The marine environment continues to be adversely affected by pollution from land-based and sea-based activities. While land-based activities contribute a higher percentage of marine pollution, pollution from sea-based activities, especially those involving oil spills are often more 'visible' to the general public. Images of wildlife caught in oil slicks or coated in oil never fail to evoke public concern and sentiments over such incidents. In addition to oil spills, chemical spills and discharges, pollution from routine maintenance work on vessels, pollution from ports and harbours, offshore oil exploitation, dumping at sea and dredging activities also contribute to marine pollution from sea-based activities. A lot of focus has also been given to the introduction of exotic species through the discharge of ballast water. Sea-based activities however are relatively better regulated than land-based activities. There is a host of maritime conventions under the purview of the International Maritime Organisation that aim to control pollution from sea-based activities and provide compensation in case of pollution. Similarly, the oil and gas industry are also known for its stringent self-regulatory approach in pollution prevention. Despite these efforts, marine pollution from sea-based activities continues to occur and to threaten the marine environment as highlighted by incidents such as the Erica and Jessica spills in 1999 and 2001 respectively. More recently, another dimension has been added to the discussion over sea-based pollution, that of marine pollution caused by piratical and terrorist activities. This paper examines issues related to marine pollution and the international efforts to address the issue and highlights possible new trends in marine pollution from sea-based activities.

　

Disasters at sea, particularly those involving oil spills and its effects on the environment make good headlines. This tendency embodies the global concern over the dangers which maritime transportation poses to the marine environment. Pictures of wildlife coated in oil are synonymous with the effects of oil pollution on the marine environment. And as the global economy grows, so does the importance of maritime transportation, including of oil which fuels the economic activities of countries worldwide. In 1994 for example, USD 260 billion worth of Japanese trade passed through the major sea lanes of Southeast Asia¹ In addition vessels worldwide transport over 6.5 billion barrels of oil every year.² There are obvious risks associated with such a high volume movement of oil. And this is reflected in the approximately 120,000 tonnes spilled into the sea as a result of accidents. A further 480,000 tonnes are released into the sea through routine tanker operational activities such as tank cleaning and the release of ballast water.³ Balancing the concerns over the protection of the environment and ensuring the efficient of movement of goods by sea has been the preoccupation of organisations such as the International Maritime Organisation (IMO) and countries worldwide.

　

　

The issue however is not as simple as it is often made out to be and is not confined only to sea-bases pollution from oil. There is an increasing concern worldwide over the introduction of alien organisms through ballast water discharges, chemical spills and the carriage of ultra hazardous cargo such as nuclear waste by sea. From another perspective the issues involved also includes economics and environmental protection, the role of countries as prescribed by international law, rights of transit, design of vessels, training and competency of seamen. This paper examines some of the issues related to the protection of the marine environment from sea-based pollution and the efforts to address the problems. The paper also identifies several emerging issues related to maritime transportation and marine pollution.

　

Probably, the most visible side of sea-based pollution is its effects. Oil coated birds and other wildlife, oily seawater and coastlines and tankers breaking up are common visuals associated with sea pollution. Yet there are many factors which often contributed to this end result of a maritime accident as seen on television or across the front pages of newspapers. The report "Safer Ships and Cleaner Seas" describes the situation as one that is complex in nature and involves many players and is affected by many factors. The report provides a catalogue of issues which needs to be considered in the prevention of pollution from vessels such as the human factor; the roles of the various players in the shipping industry (including that of flag states and port states); and the availability of adequate waste reception facilities. Equally important, the report suggested several possible avenues for reducing the risk of pollution from ships such as better port state and flag state control; the inculcating of a safety culture among the ship crews; and minimising the generation and disposal of wastes from vessels.⁴ This report while meant for a United Kingdom audience has far reaching recommendations for the shipping industry as a whole and had some very pertinent recommendations which could be adopted in a different setting.

　

Human error has been identified by several studies as a major contributing factor to marine pollution from maritime transportation. The International Maritime Organisation (IMO) concluded that more than 90 per cent of marine pollution worldwide is caused by human error which is closely related to matters such as knowledge, training, work specifications, communications and mental or physical fatigue.⁵ These problems are further compounded by questions of economics and profits as shipowners strive for profitability in a highly competitive market at the expense of safety and environmental protection.⁶ Several high profile incidents have been linked to human error, one of which is the Exxon Valdez incident in 1989. To partly address the problem the IMO has made it compulsory for all vessels to have only crews which have been certified according to the requirements of the Standards of Training, Certification and Watchkeeping Convention 1995. The STCW would in many ways facilitate the standardisation of seamen qualification in an industry that comprises seamen from as many as 43 countries with different training, culture and language background and has been implemented in countries which are major providers of seamen such as the Philippines.

　

Pollution at sea is also attributed to the practice of dumping operational wastes from shipping activities at sea. Where oil pollution is concerned, more oil is released into the marine environment from tank cleaning and ballast water discharges than from accidental spills. Added to these are other wastes generated during the day-to-day operations of a vessel such as litter and sewage. In principle, the disposal of these wastes is regulated by the International Convention for the Prevention of Pollution from Ships 1 973 (MARPOL 73/78). In practice, the implementation of MARPOL 73/78 depends on how flag and port states have incorporated the convention into national laws and the subsequent implementation of these national laws. Additionally, a lot also depends on self-regulation by shipmasters and crew especially in areas outside of national jurisdiction such as the high seas. The effectiveness of MARPOL 73/78 in preventing vessel-based pollution is yet to be comprehensively assessed but over 94 per cent of the world tonnage is regulated under MARPOL 73/78 which indicates the significance of the convention to marine pollution prevention.⁷

　

There are also other sources of sea-based marine pollution. In countries where there are large numbers of small fishing vessels, pollution from engine oil has been noted in addition to litter and sewage.⁸ Regulating these sources of pollution may prove to be more difficult given the dispersed nature of small fishing vessels. Oil exploration and drilling activities and natural seepages also contributed to pollution in the marine environment. The amount released however is small compared to oil pollution caused by operational dumping and accidental spills.⁹

　

Wastes from land are also dumped at sea. This form of pollution typically involves the disposal at sea of various types of wastes from industrial as well as domestic sources, wastes from dredging activities, radioactive wastes and until 1991 wastes from incineration at sea. In addition the military sometimes use the sea as a dumping ground for ordinance. In the 1970s the amount of industrial wastes dumped at sea amounted to 11 million tonnes. The figure has decreased to between 4.6 to 6 million tonnes in the 1990s, most of which was dumped by Japan and South Korea.¹⁰ These activities present a completely different challenge to the prevention of marine pollution from oil pollution as a wide variety of wastes could be dumped into the sea with varying effects on the marine environment.

　

The effects of marine pollution can be devastating on marine life and ecosystems. Ecosystems such as coral reefs and mangroves are particularly susceptible to damage from pollution from both sea-based and land-based pollution, particularly oil spills. A number of spills have occurred in areas of ecological significance. The most recent one being the grounding of the Jessica off the Galapagos Islands.¹¹ Other notorious spills in environmentally sensitive areas are the Exxon Valdez spill in the Prince William Sound and the Braer incident in the Shetland Islands.

　

The other side of the situation that does not always appear in the news is the effects of marine pollution on coastal communities In areas such as the Straits of Malacca marine pollution from oil spills could prove disastrous to the 30,000 Malaysian fishermen who depends on the straits for livelihood and also to those who rely on fish resources from the Straits for sustenance. The human dimension of the problem also includes the impact of sea-based marine pollution on economic activities such as tourism and aquaculture.