Bottled Water: A Sip to Sick

About 70 per cent of the human body is made up of water, which plays a vital role in delivering oxygen to the brain, transporting nutrients, aiding digestion and regulating body temperature. However, the very water we depend on may contain invisible threats —Nano plastics, plastic particles measuring less than 100 nanometres. Plastics are a part of our everyday lives, and plastic pollution is a growing concern. When plastics break down over time, they can form smaller particles called micro plastics, which are 5 mm or less in length—smaller than a sesame seed. Micro plastics, in turn, can break down into even smaller pieces called Nano plastics, which are less than 1 ìm in size. Unable to be seen with the naked eye, these are small enough to enter the body’s cells and tissues. Previous research has found evidence of plastic particles in human blood, lungs, gut, faeces, and reproductive tissues like the placenta and testes. But the potential health effects of these tiny plastic bits are still unproven and unknown. The small size of nanoparticles has made them especially difficult to detect and study.
Emerging research shows that these plastics have infiltrated our drinking water, raising serious health concerns. Recognising the importance of this resource, the UN declared safe drinking water a fundamental human right in 2010, as part of the Sustainable Development Goals, which aim to ensure universal access by 2030. Yet, as of 2022, around 2.2 billion people lacked access to this basic necessity. Of the primary drinking water sources, such as municipal water supplies, bottled water and household filtration systems; bottled water is the preferred choice for millions, widely perceived as safer as and purer than tap water. However, recent studies reveal that bottled water often contains far more plastic contaminants than tap water, undermining its perceived superiority. The researchers found that, on average, a litter of bottled water included about 240,000 tiny pieces of plastic, far exceeding the levels found in tap water. At that time, detection methods were limited to micro plastics.About 90% of these plastic fragments were Nano plastics. This total was 10 to 100 times more plastic particles than seen in earlier studies, which mostly focused on larger micro plastics.
Plastic bottles, primarily made from polyethylene terephthalate (PET), contribute significantly to environmental pollution through their production, transportation and disposal. The discarded bottles persist in the environment for decades, breaking down into micro plastics (under 5 mm) and Nano plastics. As a result, plastic pollution has escalated into a global crisis, contaminating oceans, rivers and even the most remote ecosystems. Studies have detected microscopic plastics in marine life, soil and even human blood, raising concerns about their presence in the food chain and potential health impacts. The water contained particles of all seven types of plastic. The most common was polyamide, a type of nylon that’s often used to help filter and purify water. An abundance of polyethylene terephthalate (PET) was also detected. This might be expected, since PET is used to make bottles for water, soda, and many other drinks and foods. Other identified plastics included polyvinyl chloride, polymethyl methacrylate, and polystyrene, which is also used in water purification. The method identified millions of additional particles that did not match the seven categories of plastic. It’s not yet clear if these tiny particles are Nano plastics or other substances
However, in January 2024, scientists from Columbia and Rutgers Universities introduced a powerful hyperspectral-stimulated Raman scattering optical imaging platform that is capable of detecting Nano plastics at the single-particle level with high sensitivity and specificity. Published in the Proceedings of the National Academy of Sciences, this study detected Nano plastics in bottled water for the first time, with an average of 2, 40,000 detectable plastic particles per litre — about 90 per cent classified as Nano plastics. These numbers are 10 to 100 times higher than those reported in earlier studies that counted only micro plastics. These contaminants originate primarily from bottle materials, caps and filtration processes used in production. Repeated opening and closing of caps and exposure to heat and sunlight exacerbate the plastic particle release.
The health risks of ingesting these plastic particles are concerning. The minuscule size of Nano plastics, invisible to the naked eye, allows them to enter the bloodstream and accumulate in vital organs. Scientists have identified three primary risks: direct toxicity, chemical leachates and microbial contamination. The toxicity of plastic particles can trigger inflammation and cellular damage. Chemical additives such as phthalates and bisphenols, commonly found in plastics, can disrupt hormones, leading to reproductive and metabolic disorders. Additionally, tiny plastics act as carriers for harmful pathogens, increasing infection risks.
Plastic particles have been detected in human blood, lungs, gastrointestinal tract and even placenta. Micro plastics can infiltrate critical organs, while Nano plastics pose a greater risk as they can cross the blood-brain barrier, potentially contributing to neurotoxicity and cognitive decline. Prolonged exposure to plastic contaminants may increase oxidative stress, raising the risk of cancer, cardiovascular disorders and metabolic disruptions. Research suggests Nano plastics can also alter gut microbiota, affecting immune responses and overall health. Long-term studies are needed to fully understand their effects. Given these risks, is bottled water the safer option? In urban areas, tap water is often a more sustainable and cost-effective alternative, undergoing rigorous treatment, including disinfection, filtration and contaminant-testing. While some municipal systems suffer from aging infrastructure and occasional contamination, tap water in many countries is subject to stricter regulations than bottled water.
To improve municipal water quality, governments must invest in modernising treatment plants, repairing pipelines and addressing contamination issues. Public awareness campaigns can rebuild trust in tap water and promote sustainable consumption habits. On an individual level, switching to reusable water bottles and using home filtration systems can significantly reduce plastic waste and exposure to tiny plastics. Filters used under current regulations generally remove particles larger than one micron, including most bacteria, parasites and some viruses, providing adequate protection against harmful contaminants in many public water sources. High-quality water filters, such as activated carbon or reverse osmosis systems, have been shown to reduce micro plastic levels in drinking water. Community initiatives, such as public water fountains and refill stations, also play a vital role.
Once considered a symbol of convenience, bottled water now presents hidden dangers to both human health and the environment. While it remains a vital resource in regions lacking safe tap water, its long-term risks demand urgent attention. A critical first step is to prevent further contamination of groundwater and surface water sources. Addressing water insecurity through improved municipal systems and sustainable practices is essential to ensuring universal access to safe drinking water. Furthermore, continued scientific research is necessary to uncover the full extent of micro plastic exposure and its biological effects, enabling policymakers to implement stronger regulations for public health and environmental sustainability. By tackling these challenges, we can ensure that safe drinking water is accessible to all, protecting both people and the planet.
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