Marine pollution includes chemicals and garbage. Most pollutants are dumped or blown into the ocean from land-based sources, harming the ecology and well-being of every organism and global economic institution.
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Pollution by Chemicals in Oceans
Numerous chemical contaminants harm the health of the ocean. Various chemicals produce these contaminants, including crude oil and other petroleum products, pharmaceuticals, antifoulants, insecticides, and personal care items. The number of chemicals entering the oceans is thought to have increased by 12% between 2003 and 2022.
Marine pollution is encouraged by the elevated levels of ocean chemicals, such as nitrogen and phosphorus. These chemicals are hazardous to wildlife and humans. Chemical pollution damages the local fishing and tourism sectors because of its harmful effects on human health and the environment.
Types and Effects of Chemical Pollutants in Oceans
Oceans are negatively impacted by oil from spills, discharge, and shipping. Major oil spills in oceans make headlines and are challenging to clean up.
Oil spills have been decreasing recently due to better technologies and regulations. A total of 1.1 million tons of oil were spilled in 1990. This decreased to approximately 25,000 tons by 2015, yet it still accounts for more than 10% of the oil that enters the oceans. The remaining oil waste is discharged into the ocean by rivers, drains, coastal activities, and shipping.
Persistent, bio-accumulative, and toxic pollutants are the most hazardous types of pollutants. Even substances outlawed decades ago, such as polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs), are still significant in deep-sea oceans.
Polar bears, large fish, and other animals can have pollution levels in their bodies that are a million times higher than the water around them.
Endocrine disruptors and teratogens, which affect marine species' capacity to reproduce or lower offspring survival rates, are a significant concern. Particularly cryptic compounds found in personal care products significantly impact ocean health. For instance, it has been discovered that the sunscreen chemical oxybenzone has a detrimental effect on coral health and reproduction.
Nutrient pollution is also problematic for the environment, oceans, and human health. This kind of pollution occurs when human activities, particularly the application of fertilizer on farms, cause chemical runoff into waterways that eventually empty into the ocean.
Algal blooms are encouraged by the elevated levels of chemicals in the coastal water, such as nitrogen and phosphorus, which can be hazardous to marine life.
Algal blooms severely impact the ecosystem and human health, harming the local fishing and tourism sectors.
Harmful Effects of Plastics on Ocean
All manmade items made of plastic that wind up in the oceans are considered marine waste. Plastic from sources on land accumulates due to storm gusts, littering, and poor waste management.
Numerous plastic goods, such as shopping bags, beverage bottles, bottle caps, food wrappers, cigarette butts, and fishing equipment, are common maritime garbage. Plastic waste is particularly harmful, being such a persistent contaminant. The decomposition of plastic products can take hundreds of years.
Ocean life is at risk from this waste. Fish become entangled in the debris, and some animals mistakenly eat things such as plastic bags.
Microplastic, or very small fragments of degraded plastic, is consumed by small creatures who take the chemicals in the plastic and absorb them into their tissues.
Microplastics found in various marine organisms, including plankton and whales, are particles with a diameter of fewer than five millimeters (0.2 inches). The poisonous compounds become a part of larger animals' tissues when they devour microscopic organisms that absorb microplastics. This causes microplastic contamination to move up the food chain and end up in the foods people consume.
Does a Solution For Marine Pollution Exist?
Disposing of hazardous items into the water is currently prohibited by several national laws and international agreements, yet implementing these restrictions is still difficult.
Several pollutants are challenging to eliminate from the environment, and their concentration rises as chemical pollutants migrate up the food chain.
Plastic has been a concern to the marine environment for generations because it is estimated to take hundreds of years to decompose.
Although isolated initiatives to restore estuaries and bays have succeeded, it is hard to completely clear up pollution as it gets trapped in marine sediment. Promoting reuse and recycling can reduce plastic pollution. Light pollution can be reduced at night by dimming superfluous lights. Promoting sensible chemical use through legislative and consumer initiatives helps safeguard the environment in the long run.
Strategies to Reduce Chemical Pollution in Oceans
Preventing pollution before it happens and cleaning up after it is a strategy to reduce chemical pollution. Today's civilization uses a lot of disposable and single-use plastic, including plastic bottles, shipping boxes, and shopping bags. The process of altering society's perspective on chemical consumption is necessary.
The fight against marine pollution lacks viable options. Plastics marketed as "biodegradable" frequently only degrade at temperatures that will never be reached in the ocean. Nevertheless, numerous nations are acting. More than 60 nations have passed laws restricting or outlawing the use of throwaway plastic objects, according to a 2018 study from the United Nations.
Read more: Tackling the Great Pacific Garbage Patch with The Ocean Cleanup Project
References and Further Reading
Kanhai, L. D. K., Asmath, H., & Gobin, J. F. (2022) The status of marine debris/litter and plastic pollution in the Caribbean Large Marine Ecosystem (CLME): 1980–2020. Environmental Pollution, 300, 118919. https://www.sciencedirect.com/science/article/abs/pii/S0269749122001336
Lehtonen, K. K., Bignert, A., Bradshaw, C., Broeg, K., & Schiedek, D. (2017) Chemical pollution and ecotoxicology. In P. Snoeijs-Leijonmalm, H. Schubert, & T. Radziejewska (Eds.), Biological Oceanography of the Baltic Sea (pp. 547–587). Springer Netherlands. https://link.springer.com/chapter/10.1007/978-94-007-0668-2
Scott, D. (2001). Chemical pollution as a factor affecting the sea survival of Atlantic salmon, Salmo salar L. Fisheries Management and Ecology, 8(6), 487–499. https://onlinelibrary.wiley.com/doi/abs/10.1046/j.1365-2400.2001.00277