1,721,131 research outputs found
Single contaminant and combined exposures of polyethylene microplastics and fluoranthene:accumulation and oxidative stress response in the blue mussel, Mytilus edulis
No full textThe microplastic “vector effect” has received increasing attention. The aim of this study was to investigate the influence of polyethylene microplastic beads (PE MP) on accumulation and associated oxidative stress responses attributed to fluoranthene (Flu) in blue mussels, Mytilus edulis. Blue mussels were exposed for 96 h to four treatment groups: Flu-only, MP-only, Flu and MP coexposure, and Flu-incubated MP. Treatments were conducted at a low and high concentration (50 μg/L and 100 Flu μg/L and 100, and 1000 MP/mL). Results demonstrated that in both the gill and digestive gland, coexposure did not markedly affect Flu uptake, but this treatment significantly decreased tissue Flu concentrations. Antioxidant responses including activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidases (GPx), and levels of total glutathione (GSH) in both gills and digestive glands were significantly altered suggesting a perturbation of redox state induced by the exposure conditions. Although individual biomarkers varied, the biomarker profile enabled certain generalizations to be made. Antioxidant responses occurred more likely in gill tissue than in digestive gland. Individual contaminant exposures to Flu or MP led to varying responses, but coexposures and incubated exposures did not result in additive or synergistic effects. Exposure concentrations (i.e., low or high treatments) were not a consistent a predictor of response; and the internal Flu dose did not consistently predict outcome of various biomarkers. Importantly, MP-only exposure appeared to be capable of eliciting direct effects on the oxidative stress system as demonstrated by the activities of CAT and GPx. These findings warrant further investigation
Plastic Packaging in the Grocery Industry
No full textI Danmark generes der store mængder plastemballageaffald direkte og indirekte fra dagligvarehandlen, dog bidrager dette til miljømæssige ulemper. Dagligvarehandlen har en essentiel position i plastemballagens forsysningskæde, hvorfor dette speciale, med udgangspunkt i et casestudie af MENY Borups Allé, kortlægger plastemballager og dertilhørende problematikker repræsenteret her. Med et teoretisk afsæt i Green Supply Chain Management, har kortlægningen bidraget med indblik i, hvorledes det er muligt at forandre den måde plastemballage anvendes og hvorledes dagligvarehandlen kan medvirke til at facilitere øget miljøperformance for plastemballage. Kortlægningen er udført baggrund af en screening, hvori der anvendes observationsguide, stakeholder involvement, samt en vurderingsguide der benyttes som et analytisk værktøj. Specialets resultater belyser otte problematikker forbundet med at øge plastemballagers miljøperformance. Analysen tydeliggøre forskellige handlingsmuligheder for disse problematikker afhængig af positionen i forsyningskæden og eksterne faktorer. Specialet konkludere heraf, at de problematikker hvor MENY Borups Allé har direkte handlingsmuligheder er placeret centralt i forsyningskæden.In Denmark large amounts of direct and indirect waste from plastic packaging are generated from the grocery industry. This, however, has environmental downsides. The grocery industry holds an essential position in the supply chain of plastic packaging, which is why this thesis will assess plastic packaging and its related issues based on a case study of MENY Borups Allé. With a theoretical starting point in Green Supply Chain Management the outline has provided an insight into the possibilites of changing the use of plastic packaging and the contribution of the grocery industry in facilitating a greater environmental performance for plastic packaging. The identification has been made on the basis of a screening using an observation guide, stakeholder invovlement and color code assessment employed as an analytical tool. The findings of the thesis illustrate eight issues involving the increase in environmental performance of plastic packaging. The analysis clarifies various options for action depending on the position in the supply chain and external factors. In consequence it is the conclusion of this thesis, that the issues, where MENY Borups Allé has direct options for action, are at the core of the supply chain
Substitution of DEHP as Softtener in Medical Equipment
No full textIn this study the issue of phthalate softeners in medical equipment was examined. Phthalates, including di(2-ethylhexyl) phthalate (DEHP), have long been suspected for being carcinogenic or toxic for reproduction. Based on the latter DEHP in 2008 entered REACH’s authorization list with accompanying prohibition of industrial use from July 2015. Medical devices are, however, excluded from REACH, wherefore patients continue to be exposed to DEHP during treatment. The aim of the study is, to analyze which factors are decisive for the substitution of DEHP as a softener in medical devices, by applying Geels' (2004) theory of change in sociotechnical systems. Based on interviews with the medico producer Coloplast, the Hospital of Glostrup and the organization The Ecological Council, as well as through literature, the problem was scrutinized. It was found that risk assessments are not capable of determine a definitive risk evaluation of DEHP, because different players do not agree upon analysis of the underlying data. It was also found that while the European law left little possibility for a stricter regulation because of lobbyism from the industry, the Danish government has several indirect and direct possibilities for strengthening the substitution of DEHP in medical devices. Lastly it was found that for a large part of the medical devises, alternative phthalate-free alternatives are available which can be used without compromising patient safety or the economy of the user. Insufficient political action to ensure market pull or law incentive was concluded as the decisive factor holding back the substituting of DEHP in medical devises.In this study the issue of phthalate softeners in medical equipment was examined. Phthalates, including di(2-ethylhexyl) phthalate (DEHP), have long been suspected for being carcinogenic or toxic for reproduction. Based on the latter DEHP in 2008 entered REACH’s authorization list with accompanying prohibition of industrial use from July 2015. Medical devices are, however, excluded from REACH, wherefore patients continue to be exposed to DEHP during treatment. The aim of the study is, to analyze which factors are decisive for the substitution of DEHP as a softener in medical devices, by applying Geels' (2004) theory of change in sociotechnical systems. Based on interviews with the medico producer Coloplast, the Hospital of Glostrup and the organization The Ecological Council, as well as through literature, the problem was scrutinized. It was found that risk assessments are not capable of determine a definitive risk evaluation of DEHP, because different players do not agree upon analysis of the underlying data. It was also found that while the European law left little possibility for a stricter regulation because of lobbyism from the industry, the Danish government has several indirect and direct possibilities for strengthening the substitution of DEHP in medical devices. Lastly it was found that for a large part of the medical devises, alternative phthalate-free alternatives are available which can be used without compromising patient safety or the economy of the user. Insufficient political action to ensure market pull or law incentive was concluded as the decisive factor holding back the substituting of DEHP in medical devises
Trophic Transfer of Nano- and Micro Sized Polystyrene Particles from Blue Mussel to Shore Crab
No full textProduktionen af micro- og nanoplastik er steget grundet den øgede efterspørgsel af plastikprodukter. Dette har resulteret i at 4,8 - 12,7 mio. tons plastik ender i havet hvert år, og plastikpartikler kan nu findes i alle delene af det marine miljø. I estuarier akkumulerer plastikpartikler sig tæt på direkte afstrømning, ved flodmundinger, ved kystlinjen og tæt på rensningsanlæg. Dette medfører, at plastikpartikler er tilgængelige for de organismer der bor i disse levesteder. Disse organimser inkluderer palgiske alger, filterfødere og bentiske ådselsædere. Denne specialeopgave vil forsøge, gennem eksperimentielt arbejde, at estimere om trofisk transport af mikro- (2µm) og nano- (50nm) polystyrenepartikler finder sted, fra Rhodomonas salina til blåmuslingen Mytilus edulis (L.) og videre til strandkrappen Carcinus manas (L.). Ydermere vil denne opgave fokusere på forskellen i størrelsen på partiklerne, og hvordan dette har effekt på skæbnen af partiklerne i de valgte organismer i sammenhæng med forskellige koncentrationer af partiklerne. Vi fodrede derfor muslinger med en blanding af 1ml Rhodomonas salina, samt 50nm eller 2µm polystyrenepartikler i en lav (50mg/L) og en høj (500mg/L) koncentration. Fluorescencen af partiklerne i prøverne blev målt med en ELISA læser. Vi fandt, at 50nm og 2µm transporteres gennem diæten fra muslinger til krabber. 50nm og 2µm partikler blev fundet i kostorganerne i muslingerne og krabberne. Vi fandt trofisk transport af 2µm partikler. 2µm partikler har translokeret til hepatopancreas i krabben som et resultat af krabbens mekanismer, der malede partiklerne ned til <100nm. Ud fra dette konkluderede vi, at trofisk transport af 50nm partikler ikke sker mellem muslinger og krapper, men transport gennem diæten gør. Ydermere fandt vi, at trofisk transport af 2µm partikler sker mellem muslinger og krabber med translokation af partiklerne til hepatopancreas i krabben. Videre studier omkring trofisk transport er nødvendig for at estimere skæbnen af partikler i forskellige fødekæder, da de organismernes biologiske mekanismer har effekt på denne skæbne. Ydermere skal eksperimentet vare i længere tid for at kunne vurdere de miljømæssige konsekvenser af trofisk transport af mikro- og nanoplastik.The production of micro- and nanoplastic has increased in response to the increased demand of plastic products. This has resulted in 4,8-12,7m tons of plastic to enter the ocean annually and plastic particles are now to be found in all areas of the marine environment. In estuaries plastic particles accumulates close to direct run-offs and rivers, at shorelines and close to treatment plants. This makes plastic particles available for the organisms living in these habitats including pelagic algae, filter feeders and benthic scavengers. This master’s thesis will, through experimental work, aim to estimate if trophic transfer of micro (2µm) and nano (50nm) polystyrene particles occurs from Rhodomonas salina to the blue mussel Mytilus edulis (L.), and further to the shore crab Carcinus manas (L.). Furthermore the thesis will focus on the size difference of the micro and nano particles and how this affects the fate within the organisms along with differences in exposure concentration. Therefore, we fed mussels with a mixture of 1ml of the Rhodomonas salina and 50nm and 2µm fluorescence polystyrene particles at a low concentration (50 mg/L) and a high concentration (500mg/L). The fluoresence of the particles in the samples was measured using an ELISA plate reader. We found that dietary transfer of 50nm and 2µm polystyrene particles does occur between the blue mussel and the shore crab. 50nm and 2µm particles was found in the dietary organs of the blue mussel and the shore crab. We only found trophic transfer of the 2µm particles in the shore crab. 2µm particles had translocated to the hepatopancreas as a result of the dietary mechanisms within the crab, grinding the plastic particles down to <100nm in size. From this we can conclude that trophic transfer of 50nm polystyrene particles does not occur from the blue mussel to the shore crab, but dietary transfer does. Furthermore trophic transfer of 2µm polystyrene particles does occur between the blue mussel and the shore crab with translocation to the hepatopancreas of the shore crab. Further trophic transfer studies of nano- and microplastic particles is necessary to assess the fate of the particles in different food chains, as the mechanisms of the chosen test species affects the fate of the plastic particles. Furthermore, the duration of the experiment should be kept long to more accurately asses the environmental consequences of trophic transfer of micro- and nanoplastics
Sustainable Solutions for Meat Packaging. Transitioning from single-use to multi-use plastic packaging in supermarkets
No full textEffects of different shapes of microplastics on Daphnia magna
No full textPlastic pollution is an emerging problem in the aquatic environment and various literature was published concerning this topic. The aim of this report, is to investigate and discuss if different shapes of microplastics (MP) have different effects on freshwater organisms, like D. magna . Soft fibers, hard fibers, fragments and microbeads were examined.After 48 hours of exposure, no ingestion of MP was observed. However, soft fibers were externally attached to the antennae and appendages of D. magna . In one third of the cases, the amount of fibers attached was so big that D. magna were incapable to swim. In order to recover, they were transferred into a MP-free medium for an additional 24 hours, but they were found dead afterwards. This indicates that microfibers potentially possess different dangers to the environment than the other shapes and therefore MP cannot be considered as one type of pollutant, disregarding the differences among them
Long-term Effects of CuO Nanoparticles on Hyalella azteca - Implications for Environmental Risk Assessment
No full textDue to the specific properties nanoparticles (NPs) are increasingly used in a wide range of products. The rapid development within the field has resulted in a demand for recon- siderations of the current risk assessment methods, as NPs differ greatly from their bulk counterparts and many factors including the toxic mechanisms are not yet fully understood. In this study, the effects of copper oxide nanoparticles (CuO NPs) on the freshwater amphi- pod, Hyalella azteca, were investigated in order to evaluate the ecotoxicological differences between the nano and the ionic form of Cu. The CuO NPs were characterised by DLS, zeta potential, TEM and dissolution. Juvenile organisms were exposed to 25, 50 and 100 μg Cu/L added as either CuO NPs or CuCl2 in water for 50 days. Effects on growth, mortality, pre- copulation as well as bioaccumulation were measured. Potential delayed effects and ability to recover from Cu exposure were further assessed by transferring half the organisms to clean environment after 25 days of exposure. Growth inhibition as well as lack of precopulation was observed for organisms exposed to CuCl2 at all concentrations. The organisms transferred to clean environment after CuCl2 exposure showed similar effects, indicating no recovery from Cu exposure. Length and precopulation pattern of organisms exposed to either of the CuO NPs treatments were similar to that of control organisms. The risk assessment of NPs under REACH is subject to a number of challenges, due to the high diversity among NPs of the same chemical composition and knowledge gaps within fate and effects in the environment. Further, methods for particle characterisation and standard- ised test guidelines needs to be re-evaluated, as these are important for the risk assessment process. The current risk assessment methods have been evaluated for applicability to NPs and a range of additional physical-chemical properties and ecotoxicological endpoints have been recommended. However, current registration of NPs does not consistently take these into account, resulting in inconsistent registrations of NPs. The effects observed in the experiment are likely to result from the release of Cu ions, as the ion release in the dissolution study was five times higher for CuCl2 than for the CuO NPs. This was supported by calculations based on ionic effect concentrations of CuCl2 and CuO NPs. However, other studies have shown effects of the particles themselves or a combination of particles and ions further supporting the demand for nano-specific test guidelines.Due to the specific properties nanoparticles (NPs) are increasingly used in a wide range of products. The rapid development within the field has resulted in a demand for recon- siderations of the current risk assessment methods, as NPs differ greatly from their bulk counterparts and many factors including the toxic mechanisms are not yet fully understood. In this study, the effects of copper oxide nanoparticles (CuO NPs) on the freshwater amphi- pod, Hyalella azteca, were investigated in order to evaluate the ecotoxicological differences between the nano and the ionic form of Cu. The CuO NPs were characterised by DLS, zeta potential, TEM and dissolution. Juvenile organisms were exposed to 25, 50 and 100 μg Cu/L added as either CuO NPs or CuCl2 in water for 50 days. Effects on growth, mortality, pre- copulation as well as bioaccumulation were measured. Potential delayed effects and ability to recover from Cu exposure were further assessed by transferring half the organisms to clean environment after 25 days of exposure. Growth inhibition as well as lack of precopulation was observed for organisms exposed to CuCl2 at all concentrations. The organisms transferred to clean environment after CuCl2 exposure showed similar effects, indicating no recovery from Cu exposure. Length and precopulation pattern of organisms exposed to either of the CuO NPs treatments were similar to that of control organisms. The risk assessment of NPs under REACH is subject to a number of challenges, due to the high diversity among NPs of the same chemical composition and knowledge gaps within fate and effects in the environment. Further, methods for particle characterisation and standard- ised test guidelines needs to be re-evaluated, as these are important for the risk assessment process. The current risk assessment methods have been evaluated for applicability to NPs and a range of additional physical-chemical properties and ecotoxicological endpoints have been recommended. However, current registration of NPs does not consistently take these into account, resulting in inconsistent registrations of NPs. The effects observed in the experiment are likely to result from the release of Cu ions, as the ion release in the dissolution study was five times higher for CuCl2 than for the CuO NPs. This was supported by calculations based on ionic effect concentrations of CuCl2 and CuO NPs. However, other studies have shown effects of the particles themselves or a combination of particles and ions further supporting the demand for nano-specific test guidelines
The Impacts of Plastic Pollution on Coral Reefs and its Correlation to Coral Cover
No full textThis report is about the impacts of plastic pollution on coral reefs. Coral reefs are an important ecosystem as they provide for a biodiverse habitat and economic benefits to society. The major impact plastic has on coral reefs is that it functions as a vector, assisting with the spread of diseases. The distribution of marine litter and coral cover in the Philippines, Australia, and Belize are analyzed to see if there is any kind of correlation. The data collected along the coast of one of the islands in Central Visayas from the Marine Conservation Philippines is divided by beach- and dive clean-up. There is more litter on the beach than in the water, and most of it is accumulated near the locations with the most tourists. Though the data does not correlate with the tourist season. In the Philippines, the data reveals that the majority of the litter consists of plastic while only an average of 25\% coral cover was recorded. A similar result was seen in Australia (with a coral cover of about 17\%), though the coral cover slightly increased when looking at Belize even though most of the marine litter collected is plastic. The ocean is an open system, therefore, it is hard to analyze how plastic affects corals when other stressors are also present in these ecosystems
A Human Health Risk Assessment of Polystyrene Nanoparticles - The effects on the human intestinal epithelium using the human cell line Caco-2
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