Salt And Plastic: A Surprising Combination

Plastic pollution is a pressing global issue, with microplastics—small pieces of plastic smaller than 5mm—found in oceans, tap water, seafood, and wildlife. A recent study has found that microplastics are also present in 90% of table salt brands sampled worldwide, with sea salt having the highest level of plastic contamination. This means that the average adult may be consuming approximately 2,000 microplastics per year through salt alone. While the health impact of ingesting plastic is still unknown, it is important to address plastic pollution and reduce plastic waste to limit our exposure to microplastics.

Microplastics found in 90% of salt brands

A 2018 study published in the peer-reviewed journal Environmental Science & Technology found that 90% of salt brands globally contain microplastics. The study, co-designed by Professor Seung-Kyu Kim of Incheon National University and Greenpeace East Asia, analyzed 39 salt brands from 21 countries, including the US, China, India, the UK, France, and Australia. The findings revealed that sea salt had the highest level of plastic contamination, followed by lake salt and then rock salt.

The study highlights the pervasiveness of plastic pollution in the environment and raises concerns about the potential health impacts of ingesting microplastics through salt consumption. It is estimated that an average adult consumes approximately 2,000 microplastics per year through salt alone. However, the health effects of ingesting microplastics are still not fully understood, and more research is needed to determine the risks associated with this exposure.

The presence of microplastics in salt is attributed to the widespread issue of plastic pollution in the environment. Researchers believe that the majority of the contamination comes from microfibres and single-use plastics, such as water bottles, which comprise the majority of plastic waste. The study also indicated that Asia is a hotspot for global plastic pollution, with Indonesian sea salt samples containing the highest quantities of microplastics.

The findings of this study have significant implications for consumer awareness and the need to address plastic pollution on a global scale. Preventative measures, such as controlling the environmental discharge of mismanaged plastics and reducing plastic waste, are crucial to mitigating the impact of microplastics on human health and the environment.

Plastic pollution in the environment

Plastic pollution is the accumulation of synthetic plastic products in the environment to the extent that they create problems for wildlife, their habitats, and human populations. Plastics are a polymeric material, meaning their molecules are very large and chain-like. Synthetic plastics are largely non-biodegradable, allowing them to persist in natural environments for hundreds of years.

The invention of Bakelite in 1907 introduced the world's first synthetic plastic resins into global commerce. By the end of the 20th century, plastics had become persistent polluters of many environmental niches, from Mount Everest to the Mariana Trench. Plastic pollution can cause significant aesthetic blight and harm wildlife through ingestion or entanglement. Nearly 2,100 species, including endangered ones, are known to be affected by plastics, with nearly every species of seabird consuming plastics. Most animal deaths are caused by entanglement or starvation due to ingested plastics blocking digestive tracts or reducing the urge to eat.

The primary source of plastic pollution in the oceans is plastic trash flowing from land, with major rivers acting as conveyor belts, picking up trash as they move downstream. Once caught in ocean currents, plastic waste can be transported globally and spread throughout the water column. Sunlight, wind, and waves further break down plastic waste into microplastics, which have been found in municipal drinking water systems, the air, and even human blood, lungs, and feces. The exact health impacts of microplastics are still being studied.

To combat plastic pollution, some governments have taken steps to limit or ban plastic bags, such as California's legislation to ban all plastic bags by 2026. International efforts are also underway, with the UN Environment Assembly (UNEA) approving a mandate to develop a global plastics treaty. The High Ambition Coalition, including the Netherlands, is calling for a strong and ambitious legally binding instrument to address plastic pollution. Events like World Environment Day in 2023 focused on solutions to plastic pollution, emphasizing the need to reduce plastic production to meet environmental goals.

The impact of microplastics on human health

Microplastics have been detected in human blood, saliva, liver, kidneys, and placenta. Scientists are investigating how they enter other organs and tissues from the lungs and gastrointestinal tract. The tiniest microplastics, known as nanoplastics, are the most concerning to researchers because they can enter cells and even cell nuclei.

Research has shown that microplastics can cause oxidative damage, DNA damage, and changes in gene activity, all of which are known risk factors for cancer. They have also been linked to reproductive issues. Furthermore, there are concerns that microplastics may carry antibiotic-resistant bacteria and other pathogens into our bodies.

As plastic waste continues to increase, the potential threats to human health from microplastics are also escalating. Preventative measures are required to limit our exposure to microplastics, such as reducing plastic waste and controlling the environmental discharge of mismanaged plastics.

Sea salt more vulnerable to plastic contamination

Sea salt is more vulnerable to plastic contamination than other types of salt. Sea salt is produced by the evaporation of seawater, and studies have found plastic in salt from the US, Europe, and China, adding to evidence that plastic pollution is pervasive in the environment. Microplastics have been found in 90% of table salt brands sampled worldwide, and the average adult consumes approximately 2,000 microplastics per year through salt.

The process of dehydrating seawater to make sea salt may be why it is more vulnerable to plastic contamination. As seawater is collected and evaporated, any plastic particles in the water can become concentrated in the salt. Plastic pollution in the oceans is a significant global issue, with an estimated 7,000-35,000 metric tonnes of marine plastic debris reported in a global oceanic survey. The most common type of plastic found in salt is polyethylene terephthalate, the material used to make plastic bottles.

The impact of consuming microplastics on human health is still unknown, but it could cause harm through physical and chemical pathways. Preventative measures are needed to limit human exposure to microplastics, such as controlling the environmental discharge of mismanaged plastics and reducing plastic waste.

In addition to sea salt, other edible salts derived from aquatic and terrestrial sources, such as lake salt and rock salt, can also be contaminated with plastic. However, sea salt had the highest level of plastic contamination among these salt types. Researchers found that traditionally harvested salts contained fewer microplastics than industrially harvested ones, suggesting that production processes may contribute to plastic contamination in salt.

Reducing plastic waste

Plastic pollution is a pressing issue, with microplastics being found in 90% of table salt brands sampled worldwide. The average adult unknowingly consumes about 2,000 microplastics per year through salt. This is a cause for concern, as the health impact of ingesting plastic is not yet fully understood. To reduce plastic waste and limit our exposure to microplastics, we must take preventative measures and make conscious choices in our daily lives. Here are some ways to reduce plastic waste:

Reduce, Reuse, and Recycle

The most effective way to reduce plastic waste is to minimize its creation. Opt for reusable alternatives to single-use plastic items. For example, carry a reusable water bottle, use cloth napkins, and bring your own tote bags when shopping. Reuse and repurpose plastic items whenever possible, and when buying new products, choose those made from recycled plastic materials.

Buy in Bulk and Minimize Packaging

Purchase bulk items with minimal packaging, such as buying staples like rice and pasta in bulk containers and storing them in jars at home. Look for products with non-plastic packaging, such as a glass jar of honey instead of a plastic bear container.

Properly Dispose of Plastic Bags and Wrappers

Plastic bags, wraps, and film are recyclable, but they cannot be placed in household recycling bins. Find specialized recycling locations for these items, often at local grocery or department stores.

Support Anti-Plastic Legislation

Encourage your local officials to introduce or support laws that discourage plastic bag use, similar to the initiatives in San Francisco and Chicago.

Educate and Advocate

Spread awareness about the issue of plastic pollution and the importance of reducing plastic waste. Share information on social media, with friends and family, and in your community. Advocate for change and support organizations working towards reducing plastic pollution.

By implementing these measures, we can collectively work towards reducing plastic waste and minimizing the presence of microplastics in our environment and food sources, such as salt.

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