Global producer responsibility for plastic pollution.

Brand names can be used to hold plastic companies accountable for their items found polluting the environment. We used data from a 5-year (2018-2022) worldwide (84 countries) program to identify brands found on plastic items in the environment through 1576 audit events. We found that 50% of items were unbranded, calling for mandated producer reporting. The top five brands globally were The Coca-Cola Company (11%), PepsiCo (5%), Nestlé (3%), Danone (3%), and Altria (2%), accounting for 24% of the total branded count, and 56 companies accounted for more than 50%. There was a clear and strong log-log linear relationship production (%) = pollution (%) between companies' annual production of plastic and their branded plastic pollution, with food and beverage companies being disproportionately large polluters. Phasing out single-use and short-lived plastic products by the largest polluters would greatly reduce global plastic pollution.

Microplastic contamination in filter-feeding oyster Saccostrea cuccullata: Novel insights in a marine ecosystem.

Microplastic (MP) pollution has become a pressing global concern. Oysters are well-known filter feeders who ingest food by filtering microscopic particles suspended in the surrounding water. Along with organic matter, filter-feeding also causes accidental ingestion of MP by oysters. Hence, the aim of the current investigation is to understand the MP contamination in filter-feeding oysters. A total of 500 specimens of oyster Saccostrea cuccullata collected from the intertidal zone of five sampling locations on the Gujarat coast, India. Specimens underwent analysis following established protocols. Each specimen was found to exhibit MP contamination, showing an abundance of 2.72 ± 1.98 MPs/g. A negative relationship was found between shell length and MP abundance. Predominantly, fibers were documented across all study sites. Black, blue, and red-colored MPs with 1-2 mm sizes were most dominant. MP polymer composition was identified as polyethylene terephthalate and polypropylene. Findings provide baseline information on levels of MPs contamination, which can be used to monitor future effects of MP pollution.

Corrigendum to "Phytochemicals and bioactive constituents in food packaging - A systematic review" [Heliyon 9(11) (November 2023) e21196].

[This corrects the article DOI: 10.1016/j.heliyon.2023.e21196.].

Assessing spatial impacts of historical pulp mill effluent on trophic dynamics in a coastal marine ecosystem using stable isotope (δ13C and δ15N) analysis.

Boat Harbour, Nova Scotia was a tidal estuary that was converted into a wastewater treatment facility for pulp mill effluent in 1967. Treated effluent from Boat Harbour was discharged into the coastal Northumberland Strait, contributing significant nutrient and freshwater inputs into the coastal environment, potentially impacting local biogeochemistry and ecosystem structure. This study used stable isotope analysis of carbon (δ13C) and nitrogen (δ15N) of representative taxa to assess spatial variability in nutrient sources and trophic dynamics. Results identified stable isotope variation with depleted δ13C and δ15N values in taxa near Boat Harbour. Blue mussel (Mytilus edulis) and mummichog (Fundulus heteroclitus) were the most suitable bioindicators for identifying variation in nutrient sources. Stable isotope signatures in this study may be reflective of residual pulp mill effluent-derived nutrients, differences in marine versus terrestrial nutrient sources, and a pronounced coastal salinity gradient. The present study defined the baseline nutrient conditions of the Northumberland Strait and will be useful in assessing the effectiveness of remediation activities.

Phytochemicals and bioactive constituents in food packaging - A systematic review.

Designing and manufacturing functional bioactive ingredients and pharmaceuticals have grown worldwide. Consumers demand for safe ingredients and concerns over harmful synthetic additives have prompted food manufacturers to seek safer and sustainable alternative solutions. In recent years the preference by consumers to natural bioactive agents over synthetic compounds increased exponentially, and consequently, naturally derived phytochemicals and bioactive compounds, with antimicrobial and antioxidant properties, becoming essential in food packaging field. In response to societal needs, packaging needs to be developed based on sustainable manufacturing practices, marketing strategies, consumer behaviour, environmental concerns, and the emergence of new technologies, particularly bio- and nanotechnology. This critical systematic review assessed the role of antioxidant and antimicrobial compounds from natural resources in food packaging and consumer behaviour patterns in relation to phytochemical and biologically active substances used in the development of food packaging. The use of phytochemicals and bioactive compounds inside packaging materials used in food industry could generate unpleasant odours derived from the diffusion of the most volatile compounds from the packaging material to the food and food environment. These consumer concerns must be addressed to understand minimum concentrations that will not affect consumer sensory and aroma negative perceptions. The research articles were carefully chosen and selected by following the Preferred Reporting Items for Systematic Reviews (PRISMA) guidelines.

Assessing the impact of chronic and acute plastic pollution from construction activities and other anthropogenic sources: A case study from the coast of Antofagasta, Chile.

Plastic pollution is a critical environmental issue with far-reaching and not yet fully explored consequences. This study uncovered a significant source of plastic contamination arising from improper application and management of expanded polystyrene (EPS) utilised as expansion joints at a construction site near the coast of Antofagasta, Chile. Through meticulous field observations and calculations, we estimate that a staggering 82.9 million EPS spheres have the potential to be released into the environment from the 7.62 m3 of this material used for the construction of this coastal promenade, constituting a chronic source of pollution. Despite the ongoing construction, we have already evidenced mechanical fragmentation and dispersion of EPS microplastic pollution in the surrounding natural environment. To our knowledge, this is the first study that documents misused construction materials contributing to plastic pollution. In addition to the EPS pollution, our findings reveal an alarming accumulation of litter - an acute pollution source - including plastic cups, bottles, carrier bags, and several other construction materials (e.g. plastic nets, films) that are exacerbating the pollution problems within the region and potentially endangering marine and terrestrial organisms. These observations highlight the urgent need for mitigating measures and intervention policies targeting construction-related plastic and microplastic pollution, along with a more robust regulatory framework for construction activities as well as adequate surveillance and enforcement.

Cleaning Up without Messing Up: Maximizing the Benefits of Plastic Clean-Up Technologies through New Regulatory Approaches.

As the global plastics crisis grows, numerous technologies have been invented and implemented to recover plastic pollution from the environment. Although laudable, unregulated clean-up technologies may be inefficient and have unintended negative consequences on ecosystems, for example, through bycatch or removal of organic matter important for ecosystem functions. Despite these concerns, plastic clean-up technologies can play an important role in reducing litter in the environment. As the United Nations Environment Assembly is moving toward an international, legally binding treaty to address plastic pollution by 2024, the implementation of plastic clean-up technologies should be regulated to secure their net benefits and avoid unintended damages. Regulation can require environmental impact assessments and life cycle analysis to be conducted predeployment on a case-by-case basis to determine their effectiveness and impact and secure environmentally sound management. During operations catch-efficiency and bycatch of nonlitter items, as well as waste management of recovered litter, should be documented. Data collection for monitoring, research, and outreach to mitigate plastic pollution is recommended as added value of implementation of clean-up technologies.

Risk assessment of sediment PAH, BTEX, and emerging contaminants in Chanomi Creek Niger Delta, Nigeria.

This study assessed the levels of polycyclic aromatic hydrocarbons (PAHs), benzene, toluene, ethylbenzene, and xylene (BTEX), and emerging contaminants in Chanomi Creek. Sediment samples were collected between March 2019 and July 2020 to evaluate the concentrations of PAH, BTEX, and emerging contaminants using GC-MS and GC-FID with Headspace extraction. Results indicated mean PAH concentrations were 22.691 ± 15.09 µg/kg. The highest individual PAH concentrations were fluorene (7.085 µg/kg), naphthalene (4.517 µg/kg), and phenanthrene (3.081 µg/kg). Carbazole (0.828 µg/kg) was discovered as a novel environmental toxin with dioxin-like toxicity and widespread prevalence in sediments. The most common congener (25%) was ethylbenzene, followed by toluene and ortho- and meta-xylene (21%) and benzene (13%). The analysis of diagnostic ratios revealed that the main factors responsible for the presence of PAHs in the study area are the residential use of firewood, emissions from industrial activities, bush burning, and petroleum slicks. The risk assessment indicated that most PAHs exceeded the permissible risk quotient values, suggesting a moderate to high ecological risk. However, cutaneous exposure to PAHs and BTEX was found to have minimal impact on human health, with no significant hazards identified in adults and children. Nevertheless, the study revealed low cancer risks associated with PAH and BTEX compounds for both age groups. The continued discharge of PAHs and BTEX compounds into Chanomi Creek could have significant long-term negative effects on human and aquatic health. Thus, contamination risk awareness programs and the development of stringent contextual thresholds for identified contaminants could enhance environmental and public health protection.

Eco-Friendly Green Synthesis and Characterization of Silver Nanoparticles by Scutellaria multicaulis Leaf Extract and Its Biological Activities.

Scutellaria multicaulis is a medicinal plant indigenous to Iran, Afghanistan, and Pakistan. It has been widely used as a prominent herb in traditional medicine for thousands of years. This plant is reported to contain baicalein, wogonin, and chrysin flavonoids, which are a significant group of chemical ingredients which can cure different diseases, such as breast cancer. S. multicaulis leaf extract was used for the bioreduction of silver nanoparticles (SmL-Ag-NPs), and their phytochemical contents and antioxidant, antibacterial, anti-proliferative, and apoptotic activity were evaluated. Optimal physicochemical properties of SmL-Ag-NPs were obtained by mixing 5% of leaf extract and 2 mM of aqueous AgNO3 solution and confirmed by characterization studies including UV-visible spectrophotometry, Field Emission Scanning Electron Microscope (FE-SEM), Energy Dispersive X-ray (EDX), Dynamic Light Scattering (DLS), zeta potential, Thermogravimetric analysis (TGA), Surface-enhanced Raman spectroscopy (SERS), X-ray crystallography (XRD), and Fourier transform infrared (FTIR) Spectroscopy. SmL-Ag-NPs exhibited a higher content of total phenol and total flavonoid and potential antioxidant activity. SmL-Ag-NPs also demonstrated dose-dependent cytotoxicity against MDA-MB231 cell multiplication with an IC50 value of 37.62 µg/mL through inducing cell apoptosis. Results show that SmL-Ag-NPs is effective at inhibiting the proliferation of MDA-MB231 cells compared to tamoxifen. This demonstrates that SmL-Ag-NPs could be a bio-friendly and safe strategy to develop new cancer therapies with a reduction in the adverse effects of chemotherapy in the near future.

Metal and metalloid bioaccumulation in dried red seaweed Hypnea musciformis and health risk assessment for consumers.

This study measured 22 metal and metalloid concentrations in Hypnea musciformis from the Bakkhali River estuary and Saint Martin's Island, Bangladesh and determined their potential impact on consumption. Student t-tests showed a significant variation in metal concentrations between the two sampling sites (p < 0.05). Mean concentrations of Co (2.49 ± 0.05 mg/kg), Fe (793.29 ± 11.76 mg/kg), Mn (368.72 ± 4.87 mg/kg), Pb (3.82 ± 0.02 mg/kg), V (11.23 ± 0.20 mg/kg) and Zn (16.60 ± 0.28 mg/kg) were higher in samples collected from the Bakkhali River estuary compared to Saint Martin's Island, while mean concentrations of Ca (484.18 ± 4.68 mg/kg), Cd (2.44 ± 0.03 mg/kg), Mg (2112.70 ± 17.80 mg/kg), Mo (1.57 ± 0.06 mg/kg), Sr (2377.57 ± 29.98 mg/kg), and Ti (258.27 ± 4.62 mg/kg) were higher in samples collected from Saint Martin's Island. Eight heavy metals (Pb, Cd, Zn, Cu, Ni, Mn, Cr, Fe) were used to assess potential health risks for adults, but no potential health risk was detected (HQ value>1). This study reveals positive Se-HBV for H. musciformis collected from both sampling sites, indicating no potential risks involved with Hg toxicity.

What not to do with dog poop.

This short communication paper comments on the controversial but highly unpleasant topic of littered plastic dog waste bags in the environment. Littered plastic dog waste bags are a source of plastic and microplastic pollution and dog faeces contained in these littered bags also pose human and ecological health risks. This short communication suggests that this littering may be occurring due to confusion by pet owners, who may believe that these so called 'biodegradable' bags are compositable, which in the absence of industrial composting facilities, are not. Thus, plastic dog waste bags continue to be a source of plastic and microplastic pollution in the environment long after they have been littered. All pet owners should deposit plastic dog poop bags in appropriate waste bins, not in the environment.

Acute toxicity of triclosan, caffeine, nanoplastics, microplastics, and their mixtures on Daphnia magna.

We measured acute toxicity of triclosan, caffeine, nanoplastics, and microplastics, and their mixtures on Daphnia magna. Limitations of this study included use of a single species, acute rather than chronic toxicity testing, examination of single substances and their mixtures, and laboratory conditions that may not reflect real-world scenarios. Single compound toxicity results revealed a clear concentration-response pattern, with triclosan showing higher toxicity than caffeine, and nanoplastics displaying higher toxicity than microplastics. Combinations of triclosan with nanoplastics, and microplastics resulted in varying mortality rates, with higher rates observed with increased concentrations of triclosan and nanoplastics. Similar results were observed with caffeine, nanoplastics, and microplastics mixtures. These findings underline potential hazards posed by these pollutants to marine ecosystems and highlight the need for further studies to understand chronic effects, interactive effects of multiple substances, and the impact under more environmentally relevant conditions.

Identifying opportunities for harmonized microplastics and mesoplastics monitoring for Caribbean Small Island Developing States using a spatiotemporal assessment of beaches in South Eleuthera, The Bahamas.

Increasing quantities of microplastics and mesoplastics in the marine environment underscore the need for marine microplastics to be included in the global Plastics Treaty to end plastic pollution. Caribbean Small Island Developing States (SIDS) lack harmonized microplastics monitoring protocols, leaving them data deficient at the science-policy interface required for treaty negotiations. This baseline study assessed spatial and seasonal abundance and distribution of microplastic (1-5 mm) and mesoplastic (5-25 mm) on 16 beaches with three coastal exposures (Atlantic Ocean, Exuma Sound, Bahama Bank) in South Eleuthera, The Bahamas and its implications for Caribbean SIDS. Microplastics were the dominant debris type sampled (74 %) across all beaches, with significant spatial (p = 0.0005) and seasonal (p = 0.0363) differences in abundance and distribution across study sites. This baseline study identifies opportunities required for developing harmonized microplastics and mesoplastics monitoring by Caribbean SIDS to collect data to help support global plastics treaty negotiations.

Environmental and economic impacts of retrieved abandoned, lost, and discarded fishing gear in Southwest Nova Scotia, Canada.

Abandoned, lost, and discarded fishing gear (ALDFG), negatively impacts marine environments. Managing ALDFG in Atlantic Canada is challenging due to knowledge gaps on loss rates, locations, data availability/accuracy, impacts, and regulatory barriers for retrieval. This study removed ALDFG in Southwest Nova Scotia in collaboration with local fishers (with local knowledge and practical ALDFG removal expertise), government, non-profit organizations, and academia. A total of 29,298 kg of ALDFG was retrieved, including 24,630 kg using towed grapples covering ~3986 km of seafloor and 4668 kg from shorelines (comprising, 68 % lobster traps and 12 % dragger cable by weight). Traps ranged from <1 to 37 years old (median, 10 years). Traps continued to catch target and non-target species with 25 species released, including 652 individual lobsters (82 % were market-sized) and 57 fish (42 were species-at-risk). Based on estimated 2 % trap losses, annual commercial losses from ALDFG were $155,836 CAD in Lobster Fishing Area 34.

Spatiotemporal trends and characteristics of microplastic contamination in a large river-dominated estuary.

Microplastic (MP) pollution is a major global issue that poses serious threats to aquatic organisms. Although research on MP pollution has been extensive, the relationship between MPs and water quality parameters in estuarine water systems is unclear. This work studied the spatiotemporal distribution and characteristics of MPs in the Karnaphuli River estuary, Bangladesh. MP abundance was calculated by towing with a plankton net (300 µm mesh size) at three river gradients (up-, mid- and downstream) and the association between physicochemical parameters of water (temperature, pH, salinity, electrical conductivity, total dissolved solids, and dissolved oxygen) and MP distribution patterns was also investigated. Mean MP abundance in water was higher during the wet season (April) (4.33 ± 2.45 items per m3) compared to the dry season (September) (3.65 ± 2.54 items per m3). In descending order, the highest MP abundance was observed downstream (6.60 items per m3) > midstream (3.15 items per m3) > upstream (2.22 items per m3). pH during the wet season (April) and temperature during the dry season (September) were key physicochemical parameters that correlated with river MP abundance (r = -0.74 and 0.74 respectively). Indicating that if the Karnaphuli River water has low pH or high temperature, there is likely to be high MPs present in the water. Most MP particles were film-shaped, white in color, and 1-5 mm in size. Of the six polymers detected, polypropylene (PP), polystyrene (PS), polyethylene terephthalate (PET), and cellulose were predominant, comprising roughly 17-19% each. These results can be used to model MP transport in the freshwater ecosystem of the Karnaphuli River estuary in Bangladesh to help develop future mitigation strategies.

Baseline monitoring of contaminant concentrations in American lobster (Homarus americanus) tissues from coastal Northumberland Strait, Nova Scotia, Canada.

A baseline survey was conducted in 2018 to characterize contaminants in American lobsters, Homarus americanus in the Northumberland Strait, Canada. Sampling included three age classes of lobsters at sites 4, 20, and 70 km from the Boat Harbour estuary, a historically contaminated site set to undergo remediation. Lobster tissues were measured for metal(loids), methylmercury, polycyclic aromatic hydrocarbons, and polychlorinated dibenzo-p-dioxins and polychlorinated dibenzo-p-furans. Contaminant concentrations were generally below the guidelines set by the Canadian Council of Ministers of the Environment and the Canadian Food Inspection Agency, except for arsenic which was elevated in all age classes from all sites (4.8-12.68 mg kg-1). Mercury and methylmercury (both ~0.04 mg kg-1) minimally exceeded one guideline in some age-classes and sites. There was also no consistent pattern of contaminant accumulation across either age classes or at particular sites. This study serves as a baseline for future monitoring following remediation of Boat Harbour.

Time to kick the butt of the most common litter item in the world: Ban cigarette filters.

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.

Comparative analysis of the contribution of municipal waste management policies to GHG reductions in China.

Waste generation and disposal have been a global issue for decades. The total global greenhouse gas (GHG) emissions in 2019 were 49,758 MtCO2e with waste disposal accounting for 3.2%. With rapid urbanization trends, municipal solid waste (MSW) has become a global challenge which needs to be addressed. A large fraction of MSW such as food wastes, e-waste among others still ends up with unregulated dumps or openly burned in low-income countries. As a response, China initiated the 'zero-waste' pilot program which has been running since 2019. To investigate the potential contribution of MSW management to GHG reductions, this study selected four 'zero-waste' cities in China, namely Shenzhen, Panjin, Xining and Tongling, as case studies to assess the impacts of different MSW management policies on GHG reductions from 2015 to 2019. Results demonstrated that Shenzhen city achieved progress in reducing GHGs, which decreased by more than 40% between 2015 and 2019. This study provides policy recommendations and waste management approaches and practices to optimize MSW management and reduction of GHGs.