This chapter quantifies the projected environmental consequences of the plastic lifecycle in the ASEAN Plus Three (APT) region through 2050, under current policies. It focuses on two main impact areas: leakage of plastics to the environment (including leakage to freshwater and oceans, accumulated aquatic pollution, and transboundary flows) and plastics-related greenhouse gas (GHG) emissions. The analysis shows that, despite the projected APT’s declining share of global leakage, plastic pollution in the APT is projected to continue to increase. The chapter provides a breakdown of leakage pathways, identifying hotspots and flows across the APT.
Regional Plastics Outlook for Southeast and East Asia
Abstract
Without additional policies, leakage of plastics in APT countries is projected to increase by 68%, from 8.4 Mt in 2022 to 14.1 Mt in 2050. Expected improvements in waste management systems are projected to help temper growth in leakage, but not enough to reverse current trends.
As leakage is projected to grow even more rapidly in some other parts of the world (e.g. Sub-Saharan Africa), the contribution of the APT to global leakage is projected to slightly decline over time, from 38% in 2022 to 35% in 2050.
Regional disparities within the APT drive diverging leakage trajectories. The ASEAN group of countries is projected to see a doubling of plastic leakage (from 3.5 Mt to 7.1 Mt by 2050), driven by strong growth in LMIC in particular. China is projected to remain the largest individual contributor to leakage, though with a declining relative share in the region.
Under current policies, aquatic ecosystems are projected to be under growing pressure from plastic pollution. Annual plastic leakage into rivers, lakes and oceans is expected to increase from 3.0 Mt in 2022 to 5.1 Mt in 2050. The vast majority of plastics initially enter freshwater bodies, especially rivers, with significant shares rapidly sinking to river or lake beds (2.7 Mt in 2050) and another 1.9 Mt floating in rivers.
The cumulative burden, including historical flows, is expected to be significant: by 2050, rivers and lakes are projected to hold 126 Mt of plastics, more than doubling the amounts estimated for 2022. Ocean accumulation is also projected to more than triple from 2022 levels, reaching an estimated 55 Mt by 2050.
Rivers and ocean currents transport leaked plastics across countries and regions, with lower middle-income ASEAN countries receiving the highest share of leaked plastics travelling to their coastlines. High- and upper middle-income ASEAN countries and China are important sources of these flows. These patterns are projected to persist through 2050, highlighting the urgency of regional co-operation and shared ambition.
Greenhouse gas (GHG) emissions from the plastic lifecycle are projected to almost double for APT countries, increasing from 0.6 GtCO2e in 2022 to over 1.0 GtCO2e in 2050, mainly driven by continued demand for primary plastic production.
Chapter 4 comprehensively assessed projected trends in plastics use, waste generation and end-of-life fates in the ASEAN Plus Three (APT) region through 2050, under current policies (Baseline scenario). This Chapter complements the analysis by providing an overview of environmental impacts under current policies, including projections for plastic leakage to the environment, implications for aquatic pollution (including leakage to freshwater and oceans, accumulated aquatic pollution, and transboundary flows), as well as plastics-related GHG emissions.
Under current policies, the APT region is projected to remain an important source of plastic leakage to the environment. Figure 5.1 presents this evolution for the 2022-2050 period. The leakage of plastics to the environment in APT countries is projected to increase by 68%, from 8.4 Mt in 2022 to 14.1 Mt in 2050. While this is a substantial increase, it is significantly smaller than the expected doubling in waste generation (from 113 Mt to 242 Mt), reflecting some progress in waste management (see Chapter 4 for a discussion on expected improvements in waste management under current policies). As a result, the share of the APT in global leakage is expected to decrease slightly, from 38% to 35% during the same period (while their share in the global population is projected to decrease from 29% to 24%).1
Trajectories of plastic leakage vary sharply across APT countries. Leakage in ASEAN is projected to double, from 3.5 Mt in 2022 to 7.1 Mt in 2050. This is driven in particular by growth in lower middle-income ASEAN countries (Indonesia and Rest of ASEAN – LMIC), where leakage is projected to more than double (from 1.8 Mt in 2022 to 4.0 Mt in 2050). Leakage is projected to slow down in Thailand by 69% (from 0.37 Mt in 2022 to 0.11 Mt in 2050) thanks to improvements in waste management, but to increase in the rest of high- and upper middle-income ASEAN countries (Rest of ASEAN – HIC & UMIC) by 34% (from 0.6 Mt in 2022 to 0.8 Mt in 2050). In China, the leakage of plastics would continue to increase, from 4.9 Mt in 2022 to 7.0 Mt in 2050, but at a pace slower than economic growth. The plastic leakage of Japan and Korea is projected to remain low, below 0.03 Mt annually, reflecting mature waste management systems.2
Leakage of plastics in million tonnes (Mt).
Notes: The APT grouping includes 11 non-OECD countries and two OECD countries (Japan and Korea). “Rest of OECD” includes 36 of 38 OECD countries (excluding Japan and Korea). “Rest of non-OECD” includes all other countries.
Rest of ASEAN – LMIC includes Cambodia, Lao PDR, Myanmar, Philippines, Viet Nam; Rest of ASEAN – HIC & UMIC includes Brunei Darussalam, Malaysia, Singapore.
Source: OECD ENV-Linkages model, adapted from (OECD, 2022[1]).
While plastic leakage contributes to pollution in all environmental media, implications for aquatic environments are of particular interest due to the high potential for environmental and economic damages in the APT region.
Aquatic ecosystems in the APT are under growing pressure from plastic pollution (see Chapter 2): without urgent action, the flow of plastics to rivers, lakes and oceans will continue to rise, amplifying long-term risks to biodiversity, fisheries, ocean-based economies, livelihoods and human wellbeing. As show in Figure 5.2, annual leakage of plastics to aquatic environments from the APT is expected to increase from 2.9 Mt in 2022 to 5.1 Mt in 20503, despite a slight reduction in the share of the APT in global aquatic leakage (in line with expected trends for overall leakage to the environment).
Similarly to 2022 dynamics, one-half of plastics entering aquatic environments (5.1 Mt) rapidly sink to the bottom of rivers and lakes, 1.9 Mt is expected to remain floating in rivers, and the rest to enter oceans (of which 1.3 Mt from rivers), in 2050. The cumulative burden, including historical flows, is expected to be significant: by 2050, rivers and lakes are projected to hold 126 Mt of plastics, more than doubling the amounts estimated for 2022. Ocean accumulation is also projected to more than triple from 2022 levels, reaching an estimated 55 Mt by 2050. There are long delays from leakage to the final accumulation of stocks, especially in oceans. Thus, even if leakage slows down, aquatic flows remain high and ocean accumulation will continue to increase for a long time.
Plastic leakage to aquatic environments in the APT region in million tonnes (Mt), Baseline scenario
Source: Adapted from (Borrelle et al., 2020[2]; Meijer et al., 2021[3]), based on OECD ENV-Linkages model.
All APT countries contribute to aquatic leakage and pollution, but at different scales and speeds.4 China is projected to remain the largest contributor, accounting for roughly one-half of total annual flows, due to its size, high plastic intensity of economic activity, significant volumes of total leakage of plastics to the environment, and its geographies (with several major rivers). The fastest growth in aquatic plastic flows is expected in ASEAN (as described in Annex Figure 5.A.1), amplifying pollution in freshwaters and oceans and the associated risks. Plastics leaking from ASEAN to aquatic environments annually are expected to double from 1.4 Mt in 2022 to 2.8 Mt in 2050. The fastest growth is projected in particular in ASEAN LMIC (Indonesia and Rest of ASEAN – LMIC). In contrast, in Japan and Korea levels of mismanaged plastic waste and aquatic plastic leakage are projected to remain at low levels (contributing less than 1% of the APT total in both 2022 and 2050).
Geographical features influence where and when plastics enter aquatic environments, as described in Figure 5.3. Freshwaters, and in particular rivers, represent the major first point of entry for plastics in aquatic environments across countries. However, In Indonesia and other ASEAN countries with extensive shorelines, a higher proportion of plastics enters oceans directly from the coasts, compared to rest of the APT (or the rest of the world). In contrast, in China, by 2050 only 19% (18.0 Mt) of total plastic leakage is projected to accumulate in the ocean, with the rest in rivers and lakes. These differences shape not only pollution patterns but also the feasibility of recovery and the choice of effective points of intervention for remediation efforts.
The accumulation of plastics in aquatic systems is compounding. Including historical leakage to aquatic environments, water bodies in the APT are projected to hold a total of 180.9 Mt of plastics by 2050, representing 40% of the global total stock in freshwaters and oceans. Focusing on ASEAN specifically, about 48.1 Mt of plastics are projected to accumulate in rivers and lakes by 2050, while plastics in oceans in ASEAN would increase four-fold, reaching 35.7 Mt in 2050 (from 9.8 Mt in 2022; including due to leakage that occurred in neighbouring countries and regions, as discussed further below).
Values in million tonnes (Mt) by region of origin for the Baseline scenario.
Note: Rest of ASEAN – LMIC includes Cambodia, Lao PDR, Myanmar, Philippines, Viet Nam; Rest of ASEAN – HIC & UMIC includes Brunei Darussalam, Malaysia, Singapore.
Source: Adapted from (Borrelle et al., 2020[2]; Meijer et al., 2021[3]), based on OECD ENV-Linkages model.
While the absolute values of plastic leakage are important to measure environmental impacts, the intensity of leakage (per capita and per GDP) are also helpful indicators to be able to compare across countries, isolating trends in leakage from demographic and economic growth. Table 5.1 presents both metrics for 2022 and 2050. While China is by far the largest source of leakage, it is not the most intensive either in per capita terms or per unit of GDP output. The highest intensity in aquatic leakage is in Rest of Asia – LIC, followed by Rest of Asia – HIC & UMIC.
Per capita aquatic leakage levels are projected to keep increasing overall, faster than the global average. The country projections tell a more nuanced story. While per capita leakage grows for China and ASEAN countries, Thailand stands as an exception, which stems from the improvement is waste mismanagement rates (see Chapter 4). In contrast, the intensity per GDP shows a net decrease, which brings the region close to the current global average, as GDP grows much faster than leakage (and population).
Note: Rest of ASEAN – LMIC includes Cambodia, Lao PDR, Myanmar, Philippines, Viet Nam; Rest of ASEAN – HIC & UMIC includes Brunei Darussalam, Malaysia, Singapore.
Source: Adapted from (Borrelle et al., 2020[2]; Meijer et al., 2021[3]), based on OECD ENV-Linkages model.
Plastic pollution is transboundary in nature; for instance, plastic leakage to freshwaters and oceans originating in one country can travel across borders to neighbouring countries and regions. Once in coastal waters, plastics can be transported across vast distances by ocean currents, washing up on the shores of other countries, often far from the source, as shown in Figure 5.4.
Lower middle-income countries are the largest recipients of plastic leakage originating in other countries. For instance, more than half of the plastics leaked from the coasts of China and high- and upper middle-income ASEAN countries are estimated to reach ASEAN LMIC shores, and this trend is projected to remain constant through 2050. Indonesia, already struggling with domestic plastic leakage, is a major recipient of plastic waste from foreign coasts, especially from neighbouring ASEAN countries (ASEAN – HIC & UMIC). The high flows from other countries to the ASEAN LMIC contrasts with the smaller flows of plastic originating in the coasts of these countries that is transported to other APT countries (although ASEAN LMIC do contribute to flows of plastics to the coasts of the rest of the world). These dynamics are expected to persist through 2050.
Plastic leakage traveling between countries in million tonnes (Mt) in 2022, Baseline scenario
Note: Panel A excludes intra-regional flows. The value indicated by the bars in Panel B shows the domestic flow of plastic leakage—that is, the plastic leakage emitted and received within the same region. Meanwhile, the intervals in each region show the maximum and minimum values of international flows (traveling to different regions) of plastic leakage emitted by each region. These serve to compare how large the domestic flows are in relation to the international flows. For example, in Japan & Korea, the flows of plastic leakage to other regions are minimal compared to the flows that stay within the same region.
Rest of ASEAN – LMIC includes Cambodia, Lao PDR, Myanmar, Philippines, Viet Nam; Rest of ASEAN – HIC & UMIC includes Brunei Darussalam, Malaysia, Singapore.
Source: Adapted from (Borrelle et al., 2020[2]), (Meijer et al., 2021[3]) and (Chassignet, Xu and Zavala-Romero, 2021[4]), based on OECD ENV-Linkages model.
In the absence of additional policies, the accumulation of plastics in coastal areas is projected to rise steadily by 2050 (Figure 5.5). This increase is particularly pronounced for flows reaching the coasts of the rest of ASEAN - LMIC from China and the rest of the world, or from ASEAN – HIC & UMIC to Indonesia. This highlights an environmental justice issue: the countries least equipped to manage the impacts are bearing the greatest burden.
Plastic leakage traveling between countries in million tonnes (Mt), Baseline scenario
Note: The table reads from line (emitting region) to column (receiving region). Rest of ASEAN – LMIC includes Cambodia, Lao PDR, Myanmar, Philippines, Viet Nam; Rest of ASEAN – HIC & UMIC includes Brunei Darussalam, Malaysia, Singapore.
Source: Adapted from (Borrelle et al., 2020[2]), (Meijer et al., 2021[3]) and (Chassignet, Xu and Zavala-Romero, 2021[4]), based on OECD ENV-Linkages model.
The international transport of plastic leakage reaches many oceans and countries in the world, and the lower middle-income countries seem particularly at risk within the APT region. Figure 5.6 presents the international transport of aquatic leakage. The flows of plastic leakage travel significantly between countries. The flows from ASEAN countries (in purple) reach not only ASEAN countries (mostly received in lower middle-income countries as seen in Figure 5.5) but many countries on the coast of the Indian Ocean, especially on the Southeastern coast of Africa. The flows of the Plus Three countries (in red, predominantly from China) reaches many a coast in ASEAN countries (again mostly received in lower middle-income countries as seen in Figure 5.5), but a large band extends across the Pacific Ocean (which would spread wider in time). Finally, the flows from the Rest of the world travel widely in all the oceans on the globe, ubiquitous in all the oceans and reaching many coasts, including the ASEAN and Plus Three countries (again mostly received in lower middle-income countries as seen in Figure 5.5).
International transport of plastic leakage
Note: The map shows where travel distances and concentrations for each location of plastics over a 5-year period, originating from ASEAN countries in purple, Plus Three countries in red and the Rest of the world in orange.
Source: Adapted from (Lebreton, Egger and Slat, 2019[5]), based on OECD ENV-Linkages model.
Under current policies, GHG emissions from the plastic lifecycle are projected to nearly double in APT countries, from 0.6 Gt CO2e in 2022 to over 1.0 Gt CO2e in 2050.5 This is aligned with projections for the global level. This increase is mainly driven by continued increases in primary plastic production, as well as improved waste collection and management. In comparison, global emissions are projected to increase slightly faster in the same time period from 1.9 to 3.3 Gt CO2e. Figure 5.7 show that the share of production and conversion, and end-of-life stages seem to remain roughly constant over time and are similar for APT countries and globally (with the caveat of the unavailability of data at local level).
Total GHG emissions are projected to keep growing in the Baseline scenario in APT countries from 18 GtCO2e to 20 GtCO2e (with a fall in the global share from 36% in 2022 to 30% in 2050, as shown in Annex Figure 5.A.3). As a consequence, the share of plastics in APT GHG emissions soars from 3% in 2022 to 5% in 2050. This growth in the plastic share in GHG emissions is of the same order of magnitude as the global one shown in (OECD, 2022[1]), showing that while global efforts are slowing down the growth in GHG emissions, plastics remain a fast growing source.
GHG emissions from the plastic lifecycle in gigatonnes of CO2 equivalent (GtCO2e), Baseline scenario
Note: End-of-life includes recycling, incineration, landfilling and mismanaged waste.
Source: OECD ENV-Linkages model.
Plastic leakage to aquatic environments in the ASEAN region in million tonnes (Mt), Baseline scenario
Source: OECD ENV-Linkages model, based on (Lebreton, Egger and Slat, 2019[5]).
(Macro)plastic leakage to aquatic environments in million tonnes per year (Mt), Baseline scenario
Note: High and low correspond to high and low emission probability ranges.
Source: Adapted from (Lebreton and Andrady, 2019[6]), based on OECD ENV-Linkages model.
GHG emissions in GtCO2e, Baseline scenario
Note: The figures exclude emissions from land use, land use change and forestry (LULUCF).
Rest of ASEAN – LMIC includes Cambodia, Lao PDR, Myanmar, Philippines, Viet Nam; Rest of ASEAN – HIC & UMIC includes Brunei Darussalam, Malaysia, Singapore.
Source: OECD ENV-Linkages model.
References
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← 1. This compares to, for instance, an 9% increase in the contribution of Sub-Saharan Africa (from 16% of global leakage in 2022 to 25% in 2050) and a 3% increase in the contribution of India (from 10% of global leakage in 2022, to 13% in 2050).
← 2. The remaining leakage in these countries is from e.g. uncollected litter.
← 3. There are uncertainties around the annual plastic leakage into aquatic environments, due to the complex nature of these plastic flows and data limitations. Projections fall in the range of 4.2 to 5.8 Mt for the year 2050.
← 4. Note that these projections are for leakage by country of origin. The destination of the leaked plastics may be in other countries as they travel through the marine environment.
← 5. These calculations are done following the estimate of the Global Plastics Outlook (OECD, 2022[1]). The emissions presented are estimated using global emission coefficients, since plastics-related lifecycle emission coefficients are only available at global level, due to limited availability of data.