Ocean Pollution Requires Different Rules for Different Sources
Plastic waste, oil and radioactive materials enter the ocean through different pathways, so no single policy can manage all three.
Source control prevents pollution before release, while preparedness and clean-up reduce damage after an incident.
International agreements are strongest when obligations are specific, monitoring is possible and states have the capacity to enforce them.
Note
Effectiveness should be judged by compliance and environmental outcomes rather than the number of agreements signed.
A rule may have wide membership but still leave major land-based sources or weak enforcement outside its reach.
Plastic Controls Struggle With Diffuse Land-Based Waste
Definition
Microplastics
Microplastics are small plastic particles, typically less than 5 millimeters in diameter, that result from the breakdown of larger plastic waste or are intentionally manufactured at that size.
Sources and Consequences
Single-use packaging, lost fishing gear and poorly managed waste break into smaller fragments but do not biodegrade quickly.
Ocean currents and gyres concentrate floating debris, while denser particles sink or enter sediments.
Marine organisms can ingest or become entangled in plastics, transferring particles and chemicals through food webs.
Strengths and Weaknesses of Management
MARPOL Annex V bans ships from disposing of plastics at sea and gives ports and flag states a common rule.
Its weakness is that much plastic reaches the sea from land, outside a treaty focused on ships.
Product bans, deposit-return schemes and producer responsibility target plastics before they become waste.
Their weakness is uneven coverage, product substitution and limited waste services in some places.
UN negotiations were still working toward a legally binding instrument covering the full life cycle of plastics in 2026.
Common Mistake
The Great Pacific Garbage Patch is a zone with unusually high debris concentrations, not a solid island of rubbish.
Most particles are dispersed through the water and vary over time with currents and wind.
Oil Rules Combine Prevention With Emergency Response
MARPOL Annex I sets technical and operational rules to prevent oil pollution from ships.
The OPRC Convention requires national response systems, shipboard emergency plans, reporting and international cooperation.
These rules are strong because they connect vessel standards with contingency planning, equipment, training and mutual assistance.
They remain limited because inspections and enforcement vary, offshore production has separate risks, and clean-up cannot restore every damaged habitat.
Example
The 2010 Deepwater Horizon spill showed that response capacity can contain some oil but cannot prevent ecological and livelihood losses after a large deep-water blowout.
The case supports prevention, liability and preparedness rather than reliance on clean-up alone.
Radioactive-Waste Rules Are Narrow but Clear
The London Convention controls deliberate dumping of waste at sea, and a 1993 amendment banned sea dumping of low-level radioactive waste from 1994.
The London Protocol uses a stricter approach in which dumping is prohibited unless a material appears on an approved list.
The strength is a clear international prohibition on a defined disposal route.
The weakness is that accidents and land-based releases require other national and international controls.
Long-lived radionuclides can remain hazardous and move through currents, sediments and food webs, so monitoring must continue after release.
Exam technique
Match each initiative to the pollution pathway it controls.
Then test its geographic coverage, enforcement, capacity demands and ability to prevent rather than only respond to harm.
The Strongest Strategy Acts Upstream
Prevention usually costs less and protects more habitats than removing pollution after it disperses.
Monitoring and liability make rules credible by detecting breaches and assigning clean-up costs.
Regional cooperation is essential because currents carry pollutants across jurisdictional boundaries.
Global rules and local capacity must work together because a treaty cannot replace waste collection, inspections or emergency equipment.
Active recall
Why does MARPOL Annex V address only part of the plastic-pollution problem?
How do MARPOL Annex I and the OPRC Convention perform different roles?
What disposal route does the London Convention prohibit for radioactive waste?
Name two criteria for judging whether a pollution initiative is effective.
