- In late August of 2022, the sea turtle conservation team of Osa Conservation in Costa Rica noticed a significant increase in plastic debris, mostly drink bottles, arriving on the beaches they patrol.
- An analysis revealed the region of their manufacture to mostly be East Asia, and the manner of their arrival suggested that this was a deliberate dumping of the plastic waste near Costa Rica, not from somewhere across the Pacific.
- This kind of illegal dumping activity has been documented elsewhere: “We need to find better ways to enforce internationally agreed laws such as MARPOL Annex V, which bans the dumping of plastics at sea,” a new op-ed argues.
- This post is a commentary. The views expressed are those of the author, not necessarily Mongabay.
The Pacific coast of the Osa Peninsula in Costa Rica is one of the most remote destinations in the country, and the whole of Central America. The peninsula, which is largely composed of the renowned Corcovado National Park, has the largest remaining tract of Pacific lowland wet forest in Mesoamerica, and harbors 2.5% of global terrestrial biodiversity.
In late August of 2022, the sea turtle conservation team of Osa Conservation noticed a significant increase in ocean debris arriving on the beaches of Piro and Pejeperro. The debris accumulated in a short period of time, no more than several days. After this event, the rate of debris accumulation returned to more normal levels. An analysis of this debris determined that the majority of the items were water bottles manufactured in Asia within the last one to two years, however other unusual debris such as large pieces of melted plastic, a large (and fortunately, sealed) container of used motor oil, hiking boots, and a soccer ball were also found.
Osa Peninsula beaches regularly receive flows of plastic water bottles and other debris, but rarely do the majority of them originate from outside of the Americas, furthermore it is rare for relatively clean and recently manufactured bottles to arrive in such a large quantity. The nature of these water bottles, their age, relative cleanliness, and point of origin suggest that they were dropped by a ship somewhere close enough where local currents could bring them ashore to the remote beaches of the peninsula.
Studies of ocean debris in other remote parts of the world have shown the exact same water bottle types and manufacturers with similar ages drifting ashore. Since 1989, the dumping of plastics by ships was made illegal under international law by The International Convention for the Prevention of Pollution from Ships (MARPOL) under Annex V.
However, recent studies of ocean debris, as well as the event described in this analysis, suggest that the deliberate dumping of debris may still be taking place illegally throughout the world’s oceans. Attention needs to be brought to this issue as the possibility that global laws and regulations are not being followed poise a serious threat to the global environment including the health of humans and other living creatures.
A closer look at the bottles
During this debris event, it was evident by simply walking on Piro and Pejeperro beaches that a significant amount of the plastic bottles contained logos and text in East Asian script. In order to better understand the significance, bottles from a beach cleanup were segregated and analyzed.
A simple beach cleanup on the 28th of August, 2022, conducted by two individuals along 2 km (almost one mile) of Pejeperro Beach yielded 364 individual plastic bottles, as well as 5.5 kg (12.12 pounds) of non-recyclable debris. Among these 364 plastic bottles, 214 (or 59%) were identified as having East Asian origin: by far the most common type was water bottles, and the most common manufacturer was Master Kong of China.
These bottles have a characteristic blue cap and blue label. Virtually every plastic bottle of East Asian origin was Chinese. Other major Chinese manufacturers of collected water bottles included Nongfu Spring and Wa Ha Ha. A variety of Chinese specialty drinks and chemical plastic bottles made a significant portion of the collected debris.
There are two main tools for dating these water bottles: reading the printed dates and observing the wear and tear of the plastic, as discussed in detail in some studies on ocean debris. There are no clear standards on the requirements for printing dates and their specific meaning. For example, the U.S. Food and Drug Administration does not require any dates to be printed on plastic water bottles, however most U.S. producers print the date they anticipate the plastic to begin to change the taste of the water it contains. But it is commonly understood that the dates on Chinese-manufactured water bottles signify the date of production. This implies that some of the bottles such as the Wa Ha Ha bottle collected and shown in the image below managed to find their way to Costa Rica from China in less than a year.
We must ask the question: how realistic is it for a plastic water bottle to make such a journey from East Asia to Central America in such a short time?
Can we prove these plastic bottles were dumped at sea?
It is well known that garbage is commonly thrown overboard from vessels at sea in violation of MARPOL regulations. Some recent high-profile examples include a bulk carrier caught dumping garbage over the Great Barrier Reef, and Carnival Cruise Lines being fined $20 million for dumping plastic waste into the ocean. Although a victory for those who advocate for cleaner oceans, these events of law enforcement are quite rare, despite the abundance of evidence that debris dumping at sea is common.
But is there a problem of systematic illegal trash dumping at sea? Several studies suggest that there may be a more organized effort to remove excess debris via ocean going vessels.
Advanced computer modeling that predicts the transportation path and time for floating debris to move through the world’s oceans suggest that the ocean currents do not favor the movement of floating debris to be transported from East Asia to Central America. The major currents in the tropical Pacific go from east to west, and furthermore, a significant amount of floating debris would get sucked into specific areas far from the continents, such as the “Great Pacific Garbage Patch.” The relatively recent manufacturing date of the discovered plastic bottles suggests that these bottles were dumped at sea, and likely not too far from Costa Rica.
Research led by Professor Peter G. Ryan of the FitzPatrick Institute of African Ornithology, as well as eco-activist and serial beach-cleaner Colleen Hughson of Portland, Australia, have shown the same and similarly aged Master Kong and Nongfu spring water bottles as were found during this event in Costa Rica were also found on beaches in Australia, Africa, as well as the island archipelago of Tristan da Cunha in the middle of the Atlantic Ocean. Hughson has started a Facebook Group named “Bottles Overboard” to get the local community involved, and has had some success in identifying and prosecuting vessels at fault. Bottles Overboard has also developed a fantastic video explainer of foreign water bottle pollution.
Based on the evidence of this event, it is difficult to not conclude that the debris originated from a passing vessel, and one can only speculate that it could have been one passing through the Panama Canal. Perhaps this garbage was dumped deliberately prior to passing the canal and the inspections that occur during the process. Although we likely do not have enough data to know which vessel dumped this debris, it is important to understand that it likely did come from a vessel, and we should be increasing our knowledge and understanding of these events so that in the future we can work with the proper authorities to track and prosecute these illegal activities.
What can we do?
Despite pessimistic statistics on plastic pollution affecting the world’s oceans, and even the food we eat, there is much we can do to stem the tide. We need to find better ways to enforce internationally agreed laws such as MARPOL Annex V, which bans the dumping of plastics at sea. Implementation of satellite technology can offer promising results to identify offenders, just as they are used today to track oil tankers. We can improve on education of plastic pollution, especially to populations that live near water ways, to respect the destructive effects of plastic pollution and to appreciate the value of a healthy pollution free ecosystem. More studies such as those cited are very helpful to better understand the current state of plastic pollution. Plastic will likely remain an abundant material in the planet for some time but we must not despair, just as the production of plastics has grown exponentially, we have the power to remove it at an exponential rate if and when we choose to tackle the problem in a serious manner.
Saam Shams served as a sea turtle intern for Osa Conservation in Costa Rica during the summer of 2022, currently works as a civil engineer in San Diego, and continues to volunteer for nature conservation efforts.
Banner image: A plastic beverage bottle floats in the shallow waters off of Sand Island in Hawaii. Image by David Slater / NOAA Coral Reef Ecosystem Program Marine Debris Team, 2015.
Friedlander, Alan M., et al. “Nearshore marine biodiversity of Osa Peninsula, Costa Rica: Where the ocean meets the rainforest.” PloS one 17.7 (2022): e0271731.
Ryan, Peter G., et al. “Rapid increase in Asian bottles in the South Atlantic Ocean indicates major debris inputs from ships.” Proceedings of the National Academy of Sciences116.42 (2019): 20892-20897.
Ryan, Peter G., et al. “Message in a bottle: Assessing the sources and origins of beach litter to tackle marine pollution.” Environmental Pollution 288 (2021): 117729.
Ryan, Peter G. “Land or sea? What bottles tell us about the origins of beach litter in Kenya.” Waste Management 116 (2020): 49-57.
Related audio from Mongabay’s podcast: The U.K. also has an illegal waste dumping problem, as documented by Mongabay’s first ‘true eco-crime’ series, listen here: