International legal system: Marine pollution

. This research aims to address the environmental concerns of marine pollutions and explores the international legal legislation to regulate the equilibrium in the marine ecosystem. It outlines the impacts of marine pollution on the biodiversity, social economy and the wellbeing and health conditions. Subsequently, a critical assessment of law regulation in marine pollutions/Limitations in the international environmental law regulations; and utilizes the United Nations Convention on the Law of the Sea as a foundation for policy recommendations.


INTRODUCTION
Marine pollution is impacting the ocean ecosystem at a unprecedented rate. Since the mid-twentieth century, environmental issues have evolved into a global problem, whose diffuse and transboundary nature has led to a recognition of the limits of sovereignty and the inadequacy of government capacity, and the international community has begun to look at environmental issues as a whole. The habit and tradition of letting the oceans take in human waste has led to the fact that almost all of the planet's oceans are now filled with litter, from the poles to the equator, from coastal bays to submarine riverbeds. The accumulation of marine litter, and in particular plastic litter, is considered to be a global environmental problem that needs to be addressed, along with many other important issues of our time. Despite the international community's efforts over the last two decades to develop effective mechanisms to combat marine pollution, such as the use of markets, social management and administrative orders. However, the problem of marine litter pollution has not improved, and is tending to worsen. International law is an institutional arrangement of legal rights [6] , obligations and responsibilities that provides a common system and framework for cooperation between states and enables them to conduct international relations in accordance with a commonly agreed 'consent'. In the conduct of international environmental affairs, international environmental law regulates transboundary environmental relations between states through rules, principles and the operation of various norms, usually in the form of international treaties, agreements and international documents such as soft law. * Corresponding author: a 2482516799@qq.com， b 757122973@qq.com, c asderty67rtyasd@gmail.com

IMPACTS OF MARINE POLLUTION
Current plastic products are mainly produced from petroleum, a non-degradable material. It will take hundreds of years for plastic waste to completely degrade after entering the natural environment. In other words, plastic waste will exist in the marine environment for a long time and will weather and degrade into plastic fragments and microplastics under the action of solar radiation and seawater washing [1] . These plastic fragments and microplastics are causing serious damage to the marine environment, society, economy and human health.
About 70% of plastic litter enters the sea floor, 15% floats on the surface and 15% washes up on beaches [8,6] . Firstly, plastic litter floating on the sea surface and beaches not only causes visual pollution of the marine landscape, but also degrades the quality of seawater. Secondly, plastic litter entering the seabed can degrade or destroy the habitat of marine organisms and can entangle marine animals, causing damage or even death, or be accidentally ingested by marine organisms, leading to blockage of their digestive tracts.
The most obvious socio-economic impact of marine plastic litter is the economic damage it causes. In particular, marine fisheries, including marine fishing and mariculture, are an important industry for the economic development of countries around the South China Sea, and the annual loss due to marine pollution is approximately US$69.25 million. In addition, the large amount of floating plastic litter can also damage the ship's power plant and hinder the ship's progress. Plastic debris that settles to the sea floor can form shoals and cause ship strikes. The annual cost of damage to ships, stoppages [3] , port management and emergency operations caused by marine plastic litter to commercial shipping vessels is estimated at US$297 million. In addition, plastic pollution can reduce the aesthetic value of coastal tourism and even its profitability. In Vietnam's world-famous tourist town of Da Nang, for example, thousands of plastic bags and bottles pile up on the beach after each high tide or high wave, making it less attractive to tourists.
The degradation of plastic waste into plastic debris and microplastics in the ocean not only affects marine life, but most importantly, these plastic particles are ingested by marine life and remain in the bodies of these marine organisms, potentially allowing humans to ingest plastic when they consume plastic-contaminated food. The most common are aquatic products such as shellfish, mussels and oysters, which are consumed in conjunction with the ingestion of plastics, ultimately endangering human health. In Indonesia, 28% of fish and 33% of shellfish products assessed for human consumption were found to contain plastic. In 2018, the New York Times reported that microplastic particles of nine different materials were detected in humans, including the most common polypropylene (PP) and polyethylene terephthalate (PET) [92]. In the long run, humans will eventually become "plastic people" in name only. Microplastics entering the human body can aggravate respiratory diseases, increase the risk of heart disease and damage the nervous system.

FRAGMENTATION IN THE LEGAL REGULATION OF MARINE POLLUTION
At a macro level, global international legal instruments dealing with marine plastic litter pollution are fragmented, either addressing only one source of marine plastic pollution or regulating only a specific activity that pollutes the oceans. Existing global-level rules to address marine plastic pollution are scattered across different types of multilateral environmental agreements or non-legally binding legal instruments. NCLOS, GAP and the Honolulu Strategy are marine environment protectionoriented instruments that address the issue of marine plastic litter from the perspective of protecting the marine environment. The London Convention and its Protocols and MARPOL are pollution-oriented instruments, the former regulating the pollution of the oceans by dumping plastic waste and the latter regulating plastic pollution from ships. These international legal documents, although they can provide legal support for the prevention and control of marine plastic waste pollution, do not take the reduction of marine plastic waste pollution as their legislative concept or legislative purpose, and cannot provide a mandatory, authoritative and comprehensive international legislative framework and governance mechanism.
At a micro level, global legal instruments lack a specific international treaty to regulate land-based sources of pollution, the main source of marine plastic litter, and existing governance rules are either limited in scope or not legally binding, and fragmented. UNCLOS proposes to regulate land-based sources of pollution into the oceans, but only contains a simple provision in principle, with specific rules to be implemented by States Parties in their national legislation. Furthermore, there are exemptions and opt-out clauses in UNCOLS that further limit the effectiveness of this most obvious regulation of land-based sources of marine plastic litter. The London Convention and its Protocols only regulate the loading onto ships and intentional dumping of land-based plastic waste at sea, not the dumping of plastic waste in rivers and estuaries. The GAP is a non-binding intergovernmental mechanism that cannot fundamentally stop land-based plastic waste from entering the oceans if countries take action based on their own good intentions. Agenda 21, which provides for the prevention, mitigation and control of marine environmental degradation from land-based sources, also suffers from a lack of legal binding force and is inevitably limited in its effectiveness.
In summary, whether analysed at the macro level or at the micro level, the existing rules for the prevention and control of marine plastic litter pollution reflect a clear fragmentation. International legal instruments on marine plastic pollution prevention and control should comprehensively regulate marine plastic pollution from different sources and coordinate the actions of different stakeholders at international, regional and national levels [109]. This requires greater cooperation and coordination among relevant international legal instruments in combating marine plastic litter pollution, but coordination among them is not easy to achieve due to the lack of uniformity in the purposes, parties and actions of legal instruments to combat marine plastic pollution.

INADEQUATE OF REGULATION AND LEGAL ENFORCEMENT IN MARINE POLLUTION LEGISLATIONS
The Global Environment Report on the Rule of Law, published by UNEP, bluntly states that the lack of full implementation of environmental protection laws and regulations is one of the key challenges to continued environmental degradation. Existing global rules on the prevention and control of marine plastic litter, either due to inconsistent enforcement standards or inadequate disciplinary mechanisms, have not been fully implemented by countries and are not sufficient to prevent acts that lead to marine plastic pollution [9] .
The existing international legal rules on the prevention and control of marine plastic litter pollution are not implemented to a uniform standard. For example, the UNCLOS places an obligation on States Parties to adopt domestic legislation to prevent, reduce and control pollution from six different sources of marine plastic litter. The London Convention, for example, requires parties to take "all practicable steps" to prevent pollution of the marine environment through the dumping of plastic waste. In addition, many countries are reluctant to acknowledge their own plastic emissions, with developed Western countries arguing that it is the uncontrolled discharge of plastic waste into the oceans by developing countries that has led to the current increase in pollution, and developing countries arguing that it is the continued discharge of plastic waste into the oceans by developed countries in the early stages of development that has led to the increase in https://doi.org/10.1051/shsconf/202317403020 , 03020 (2023) SHS Web of Conferences 174 SEAA 2023 pollution, which has to some extent hindered the progress of implementation by countries.
Existing international legal rules on marine plastic litter pollution have inadequate disciplinary mechanisms. MARPOL does not directly provide for disciplinary mechanisms, which are established by States Parties in their national legislation. However, an analysis of some of the countries that have established fines in their relevant domestic legislation under MARPOL is not sufficient to deter offenders. For example, the United States has adopted domestic legislation in accordance with MARPOL, but it has a number of shortcomings and plays a more limited role: first, it is limited in its application. The provisions of the disciplinary mechanism do not apply to non-commercial vessels providing services to the government, warships, and vessels that illegally dump in waters under their jurisdiction without flying their flag and refuse to provide relevant information when inspected cannot be inspected. UNCLOS provides for the prevention and control of marine plastic waste pollution at a macro level, but it is not clear how detailed the laws and regulations enacted by each country to reduce marine plastic waste pollution should be and how the effectiveness of the laws and regulations enacted by a country to reduce marine plastic pollution should be judged [8] . However, there is much room for interpretation as to how detailed the laws and regulations enacted by countries to reduce marine plastic pollution should be, how to judge the effectiveness of the laws and regulations enacted by a country to reduce marine plastic pollution, and how to assess whether the countries have reasonably fulfilled their obligations to prevent and control marine plastic waste pollution, and what international responsibility they should bear for not enacting these laws and regulations. These principles and ambiguities make the obligations set out in the Convention less likely to provide clear normative guidance for combating marine plastic litter pollution [5] .

ABSENCE OF LEGAL LEGISLATION IN THE MARINE POLLUTION
The lack of a legally binding treaty on the prevention and control of plastic waste pollution in the South China Sea makes the legal basis for cooperation on the prevention and control of marine plastic waste pollution very weak and the results are not satisfactory. The current series of declarations, action plans, declarations and other legal documents are highly flexible, but lack the legal force to create the necessary deterrence for countries around the South China Sea to ensure the orderly implementation of regional cooperation in the prevention and control of marine plastic waste pollution. The current action plan on marine plastic waste pollution in the South China Sea provides operational guidelines for neighbouring countries [4] , but it is only a small step in the fight against marine plastic waste pollution and is better than nothing in terms of reducing marine plastic waste pollution at the root. Some countries around the South China Sea have already introduced national action plans or management plans for marine plastic management, with specific targets for reducing marine plastic litter pollution. For example, Indonesia's National Action Plan on Marine Litter 2017-2025 proposes to reduce marine plastic litter by 70% by the end of 2025, while Vietnam's National Action Plan on Marine Plastic Litter Management by 2030 aims to reduce marine plastic litter by 75% by 2025 [2] . However, due to the lack of regional guidelines, countries can only act according to their own standards, without achieving synergies, resulting in uneven results. To reduce the amount of plastic waste entering the oceans by around 23% at a regional level, all countries would need to reduce their marine plastic waste by 80%. Currently, the vast majority of neighbouring countries are focusing on improving solid waste collection and management to combat marine plastic litter pollution, however, improving waste management infrastructure requires significant investment, which is a challenge for low-and middle-income countries [7] . This is why cooperation on marine plastic litter prevention and control in the South China Sea, through the legally binding framework convention on marine plastic litter, is particularly necessary [9] .
Regional cooperation to combat marine plastic litter is more advantageous than global multilateral cooperation or bilateral cooperation between countries. Although global multilateral cooperation includes more participants, the willingness and capacity of each participant to take part in marine plastic litter pollution control varies, making it difficult and time-consuming to form a unified action at the global level. Bilateral cooperation between countries is more focused and easier to reach agreement on, but it is less applicable to the prevention and control of marine plastic waste pollution, which has a transboundary flow [5] . Regional cooperation is easier to agree on because of the common interests of countries, and it can also take into account regional geographic and political factors as well as the actual needs of the countries in the region, thus allowing for more personalized content.

"NATIONS CONVENTION ON THE LAW OF THE SEA" AS A LEGAL FOUNDATION TO LEGAL LEGISLATIONS
The United Nations Convention on the Law of the Sea (UNCLOS) is currently the most effective and direct international treaty regulating the conduct of States in the oceans, with more than 150 States having acceded to it, giving it added authority.
The Convention specifically defines "pollution of the marine environment" in its Article 1, "Terms and Scope".29 As human understanding of marine microplastics grows, marine microplastics meet the Convention's definition of "pollution of the marine environment". The definition of "pollution of the marine environment" has also become more acceptable. It is clear that the discharge and management of marine microplastics is regulated by the Convention.
Firstly, the UN Convention on the Law of the Sea creates an international obligation for international cooperation in the implementation of marine environmental protection activities. What are the obligations? The obligation to cooperate internationally requires States parties to the Convention to strengthen their cooperation with States or with international organisations when drafting and providing for international rules, plans of action or procedures consistent with the UN Convention on the Law of the Sea. International cooperation should be based not only on a global but also on a regional basis, taking into account the regional dimension. It should also be based on a regional basis, taking into account the specificities of the region.This international obligation not only requires States to protect the marine environment, but can also serve as a reference for cooperation between States on marine protection.
Secondly, the United Nations Convention on the Law of the Sea contains detailed provisions on the types of marine pollution sources. In particular, the different sources of pollution in the marine environment are classified into six categories, namely, pollution from landbased sources, pollution from activities on the seabed, pollution from activities in the Area, pollution from dumping, pollution from ships and pollution from the atmosphere. In addition, the United Nations Convention on the Law of the Sea also sets out specific provisions for the prevention and control of these six types of marine pollution by the Contracting States.
Thirdly, the UNCLOS provides more detailed provisions on dispute resolution and offers a variety of solutions to resolve conflicts arising from international marine environmental problems in a peaceful manner. Firstly, the parties to the UNCLOS may settle their disputes by negotiation or mediation, the choice of which method of settlement is left to the agreement of the parties. In addition to the settlement of disputes by agreement between the parties, if there are bilateral or regional agreements between the parties which provide for other methods of dispute settlement, the parties may also choose the means of settlement by negotiation on the basis of these concluded agreements. In addition to moderate means of settlement such as negotiation, the UNCLOS also provides for compulsory settlement procedures. There are four main types of compulsory dispute settlement procedures in the Convention, namely, special arbitration, the International Court of Justice and proceedings before the International Court of the Law of the Sea. The choice of these four compulsory dispute settlement procedures is also at the discretion of the parties, other than that only one or more of these procedures may be applied to the settlement of disputes. Such compulsory settlement procedures provide a strong safeguard for the resolution of marine environmental disputes and are of great importance for cooperation in the protection of the marine environment.

CONCLUSION
The level of marine pollution has its roots in human industrial civilisation. Natural scientific research has shown that the oceans are the ultimate home of pollution from human life and industry. All land-based sources of pollution can eventually be found in the oceans. Since the founding of the United Nations, the oceans have been a focus of attention and concern. Many of the disputes over state power have been over the rights and interests of the oceans, while marine pollution has become a major concern for coastal states and a subject of debate. The enactment of the United Nations Convention on the Law of the Sea (UNCLOS) in 1982 marked a fundamental agreement in international law on the protection of the world's largest body of water, and the conduct of states in the global oceans was not only reflected in the enjoyment of legal rights and interests in the oceans, but also in the assumption of obligations. The United Nations Convention on the Law of the Sea ushered in the era of the rule of law for the comprehensive management of global marine pollution and has been the cornerstone of international law for subsequent cooperation on the oceans among regional states. Guided by the theory of regional governance, coastal states in different regions have also developed different mechanisms for cooperation in marine pollution management, such as regional bilateral and multilateral treaties, and soft law action plans. These mechanisms have provided a platform for combating marine pollution in the region and enhancing cooperation on maritime rights and interests and have also provided a meaningful exploration of institutional models for regional management of marine pollution.