salts. Our study proves that table salts (processed and unprocessed) are prone to microplastic contamination.
Mostrar más [+] Menos [-]Overview and Research Progresses in Chemical Speciation and In Vitro Bioaccessibility Analyses of Airborne Particulate Trace Metals
2021
Zhao, Zhen | Jing, Yuanshu | Luo, Xiao-San | Li, Hanhan | Tang, Mingwei
PURPOSE OF REVIEW: As a priority environmental pollutant, toxic trace metals enriched in atmospheric particulate matters (PMs) pose potential threats to both ecological system and human health. To sufficiently clarify the relationships between airborne trace metals and environmental impacts, considering the chemical speciation and bioaccessibility of trace metals in PMs becomes necessary. RECENT FINDINGS: In this mini-review, such recent research progresses were summarized, including the concepts and developed methods for metal fractionation and bioaccessibility evaluation, especially the human body (lung)–related bioaccessible fractions of inhalable particle metals. Chemical extraction methods for different fractions and a compilation of in vitro bioaccessibility approaches for trace metals in PMs were presented. For future risk assessments and toxicity tests of atmospheric particulate metals, incorporating the bioaccessibility supported by standardized speciation methods are directions.
Mostrar más [+] Menos [-]Occurrence, characterization, and ecological assessment of petroleum-related hydrocarbons on the shoreline of Fraser River Delta, British Columbia, Canada
2021
Yang, Zeyu | Shah, Keval | Laforest, Sonia | Cardinal, Emile | Lambert, Patrick | Hollebone, Bruce P. | Brown, Carl E. | Goldthorp, Michael | Waston, Kevin | Yang, Chun | Durand, William
The Fraser River Delta is a unique and dynamic region supporting the diverse ecosystems and habitats in the Canadian West Coast. Total petroleum hydrocarbons (TPH), n-alkanes, petroleum biomarkers, and polycyclic aromatic hydrocarbons (PAHs) were analyzed for the intertidal sediments taken from the shorelines of the Delta area, British Columbia, Canada, to establish the baseline background data. Most of the sampling sites had low TPH (< 40 μg/g); only two samples had TPH from 100 to 150 μg/g. Mainly biogenic n-alkanes were present in all sites. Non-detectable to trace amounts of petroleum biomarkers were found at most sites. Mixed pyrogenic and petrogenic inputs contributed to the presence of PAHs at most sites. PAHs are not present in amounts anticipated negative effects to benthic organisms in all sampling sites, except that benzo (a) pyrene (BaP) from the upper intertidal zone (UIZ) of Burnaby Fraser Foreshore Park may have possible adverse biological effects.
Mostrar más [+] Menos [-]Essential and non-essential heavy metal levels in key organs of winter flounder (Pseudopleuronectes americanus) and their potential impact on body condition
2021
Foley, M. | Askin, N. | Belanger, M.P. | Wittnich, C.
This study explored whether winter flounder, a benthic species, are potentially exposed to contaminants such as heavy metals released from the sediment of the Bay of Fundy/Gulf of Maine, both critical habitats identified to have increases in heavy metal levels. Experimentally in fish, exposure to certain heavy metals resulted in reduced weight for length and structural abnormalities, but it is unknown if this occurs in wild fish. Winter flounder (n = 72), harvested between 2015 and 2018 from the aforementioned western Atlantic region of Canada/USA, had detectable levels of most heavy metals, with some exhibiting levels of concern (arsenic, cadmium, lead, selenium, zinc) in muscle, liver, and kidney. A 1.4% incidence of structural abnormalities was noted. When compared to 1980 regionally matched flounder data, the 2018 flounder had significantly reduced weight for length, exacerbated with age. Clearly winter flounder are affected by worsening heavy metal contaminant levels in this geographic area.
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