Tony R. Walker

International policies to reduce plastic marine pollution from single-use plastics (plastic bags and microbeads): A review

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 pollution, particularly single-use plastics (plastic bags and microbeads). This paper reviews current international market-based strategies and policies to reduce plastic bags and microbeads. While policies to reduce microbeads began in 2014, interventions for plastic bags began much earlier in 1991. However, few studies have documented or measured the effectiveness of these reduction strategies. Recommendations to further reduce single-use plastic marine pollution include: (i) research to evaluate effectiveness of bans and levies to ensure policies are having positive impacts on marine environments; and (ii) education and outreach to reduce consumption of plastic bags and microbeads at source.

Metal(loid)s in sediment, lobster and mussel tissues near historical gold mine sites

Previous studies near historical gold mining districts in Nova Scotia have identified significant enrichment of metal(loid)s in coastal marine sediments. Most of this inventory is buried below biologically active zones, although in some areas arsenic has bioaccumulated in marine biota resulting in localised bivalve shellfish closures. Isaacs Harbour is poised for future industrial development, but before potential impacts are predicted, current marine baseline conditions must be determined. To address this gap, this study established a baseline using surface sediments and biota (mussel and lobster tissues), to provide a broader picture of metal(loid)s in the marine environment. Results confirmed previous studies showing that most sediment metal(loid) concentrations still exceeded Canadian Marine Sediment Quality Guidelines, and also provided evidence of Canadian Food Inspection Agency fish tissue exceedances of arsenic in lobster and lead in mussel tissues indicating that some bioaccumulation of legacy contaminants in marine biota continues to the present day.

Assessment of public perception and environmental compliance at a pulp and paper facility: a Canadian case study

Communities across Canada rely heavily on natural resources for their livelihoods. One such community in Pictou County, Nova Scotia, has both benefited and suffered, because of its proximity to a pulp and paper mill (currently owned by Northern Pulp). Since production began in 1967, there have been increasing impacts to the local environment and human health. Environmental reports funded by the mill were reviewed and compared against provincial and federal regulatory compliance standards. Reports contrasted starkly to societal perceptions of local impacts and independent studies. Most environmental monitoring reports funded by the mill indicate some levels of compliance in atmospheric and effluent emissions, but when compliance targets were not met, there was a lack of regulatory enforcement. After decades of local pollution impacts and lack of environmental compliance, corporate social responsibility initiatives need implementing for the mill to maintain its social licence to operate.

Green Marine: An environmental program to establish sustainability in marine transportation.

European maritime companies have adopted programs to limit operational impacts on the environment. For maritime companies in North America, the Green Marine Environmental Program (GMEP) offers a framework to establish and reduce environmental footprints. Green Marine (GM) participants demonstrate annual improvements of specific environmental performance indicators (e.g., reductions in air pollution emissions) to maintain certification. Participants complete annual self-evaluations with results determining rankings for performance indicators on a 1-to-5 scale. Self-evaluations are independently verified every two years to ensure rigor and individual results are made publicly available annually to achieve transparency. GM benefits the marine industry across North America by encouraging sustainable development initiatives. GMs credibility is reflected through a diverse network of environmental groups and government agencies that endorse and help shape the program. Merits of this relatively new maritime certification (not previously described in the academic literature), are discussed.

Mercury concentrations in marine sediments near a former mercury cell chlor-alkali plant in eastern Canada

Concentrations of total mercury (THg) were measured in coastal marine sediments near a former chlor-alkali plant in Chaleur Bay, New Brunswick. The chlor-alkali plant has been a local point source of THg since operation began in 1963. Historical THg contamination of marine sediments and biota has been widely reported. No baseline assessment has been conducted following plant closure in 2008. Surface (0-2cm) oxidized marine sediments were sampled along a single 5.2km transect radiating from the former plant and analysed for THg. THg concentrations ranged from 0.04-0.28μgg(-1). Some localised THg concentrations exceeded Canadian marine sediment quality guidelines (n=4), but all samples (n=14) were significantly lower than previous studies conducted during plant operation. Plant closure (source control) and natural sediment recovery likely responsible for attenuating THg concentrations, but burial in deeper anoxic sediments may increase bioavilability of Hg that could pose ecological risks to marine biota.

Forensic assessment of polycyclic aromatic hydrocarbons at the former Sydney Tar Ponds and surrounding environment using fingerprint techniques

Polycyclic aromatic hydrocarbons (PAHs) were assessed spatially and temporally within and adjacent to a former coking and steel manufacturing facility in Sydney, Nova Scotia, Canada. Concentrations of PAHs were measured in surface soils, marine and estuary sediments prior to and during remediation of the Sydney Tar Ponds (STPs) site which was contaminated by nearly a century of coking and steel production. Previous studies identified PAHs in surficial marine sediments within Sydney Harbour, which were considered to be derived from STP discharges. Numerous PAH fingerprint techniques (diagnostic ratios, principal component analysis, quantitative and qualitative analysis) were applied to soil and sediment samples from the STPs and surrounding area to identify common source apportionment of PAHs. Results indicate coal combustion (from historical residential, commercial and industrial uses) and coal handling (from historic on-site stockpiling and current coal transfer and shipment facilities) are likely the principal source of PAHs found in urban soils and marine sediments, consistent with current and historical activities near these sites. However, PAH fingerprints associated with STP sediments correlated poorly with those of urban soils and marine sediments, but were similar to coal tar, historically consistent with by-products produced by the former coking operations. This study suggests PAH contamination of Sydney Harbour sediments and urban soils is largely unrelated to historic coking operations or recent remediation of the STPs site, but rather a legacy of extensive use of coal for a variety of activities.

Aquatic monitoring programs conducted during environmental impact assessments in Canada: preliminary assessment before and after weakened environmental regulation

Aquatic monitoring programs are imperative for the functioning of the environmental impact assessment (EIA) process and a cornerstone for industrial compliance in Canada. However, in 2012, several leading pieces of federal environmental legislation (e.g., Canadian Environmental Assessment Act c.19, s. 52, 2012) were drastically altered, effectively weakening levels of environmental protection for aquatic ecosystems during project developments. This paper assesses the impact of CEAA 2012 on aquatic monitoring programs (and subsequent monitoring data reporting) across Canada for ten projects (five completed pre-CEAA 2012 and five completed post-CEAA 2012). Projects included four energy and six mining projects and were selected based on the following criteria: (i) representative of Canada’s resource economy; (ii) project information was publicly available; and (iii) strong public interest. Projects pre- and post-CEAA 2012 exhibited few apparent differences before and after environmental regulatory changes. However, wide discrepancies exist in numbers and types of parameters reported, along with a lack of consistency in reporting. Projects pre-CEAA 2012 provided more follow-up monitoring commitments. Although qualitative differences remain inconclusive, this paper highlights requirements for further assessment of aquatic monitoring and follow-up programs in Canada. Recommendations for the government to consider during reviews of the federal environmental assessment processes include (i) improved transparency on the Canadian Environmental Assessment Agency website (https://www.ceaa-acee.gc.ca/); (ii) creation of a legally binding standardized aquatic monitoring program framework to ensure that all Canadian aquatic ecosystems are monitored with equal rigour; and (iii) commitments and justification related to frequency of aquatic monitoring of water quality.

Reducing marine pollution from single-use plastics (SUPs): A review

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 these have since been accompanied by recent increasing public awareness triggered by international agencies and organizations. The Sixth International Marine Debris Conference highlighted increasing intervention strategies to mitigate SUP pollution. This study presents new multi-jurisdictional legislative interventions to reduce SUPs since 2017 and incorporates emergence of new non-legislative interventions to mitigate other types of SUPs at individual and private-sector levels that complement or influence legislative interventions. Further, effectiveness of SUP bag interventions (e.g., bans vs. levies) to help reduce SUP marine pollution are presented and range between 33 and 96% reduction in bag use.

Characterization of polycyclic aromatic hydrocarbons (PAHs) in small craft harbour (SCH) sediments in Nova Scotia, Canada

Polycyclic aromatic hydrocarbons (PAHs) have been widely studied in sediments due to their ubiquity and persistence in aquatic environments and potential for impairment to biota. Small craft harbour (SCH) sediments in Nova Scotia (NS), Canada, have yet to be studied comprehensively. SCHs are essential to the fishing industry, which is important for the Canadian economy. This spatiotemporal characterization study evaluated thirty-one SCHs across NS between 2001 and 2017 by analyzing sediment reports (secondary data). Sediment PAH concentrations varied widely across all SCHs. Few SCHs exhibited sediment PAH concentrations likely to impair biota based on comparison to sediment quality guidelines. Sediments in the Gulf region of NS were least impacted by PAHs, while the Southwest region was most impacted. Distribution of individual PAHs in sediments follows global trends, with high molecular weight PAHs dominating samples.

North Atlantic right whales in danger

In 2017, an unprecedented mortality event occurred in the Gulf of St. Lawrence, Canada: Twelve endangered North Atlantic right whales were found dead ([ 1 ][1]–[ 3 ][2]). With fewer than 500 individuals remaining, North Atlantic right whales are federally protected in the United States and Canada