Plastic is a versatile material composed of polymers, long chains of molecules. Its adaptability allows it to be molded into various forms, making it valuable across industries like packaging, construction, and medical equipment. Despite its utility and properties such as low weight, durability, flexibility, and cost-effective production, the widespread use of plastic presents significant drawbacks that impact the environment and human well-being.
Environmental Contamination
Plastic production, exceeding 400 million tonnes annually, leads to extensive environmental contamination. About 50% of this is for single-use purposes. Approximately 22% of plastic waste is mismanaged, ending up in natural environments instead of being recycled or properly contained.
Plastic pollution is evident in aquatic ecosystems, with an estimated 1 to 11 million tonnes entering oceans annually. This accumulation results in visible debris, known as macroplastics, which threaten wildlife. Seabirds and marine animals suffer injury or death from entanglement or ingestion of plastic fragments. Studies have found plastic in the stomachs of 100% of baby sea turtles.
Plastics break down into microscopic particles called microplastics and even smaller nanoplastics. These fragments persist in the environment for hundreds of years because the chemical bonds in synthetic polymers resist natural decay processes. Microplastics are ubiquitous, found in oceans, rivers, soil, and air, entering ecosystems as they continually fragment.
Depletion of Fossil Resources
Plastic production relies on finite fossil resources, primarily crude oil and natural gas. Over 98% of plastics are derived from these petrochemicals. This demand contributes to the depletion of non-renewable reserves.
Plastic production accounts for 4% to 8% of global oil consumption. Projections indicate this percentage could reach 20% of the world’s oil demand by 2050. This increasing reliance strains global fossil fuel supplies.
Plastic manufacturing is energy-intensive, from raw material extraction to the final product. Processes like injection molding, for instance, can consume 0.9 to 1.6 kilowatt-hours per kilogram of plastic. This energy consumption, largely powered by fossil fuels, leads to greenhouse gas emissions. In 2019, plastic production generated 1.8 billion tonnes of greenhouse gases, representing 3.4% of total global emissions. This figure is expected to grow, contributing to atmospheric changes.
Potential Human Health Impacts
Plastic use raises concerns about human health impacts, primarily due to chemical additives. Substances like phthalates and Bisphenol A (BPA) are added to plastics to enhance flexibility or durability. These chemicals can leach into food, water, and the environment, leading to human exposure.
Phthalates and BPA are endocrine-disrupting chemicals (EDCs). They interfere with the body’s natural hormone systems, mimicking or blocking hormonal actions. Exposure to BPA is associated with disrupted endocrine function, and effects on reproductive health and metabolism. Phthalates have been linked to developmental issues, reduced fertility, and obesity.
Humans are exposed to microplastics through ingestion of contaminated food and water, and inhalation of airborne particles. These fragments have been detected in human tissues, indicating widespread internal exposure. While research into the full scope of their health consequences is ongoing, studies suggest microplastics may contribute to inflammation and altered metabolic processes. Individuals may ingest tens of thousands to millions of microplastic particles annually.