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Using citizen science to evaluate extended producer responsibility policy to reduce marine plastic debris shows no reduction in pollution levels


Abstract and Figures

As governments around the world grapple with the challenge of responding to increased plastic pollution, extended producer responsibility (EPR) policy, which shifts the responsibility for waste management of a product to producers, is quickly becoming a cornerstone of legislative approaches to this issue. However, the effectiveness of this policy has never been assessed in terms of reducing plastic marine debris. Understanding if a policy like EPR is having an effect requires collecting and analyzing information before and after a policy is introduced. Using British Columbia, Canada as a case study, we evaluate the influence of an EPR policy for packaging to reduce shoreline pollution. We use available citizen science data to demonstrate that there has been no reduction in pollution levels after the introduction of the policy. The findings also highlight some limitations when using citizen science data for a purpose it was not intended for. To effectively evaluate prevention of plastic pollution in the marine environment, plastic policy interventions require monitoring programs tailored to their specific requirements.
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Marine Policy 123 (2021) 104319
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Full length article
Using citizen science to evaluate extended producer responsibility policy to
reduce marine plastic debris shows no reduction in pollution levels
Lucas Harris
, Max Liboiron , Louis Charron , Charles Mather
Memorial University of Newfoundland, Department of Geography, 230 Elizabeth Ave, St. Johns, NL A1C 5S7, Canada
Extended producer responsibility
Citizen science
Plastic marine debris
Policy evaluation
As governments around the world grapple with the challenge of responding to increased plastic pollution,
extended producer responsibility (EPR) policy, which shifts the responsibility for waste management of a product
to producers, is quickly becoming a cornerstone of legislative approaches to this issue. However, the effectiveness
of this policy has never been assessed in terms of reducing plastic marine debris. Understanding if a policy like
EPR is having an effect requires collecting and analyzing information before and after a policy is introduced.
Using British Columbia, Canada as a case study, we evaluate the inuence of an EPR policy for packaging to
reduce shoreline pollution. We use available citizen science data to demonstrate that there has been no reduction
in pollution levels after the introduction of the policy. The ndings also highlight some limitations when using
citizen science data for a purpose it was not intended for. To effectively evaluate prevention of plastic pollution
in the marine environment, plastic policy interventions require monitoring programs tailored to their specic
1. Introduction
Plastic is a common and ubiquitous type of pollution in the marine
environment around the world. The San Francisco Bay area in California
alone is estimated to receive seven trillion plastic pieces annually [1].
Plastics are introduced into the marine environment from a variety of
land, air and sea-based sources [2]. As the global production of plastic
continues to increase every year [3], marine plastic pollution represents
a growing threat to socio-economic [4] and ecological [5] systems.
Packaging material in particular represents the single largest component
of plastics market demand around the world, accounting for 40% of total
plastic use in Europe [2] and 33% in Canada [6]. Packaging materials,
including food wrappers, plastic drink bottles, bottle caps, plastic gro-
cery bags and plastic lids, have also featured as the most frequently
found items during marine litter surveys [79].
Market-based strategies and policy interventions (e.g. bans, levies) to
minimize single-use plastics and packaging (e.g. plastic bags, microbe-
ads) have been rapidly increasing in the past 10 years [1012]. One
prominent policy approach that has been suggested to reduce marine
plastic pollution is Extended Producer Responsibility (EPR) [13]. As a
policy tool, EPR shifts the responsibility for waste management of a
product or its packaging from local governments to producers [14],
which provides incentives to producers to prevent waste from being
generated in the rst place (i.e. source reduction) [15], and reduces
material going to landll or leaking into the environment by funding,
creating or expanding infrastructure for post-consumer recycling [16].
Recently, several jurisdictions have adopted EPR as a pillar of their
legislative approach aimed at marine plastic pollution prevention, with
Canadian federal government [17], certain Canadian provinces [18] and
the European Union being recent examples [19].
However, EPR is difcult to assess in terms of its ability to reduce
plastic pollution in aquatic environments. The effectiveness of EPR
programs is typically measured using the volume of material recovered
from the conventional waste stream (i.e. curbside pickup, depot
collection) on an annual basis as a metric [20]. Monitoring the volume of
material that leaks from the waste stream into the marine environment
is not a reporting commitment for most programs. Furthermore, from a
methodological perspective, one core approach to understanding if an
intervention is having the desired outcomes uses quantication before
and after the intervention is introduced to evaluate impact [21]. Un-
fortunately, despite new [11] and existing strategies to address marine
plastic pollution, in many cases there is insufcient long-term moni-
toring data available that can be used to evaluate the effectiveness of
interventions [22]. To our knowledge and after sustained review of
* Correspondence to: Memorial University of Newfoundland, Department of Geography, 1440 Myrtle Ave, Victoria, BC V8R 2Z6, Canada.
E-mail address: (L. Harris).
Contents lists available at ScienceDirect
Marine Policy
journal homepage:
Received 28 March 2020; Received in revised form 14 October 2020; Accepted 9 November 2020
Marine Policy 123 (2021) 104319
English-language literature, there are no existing studies of the effec-
tiveness of EPR in reducing marine plastic pollution.
Citizen science has become integral in the development of data and
information on shoreline plastic marine pollution levels [23], lling a
gap in monitoring that often occurs due to constraints of time, resources
or geography [24]. Studies have found citizen science data were of
equivalent quality to those collected by accredited researchers [25] and
can be used to evaluate the effectiveness of a policy that has been
implemented [9,24]. In particular, the National Oceanic and Atmo-
spheric Administration (NOAA) states that standardized monitoring
frameworks used by citizen scientists can be used to evaluate the
effectiveness of policies to mitigate debris, such as recycling incentives
or EPR [26].
Here we provide an evaluation of the ability of EPR policy for
packaging material to reduce shoreline packaging pollution, using pre-
existing citizen science data generated during shoreline cleanup events
in British Columbia (BC), Canada as a case study. BC is the only juris-
diction in North America to have introduced 100% industry-funded EPR
legislation for packaging, beginning in 2014. Since the Recycle BC EPR
program launched, it has consistently recovered at least 75% of the
packaging and printed paper sold in the BC market on an annual basis
[2731], a major improvement from the estimated 52% recovery rate
pre-2014 [32] (see Table 1). BC also has eight organizations that
conduct citizen science shoreline monitoring work, three of which that
have used standardized frameworks to collect data on three packaging
pollution categories (plastic bags, food wrappers and six pack holders)
before and after the introduction of the EPR policy. However, recent
research of citizen science programs in BC demonstrates that most data
collection programs exist as a patchwork, with the majority of moni-
toring work focused at informing various policies, not evaluating them
[33]. This is the case in many jurisdictions around the world, in terms of
marine debris monitoring. As a result, this research provides a rare and
practical analysis of a policy that has been in place for several years,
using a data set similar to ones encountered in other jurisdictions. By
doing so, we outline the challenges and considerations of using this
citizen science data to evaluate policy interventions.
2. Materials and methods
EPR policy for packaging material in BC was regulated in 2011 [34]
and introduced on May 19, 2014 in a majority of municipalities across
the province [35]. Our analyses use pre-existing shoreline pollution
datasets that have been generated by, and obtained from, eight citizen
science shoreline cleanup organizations operating in BC. None of these
datasets were created to evaluate EPR. After reviewing the data sets,
only three of the organizations had data that recorded
packaging-specic categories before and after the introduction of EPR in
2014. The Great Canadian Shoreline Cleanup (GCSC) use a tally sheet
modeled from the International Coastal Cleanup, and two chapters of the
Surfrider Foundation use the eld guide developed by NOAA [36].
These data sets were then included in three different statistical analysis
routine: GCSC, Surfrider Vancouver and Vancouver Island Chapters
(combined) and urban versus remote sites. The number of material
categories (e.g. buoys, oats, cigarette butts, etc.) in these data sets used
to track pollution levels range from 26 to 56. For analytical purposes,
categories were removed from each dataset that were not aligned with
the denition of packagingin the BC Environmental Management Act,
narrowing the categories to three that have been consistently recorded
throughout each data set: plastic bags, six-pack holders and food
2.1. Great Canadian Shoreline Cleanup (GCSC)
The GCSC, which uses a tally method (count) similar to the Inter-
national Coastal Cleanup, frequently hosts cleanup events. The GCSC
data set includes 5752 records for shoreline cleanup events in BC, from
2008 to 2017. For analytical purposes, a subset of data was generated
that eliminated records that lacked material-specic results and
included sites with consistent records for three years before and after the
introduction of EPR in 2014, for a total of seven years of data
(20112017). The remaining data set includes 147 records, across 21
different shoreline cleanup sites.
The GCSC data collection method does not control for length of the
beach cleaned (kilometers) or the amount of people (people) partici-
pating in a cleanup event. However, these factors can each be expected
to have an inuence on the collection results. To address this, the
number of collected packaging items (combined total of plastic bags,
food wrappers and six-pack holders) was divided by the length of beach
surveyed and linear mixed-effect models were constructed with the
random effects: site and number of people. Models were constructed
using the function lmer of the lme4′′ package [37]. To meet the as-
sumptions of residuals homogeneity, normality and independence, the
response variable was ln-transformed +0.0001. To evaluate the inu-
ence of the EPR policy on packaging shoreline debris levels after it was
introduced, we performed model selection based on Akaikes informa-
tion criterion (AICc; to control for small sample size). Model selection
was performed on a set of candidate models (Table 2). Two models were
used: (1) a null model, including the random effects of site and number
of people and (2) a complete model, including the xed effect of year
and the random effects. Marginal and conditional goodness-of-t (R
were computed following the procedure of Nakagawa et al. [38]. Sum-
mary of the models allowed us to determine the importance of year
(proxy for EPR policy) on packaging debris levels.
We also performed a t-test on pre- and post-2014 packaging debris
levels, and an ANOVA. These analyses were limited and not adequate
when compared to the mixed-model approach, as they do not control for
beach size, site or the number of people, but showed that there was no
signicant difference in packaging debris levels from year to year.
2.2. Surfrider Foundation: Vancouver and Vancouver Island Chapters
Data from the Vancouver and Vancouver Island Chapters of the
Surfrider Foundation were used to analyze packaging material shoreline
deposition trends in the Vancouver and Victoria areas. The Surfrider
datasets are created in accordance with the NOAA Shoreline Survey
Field Guide (2012). The NOAA Field Guide uses a tally method (count)
and controls for length of shoreline by utilizing a 100 m transect. It also
controls for effort by typically having a limited number of people
perform the monitoring work and recording the number of people.
There is a combined total of 81 records from both Surfrider datasets
for shoreline cleanup events at locations in both Vancouver and Victoria
from 2011 to 2017. For analytical purposes, a subset of data was
generated that eliminated records that lacked data before and after the
introduction of EPR in 2014. The data set was also limited to sample sites
in municipalities that are participating in the EPR program. The
remaining dataset includes 37 records, across eight different shoreline
cleanup sites (seven in Victoria and one in Vancouver).
To test the effect of the introduction of EPR policy for packaging
(combined total of plastic bags, food wrappers and six-pack holders) on
Table 1
Annual recovery rates for all packaging and printed paper managed in the
Recycle BC EPR Program.
Recycle BC packaging and paper products annual recovery rates
Year 2014
2015 2016 2017 2018
Product sold (tonnes) 145,351 243,191 238,062 234,847 235,655
Product collected
116,457 186,509 185,477 174,942 183,983
Recovery rate 80% 77% 78% 75% 78%
As per the regulation, the program launched on May 19, 2014, therefore it
did not operate for the entire year. As a result, this data reects 7.5 months of
L. Harris et al.
Marine Policy 123 (2021) 104319
shoreline packaging debris levels, we performed an analysis of variance
(ANOVA) on a generalized linear model with Poisson distribution, to
account for count data. We used site, yearand their interaction as
covariates. Models were constructed using the function glm. All
models met the assumptions of residuals homogeneity, normality and
independence. We also performed a paired t-test to determine packaging
pollution trends over time, by pairing site before and after the intro-
duction of EPR in 2014. For sites that had more than one cleanup event
before or after 2014, the average value of packaging debris over these
groups of years was used.
2.3. Urban versus remote sites
The Vancouver Island Chapter of the Surfrider Foundation is the only
organization that has collected data from sample sites in both urban and
remote locations consistently over time. Their data was used to analyze
packaging material shoreline deposition trends between urban and
remote sample sites. There is a total of 56 records between 2011 and
2017 across 13 different sample sites on the south west coast of Van-
couver Island. 29 records are from sample sites in remote locations and
27 records are from sample sites in urban areas.
To test the difference in packaging pollution levels (combined total
of plastic bags, food wrappers and six-pack holders) between shoreline
“type (urban or remote), we performed an analysis of variance
(ANOVA) on a generalized linear model with Poisson distribution, to
account for count data. We used year, typeand their interaction as
covariates. Models were constructed using the function glmin R. All
models met the assumptions of residuals homogeneity, normality and
All analyses were done using R version 3.6.2 [39]. The data from this
study is subject to third party restrictions. The data that support the
ndings from this study are available from the various citizen science
organizations that participated but restrictions apply to the availability
of these data, which were used under license for the current study, and
so are not publicly available. Data are however available from the au-
thors upon reasonable request and with permission of the particular
citizen science organization.
3. Results
3.1. Great Canadian Shoreline Cleanup
Mixed-effect modeling demonstrated that the introduction of EPR in
2014 did not signicantly inuence packaging pollution levels on
shorelines. The AICc selection procedure (Table 2) determined that the
null model (only including the random effects) was the most parsimo-
nious. Year did not improve the model, meaning that year does not have
a signicant inuence on packaging debris levels (marginal R
(Fig. 1). It can be noted, however, that a higher proportion of the vari-
ance in shoreline packaging debris levels was explained by the random
effects of site and people (conditional R
3.2. Surfrider Foundation - Vancouver and Vancouver Island Chapters
Data from the Vancouver and Vancouver Island Chapters of the
Surfrider Foundation was also used to analyze packaging material
shoreline deposition trends in the Vancouver and Victoria areas, in
relation to the introduction of EPR policy. The results of the ANOVA
demonstrate that there is a strong effect of the interaction of site and
year (p-value <0.00001), with different trends occurring over time at
every site. Some sites show an upward trend in pollution levels, while
others show a constant or downward trend (see Fig. 3). Nevertheless,
there is also a year effect, showing an overall trend in which packaging
pollution is increasing over time (p-value 0.001486) (see Figs. 2 and 3).
Since site has a strong effect, we also performed a paired t-test (by
site) on packaging pollution levels before (pre) and after (post) the
introduction of EPR in 2014. Sites before 2014 had a mean value of 11.1
pieces of packaging, while sites after had a mean value of 19.9 pieces.
Each site has its own trend (increase, decrease or constant in packaging
pollution) and the difference pre- post- EPR is not statistically signicant
(p-value 0.2; see Fig. 3).
This data set has a strong site-specic trend. In particular, the results
of the ANOVA demonstrate that packaging pollution levels at each site
are very different from the next (p-value 0.00001). The t-test, which
accounts for site, does not show any signicant difference in pollution
levels before or after the introduction of EPR in 2014 (p-value 0.2). This
result is driven by a few sites that have seen their pollution level increase
drastically (e.g. Willows Beach in Victoria). Using the NOAA method
allowed the two Surfrider chapters to develop a good quality records
within their data sets. However, the sample size is somewhat limited.
Having more records over time would allow for the ability to better
Table 2
AIC model selection results for GCSC data. Results demonstrate how year accounts for less than 1% of the variance in the data, while site and people account for 19%.
Model K AICc Delta AICc LL Marginal R
Conditional R
Null Packaging/km ~ (1|Site) +(1|People) 4 623.768 0.000 307.743 0.000 0.193
Year Packaging/km ~ Year +(1|Site) +(1|People) 5 624.212 0.444 306.893 0.009 0.206
Fig. 1. GCSC Mean Packaging Pollution Levels. Plot of GCSC mean packaging
pollution levels for three years before and after the introduction of packaging
EPR in BC in 2014.
Fig. 2. Surfrider Vancouver and Vancouver Island Mean Packaging Pollution
Levels. Plot of mean packaging levels for each year in the data set, demon-
strating the increase in packaging pollution after 2014.
L. Harris et al.
Marine Policy 123 (2021) 104319
dene the trend.
3.3. Urban versus remote sites
Analysis of the Surfrider Vancouver Island data set by itself is aimed
at determining the difference on packaging pollution levels between
urban and remote locations. The results of the ANOVA demonstrate that
there is a strong effect of the interaction of year and type, with shoreline
types not reacting the same way over year (see Table 3 and Fig. 4). But
even across year, the mean packaging number has been consistently
lower in remote sites, when compared to urban.
Overall, the packaging pollution deposition pattern over time be-
tween remote and urban shoreline sites has varied. Deposition patterns
appear similar in earlier years. But it is evident that remote areas have a
constant rate of pollution, while urban sites have seen levels increase
over time. This increase in urban areas in driven by some extreme values
in 2015 and 2016.
4. Discussion
EPR is a relatively new policy approach for marine plastic pollution
prevention. While many have suggested that EPR policies can prevent or
reduce plastic pollution in the marine environment [13,15,16], there is
no pre-existing research available to test this assumption. Here we show
that there is no signicant reduction in packaging debris levels after the
introduction of EPR in 2014 British Columbia, Canada based on existing
citizen science data, even though the EPR program has been able to
demonstrate an increase in material recovery. This data is unable to
evaluate whether this is due to an overall increase in plastic waste
despite some signicant amount being diverted to material recovery,
whether there is an increase in plastic waste from areas outside of BC
coming onto BC shorelines, or whether there are different trends in
plastics outside of the three packaging types investigated. Other trends
detected include that the mean packaging number has been consistently
lower in remote sites, when compared to urban areas and that there is
high variability within collection sites.
While we believe these results are valid, they are also based on
acutely limited data. Citizen science has been identied as a legitimate
source of information that can support research [23], education [40]
and the introduction [41] and evaluation [24] of a particular pollution
prevention policy or legislation. However it should be clear that we used
pre-existing citizen science datasets generated by organizations that
collected the data for other reasons, such as supporting policy devel-
opment and informing education and awareness programs. As detailed
in the methods, to make the data correspond with the denition of
“packagingin the BC Environmental Management Act so it could be used
to evaluate EPR, there was an acute reduction of the amount of data that
could be used. Thus, this study is using limited data that mainly de-
scribes only three types of packaging rather than the breadth of mate-
rials covered under the packaging EPR program and the BC
Environmental Management Act. This is not a limitation of citizen science
data per se but rather the limitation of using citizen science data for
purposes other than those for which it was collected.
As policy interventions are introduced, there is a temptation to use
citizen science data to evaluate them. But there are acute limitations to
using data this way. Instead, we recommend that policy interventions
create data frameworks for monitoring and evaluation that directly
measure their full range of targets and anticipated outcomes, including
plastic marine debris reduction. In particular, a successful data collec-
tion approach for evaluating the ability of EPR for packaging material to
reduce shoreline plastic pollution levels should address several key
factors, which include identifying the source of debris, performing
frequent monitoring, establishing material categories consistent with
the policy and using count as the primary metric for tracking, due to the
fact that recent light-weighting of packaging items has the potential to
skew collection results based on weight.
The data in this study was obtained under the Interdisciplinary
Committee on Ethics in Human Research (ICEHR) at Memorial Univer-
sity of Newfoundland approval Aligning Citizen Science and Extended
Producer Responsibility Policy for Marine Plastic Reduction
(20190638-AR) for the period 08/24/18 08/31/19.
This work was supported by the Canadian Social Science and Hu-
manities Research Council [grant number 430-2015-00413].
Fig. 3. Surfrider Vancouver and Vancouver Island Paired Data. Plot of paired
data for mean values of packaging for sites before (pre) and after (post) the
introduction of EPR in 2014. Each line represents a specic site.
Table 3
ANOVA for Surfrider Vancouver Island data. Results of the ANOVA for Surfrider
Vancouver Island data demonstrate that there is a strong interaction of year*-
type effect, with shoreline types not reacting the same way over year.
Df Deviance Resid. Df Resid. Dev Pr (>Chi)
Null 55 935.08
Year 1 62.9 54 872.21 2.212 ×10
Type 1 186.7 53 685.51 <2.2 ×10
Year:Type 1 52.1 52 633.41 5.292 ×10
Fig. 4. Surfrider Vancouver Island Urban and Remote Mean Pollution Levels.
Plot of mean packaging levels (combined total of food wrappers, plastic bags
and six-pack holders) in the Surfrider Vancouver Island data set each year,
showing results for both urban and remote shoreline site types. Error bars
represent the standard error of the mean.
L. Harris et al.
Marine Policy 123 (2021) 104319
CRediT authorship contribution statement
Lucas Harris: Conceptualization, Methodology, Software, Valida-
tion, Formal analysis, Investigation, Data curation, Writing original
draft, Writing review & editing, Visualization, Project administration.
Max Liboiron: Conceptualization, Methodology, Formal analysis, Re-
sources, Writing review & editing, Supervision, Funding acquisition.
Louis Charron: Methodology, Software, Validation, Formal analysis,
Writing review & editing, Visualization. Charles Mather: Conceptu-
alization, Writing review & editing, Supervision.
Declaration of interest
Lucas Harris is a previous executive committee member of the
Vancouver Island Chapter of the Surfrider Foundation, one of the or-
ganizations that provided shoreline pollution data for this research.
Lucas is also currently a Senior Policy Analyst with the extended pro-
ducer responsibility section of the BC Ministry of Environment and
Climate Change Strategy. He was previously the le lead for the pack-
aging EPR program but is currently assigned to a different le.
We thank the volunteers and staff from the citizen science organi-
zations, EPR program and government agency who contributed infor-
mation used in the analysis herein. We gratefully acknowledge shoreline
litter data supplied by the Great Canadian Shoreline Cleanup, a con-
servation partnership by Ocean Wise and WWF-Canada. We also thank
Dr. Brett Favaro at the Fisheries and Marine Institute of Memorial Uni-
versity of Newfoundland for guidance on statistical analysis related to
this project. This research was conducted in the Civic Laboratory of
Environmental Action Research (CLEAR) at Memorial University of
Newfoundland and we acknowledge the generous feedback and support
from lab members during the span of this project. In particular, we thank
Kaitlyn Hawkins and Pamela Murphy for providing administrative
support, with regard to funding for this project. We would also like to
thank Dr. Kate Parizeau and Dr. Josh Lepawsky for reviewing Lucas
Harriss MSc thesis, which this article is based on. We also thank Neil
Nunn, Kelsey Singbeil, Owen Harris for providing care and support
throughout the research process.
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... However, two primary challenges arise with citizen science. First, comparing citizen science studies with those following the scientific method can be a challenge because there is often a difference in methodologies to meet their respective goals (Harris, 2019). Second, there are some types of plastic work (e.g., micro-and nanoplastics) that require great care and protocols in collection due to contamination issues, and they may not be appropriate for citizen science work. ...
Lack of knowledge on levels and trends of litter and microplastic in the Arctic, is limiting our understanding of the sources, transport, fate and effects is hampering global activities aimed at reducing litter and microplastic in the environment. To obtain a holistic view to managing litter and microplastics in the Arctic, we considered the current state of knowledge and methods for litter and microplastics monitoring in eleven environmental compartments representing the marine, freshwater, terrestrial and atmospheric environments. Based on available harmonized methods, and existing data in the Arctic, we recommend prioritization of implementing litter and microplastics monitoring in the Arctic in four Priority 1 compartments - water, aquatic sediments, shorelines and seabirds. One or several of these compartments should be monitored to provide benchmark data for litter and microplastics in the Arctic and, in the future, data on spatial and temporal trends. For the other environmental compartments, methods should be refined for future sources and surveillance monitoring, as well as monitoring of effects. Implementation of the monitoring activities should include community-based local components where possible. While organized as national and regional programs, monitoring of litter and microplastics in the Arctic should be coordinated, with a view to future pan-Arctic assessments.
... Articles that deal with policies clustered in this category 3 mostly focus on the EU but also analyze policies in Germany [31], the UK [26,32] as well as British Columbia and Nova Scotia in Canada [33,34]. ...
This review analyses the subject focus of 45 articles (published 2019–2021), dealing with government action to regulate plastic pollution. Policies described in the articles and introduced between 2016 and 2021 are clustered in four categories: production – consumption – disposal – circular approaches. Our results show that most articles are dealing with bans on single-use plastic (SUP) items in one or more countries. While SUP bags are still the most regulated items, there is a growing number of regulations on other SUP items, such as Styrofoam products or microbeads. While policies and research focus heavily on the consumption phase, the production phase is not only under-regulated, but also under-researched.
... However, two primary challenges arise with citizen science. First, comparing citizen science studies with those following the scientific method can be a challenge because there is often a difference in methodologies to meet their respective goals (Harris, 2019). Second, there are some types of plastic work (e.g., micro-and nanoplastics) that require great care and protocols in collection due to contamination issues, and they may not be appropriate for citizen science work. ...
Technical Report
Full-text available
The purpose of the guidelines is to review existing knowledge and provide guidance for designing an Arctic monitoring program that will track litter and MP. The topics of litter, plastic pollution, and MP are addressed in many fora, including several of the Arctic Council working groups: Arctic Monitoring and Assessment Programme (AMAP;, Protection of the Marine Environment (PAME, 2019), and Conservation of the Arctic Flora and Fauna (CAFF). The development of an Arctic monitoring program and its technical approaches will be based on the work that already exists in other programs such as those of OSPAR, the Helsinki Commission (HELCOM), the International Council for the Exploration of the Sea (ICES), the Organisation for Economic Co-operation and Development (OECD), and the United Nations Environment Programme (UNEP). Plastic pollution is typically categorized into items and particles of macro-, micro-, and nano-sizes. These guidelines address macrosized litter as well as MP (< 5 mm), essentially including smaller size ranges (>1 µm). However, determination of nanoplastic (< 1 µm) particles is still hampered by technical challenges, as addressed in Section 4.3 Analytical methods, and thus not currently considered in the current recommendations. Although most studies have addressed marine litter and MP, these guidelines also comprise the Arctic’s terrestrial and freshwater environments. Thus, the objectives of the guidelines are to: 1) support litter and MP baseline mapping in the Arctic across a wide range of environmental compartments to allow spatial and temporal comparisons in the coming years; 2) initiate monitoring to generate data to assess temporal and spatial trends; 3) recommend that Arctic countries develop and implement monitoring nationally via community-based programs and other mechanisms, in the context of a pan-Arctic program; 4) provide data that can be used with the Marine Litter Regional Action Plan (ML-RAP) to assess the effectiveness of mitigation strategies; 5) act as a catalyst for future work in the Arctic related to biological effects of plastics, including determining environmentally relevant concentrations and informing cumulative effects assessments; 6) identify areas in which research and development are needed from an Arctic perspective; and 7) provide recommendations for monitoring programs whose data will feed into future global assessments to track litter and MP in the environment. To achieve these objectives, the guidelines present indicators (with limitations) of litter and MP pollution to be applied throughout the Arctic, and thus, form the basis for circumpolar comparability of approaches and data. In addition, the guidelines present technical details for sampling, sample treatment, and plastic determination, with harmonized and potentially standardized approaches. Furthermore, recommendations are given on sampling locations and sampling frequency based on best available science to provide a sound basis for spatial and temporal trend monitoring. As new data are gathered, and appropriate power analyses can be undertaken, a review of the sampling sizes, locations, and frequencies should be initiated. Plastic pollution is a local problem in Arctic communities, and thus, guidelines and references need to include community-based monitoring projects to empower communities to establish plastics monitoring with comparable results across the Arctic. Community-based monitoring is an integrated part of the objectives of this report. The monitoring program design and guidelines for its implementation are the necessary first steps for monitoring and assessment of litter and MP in the Arctic. The work under the AMAP LMEG is taking a phased approach under this new expert group. The first phase (which included the development of these Monitoring Guidelines) focuses on a monitoring framework and set of techniques for physical plastics. Later phases of the work will extend to assessments of levels, trends, and effects of litter and MP in the Arctic environment. The guidelines strictly cover environmental monitoring of litter and MP. This does not include drinking water or indoor air quality tests. Additionally, although there is an emphasis on examining litter and MP in biota that are consumed by humans, and thus of interest to human-health questions, the guidelines do not consider MP ingestion by humans.
... Given the ubiquity of plastic packaging in the supply chain, there is no question that effective efforts must be coordinated at scale (Vince and Hardesty, 2016). At the same time, such coordination necessarily comes at the expense of local and regional autonomy -and in spite of the fact that there exists significant regional variation in Canadians' attitude towards plastics regulation (Walker et al., 2021 Even as support grows for extended producer responsibility and the circular economy, the evidence is ambiguous as to these policies' feasibility and effectiveness (Brouwer et al., 2020;Harris et al., 2021;Bala et al., 2020). ...
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Plastic waste is a global environmental problem. However, management solutions must be developed within local, institutional contexts. This paper considers the Government of Canada’s ‘proposed integrated management approach to plastic products’ both as a strategy for management and as an expression of federal jurisdiction. What is the policy problem to which they are responding, and how are they characterizing that problem in order to claim jurisdiction? Most importantly, what are the policy implications of this jurisdictional question?
The production of plastics has rapidly overwhelmed the world's ability to manage it, hence the demanding environmental issues on plastics pollution. The negative effects of plastics have become omnipresent and prompted many studies to be conducted leading to a global treaty. This study focused on reviewing measures for preventing plastic pollution in the environment. Based on the literature review approach, seven key measures are identified: recycling prioritization, utilization of bio-based and biodegradable plastics, improvement of waste collection systems, awareness and education in communities, extended producer responsibility (EPR) enforcement, strengthen stakeholder engagement, and technology and innovations. The study concludes by providing practical recommendations that should be implemented contextually.
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Marine litter is a significant threat to the marine environment, human health, and the economy. In this study, beach litter surveys along Vietnamese coasts were conducted in a local context to quantify and characterize marine litter using the modified GESAMP marine litter monitoring guideline. A total of 21,754 items weighing 136,820.2 g was recorded across 14 surveys from September 2020 to January 2021. Plastic was the most abundant type of litter by both quantity (20,744 items) and weight (100,371.2 g). Fishing gear 1 (fishing plastic rope, net pieces, fishing lures and lines, hard plastic floats) and soft plastic fragments were the most frequently observed items (17.65% and 17.24%, respectively). This study not only demonstrates the abundance and composition of marine litter in Vietnam, it also provides valuable information for the implementation of appropriate preventive measures, such as the redesign of collection, reuse, and recycling programs, and informs policy and priorities, with a focus on action and investment in Vietnam. Moreover, insights from this study indicate that citizen science is a useful approach for collecting data on marine litter in Vietnam.
In April 2021, Japan's decision to dump nuclear wastewater into the ocean has raised worldwide attention. Therefore, to focus on seafood safety from firm and government in this event, we construct a game model to explore the technology-enabled ways to resolve conflict from domestic product and polluted product. Our analysis reveals the potential equilibrium strategy for the domestic product only and two types of products, respectively. Moreover, from the perspective of government punishment, the result shows the existing motivation of polluted product in the market. Finally, we also investigate the five aspects to find the changes of market share for domestic product, including customer choice, product freshness, market uncertainty, geographical distance, and shoddy product, respectively. In summary, this research provides management implications to resolve conflict between two types of products and to realize the multi-party balance of interests and technology-enabled value.
Despite the global implementation of plastic waste reduction policies and bans on single use plastics (SuPs), their effectiveness for protecting marine ecosystems remains unclear. Frequent monitoring could confirm policy effectiveness, but this is difficult due to resourcing and logistic constraints. This study tested a ‘beach litter’ beachcombing citizen science approach that could overcome some constraints. Between November 2018 and January 2021, 168 beach visits led to the collection of 12,659 pieces of litter from a beach in Western Australia. Litter was predominantly plastic (87%) and mostly associated with fishing/boating (34%). Significant reductions in six types of litter, including fishing/boating items, balloons, and straws were detected and four coincided with local government waste mitigation measures. We show potential to harness conscientious beachcombers as citizen scientists to help evaluate plastic policy impact. Furthermore, we propose how to harness this effort and increase spatial and temporal coverage of marine plastic pollution monitoring.
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Single-use plastics (SUPs) represent a major threat to marine environments and require proactive policies to reduce consumption and mismanagement. Many SUP management strategies exist to reduce SUP use and mitigate environmental impacts, including extended producer responsibility (EPR), deposit-return schemes, SUP bans or taxes, and public outreach and education. This study analyzed brand audit and beach cleanup data in four densely populated Canadian cities (Vancouver, Toronto, Montréal, Halifax) and a remote island (Sable Island) to determine efficacy of ongoing SUP mitigation measures. Cites were found to have similar litter type proportions, and six brands were found to disproportionally contribute to Canadian SUP litter, comprising 39% of branded litter collected). Results confirm current Canadian SUP measures appear to be insufficient to address leakage of SUPs into the environment. Recommendations to strengthen SUP management strategies and mitigate plastic pollution are recommended to improve future Canadian SUP reduction policies.
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Macro-marine debris becomes a global thorny issue to human beings and people are keeping trying every means to mitigate the risk of it. In this paper, we propose to use vessel and develop optimal vessel routing network to collect macro-marine debris on the nearshore surface. Due to the integrated force of winds and ocean currents, debris constantly changes floating location in the ocean. Advanced remote sensing technology and General National Oceanic and Atmospheric Administration (NOAA) Operational Modeling Environment (GNOME) software are employed to identify debris locations and track the drifting trajectory, respectively. In order to balance collecting efficiency and vessel emission reduction, we propose a bi-objective mixed integer nonlinear programming model for vessel routing to minimize travel time and carbon emission, considering time window at debris location, vessel capacity, low/medium/high vessel speed, and cost including carbon tax. A novel pheromone heuristic adaptive large neighborhood search (PHALNS ) algorithm combined with archived multi-objective simulated annealing (AMOSA) mechanism is developed to solve the proposed model. The Yangtze River Estuary region is taken as a numerical example to verify the proposed model and algorithm. Six criterions are introduced to evaluate the best collection time, and the proposed algorithm is also compared with NSGA II algorithm. The results show that low carbon emission and cost effective could be achieved simultaneously, and vessel speed has larger impact than the route scheme.
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The coefficient of determination R ² quantifies the proportion of variance explained by a statistical model and is an important summary statistic of biological interest. However, estimating R ² for generalized linear mixed models (GLMMs) remains challenging. We have previously introduced a version of R ² that we called R ² GLMM for Poisson and binomial GLMMs, but not for other distributional families. Similarly, we earlier discussed how to estimate intra-class correlation coefficients ICC using Poisson and binomial GLMMs. In this article, we expand our methods to all other non-Gaussian distributions, in particular to negative binomial and gamma distributions that are commonly used for modelling biological data. While expanding our approach, we highlight two useful concepts for biologists, Jensen’s inequality and the delta method, both of which help us in understanding the properties of GLMMs. Jensen’s inequality has important implications for biologically meaningful interpretation of GLMMs, while the delta method allows a general derivation of variance associated with non-Gaussian distributions. We also discuss some special considerations for binomial GLMMs with binary or proportion data. We illustrate the implementation of our extension by worked examples from the field of ecology and evolution in the R environment. However, our method can be used across disciplines and regardless of statistical environments.
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Mil­lions of tonnes of vir­gin (pri­mary) plas­tic are pro­duced an­nu­ally, while re­cov­er­able (sec­ondary) plas­tic rapidly ac­cu­mu­lates as waste in land­fills and the en­vi­ron­ment. Sin­gle-use plas­tics (SUPs) have short lifes­pans, and most of this waste is gen­er­ated by pack­ag­ing from global food in­dus­tries. Food pack­ag­ing waste com­prises ap­prox­i­mately one-third (8 mil­lion tonnes) of all Cana­dian mu­nic­i­pal solid waste, and only 20% is re­cov­ered for reuse or re­cy­cling. Ex­tended pro­ducer re­spon­si­bil­ity (EPR) strate­gies lever­age cor­po­rate re­sources to re­duce SUP waste gen­er­ated by con­sumers. Im­ple­men­ta­tion of EPR strate­gies al­lows lo­cal ju­ris­dic­tions to gain greater con­trol over their waste streams. Al­though Canada has had a na­tional EPR strat­egy since 2009, it is cur­rently only im­ple­mented for pack­ag­ing in five provinces (e.g., British Co­lum­bia, Saskatchewan, Man­i­toba, On­tario and Québec), and is cur­rently un­der de­vel­op­ment in New Brunswick. In this short com­mu­ni­ca­tion, a case ex­am­ple of EPR im­ple­men­ta­tion in Nova Sco­tia is pro­vided which high­lights the po­ten­tial eco­nomic ben­e­fits for mu­nic­i­pal­i­ties ($14–17 M CAD in es­ti­mated sav­ings), for im­proved solid waste man­age­ment and for in­creas­ing re­cy­cling rates. Fur­ther, a re­gional EPR strat­egy is rec­om­mended for all At­lantic Cana­dian provinces (e.g., New­found­land and Labrador, New Brunswick, Prince Ed­ward Is­land and Nova Sco­tia) now that the Cana­dian fed­eral gov­ern­ment has an­nounced a move to­wards zero plas­tic waste un­der the Ocean Plas­tics Char­ter.
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Countries in Africa are increasingly adopting policies to reduce single-use plastic (SUP) pollution, yet there has been limited analysis of policies adopted by African countries. This paper reviews SUP reduction policies, specifically in West Africa. The main policy instruments used by countries in West Africa is legislative SUP bans mostly on plastic grocery bags. Of the 16 countries, 11 have instituted bans, one has a market-based instrument and rest (4) with no strategy. Bans carry hefty punishments (i.e., fines and prison sentences). However, there is limited consultation when drafting bans, no national campaigns, and limited notification (less than one year) between ban announcement and subsequent implementation. There are no provisions for re-useable alternatives. We recommend current and future policies to reduce SUPs should engage stakeholders, allow sufficient time between announcement and implementation where the policy should be widely publicised. Governments are encouraged to offer inexpensive re-useable alternatives.
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This study measured spatial distribution of marine debris stranded on beaches in South Eleuthera, The Bahamas. Citizen science, fetch modeling, relative exposure index and predictive mapping were used to determine marine debris source and abundance. Citizen scientists quantified debris type and abundance on 16 beaches within three coastal exposures (The Atlantic Ocean, Great Bahama Bank and The Exuma Sound) in South Eleuthera. Marine debris, (~2.5 cm or larger) on each beach was monitored twice between March-May and September-November 2013 at the same locations using GPS. Approximately, 93% of all debris items were plastic with plastic fragments (≤2.5 cm) being the most common. There were spatial differences (p ≤ 0.0001) in plastic debris abundance between coastal exposures. Atlantic Ocean beaches had larger quantities of plastic debris by weight and by meter (m) of shoreline. Stranded plastic may be associated with Atlantic Ocean currents associated with leakage from the North Atlantic subtropical gyre.
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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 33-96% reduction in bag use.
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A common situation in the evaluation of intervention programs is the researcher's possibility to rely on two waves of data only (i.e., pretest and posttest), which profoundly impacts on his/her choice about the possible statistical analyses to be conducted. Indeed, the evaluation of intervention programs based on a pretest-posttest design has been usually carried out by using classic statistical tests, such as family-wise ANOVA analyses, which are strongly limited by exclusively analyzing the intervention effects at the group level. In this article, we showed how second order multiple group latent curve modeling (SO-MG-LCM) could represent a useful methodological tool to have a more realistic and informative assessment of intervention programs with two waves of data. We offered a practical step-by-step guide to properly implement this methodology, and we outlined the advantages of the LCM approach over classic ANOVA analyses. Furthermore, we also provided a real-data example by re-analyzing the implementation of the Young Prosocial Animation, a universal intervention program aimed at promoting prosociality among youth. In conclusion, albeit there are previous studies that pointed to the usefulness of MG-LCM to evaluate intervention programs (Muthén and Curran, 1997; Curran and Muthén, 1999), no previous study showed that it is possible to use this approach even in pretest-posttest (i.e., with only two time points) designs. Given the advantages of latent variable analyses in examining differences in interindividual and intraindividual changes (McArdle, 2009), the methodological and substantive implications of our proposed approach are discussed.
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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.
Beach accumulation surveys can be used as a proxy to estimate litter flows into the marine environment. However, litter loads can be influenced by various factors including catchment area characteristics, weather conditions and ocean water movements. This complexity is evidenced by the results of five beach surveys conducted in Cape Town in 2017. Observed average litter accumulation rates across the beaches ranged from 36 to 2961 items·day −1 ·100 m −1. Item mass ranged from 0.01-367 g, with items weighing < 1 g contributing 61-85% of count. Plastic items accounted for 94.5-98.9% of total count and this prevalence appears to have increased relative to older data (1989-1994). The top ten identifiable items accounted for 40-57% of plastic debris. Nine of these were associated with foods commonly consumed on-the-go, including polystyrene packaging , snack packets and straws. A mitigation approach focused on these items may address one third to one half of marine litter sources in Cape Town.
This paper analyzes voluntary cleanups organized by the Great Canadian Shoreline Cleanup (GCSC) along the coast of British Columbia (2013–2016). Cleanup performance indicators, litter composition and diversity were compared between years and across areas (i.e., North Coast of British Columbia, Inner Coast of Vancouver Island, West Coast of Vancouver Island, and Southern Strait of Georgia). Significant differences in parameters were found between areas but not across time. Spatial variation in trash composition and diversity was mostly related to source of litter. Trash yield per kilometre of shoreline was higher in isolated areas and in areas with exposed shorelines. The majority of recovered litter items were composed of plastic. Local actions, complementary to the GCSC, such as banning single-use, non-biodegradable takeout containers on beaches, implementing trash buyback programs, and modifying waste management and recycling regulations, are proposed as mechanisms for strengthening the prevention and mitigation of coastal pollution in British Columbia.
Plastic marine debris is a global problem, but due to its widespread and patchy distribution, gathering sufficient samples for scientific research is challenging with limited ship time and human resources. Taking advantage of public interest in the impact of plastic on the marine environment, successful Citizen Science (CS) programs incorporate members of the public to provide repeated sampling for time series as well as synoptic collections over wide geographic regions. A key challenge with any CS program is to ensure standardized methods and quality control so that the samples and data can legitimately be compared and used in peer-reviewed research. This article describes several successful examples and outlines suggestions for projects cooperating with citizen scientists to provide reliable samples and accurate data, with benefits to science, citizen scientists, and society in general.