PLASTIC MARINE DEBRIS: Importance to Aquatic Environment and Human Health
ABSTRACT
Over the years the importance of plastics for different purposes especially packaging has been emphasized but its adverse effect on the aquatic environment and human health makes it less desirable. Aquatic animals feed on plastic marine debris and sometimes get a sense of satiety. This false satiety results in starvation as these animals no longer have the need to feed. Most often, tiny plastic materials contain or attract toxic Endocrine-like Estrogen Disrupting Chemicals (EEDC) like Polychlorinated Biphenyls (PCBs) and BisphenolA (BPA) from the environment. These toxic chemicals pass to humans indirectly when they feed on the contaminated fish or other aquatic animals; or directly by exposure to the toxic chemicals in plastics. Hence the need to inform, orient and educate the general public on proper waste management and disposal; and proffer solutions.
Plastics in various forms (bottles, bags, cigarette butts and utensils) make up a category of marine debris; they are non-biodegradable, and persist in the environment for a long period of time. Cigarette butt, a plant based plastic also persist in the environment for a long time. Plastics in the aquatic environment entangle fish and other aquatic animals. The frequent indiscriminate disposals of trash on streets and beaches eventually carried into water bodies (lagoon, rivers, seas and oceans) through run-offs are the major cause of plastic contamination in Nigeria’s waters. There is high rate of diseases in humans as a result of direct or indirect consumption of EEDC like PCBs present or leached from plastics beyond WHO Provisional Tolerable Monthly Intake (PTMI) for dioxins, and PCBs (70 picogram per kilogram of body weight).
Aquatic organisms ingest plastic particles directly in water while humans ingest plastics directly through exposure to toxic chemicals in plastic, or indirectly by feeding on contaminated fish or other aquatics. Controlling of challenges of plastic debris requires effective information and orientation. Highlights of the efforts of Government, Individuals and Non Governmental Organisations towards debris free environments are of paramount importance. Government sets regulations and partners with NGO to raise awareness on management of wastes. Meanwhile, the discarded plastics can be re-utilized for other economic uses without recycling. For instance, in fisheries and aquaculture, the discarded plastic bottle corks can be useful for nitrification of aquaculture waste water while the discarded plastic bottles can be used for building fish farm houses.
