Litter, waste improperly discarded in public or natural spaces, is a problem impacting ecosystems globally. It involves items from small wrappers to larger discarded objects like tires and electronics. Litter diminishes visual appeal, endangers wildlife, contaminates natural elements, contributes to pervasive microplastic pollution, and presents public health risks.
Harm to Wildlife and Habitats
Litter poses severe threats to living organisms and their natural surroundings. Animals become entangled in discarded items such as plastic bags, fishing lines, and nets. This entanglement causes injuries, suffocation, or restricts an animal’s movement, preventing it from feeding or escaping predators. For instance, over 100,000 marine animals reportedly die annually from plastic litter through entanglement or ingestion.
Animals also frequently mistake litter, especially plastic fragments, food wrappers, or cigarette butts, for food. Ingestion of these items can cause internal injuries, blockages in the digestive system, or lead to starvation as the plastic fills their stomach without providing nutrition. Chemicals within the litter can also poison animals; birds, for example, often ingest brightly colored plastic pieces which can block their digestive tracts.
Large accumulations of litter also degrade and physically obstruct natural habitats. This can render areas uninhabitable for various species, disrupt migration paths, or alter natural processes essential for ecosystem health. Litter can damage or kill plants and contribute to a decrease in biodiversity.
Contamination of Natural Elements
Litter directly pollutes the non-living components of the environment, including soil, water, and air. As litter degrades, it releases harmful chemicals into the soil. These can include heavy metals from batteries, dyes from plastics, or toxins from electronic waste, altering soil pH and nutrient composition. This makes soil unsuitable for plant growth or microbial life and poses risks to human health through direct contact or by consuming plants and animals exposed to toxins.
Litter, especially plastics, chemicals, and organic waste, enters waterways through runoff or direct dumping. This leads to chemical pollution, reduced oxygen levels, and physical blockages, impacting aquatic ecosystems by introducing foreign substances and reducing water quality. For example, cigarette butts contain toxic chemicals that leach into water within an hour of contact.
Improper burning of litter, particularly plastics and other synthetic materials, releases toxic fumes, particulate matter, and greenhouse gases into the atmosphere. This contributes to air pollution and can lead to respiratory problems in humans. Researchers estimate that over 40% of the world’s litter is burned in the open air, releasing these harmful emissions.
Pervasive Microplastic Pollution
Microplastics are tiny plastic fragments, typically less than 5 millimeters in size, that result from the breakdown of larger plastic litter or are intentionally manufactured. Larger plastic items degrade over time due to sun exposure, erosion, and physical abrasion, leading to the widespread presence of microplastics. These microscopic particles are now found throughout oceans, soil, and air, and even within living organisms.
Microplastics are ingested by a wide range of organisms across the food chain, from plankton to larger marine animals. Once ingested, they can cause physical damage, accumulate within tissues, and act as carriers for adsorbed toxins from the environment. These toxins can then be transferred to organisms that ingest the contaminated prey, leading to bioaccumulation and bioamplification within food webs. The long-term persistence and global distribution of microplastics make them a significant environmental concern.
Risks to Public Health
Accumulated litter creates breeding grounds for pests such as rodents and insects like mosquitoes and flies. These vectors can transmit various diseases to humans, including dengue, Zika, and chikungunya, as stagnant water in discarded items provides ideal mosquito breeding habitats. Litter can also harbor bacteria and viruses, which can be spread through direct contact or via contaminated water sources.
Chemicals leaching from discarded items, such as medical waste, industrial chemicals, or heavy metals from electronics, pose a risk of direct exposure to humans. Contaminated water and food sources can also expose humans to these hazardous substances. For example, microplastics found in fish and shellfish consumed by humans raise concerns about long-term health impacts.
Litter also presents immediate physical dangers. Sharp objects like broken glass, metal, or discarded needles can cause injuries. Bulky items can obstruct pathways, leading to slips, trips, and falls. Furthermore, environmental pollution from litter can contaminate food sources, such as fish ingesting microplastics or crops absorbing chemicals from soil, potentially impacting human consumption through the food chain.