Tony Robert Walker

Dalhousie University | Dal · School for Resource and Environmental Studies

Marine plastic pollution has been a growing concern for decades. Single-use plastics (plastic bags and microbeads) are a significant source of this pollution. Although research outlining environmental, social, and economic impacts of marine plastic pollution is growing, few studies have examined policy and legislative tools to reduce plastic pollut...

Single-use plastics, or SUPs (plastic bags, microbeads, cutlery, straws and polystyrene) are substantial sources of plastic marine pollution, yet preventable via legislative and non-legislative interventions. Various international legislative strategies have been reported to address plastic marine pollution from plastic bags and microbeads, but the...

Plastics are essential in society as a widely available and inexpensive material. Mismanagement of personal protective equipment (PPE) during COVID-19 pandemic, with a monthly estimated use of 129 billion face masks and 65 billion gloves globally, is resulting in widespread environmental contamination. This poses a risk to public health as a vector...

Plastics have been on top of the political agenda in Europe and across the world to reduce plastic leakage and pollution. However, the COVID-19 pandemic has severely disrupted plastic reduction policies at the regional and national levels and induced disruptive changes in plastic waste management with potential for negative impacts in the environme...

Marine transportation drives global trade, moving over 10 billion tonnes of containers, solid and liquid bulk cargo across the world's seas annually. Historically, shipping companies and ports operated with limited environmental oversight, but accidental oil spills in the 1960s, caused widespread coastal pollution and seabird mortality, triggering...

Plastics have become an integral component in agricultural production as mulch films, nets, storage bins and in many other applications, but their widespread use has led to the accumulation of large quantities in soils. Rational use and reduction, collection, reuse, and innovative recycling are key measures to curb plastic pollution from agricultur...

Purpose of Review: Dietary consumption of prebiotics, probiotics, and synbiotics has been suggested to improve human health conditions. Functional food products containing live probiotics are flourishing, and their demand seems to be increasing since consumers are more aware of the health benefits of such products. However, specific food packaging...

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 Anto-fagasta, Chile. Th...

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 ecos...

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 extrac...

Toxicity of single pollutants or microplastics (MPs) on organisms have been widely reported. However, their combined toxicity with boron has not been investigated. This study examined effects of individual polypropylene microplastics (PP-MPs) or mixed PP-MPs and boron on biochemical biomarkers in red tilapia (Oreochromis niloticus). O. niloticus we...

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...

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,...

Abandoned, lost, or otherwise discarded fishing gear (ALDFG) has surfaced as a significant conservation issue that continues to compromise the economic, social, and ecological aspects of the marine environment. To alleviate these concerns, methods of lost gear detection at the seabed can be applied to increase the precision of derelict gear retriev...

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 sugge...

Plastic and microplastic pollution is a complex, muti-faceted challenge that has engaged a broad alliance of stakeholder groups who are concerned with environmental, biotic and human health [1]. The urgency surrounding this topic is evidenced by the ongoing negotiations regarding a global Plastics Treaty agreement [2,3]. The research area is rapidl...

Scutellaria multicaulis, a member of the Lamiaceae, 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 with baicalein, wogonin, and chrysin flavonoids as a significant group of chemical ingredients, which can cure diff...

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 in...

The atmosphere can transport large quantities of microplastics (MPs) and disperse them throughout the globe to locations inaccessible by many other transport mechanisms. Meteorological events, such as tropical cyclones, have been proven to pick up and transport particulate matter, however, how hurricanes influence the transport and deposition of at...

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. Sin...

n preparation for the second session of the intergovernmental negotiating committee in Paris, from 29 May to 2 June, the Global Plastics Policy Centre team of the University of Portsmouth, together with researchers from the Dalhousie University, Canada, unpacks a debated topic from the first round of negotiations in November 2022 – national action...

Plastics pollute all environmental compartments because of human activities and mismanagement. Public perceptions and knowledge about plastic pollution differ among individuals and across different jurisdictions. Targeted survey-based research tools can help measure consumer awareness about impacts of mismanaged plastics and help identify trends an...

In this Matters Arising, we respond to a recent article by Bachmann et al.1 We argue that dealing with plastics pollution as a novel entity within the planetary boundaries framework needs to consider the entirety of the plastics life cycle, from resource extraction to impacts on earth system processes. Singling out LCA quantifications to set a boun...

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 fisher...

Marine biofouling has been an issue since antiquity whose solutions have a history of negative environmental impact. The development of environmentally sustainable solutions is paramount as society is becoming more conscious of anthropogenic impacts on the global ecosystem, particularly the global oceans. Herein we include a brief overview of commo...

Three industrial facilities (a kraft pulp mill, a tire manufacturing, and a coal-fired power generation plant), have operated in Pictou County, Nova Scotia, Canada for more than 50 years. The local population, including an Indigenous community, has raised concerns for several decades about the environmental and human health impacts of local air and...

Fish and fish tissue are effective bioindicators due to their sensitivity to pollution and are frequently used for assessing aquatic ecosystem health. Establishing baseline metal concentrations in freshwater fish tissues within aquatic ecosystems is important prior to establishing industrial activities to help determine potential future industrial...

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 Riv...

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 me...

Book review of Erica Cirino, Thicker Than Water: The Quest for Solutions to the Plastic Crisis (Washington, Covelo: Island Press, 2021), 272 pp.

There are many studies considering the use and waste management of plastics but these are primarily focused on recycling. While studies of human interaction with plastics provide some insight into current waste creation and recycling choices, studies on behaviour change and the human relationship to plastic are limited. In this perspective, we pose...

Unsustainable plastic production, use and mismanagement has resulted in increased global plastic pollution and subsequent degradation into micro(nano)plastics in the environment threatening sustainability. Micro(nano) plastic pollution is pervasive and has caused widespread ecological impacts globally, including greenhouse gas emissions, contributi...

Unsustainable plastic production, use and mismanagement has resulted in increased plastic pollution in the environment threatening sustainability, especially in the tropics. Countries in the tropics have been disproportionally impacted by plastic pollution due to imports of plastic waste from developed countries, or because tropical Small Island De...

Marine litter colonization by marine invertebrate species is a major global concern resulting in the dispersal of potentially invasive species has been widely reported. However, there are still several methodological challenges and uncertainties in this field of research. In this review, literature related to field studies on marine litter coloniza...

We explored the waste generation and environmental perceptions of a group of participants (n=50) collecting their non-perishable waste for a social media campaign, Futuristic February, in 2020 pre-COVID. We also performed a mini-review on google and google scholar to inform areas commonly prone to misinformation or confusion on the topics of waste...

Microplastics are pervasive pollutants and have been found in all environmental compartments globally, including aquatic ecosystems. Ingestion and trophic transfer of microplastics through aquatic species have been widely reported. Although a plethora of studies have reported that microplastics can be transferred through higher trophic level food w...

The COVID-19 pandemic has induced some negative environmental issues, especially in the waste management sector. In developing countries, handling waste is carried out by two groups: waste workers and waste pickers who are exposed to possible hazards of infected waste. In the present narrative review, we searched for high-quality English publicatio...

Honey can be used to biomonitor contaminants, as honeybees can bioaccumulate both organic and inorganic (e.g., metal(loid)) contaminants from the total environment. Honey chemical composition can be influenced by natural and anthropogenic activities. Metal(loid) concentrations in honey samples collected by citizen scientist beekeepers in northwest...

In Canada, small craft harbors (SCHs) are a federal government responsibility under Fisheries and Oceans Canada (DFO). SCHs are economic centres for many rural coastal communities in Canada. By studying the role of SCHs on livelihoods one can delineate their importance to the users and community. The pilot study utilized semi-structured telephone i...

Both the aquaculture industry and eco-certification of aquaculture have grown significantly over the past 20 years, but the extent to which aquaculture eco-certification is effective in creating positive environmental and societal outcomes is uncertain. Therefore, a scoping review of research on the effectiveness of eco-certification in improving a...

Cigarette filters offer no public health benefits, are single-use plastics and the most common source of plastic (cellulose acetate) pollution. Filters are routinely littered, accounting for a significant proportion of plastic litter worldwide, requiring considerable public funds to remove, and are a source of microplastics. Used cigarette filters...

In March, the global community agreed to establish a legally binding treaty to end plastic pollution. To deliver on this goal, the treaty needs to cover all issues of plastics chemicals as an inseparable part of the problem.

Waste generation and disposal have been a global issue for decades. The total global greenhouse gas (GHG) emissions in 2019 were 49,758 MtCO 2 e 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,...

Marine litter colonization is widely investigated as an important pathway for the dispersal of potentially invasive species. However, this phenomenon may be impacting marine biota in other ways as well. In this viewpoint, we express our concerns regarding the potential loss of viable eggs of numerous oviparous fishes deposited on marine litter when...

Polycyclic aromatic hydrocarbon (PAH) contaminated agricultural soil is widespread globally. To develop a cost-effective remediation technique to effectively degrade PAH contaminated agricultural soil without disturbing crop production, an in-situ co-remediation of PAH contaminated agricultural soil using blood meal and celery was assessed in an ag...

The United States is threatening to undermine the United Nations Environment Assembly’s move to adopt a legally binding global agreement to curb plastic pollution by 2024 (Nature 603, 202; 2022). It seeks instead to form a coalition of countries to drive treaty negotiations.

Journal website link: www.frontiersin.org

Baseline marine litter abundance and distribution on Saint Martin Island, Bay of Bengal, were assessed. Seventy-two transects (100-150 m) along 12 km of coastline were surveyed for litter items every two weeks for two months. The most abundant items were polythene bags, food wrappers, plastic bottles/caps, straws, styrofoam, plastic cups, plastic f...