Viet Nam has a long coastline, high population, rapid economic growth, urbanization, and tourism development in recent years. It has a land area of 33,123 thousand hectares (Natural Resources & Environment, 2016) with a coastal length of about 3,200 km, excluding the coastline of islands (Portal, 2018) with approximately 3,450 rivers, streams and 114 estuaries flowing into the sea (M.O.N.R.E., 2015). The total population in Viet Nam was estimated at 94.67 million people in 2018 (General Statistics Office of Viet Nam, n.d.), which is expected to increase by 18% in the period between 2015 and 2030(Bank, 2018). The country has also experienced rapid urbanization. However, the urban infrastructure has still not met the environmental requirements (M.O.N.R.E., 2017).

Viet Nam had relatively high economic growth over the past ten years, with GDP growth increasing from 5.66% in 2008 to 7.08% in 2018Figure 1. Consumer industries, especially those generating plastic waste, are growing. In 2018, total commercial marketing of consumer goods and services were estimated at 4,395 trillion Viet Nam Dong (VND), an increase of 11.7%, compared to that in 2017 (General Statistics Office of Viet Nam, n.d.).

At the same time, Viet Nam tourism is also growing fast. From 2013 to 2018, the number of international arrivals has doubled and the number of domestic tourists increased by nearly 2.3 times; the revenue from tourism industry increased from 200,000 billion VND in 2013 to 620,000 billion VND in 2018 (Viet Nam National Administration of Tourism, n.d.) Figure 2.

The Viet Nam’s plastic sector is growing rapidly increasing from 16% to 18% in the period of 2010 to 2015. The use of plastic products per capita increased nearly 11 times, from 3.8 kg/person in 1990 to 41 kg/person in 2015 (Association, 2015). The industrial and construction plastics account for the high proportion in plastic industry structure. However, plastic packaging had also increased due to the growth of some products such as food and beverages and non-food sectors with an increase from 2.8% to 15.1% (Duong, 2018) (Table 1).

Despite the rapid growth of the plastic industry, domestic plastic raw materials only met 20-25%, the rest was imported (Association, 2015). Plastic scrap imported into Viet Nam increased from 2016 and surged in the first six months of 2018 due to the ban of scrap import of China (Table 2). Besides, the illegal import of waste in the form of plastic scrap also increased; until January 25, 2019, there were more than 24,000 scrap imported containers unclaimed for more than 90 days in all seaports (Nhan Dan Online, 2019).

This paper investigates current issues, challenges, and constraints in managing plastic waste in Viet Nam and makes recommendations for improvement. The authors utilise an unsystematic narrative overview to conduct the research. Such literature review is considered as most appropriate for the type of research required for this study. A narrative overview means the paper will condense information and resources from various sources (eg. Governmental legislations, peer-reviewed journal articles, government and international reports etc) to understand the development of the topic and develop future directions to solve issues, challenges and gaps.

Together with the growing population, rapid urbanization and tourism development, economic growth in general, and the development of plastic industry, the generation of domestic solid waste have been growing in Viet Nam. The total amount of household solid waste was estimated to be 25.5 million tons in 2017, of which urban solid waste contributing to 38,000 tons per day and rural domestic solid waste contibuting to 32,000 tons per day (M.O.N.R.E., 2017). With an average growth rate of 6.6% per year, the total amount of household solid waste is forecast to reach 54 million tons in 2030 (Bank, 2018).

The estimated amount of plastic waste contributed to about 8 to 12% of the total municipal solid waste (Administration, 2018), which is equivalent to 2.04 to 3.06 million tons of plastic waste per year generated. With an average domestic solid waste collection rate of 55% - 65% (Construction, 2017), the amount of non-collected plastic waste was about 0.714 to 1.377 million tons per year. In Phu Quoc island (Kien Giang province), the amount of domestic solid waste is at 155 tons per day, of which 29.5 tons (19%) being plastic waste. Of this volume, only 1.1 tons are recycled by households, 17 tons collected (~ 60%) and 11.4 tons (~40%) are still discharged directly into the environment (Nam, 2018).

According to the statistics of the Ministry of Natural Resources and Environment (MONRE), Hanoi Ho and Ho Chi Minh City generates about 80 tons of plastic waste daily. Hanoi produces around 4,000 to 5,000 tons of solid waste, of which plastic waste accounting for 7-8% while Ho Chi Minh releases about 7,000 tons of waste, of which nylon waste accounting for about 10% (M.O.N.R.E., 2017). This figure is 12.2% - 14.2% for Hai Phong, 6% - 18% for Phu Tho and from 3.4 - 10.6% for other provinces in Viet Nam (Bank, 2018).

Regarding waste collection, by 2018, the municipal solid waste collection was about 85-86% in urban area, but relatively low in rural areas with around 40-55% collection rate. It is estimated that around 8-12% of municipal domestic solid waste is recycled and 70-75% of the collection is landfilled (M.O.N.R.E., 2018). By 2015, there were about 660 landfills in the whole country, with a total area of about 4,900 ha, of which, 203 landfills, (accounted for about 31%) were managed in an environmentally safe manner while the rest were just open dumping sites (Bank, 2018)

There is a significant amount of solid waste, including plastic waste, ending up in open environment as a result of mismanagement. Most of these plastics end up finishing in the sea because plastic waste is easy to follow rivers to the sea, owing to its lightweight under the impact of wind and flow (Bank, 2018). Plastic waste at sea is a significant concern of the world today because of its adverse effects on marine ecosystems. According to a recent study, Viet Nam is ranked fourth country, which contributes to the most significant volume of plastic waste entering the ocean (closely following China, Indonesia, and the Philippines) with around 0.28 to 0.73 tons per year (Jambeck et al., 2015).

The marine pollution caused by plastic waste on beaches and coastal areas and islands in Viet Nam is becoming a major issue. The volume of plastic waste collected is about 8-10m 3 per day from the bays, which belong to Cat Ba archipelago in Hai Phong city; a dozen of tons of plastic waste such as plastic bottle, plastic bag in Do Son beach, etc. (Paper, 2018). The 2018 "Let's Clean the Sea" Campaign, which was held once a week at least one area contaminated by marine debris, has collected 1,282 tons of marine debris (Summary of the Campaign 'Let's Clean the Sea', n.d.). According to many fishermen in the South-Central Area, marine plastic waste in coastal areas is estimated to be three parts of fish and one part of plastic waste (Alarming Plastic Waste in Seafood Exploitation, n.d.).

The marine litter mainly consists of plastic waste generated inland and finiding its way to oceans. Marine litter has become a problem to many countries due to its major impacts on both terrestrial and aquatic ecosystems. Due to this reason plastic waste contamination in open environment is attracting much attention from both researchers, policy makers, and the general public. Since marine organisms can ingest or become entangled plastic waste, marine litter is considered hazardous to the entire ecosystem.

A study conducted on eight regions in the Asia and Pacific Region (between Australia and China) concluded that the likelihood of disease in coral reefs increased to 96%, This would directly affect organisms that colonize these coral reefs for feeding, breeding, etc. For instance, another study concluded that the loss of integrity of coral reefs have reduced fisheries productivity by a factor of 3 (Lamb et al., 2018). A study conducted on the inshore reefs of Australia's Great Barrier Reef revealed coral would often regard microplastics for prey and can consume up to ~50 g of microplastics (Hall et al., 2015), (Hankins et al., 2018).

Ingestion of plastic waste by fish also affects human consumption and consumption by predators, such as birds. Fish samples collected from a market in Makassar, Indonesia, revealed anthropogenic debris in 28% of individual fish and 33% of individual shellfish. This raises a concern about the effects of fish consumption on human well being (Rochman et al., 2015).

Most effects on sea turtles due to marine litter arise from ingestion and entanglement. Ingestion of plastics by these sea turtles causes intestinal blockage, internal injuries, and malnutrition. This ingestion may occur directly or indirectly. There is evidence that juvenile green sea turtles ingest plastics through the consumption of macroalgae (Beneditto APM & DR, 2014). Entanglement remains the most common cause of mortality in sea turtles, causing lacerations, increased drag, which may cause drowning and subsequent death (Nelm et al., 2015). Studies conducted on green sea turtles found that there was a 50% chance of mortality if a sea turtle had 14 pieces of plastic in their gut. It is also suggested that ingestion occurs most frequently in juvenile sea turtles (Wilcox et al., 2018).

In recent years, Viet Nam has issued many policies and legislations to take measures on precaution, prevention, and treatment of solid waste, including plastic waste (Box 1). The country has also established a system of agencies from the central to local level on waste management. Accordingly, the MONRE is the focal ministry to unify the state management of solid waste, in coordination with the Ministry of Construction (MOC), the Ministry of Industry and Trade (MOIT), the Ministry of Agriculture and Rural Development (MARD), the Ministry of Health (MOH) and Provincial People's Committees.

Box 1. Policy and Lesgiations documents on waste management (Government of Vietnam, 2012, 2013, 2015a, 2015b, 2015c, 2015d, 2019)

Regulations on prevention, collection, and treatment of solid waste (including plastic waste)

and will be efective from 1^st January, 2022.

Incentive regulations of environmentally friendly products

Environmentally friendly plastic bags and financial measures to reduce non-biodegradable plastic bags

Regulations on sanctioning administrative violations

Other relevant policies

According to the legislation on solid waste in Viet Nam, waste should be separated at the source, reduced, reused, recycled and treated. Recycling and energy recovery from waste is specially enhanced to limit landfilling. A hazardous waste generator should do registration at environmental agencies, and the waste should be managed only by licensed companies. The Extended Producer Responsibility (EPR) mechanism is applied with products and packaging materials with recycable value for the recycling responsibility of the producers and importers in the Law on Environmental Protection 2020, which has not applied before. With regards to plastic waste, the Law on Environmental Protection Tax 2010 has imposed tax on plastic bags. Besides, Viet Nam is promoting the usage of biodegradable plastic bags in daily life, as well as regulations on certification of this kind of bags.

Firstly, reviewing, building and completing policies and laws on municipal waste management with special focus on plastic waste should be implemented urgently. Plastic waste management based on a circular economy approach should be strictly considered by competent authorities in Viet Nam, which is considered as a good practice in some countries such as Japan, Singapore, France, Netherlands, German, United States, etc, to control the lifecycle of plastic procducts and reduce the emision of plastic waste (Nam & Hanh, 2019). Furthermore, the Government should make the policies and laws to concentrate on recycling, minimizing landfilling and reducing the disposal of plastic waste. The environmental protection tax on plastic bags should be increased; tax on other singleuse plastic products should be imposed. The usage of single-use products should be gradually limited and prohibited by the Vietnamese Government, which is being applied successfully in countries like Belgium, Denmark, Greece, and Israel to reduce the generation of single-use plastic waste (U.N.E.P., 2018). The Government should also develop policies to incentivise the production and use of green products to replace the single-use plastic products. Regulations for EPR to recycle, collect and treat (directly and indirectly) plastic packaging and other plastic products should be detailed and provided enough resources to implement effectively. The Government should specify the responsibilities of stakeholders in the management of plastic waste in oceans.

Secondly, the Government should effectively implement the sorting of domestic solid waste at source, enhance the collection, treatment, recycling, and reuse of solid waste, including plastic waste. The priority should be given to urban areas and residential areas along rivers, coastal areas, and seaports. The regulations improved concerning sorting, collection and treatment of domestic solid waste regulated in the Law on Enviromental Protection in 2020 should be effectively implemented to avoid the mis-management leading to the leaking of the plastic waste into the sea. Apply a landfill tax to ensure competitiveness between landfill with other waste treatment methods; prohibit burying solid waste containing plastic waste in riparian and coastal areas.

Thirdly, the focal agencies of solid waste management at all levels should be MONRE and DONRE. Responsibilities and coordination mechanisms among relevant agencies in solid waste management, including plastic waste, should be specified. Moreover, the Government should strengthen the capacity of management agencies, of which focusing on environmental management officials.

Fourthly, developing feasible strategies, planings, and specific action plans following Viet Nam's practices should be one of priorities. The Government should implement effectively the National Action Plan on Marine Plastic Debris Management by 2030; handle unsanitary landfills; invest in crucial projects on solid waste treatment, which are suitable to the conditions of sub-regions and regions; enhance research and application of modern science and technology in the collection, treatment, monitoring and supervision of marine plastic waste. The investment of Can Tho province in Viet Nam to build a solid waste treatment plant for energy recovery incineration, which treats 70% of domestic solid waste generated in this province, is a good example to apply the other provinces to limit the landfill in Viet Nam (Han, 2020).

Fifthly, the number of national and local environmental inspectors should be increased, and their capacity should be strengthened. Inspection plans should be implemented at provinces/cities to take precaution, preventing and treating plastic waste from land-based activities to restrict disposing of plastic waste into the sea.

Sixthly, promoting and raising awareness of stakeholders on avoiding, preventing, minimizing and treating plastic waste should be enriched. Some local authorities in Viet Nam have applied successfully the involvement of stakeholders to deal with plastic waste problems and Cat Hai district in Hai Phong city is a typical example. In this District, the local authority mobilizes the participation of individuals, travel facicities and social organizations to use environmentally friendly products to replace the plastic products as well as clean the environment (Tan, 2019). Therefore, the success of Cat Hai district should be used to develop the suitable policies to adjust behaviors, habits of using single-use plastic products to familiar with the use of environmentally friendly products. The Government should ensure adequate mechanisms to encourage successful implementation of domestic solid waste management such as sorting at source, limiting plastic waste disposal into the rivers and sea; help stakeholders to effectively implement the slogan: "reducing, reusing and recycling plastic waste".

Finally, international cooperation on marine environmental protection, including reducing and treating transboundary plastic waste at sea should be promoted. Viet Nam should be active in developing a comprehensive regional and global cooperation mechanism, which incorporate programs and projects aiming to coordinate and implement control and reduction of ocean plastic waste.

Marine plastic waste is a global environmental problem. Plastic waste is being present throughout the seas and seriously threatening the marine environment and ecosystem. Globally, Viet Nam is considerd by a recent study as one of the top five countries for plastic waste discharge into the sea. The Government has been working hard to resolve this pressing issue, but there are numbers of limitations and shortcomings in policies and laws; lack of resources for implementation, inspection, examination and handling of violations; limited awareness of stakeholders on marine plastic waste problems.

Therefore, in moving forward, Viet Nam needs to focus on the following isues:

a) To complete the legislations system on waste management by isuing decree and circulars for implementation of the Law on Environmental Protection 2020 on EPR of plastic packaging; ban on plastic bags and certain single-use plasctics and; guidelines for monitoring and management of marine plastic waste. Economic instruments such as tax on landfill, waste volume-based charge (pay-as-you-throw) should be introduced.

b)To successfully implement the National Action Plan on Marine Plastic Debris Management by 2030 through an appropriate funding program to ensure achievements of objectives of the plan. The collection, recycling and treatment of plastic waste should be further strengthened.

c)To continously raise awareness of people and management agencies on marine plastic waste, to implement the national campaign on prevention and reducing plastic waste through which knowledge on plastics and microplastics also to be enhanced.

d)To promote researches and studies on diferrent aspects of marine plastic waste managemnt including recycling technologies, impacts of plastics and microplastics on health and environment, related standards and technical regulations, ect.

e) To promote international cooperation on marine plastic waste management. Viet Nam should proactively participate into development of an international agreement/convention on marine plastic waste and an international center should be estalished in the country.

Being a rising economy in the South East Asia region, Viet Nam is standing in front of a development decade with many opportunities and challenges. In the next 10 years the country should improve its environmental management including successful solutions to resolve the marine plastic waste issue as strongly committed by the government.