Plastic, one of the most preferred materials in today's industrial world, is posing serious threats to the environment and consumer's health in many direct and indirect ways. Exposure to harmful chemicals during manufacturing, leaching in the stored food items while using plastic packages or chewing of plastic teethers and toys by children are linked with severe adverse health outcomes such as cancers, birth defects, impaired immunity, endocrine disruption, developmental and reproductive effects etc. Promotion of plastics substitutes, and safe disposal of plastic waste requires urgent and definitive action to take care of this potential health hazard in future.
Every year, the world produces around 430 million metric tons of new plastic. If we proceed on this trajectory, global plastics use is expected to nearly triple by the year 2060.
Microplastics
Microplastics are plastic particles between 0.1 and 5000 µm in size that have attracted considerable attention from the scientific community and the general public, as they threaten the environment. Microplastics contribute to various harmful effects, including lipid peroxidation, DNA damage, activation of mitogen-activated protein kinase pathways, cell membrane breakages, mitochondrial dysfunction, lysosomal defects, inflammation, and apoptosis. They affect cells, tissues, organs, and overall health, potentially contributing to conditions like cancer and cardiovascular disease. They pose a significant danger due to their widespread occurrence in food.
Oxidative stress is an imbalance of free radicals and antioxidants in your body that leads to cell damage. In recent years, information has emerged indicating that microplastics can cause oxidative stress, a known factor in accelerating the aging of organisms.
Single-use Plastic
Of all the plastic we use, 40% is used just once. Every year we use several billion items such as bags, bottles, trays, and food packaging. Supermarkets are full of it. Some people are careless with packaging and leave it behind as litter. But there are also places where people can’t do otherwise because there is no waste collection system. It is without a doubt that even if most people do their best, much of that single-use plastic enters the environment, being one of the biggest causes of plastic pollution.
Other Causes of Plastic Pollution
It is not just about single-use plastic. Often people do not realize that they pollute the environment with plastic. For example, car tires are made of rubber and plastic which wears out while driving. That means that through this friction, thousands of microplastics get released onto the road and in the air.
In addition, machine washing and drying of synthetic clothes let loose millions of microfibers into the drainage system. Personal care products and paint can also contain microplastics that wash away in wastewater. In addition, there is a kind of plastic which is also incorporated into chewing gums.
Cigarette Butts
Cigarette butts consist of filters (made of cellulose acetate, a bioplastic made from wood pulp), fine paper, unburned tobacco remains, ash, smoke residues, and other remains from cigarette combustion. The purpose of the cigarette filter is to capture some of the particulates from the smoke and to dilute substances found in the smoke such as smoke residues, nicotine, and carbon monoxide. It helps smokers handle and stub out the cigarette.
With an average weight of 0.2g per cigarette butt, it amounts to 1.1 million tons worldwide every year. Cigarette butts found on the ground may weigh more, if they have been only partially smoked (some tobacco and paper remaining), and/or if they have been in contact with dirt or humidity.
Cigarette butts can be recycled; however, it would require 1) a wide collection scheme with extensive transports and logistics, and 2) large amounts of water, chemicals, and energy to clean them, which—from an environmental impact perspective—would cancel the benefits of recycling.
When cigarette butts are left in the environment, the sun, rain and wind will ultimately break the plastic filter down into tiny microplastics, releasing the same toxic chemicals onto our beaches and into our waterways.
Marine Plastic Pollution
There are many sources of marine plastics that we know, some of the biggest polluters are: shipping waste, our roads as tires degrade and break down, plastic products which we dispose of in our homes, plastics from industrial waste, and the litter we see on our beaches.
Plastic pollution is one of the biggest threats to the ocean and marine life. While cigarette butts are the No. 1 man-made contaminant in the world’s oceans, they happen to be the least regulated.
Plastic carried by water flows downhill to the sea causing plastic pollution to reach the oceans. Rivers, for example, transport a lot of plastic to the sea. But that’s not the only way plastic moves around; it can also be transported by the wind. Even in gentle winds, plastic, which is very light, blows away – especially from landfill sites where it is dumped.
Plastic does not always float on the surface; it can also sink directly to the seafloor, become caught up in underwater avalanches and mix with sediment flowing down submarine canyons. Plastic that reaches into the deep-sea can end up buried in seafloor sediments in areas that are hotspots for marine life.
Microplastics in the deep-sea eventually accumulate toxins on their surface. This toxin-covered plastic is then eaten by the smallest marine life, which causes it to enter the food chain, becoming consumed by larger marine animals, and subsequently, people.
From the tiniest plankton to the largest whales, plastics impact nearly 700 species oceans. In the ocean, plastic debris injures and kills fish, seabirds and marine mammals. Marine plastic pollution has impacted at least 86% of all sea turtle species, 44% of all seabird species and 43% of all marine mammal species. The impacts include fatalities as a result of ingestion, starvation, suffocation, infection, drowning, and entanglement.
To date, more than 100 million tons of plastic waste are estimated to have entered the oceans. Less than 1 percent is floating at the ocean surface, while 33 percent have been deposited along coasts and on the seafloor. Another 27 percent of plastic waste are in coastal waters and 39 percent are in the open ocean somewhere between the surface and the seafloor. Plastic debris is found everywhere in the oceans, from the surface down to the deep trenches. It is present even in remote areas such as the South Pacific or the Arctic. Around 60 percent of all plastic particles initially float on the ocean surface.
Plastic Pollution Threatens Human Health
Recent evidence indicates that humans constantly inhale and ingest microplastic through contaminated seafood, including fish and shellfish, Additionally, microplastics have been found in tap water, bottled water, and even commonly consumed beverages, such as salt. In fact, a new study estimates that the average adult consumes approximately 2,000 microplastics per year through salt.
Microplastics pose a growing concern as they can cause irritation if small enough to enter cells or tissues. Larger microplastics pose an even greater risk due to their chemical toxicity, which stems from the presence of hazardous substances that interfere with endocrine systems.
Plastic poses risks to human health at every stage of its lifecycle. More recently, microplastics have been found inside the human body: in our lungs, our blood, our feces, the placenta, and in breast milk.
From oil extraction and plastic production to product use, recycling and disposal, harmful substances can be released and disrupt our immune and hormone systems, cause cancers or result in other health impacts.
Microplastics and Lung Health
Breathing plastic particles and associated chemicals causes damage to the lungs. Studies from the last few decades have consistently shown plastic particles found in the lung specimens of patients with cancer and chronic lung disease. Workers exposed to plastic fibers can have lung problems and reduced lung capacity, perhaps due to damage caused by inflammation.
Scientists also know that the chemicals that make up these plastics are toxic to humans at high enough concentrations.
It is not realistic to avoid all plastic particles. While research continues, experts suggest people with a high risk of exposure, such as construction workers or people who work in factories where plastic is made or used, should wear a good mask, wash clothing after work, and generally avoid places where dust is visible. People can reduce their use of plastic by opting to use paper or cloth bags for groceries and by avoiding single use plastic straws, cups, and other food containers.