1,720,965 research outputs found
Litter & microplastics features in table salts from marine origin: Italian versus Croatian brands
Full text linkThis study estimates litter content, including microplastics, mesoplastic, and macroplastic in marine table salts coming from Italy and Croatia. Both high (HC) and low (LC) costs commercial brands easily found at the supermarket were analysed. Any macroplastic or mesoplastic were recovered while microplastics and other litter impurities significantly affect table salts of all tested brands. Average microplastic values ranged within 1.57 (HC) – 8.23 (LC) (Italy) and 27.13 (HC) – 31.68 (LC) items/g (Croatia). Microplastics sizes (min-max) ranged within 4–2100 μm (Italy) and 15–4628 μm (Croatia). In samples from both Nations, a significant general positive correlation between the average number of items/g recorded and the total amount of general impurities was recorded. Concerning microplastic shapes, in Italy, fragments dominated even if fibres, granules, films, and foams are frequently recorded. On the contrary, clear PP fibres dominated in Croatian brands even if also other shape classes were recorded
Ecotoxicity of nano-metal oxides: A case study on daphnia magna
Full text linkIn Europe REACH framework directive imposes data acquisition concerning toxicity on acquatic species before the commercialization of chemicals to assess environmental risks. According to official methods, exposure tests are performed under in vitro and standardized conditions: OECD’s guideline rules external variables such as water type, feeding conditions, and exposure time. As consequence, such obtained results could be different from effects observed in natural environments. This study collects effects within 24–96 h of exposure to nano metal-oxides (ZnO, TiO2) on D. magna obtained by the exposure under standard OECD conditions comparing them with results obtained by the exposure under more similar conditions to natural environment (i.e. mixture, feeding). High doses exposure determines gas-bubble disease. Animals exposed to LC10 actively ingest nanoparticles under both fasting and feeding conditions. Furthermore, body burial by a coat of nanoparticles thicker in mixtures than in single dispersions was recorded. Furthermore, results show that: (i) effects increase over time; (ii) n-ZnO results less effective than n-TiO2 in both single dispersion, and mixture; (iii) the presence of surfactant increases toxicity of nanoparticles; (iv) immobilization is a more sensitive endpoint than mortality; (v) feeding increases test sensitiveness improving differences among treated and controls till 96 h and allowing longer exposure times than standard OECD test. As general remark, this study provides evidence that in vitro ecotoxicological results obtained under standardized OECD conditions could be significant different to animals’ responses under natural (feeding and mixtures) exposure conditions
Chemical fingerprint of plastic litter in sediments and holothurians from Croatia: Assessment & relation to different environmental factors
Full text linkThis paper increases knowledge on litter transfer from sediments towards the trophic web throughout sea cucumbers, key protected benthic species. In October, sediment and holothurian samples from seventeen sampling sites from Croatian Islands characterized by different levels of protection (Silba n = 7; Telašćica MPA n = 10) were collected. Collected particles ranged in sediments within 113.4–377.8 items/kg d.w., and in holothurians within 0.6–9.4 items/animal, showing sizes within 1.4–10,493 μm. In holothurians, cellulose and cellulose acetate (non-synthetic materials) mean percentages were within 5.0–12.7% of the total amount of particles. Nylon fibres ranged within 0–26.7%; while PP, PE, PA, and PS% were more abundant than in sediments. Among factors of variability tested, “island group” and “level of protection” resulted to affect plastic composition in sediments. Otherwise, other environmental factors (i.e. orientation, morphology of sampling site, P. oceanica) were significantly related to chemical composition of microplastic ingested by holothurians
Microparticles in table salt: Levels and chemical composition of the smallest dimensional fraction
Full text linkThis study evaluates the chemical composition of microplastic materials (MPs) and non-synthetic particles in different table salts of marine origin by the μFT-IR technique. This research focuses on the microparticles fraction within 10-150 μm of size. Eleven commercial trademarks coming from Italy (IT = 6) and Croatia (CRO = 5) were grouped in two different cost ranges, cheap (n = 5) and expensive (n = 6) and were analysed in replicates (n = 3). Levels and chemical composition of microparticles measured in commercial products were correlated on a statistical basis to some factors of variability of potential scientific interest (geographical origin of marine salt, cost of commercial products, etc.). Results of analyses performed on the tested size fraction of microparticles (10-150 μm) evidence that: (i) levels of MPs are within 0.17-0.32 items/g (IT) and 0.07-0.20 items/g (CRO); (ii) non-synthetic particles detected are mostly made by fibres made of cellulose acetate; (iii) Nations show a different chemical composition of MPs recovered in analysed trademarks (PET and PVC from Italy; PA, PP, and nylon from Croatia); (iv) the annual amount ingested by humans from marine salt consumption ranges between 131.4-372.3 items/y (CRO) and 306.6-580.35 items/y (IT) considering a dose of 5 g of salt per day; (v) statistics performed on factors of interest evidenced that the geographical origin of marine salt do not affect neither levels nor chemical composition of MPs in tested trademarks; while slight correlations are recorded with non-synthetic particles. Further studies are needed to better explore on statistical basis if both levels and chemical composition of MPs in table salts of marine origin can be used or not as good indicators of marine pollution
Plastic litter in sediments from the Croatian marine protected area of the natural park of TelašČica bay (Adriatic Sea)
No full textThis paper reports baseline levels of litter (macro, meso and microplastics) in sediments collected from different areas of the Croatian MPA of the Natural Park of Telaščica bay (Adriatic Sea, GSA n. 17). The distribution of total abundance according to size, for all analysed locations evidences that microplastics are the dominant fraction concerning item's numbers. In all analysed samples no macroplastics were found, while microplastics are 88.71% and mesoplastics are 11.29% of the total
Effects of Different Microplastic Types and Surfactant-Microplastic Mixtures Under Fasting and Feeding Conditions: A Case Study on Daphnia magna
Full text linkThis study evaluates the mortality and immobilization on Daphnia magna after 24–96 h of exposure to microplastic dispersions (PP, PE, PVC, PVC/PE), and to microplastic + surfactant solutions both under fasting and feeding conditions. The tested microplastics were analysed with μFT-IR to determine their chemical composition, purity, and dimensions. The results show that: (i) exposure under fasting conditions produces acceptable results on negative controls no later than 24 h; (ii) the dispersion of microplastics forms homo-agglomerates that are able to affect animals’ motility and cause mortality and immobilization; (iii) different types of tested microplastic produce different effects on endpoints (the most toxic is PVC + surfactant); (iv) in all cases, the effects were reduced under feeding conditions (i.e. 4 times reduction of PE toxicity); (v) effects of surfactant on observed toxicity are microplastic-type dependent; (vi) the age of the animal affected the mortality and immobilization responses after exposure under both fasting and feeding conditions
Marine litter in sediments related to ecological features in impacted sites and marine protected areas (Croatia)
Full text linkThis study estimates levels of marine litter including plastics (macro-, meso- and microplastics) in sediments collected in shallow marine water from Croatia (Central Adriatic Sea). Selected sampling areas are characterized by different human pressure: Silba is highly stressed by tourism while Grebena is listed as marine protected area (MPA) of future institution. Obtained results on marine litter in sediments are correlated to ecological features recorded in each sampling site. Marine litter in collected sediments ranged within 180–528 items/kg d.w. Macroplastics were not recorded while mesoplastics were 1.3–4.8%. On a general basis, fibres are higher than microplastics. In Južni Greben, level of fragments higher than fibres was recorded. A slight significance of the factor “water depth” was evidenced by the statistical analyses exploring relationships among marine litter and ecological features. Furthermore, Silba and Grebena Islands showed a significant different assessment of size, shape and colour features. These results suggest different sources/dynamics affecting marine litter recorded in marine areas stressed by tourism compared to MPA
Plastic litter transfer from sediments towards marine trophic webs: A case study on holothurians
Full text linkThis study estimates for the very first time plastic litter levels in sea cucumbers (Echinodermata, Holothuroidea) sampled in situ and their intakes from sediments in three different rocky bottom habitats (slides, cliff, banks) settled in Salina Island (Aeolian Archipelago). Macroplastic were never recorded while meso- and microplastics were identified in all sediment (81–438 items/kg d.w.) and animal samples (1.8–22 items/ind.). Plastic intakes by sea cucumbers resulted frequently associated to the size range included within 100–2000 μm. Over than 70% of ingested plastic litter is represented by the size fraction >500 μm. Sediment/animals ratios % are included 2.7 ± 2.0% in studied habitats with a selective intake of fragments occurring in slides. Furthermore, results support the occurrence of selective ingestion of plastic litter by holothurians in natural environments underlining the role of these species in microplastic transfer from abiotic towards biotic compartments of the marine trophic web
Plastic levels in sediments closed to Cecina river estuary (Tuscany, Italy)
Full text linkThis study focuses on plastic distribution levels (shape, size, colour, type) in sediments from the coastal area of Cecina (Tuscany, Italy). Samples are collected in three sampling stations along six transect settled randomly along the shoreline and along the final tract of the Cecina river. Recorded plastic size ranges within 62.51–13,462 μm (average values 1591 ± 837 μm). Microplastics ( Fiber > Granule in each of the tested sampling site. Plastic litter levels recorded in study evidence low pollution compared to the existing literature supporting the occurrence of good environmental levels in Cecina coastline for the “Marine litter” descriptor
Microplastic contents from maricultured and natural mussels
Full text linkResults of this research focuses on microplastic contents (levels, type, size, colour) in maricultured and natural mussels (Mytilus galloprovincialis) from different Italian stocks. No significant differences were found among maricultured and natural stocks. All recovered MPs are filaments ranging within 750–6000 μm of maximum length (average values 1150–2290 μm). Feeding raw mussel could produce median MP intakes of 6.2–7.2 items/g w.w. Concerning human exposure by diet, both raw and cooked values are important. Some preliminary tests performed in this study evidenced that the cooking process determined lower MPs levels (−14%) in cooked tissues compared to raw ones, MPs were recorded in cooking water and were characterized by a lower size than in raw mussels. Results obtained by this study represent an important baseline on MPs level to evaluate environmental and human exposure risks by diet
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