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1.
Environ Sci Technol ; 57(8): 3218-3227, 2023 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-36791268

RESUMEN

In the marine environment, discarded cigarette filters (CFs) deteriorate and leach filter-associated chemicals. The study aim was to assess the effects of smoked CFs (SCFs) and non-smoked CFs (NCFs) particles on individual life-history traits in the deposit-feeding polychaete Capitella teleta and extrapolate these to possible population-level effects. C. teleta was exposed to sediment-spiked particles of NCFs and SCFs at an environmentally realistic concentration (0.1 mg particles g-1 dw sed) and a 100-fold higher (10 mg particles g-1 dw sed) concentration. Experimental setup incorporated 11 individual endpoints and lasted approximately 6 months. There were significant effects on all endpoints, except from adult body volume and egestion rate, in worms exposed to 10 mg SCF particles g-1 dw sed. Although not statistically significant, there was ≥50% impact on time between reproductive events and number of eggs per female at 0.1 mg SCF particles g-1 dw sed. None of the endpoints was significantly affected by NCFs. Results suggest that SCFs are likely to affect individual life-history traits of C. teleta, whereas the population model suggests that these effects might not transform into population-level effects. The results further indicate that chemicals associated with CFs are the main driver causing the effects rather than the CF particles.


Asunto(s)
Poliquetos , Productos de Tabaco , Contaminantes Químicos del Agua , Animales , Femenino , Sedimentos Geológicos , Contaminantes Químicos del Agua/análisis , Reproducción
3.
J Environ Manage ; 302(Pt A): 113975, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-34700081

RESUMEN

Although plastic is one of the most commonly used materials in our everyday life, the current linear economy ('produce, use and dispose') engenders high risks to human health in relation to greenhouse gas (GHG) emissions and environmental pollution. As a response to these challenges, the circular plastic economy is gaining momentum, where the goal is to reduce, reuse and recycle all plastic. The transition to the circular economy should be made across the entire plastics value chain in order to ensure circular design, production, use and waste management. This study examines the current scientific literature in relation to the entire value chain of plastics. This aim of the article is to provide an overview of the existing research (and highlight research gaps) associated with the transition of plastic use to a circular model. The literature was divided into the following categories: 1) design; 2) production; 3) use; 4) end-of-life; and 5) value chain. A high proportion of the literature was found to address the end-of-life phase, suggesting that the other phases are currently neglected. The results have implications that are applicable to multiple phases; in particular, contamination of waste streams and composite materials places significant limitations on the opportunity to recycle and reuse plastic in new products. This calls for changes in the whole value chain, and for trans-sectorial collaboration to ensure systemic transparency. Therefore, future research should take a holistic approach to the transition to circular through careful mapping of implications, stakeholder involvement and collaboration.


Asunto(s)
Gases de Efecto Invernadero , Administración de Residuos , Humanos , Plásticos , Reciclaje
4.
J Toxicol Environ Health A ; 82(10): 616-625, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31232673

RESUMEN

A growing interest in developing and commercialization of new eco-friendly plastic polymers is occurring attributed to the impact of marine plastics debris and microplastics that result from the degradation of oil-based polymers as these substances adversely affect ecosystem health. Recently, polyhydroxybutyrate (PHB) has become of interest due to its biodegradability and physicochemical properties. However, biological consequences resulting from bioplastics exposure remain to be determined. Further, few data are apparently available regarding the potential for bioplastics to act as a vector for exogenous chemicals in the environment. The aim of the study was to compare the effects of polyethylene (PE MPs) and polyhydroxybutyrate (PHB MPs) microplastics administered alone or in combination with fluoranthene (Flu) on detoxifying enzymes in digestive glands and gills of Mytilus edulis. Blue mussels were exposed for 96h to eight experimental groups: control, Flu-only, PE MPs-only, PHB MPs-only, PE MPs-Flu co-exposure, PHB MPs-Flu co-exposure, Flu-incubated PE MPs, and Flu-incubated PHB MPs. Activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidases (GPx), glutathione S-transferase (GST), and glutathione reductase (GR) were found to be significantly susceptible to Flu and plastics in both tissues. Interestingly, a single exposure to PHB MPs led to decreased activity levels of CAT and GST in gills, SOD in digestive glands and SeGPx in both tissues. In co-exposure and incubation treatments, biochemical responses were generally comparable with those exerted by PE MPs or PHB MPs only, suggesting an apparent absence of combined effects of microplastics with the pollutant. Data demonstrated the ecotoxicological impact of bioplastics materials on digestive glands and gills of Mytilus edulis.


Asunto(s)
Fluorenos/toxicidad , Microplásticos/toxicidad , Mytilus edulis/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Poliésteres/toxicidad , Polietileno/toxicidad , Contaminantes Químicos del Agua/toxicidad , Animales , Biomarcadores , Dinamarca , Sistema Digestivo/efectos de los fármacos , Exposición a Riesgos Ambientales/efectos adversos , Branquias/efectos de los fármacos , Océanos y Mares
5.
J Toxicol Environ Health A ; 81(16): 761-773, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29969377

RESUMEN

The 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.


Asunto(s)
Fluorenos/toxicidad , Mytilus edulis/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Polietileno/toxicidad , Contaminantes Químicos del Agua/toxicidad , Animales , Relación Dosis-Respuesta a Droga
8.
J Toxicol Environ Health A ; 80(23-24): 1369-1371, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29131715

RESUMEN

Microplastics (MP) are contaminants of environmental concern partly due to plastics ability to sorb and transport hydrophobic organic contaminants (HOC). The importance of this "vector effect" is currently being debated in the scientific community. This debate largely ignores that the co-exposures of MP and HOC are mixtures of hazardous agents, which can be addressed from a mixture toxicity perspective. In this study, mixture effects of polyethylene microbeads (MP) and triclosan (TCS) (a commonly used antibacterial agent in cosmetics) were assessed on the marine copepod Acartia tonsa. Data indicated that MP potentiate the toxicity of TCS, illustrating the importance of understanding the mixture interaction between plastics and HOC when addressing the environmental importance of the vector effect.


Asunto(s)
Copépodos/efectos de los fármacos , Polietileno/toxicidad , Triclosán/toxicidad , Contaminantes Químicos del Agua/toxicidad , Animales , Antibacterianos/toxicidad , Sinergismo Farmacológico , Microesferas
9.
J Toxicol Environ Health A ; 78(6): 369-80, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25734764

RESUMEN

Assessment of genotoxic properties of chemicals is mainly conducted only for single chemicals, without taking mixture genotoxic effects into consideration. The current study assessed mixture effects of the three known genotoxic chemicals, 2,4-dichlorophenoxyacetic acid (2,4-D), acrylamide (AA), and maleic hydrazide (MH), in an experiment with a fixed ratio design setup. The genotoxic effects were assessed with the single-cell gel electrophoresis assay (comet assay) for both single chemicals and the ternary mixture. The concentration ranges used were 0-1.4, 0-20, and 0-37.7 mM for 2,4-D, AA, and MH, respectively. Mixture toxicity was tested with a fixed ratio design at a 10:23:77% ratio for 2.4-D:AA:MH. Results indicated that the three chemicals yielded a synergistic mixture effect. It is not clear which mechanisms are responsible for this interaction. A few possible interactions are discussed, but further investigations including in vivo studies are needed to clarify how important these more-than-additive effects are for risk assessment.


Asunto(s)
Ácido 2,4-Diclorofenoxiacético/toxicidad , Acrilamida/toxicidad , Daño del ADN , ADN/efectos de los fármacos , Contaminantes Ambientales/toxicidad , Hidrazida Maleica/toxicidad , Células CACO-2 , Ensayo Cometa , Herbicidas/toxicidad , Humanos , Reguladores del Crecimiento de las Plantas/toxicidad
10.
Environ Toxicol Pharmacol ; 107: 104411, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38452961

RESUMEN

This study investigates the presence of microplastics (MPs) in hypertonic fluid solutions, a widely used medical treatment packaged predominantly in plastic. For this purpose, in this study, 13 hypertonic fluid samples from different brands and two different types of packaging (polypropylene and polyvinyl chloride) were analyzed using visual particle counting, µ-Raman microscopy and ATR-FTIR. The results reveal the pervasive presence of MPs in all samples, with an estimated average concentration of 62.82 ± 72.38 MPs/1000 mL. There was no statistically significant difference in MP concentration between PP and PVC packaging. The particles predominantly consisted of fragments (74.1%) and fibers (25.9%), ranging in size from 0.04 to 2.37 mm. µ-Raman analysis identified 12 synthetic polymers as well as cellulose, with polyethylene and cellulose being the most prevalent. In conclusion, this study underscores the alarming presence of MPs in hypertonic fluid solutions, raising concerns about potential health risks.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Humanos , Plásticos , Monitoreo del Ambiente , Contaminantes Químicos del Agua/análisis , Celulosa
11.
Sci Total Environ ; 946: 174000, 2024 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-38901589

RESUMEN

Plastic overproduction and the resulting increase in consumption has made plastic pollution ubiquitous in all ecosystems. Recognizing this, the United Nations (UN) has started negotiations to establish a global treaty to end plastic pollution, especially in the marine environment. The basis of the treaty has been formulated in terms of turning off the tap, signaling the will to prevent plastic pollution at its source. Based on the distribution of plastic production by sector, the plastic packaging sector consumes the most plastic. The volume and variety of chemicals used in plastic packaging, most of which is single-use, is a major concern. Single-use plastics including packaging is one of the most dominant sources of plastic pollution. Plastic waste causes pollution in water, air and soil by releasing harmful chemicals into the environment and can also lead to exposure through contamination of food with micro- and nano-plastic particles and chemicals through packaging. Marine life and humans alike face risks from plastic uptake through bioaccumulation and biomagnification. While the contribution of plastics ingested to chemical pollution is relatively minor in comparison to other pathways of exposure, the effect of plastic waste on marine life and human consumption of seafood is beyond question. To reduce the long-term impact of plastic, it is crucial to establish a global legally binding instrument to ensure the implementation of upstream rather than downstream solutions. This will help to mitigate the impact of both chemicals and microplastics, including from packaging, on the environment.


Asunto(s)
Microplásticos , Plásticos , Contaminantes Químicos del Agua , Microplásticos/análisis , Plásticos/análisis , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente , Medición de Riesgo , Humanos
12.
Sci Total Environ ; : 174881, 2024 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-39047828

RESUMEN

The ubiquitous and global ecological footprint arising from the rapidly increasing rates of plastic production, use, and release into the environment is an important modern environmental issue. Of increasing concern are the risks associated with at least 16,000 chemicals present in plastics, some of which are known to be toxic, and which may leach out both during use and once exposed to environmental conditions, leading to environmental and human exposure. In response, the United Nations member states agreed to establish an international legally binding instrument on plastic pollution, the global plastics treaty. The resolution acknowledges that the treaty should prevent plastic pollution and its related impacts, that effective prevention requires consideration of the transboundary nature of plastic production, use and pollution, and that the full life cycle of plastics must be addressed. As a group of scientific experts and members of the Scientists' Coalition for an Effective Plastics Treaty, we concur that there are six essential "pillars" necessary to truly reduce plastic pollution and allow for chemical detoxification across the full life cycle of plastics. These include a plastic chemical reduction and simplification, safe and sustainable design of plastic chemicals, incentives for change, holistic approaches for alternatives, just transition and equitable interventions, and centering human rights. There is a critical need for scientifically informed and globally harmonized information, transparency, and traceability criteria to protect the environment and public health. The right to a clean, healthy, and sustainable environment must be upheld, and thus it is crucial that scientists, industry, and policy makers work in concert to create a future free from hazardous plastic contamination.

13.
J Toxicol Environ Health A ; 76(20): 1129-37, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24279814

RESUMEN

The aim of this study was to optimize the epithelioma papillosum cyprini (EPC) cell line handling procedure for the comet assay to investigate the genotoxic potential of widely used pesticides. The effects of various media and handling of the EPC cell line were examined. Results indicated that avoiding trypsin to detach cells led to lower level of DNA damage in the negative control. Further, two commonly used herbicides (Dezormon and Optica trio) and their four active ingredients (4-chloro-o-tolyloxyacetic acid, 2,4-dichlorophenoxyacetic acid, 2-(4-chloro-2-methylphenoxy)propionic acid, 2-(2,4-dichlorophenoxy)propionic acid) individually and in a ternary mixture were examined with the comet assay. Data showed that among the active ingredients only 2,4-D and MCPA induced DNA damage, while both herbicides were genotoxic at high concentrations.


Asunto(s)
Carpas/genética , Ensayo Cometa/métodos , Daño del ADN/genética , Monitoreo del Ambiente/métodos , Herbicidas/toxicidad , Contaminantes Químicos del Agua/toxicidad , Ácido 2,4-Diclorofenoxiacético/análogos & derivados , Ácido 2,4-Diclorofenoxiacético/toxicidad , Ácido 2-Metil-4-clorofenoxiacético/análogos & derivados , Ácido 2-Metil-4-clorofenoxiacético/toxicidad , Animales , Carcinoma/genética , Línea Celular
14.
Sci Total Environ ; 896: 165153, 2023 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-37385492

RESUMEN

The textile industry's business model is currently unsustainable and systemic changes must be made. The transition to a circular textile economy can be a major lever for this. However, it faces multiple issues, including the (in)ability of current legislations to provide sufficient protection regarding hazardous chemicals in recirculating materials. It is therefore crucial to identify legislative gaps that prevent the implementation of a safe circular textile economy, and to identify which chemicals could jeopardize this process. With this study, we aim to identify hazardous substances that could be found in recirculated textiles, to identify and discuss gaps in current regulations covering chemicals in textiles, and to suggest solutions to ensure better safety of circular textiles. We compile and analyze data on 715 chemicals and their associated functions, textile production stage, and hazard data. We also present how chemicals have been regulated over time and discuss regulations' strengths and weaknesses in the perspective of circular economy. We finally discuss the recently proposed Ecodesign regulation, and which key point should be included in the future delegated acts. We found that most of the compiled chemicals present at least one recognized or suspected hazard. Among them, there were 228 CMR (carcinogenic, mutagenic, reprotoxic substances), 25 endocrine disruptors, 322 skin allergens or sensitizers, and 51 respiratory allergens or sensitizers. 30 chemicals completely or partially lack hazard data. 41 chemicals were found to present a risk for consumers, among which 15 recognized or suspected CMR and 36 recognized or suspected allergens/sensitizers. Following the analysis of regulations, we argue that an improved risk assessment of chemicals should consider chemicals specific hazardous properties and product's multiple life cycles, instead of being limited to the product's end-of-life stage. We especially argue that implementing a safe circular textile economy requires that chemicals of concern are eliminated from the market.


Asunto(s)
Sustancias Peligrosas , Textiles , Unión Europea , Políticas , Alérgenos
15.
Sci Total Environ ; 865: 161255, 2023 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-36596418

RESUMEN

Microplastics (MPs) were quantified in Danish marine waters of the Kattegat and the southernmost part of Skagerrak bordering to it. Kattegat is a waterbody between Denmark and Sweden that receives inflow from the Baltic Sea and direct urban runoff from the metropolitan area of Copenhagen and Malmö. MPs were measured in 14 continuous transects while steaming between monitoring stations. MP levels tended to be highest close to the Copenhagen-Malmö area, albeit this was more obvious from the abundance of particles rather than mass. The outcome of the measurements allowed a rough MP budget in the Danish Straits region, suggesting that urban waste- and stormwater discharges could not be neglected as potential MP source in these waters. The marine samples were collected by pumping and filtering water over 10 µm steel filters, hereby sampling a total of 19.3 m3. They were prepared and analyzed by FPA-µFTIR imaging, and the scans interpreted to yield MP size, shape, polymer type, and estimated mass. The average concentration was 103 ± 86 items m-3, corresponding to 23.3 ± 28.3 µg m-3 (17-286 items m-3; 0.6-84.1 µg m-3). Most MPs were smaller than 100 µm and fragments dominated the samples. The carbonyl index was assessed for polyolefins, showing that oxidation increased with decreasing MP size, but did not correlate with distance to urban areas. A rough budget of MP in the Danish Straits region suggested that MPs discharged from urban waste- and stormwaters were an import source of MPs.

16.
Microplast nanoplast ; 3(1): 3, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36748026

RESUMEN

The intensive global plastic production, use and associated plastic pollution have caused concern for the potential risks to human health and the environment. This has led to the adoption of numerous regulatory initiatives aiming to combat plastic pollution. Despite the considerable regulatory activity in the field of plastic, it appears that there is still debate about the actual risks of plastic to humans and the environment. This raises the question of to what extent the current plastic regulation is evidence-based, a declared ambition in the European Union. Therefore, the aim of this study was to investigate to what extent key policy initiatives targeting plastic pollution are based on scientific evidence. Selection of initiatives was based on expert elicitation accounting for the opinions of persons involved in the development of the policy initiatives, and a thorough assessment of the historical development of plastic pollution regulation, with focus on their importance both with respect to regulation of plastics as well as their historical importance as drivers for societal actions on plastic pollution. We find that scientific evidence appears to be generally present in the scientific foundation for the policy initiatives analysed in this study. All the initiatives are supported by scientific articles and reports about among others plastic sources, ecological impacts of plastic production and consumption patterns. Marine litter monitoring data was found to contribute to the evidence base for 4 out of the 6 policy initiatives and thereby appears to be one of the central scientific drivers behind the societal actions on plastic pollution. Other scientific tools applied when shaping the policy initiatives include risk assessment, impact assessment and life cycle assessment. Despite the prevalent consideration and application of scientific evidence, there seems to be a broad recognition in the preparatory work of the initiatives that there is still a lot of uncertainty related to determining the harm of plastic pollution. In these cases, taking precautionary actions seems however to be justified, recalling not least the precautionary principle. As the issue of plastic pollution is complex and still subject to uncertainty, it seems important both that policy initiatives allow for flexibility and continuing adjustment to the on-going knowledge generation and that the scientific community provides the needed research to continue the science-informed policy development.

17.
Sci Total Environ ; 865: 161256, 2023 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-36587695

RESUMEN

Cigarette filters offer no public health benefits, are single-use plastics (cellulose acetate) and are routinely littered. Filters account for a significant proportion of plastic litter worldwide, requiring considerable public funds to remove, and are a source of microplastics. Used cigarette filters can leech toxic chemicals and pose an ecological risk to both terrestrial and aquatic ecosystems. Bottom-up measures, such as focusing on consumer behaviour, are ineffective and we need to impose top-down solutions (i.e., bans) if we are to reduce the prevalence of this number one litter item. Banning filters offers numerous ecological, socioeconomic, and public health benefits.


Asunto(s)
Fumar , Productos de Tabaco , Ecosistema , Plásticos , Salud Pública , Monitoreo del Ambiente
18.
Data Brief ; 51: 109740, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37965607

RESUMEN

Plastics are produced with a staggering array of chemical compounds, with many being known to possess hazardous properties, and others lacking comprehensive hazard data. Furthermore, non-intentionally added substances can contaminate plastics at various stages of their lifecycle, resulting in recycled materials containing an unknown number of chemical compounds at unknown concentrations. While some national and regional regulations exist for permissible concentrations of hazardous chemicals in specific plastic products, less than 1 % of plastics chemicals are subject to international regulation [1]. There are currently no policies mandating transparent reporting of chemicals throughout the plastics value chain or comprehensive monitoring of chemicals in recycled materials. The dataset presented here provides the chemical analysis of 28 samples of recycled High-Density Polyethylene (HDPE) pellets obtained from various regions of the Global South, along with a reference sample of virgin HDPE. The analysis comprises both Target and Non-Targeted Screening approaches, employing Liquid Chromatography-High-Resolution Mass Spectrometry (LC-HRMS) and Gas Chromatography-High-Resolution Mass Spectrometry (GC-HRMS). In total, 491 organic compounds were detected and quantified, with an additional 170 compounds tentatively annotated. These compounds span various classes, including pesticides, pharmaceuticals, industrial chemicals, plastic additives. The results highlight the prevalence of certain chemicals, such as N-ethyl-o-Toluesulfonamide, commonly used in HDPE processing, found in high concentrations. The paper provides a dataset advancing knowledge of the complex chemical composition associated with recycled plastics.

20.
Sci Total Environ ; 806(Pt 4): 150914, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-34653473

RESUMEN

Research suggests that behavior change programs can be fast and cost-effective solutions to plastic pollution alongside traditional environmental policy-making. Furthermore, encouraging change in perception and behavior can be a tool to change consumption and waste handling towards increased circularity, which is of high concern in the EU. Beyond knowledge, predictors of pro-environmental behavior include concern, social norms, nature-connectedness, identity and self-efficacy. Citizen Science (CS) as a way to raise awareness and potentially change behavior show promise within plastic litter monitoring. We tested the feasibility of evaluating a nation-wide citizen science intervention, 'the Mass Experiment' (ME), with school students (age 7-16) in Denmark. With more than 57,000 students signed up for ME, this is to our knowledge one of the largest CS activity on plastic debris targeting young people. As an addition to the core CS activity we developed a voluntary and anonymous questionnaire to study the perceptions and behaviors of the students. We hypothesized that the intervention would increase risk perception, self-efficacy and empowerment as well as self-reported actions. Through 931 pre-surveys and 838 post-surveys aggregated at the team level (n = 48), we found that the intervention had no significant overall effect on team, risk-perception, pro-environmental behaviors, nor self-efficacy or empowerment. However, unexpected patterns emerged for age effects, potentially advising some caution over the design of such CS activities particularly for younger children. We discuss methodological limitations, the high baseline for nearly all variables, the Danish context and the intervention itself and make recommendations for studying future CS interventions.


Asunto(s)
Contaminación Ambiental , Plásticos , Adolescente , Niño , Dinamarca , Estudios de Factibilidad , Humanos , Encuestas y Cuestionarios
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