Microplastics and human health
27. July 2024
Microplastic removal saves water, energy, and costs
15. August 2024
Everyday helper: water bottle – microplastics in our lives
On the bike, running, playing football, or when travelling. It's hard to imagine sports and our everyday lives without plastic water bottles. Seen in almost every photo of athletes, not only at the Olympics and World Championships, but also at public races, in the gym or on the beach, they are our source for electrolytes and fluids.
They are a reusable product. Squeezable, unbreakable, and in most cases leak-proof and leak-tight. They are also convenient, easy to use, and recyclable, but often difficult to clean and in most cases in continuous use. So what do we do to our bodies when we drink from a plastic bottle? How much microplastic goes straight from the bottle into the body?
We are addressing this issue that is being pushed aside by many companies' marketing departments and where comprehensive and comparative data on microplastics is still scarce.
Microplastics are everywhere - nanoplastics, too
At the beginning of 2024, it was all over the world. You may have already read about it. Most of the media coverages, e.g. CNN or NIH reported on it. It's about these reports:
"Study: bottled water contains even more plastic particles than expected". And: "Bottled water contains 100 times more plastic nanoparticles than previously assumed".
Microplastics are already on everyone’s mind. Microplastics are solid and insoluble synthetic polymers (plastics) that are smaller than five millimetres. Microplastics have been entering our environment in an uncontrollable manner since the beginning of the mass production of plastics in the 1950s. As tiny masses of different types of plastic that are no longer visible to the naked eye, they are found heterogeneously distributed in water, soil and air. Microplastic detection has not yet been standardised across the board and the data sets have not yet been harmonised. However, while more and more publications on contamination are appearing, hardly any research team has worked across methods and devices, or the entire process from sampling to characterisation and foreign contamination has been excluded. Now comes the next piece of bad news, presented in the media with maximum uncertainty: nanoplastics are also an issue.
What are nanoplastics?
Nanoplastics are particles with a size of less than one micrometre. A micrometre is one millionth of a metre. A human hair is about 83 micrometres wide. Previous studies have looked at slightly larger microplastics, ranging from the visible 5 millimetres to one micrometre. According to the study, about 10 to 100 times more nanoplastics than microplastics were found in water bottles.
Nanoplastics from water bottles
An American research team announced new alarming figures at the beginning of 2024. According to the study, we ingest far more plastic with every sip of water than was previously known. The study, which used a new analytical method (single particle imaging using SRS microscopy), found that bottled water can contain up to 100 times more tiny plastic particles than previously thought.
The average litre of bottled water contains a quarter of a million nanoplastic fragments, according to a study by researchers from Columbia and Rutgers Universities in the USA.
The researchers analysed five samples from three common water bottle brands and found nanoplastic levels between 110,000 and 400,000 per litre, with the average being around 240,000. Much of the plastic appears to come from the bottle itself and the reverse osmosis membrane filter that keeps out other contaminants, said the study's lead author, Naixin Qian, a physical chemist at Columbia University in New York. She wouldn't name the three brands because the researchers need more samples before singling out one brand and because they want to study more brands. However, she said they were common brands purchased at the US supermarket Walmart.
We scrutinise the figures and classify them - microplastic analysis starts with sampling
We have already reported in many blog posts and also in our last article in Analytik NEWS that detection does not start with the analytical method, but much earlier – with sampling.
Accordingly, all results from scientific studies that do not already exclude potential errors and contamination during sampling with extensive comparative and zero measurements and analyse them in a scientifically correct manner by means of multiple measurements must be questioned.
We would also like to take this opportunity to point out once again that statements such as: "There are trillions of particles in the sea" are not meaningful, but rather misleading. Someone who writes such statements gets attention but misses the actual goal of finally arriving at a detection standard and defining guidelines and laws for more water without microplastics.
Maximum uncertainty due to unclear communication: What is behind the statement: "There are trillions of microplastic particles in the sea"?
- The figure is an estimate.
- It represents an opinion of a person or research group but is not a scientific consensus.
- The value says nothing about the actual contamination of the water with microplastics. It does not indicate a concentration.
For this, you would have to relate trillions to the amount of seawater. If you do this, a gigantic number (here: trillions) is quickly relativized. Because then we are talking about an average of one particle per litre.
The same applies to the statement: "A sewage treatment plant can remove 95% of the microplastic load in three purification stages".
This statement is also extremely misleading because it suggests that we have the issue under control. 95% of microplastics are removed sounds pretty good at first. So, everything seems to be wonderful. But....
- Hardly anyone asks what 95% means in kilograms.
- Hardly anyone asks what happens to the microplastics. They can't disappear into thin air.
- Hardly anyone issues the task to look for the supposedly removed microplastics in the sewage sludge and compare them with the values of the input water and the treated wastewater.
Are you wondering why this is the case? The answer is obvious: because it takes more than just one measurement to make a qualified statement. This requires extremely extensive data collection to obtain an adequate overall picture. This entails high upfront costs and then even more money when it comes to implementing measures that are used in accordance with the precautionary principle to reduce emissions into the environment.
The issue of microplastics is about transparency and clarity, not about media attention and marketing.
A comprehensive and comparative, standardised microplastic analysis could produce figures that no one wants to hear. It could provide figures that increase the pressure on decision-makers. But it could also provide answers to the burning question of whether and how dangerous microplastics and nanoplastics are to human health.
This is precisely why journalists asked questions and got the following answers:
The International Bottled Water Association explained in a statement: 'Currently, there are neither standardised [measurement] methods nor a scientific consensus on the potential health effects of nano- and microplastic particles. Media reports about these particles in drinking water therefore only serve to unnecessarily frighten consumers."
The American Chemistry Council, which represents plastics manufacturers, declined to comment.
The figures could perhaps show that the problem of microplastics in the environment is bigger than expected and that the effectiveness of our wastewater treatment plants is overestimated.
If you take a look at the water cycle and at which points and in which places high levels of contamination occur and discharges into the environment, take place, a clear picture emerges:
The wastewater that reaches sewage treatment plants is increasingly polluted, and increasingly contaminated with microplastics and other micropollutants.
The treatment and supply of drinking water in glass bottles, PET bottles, and as tap water from the mains, is the final link in a very long chain. To protect drinking water, we must act sensibly at the beginning of the process – in industries and in sewage treatment plants.
The problem of polluting our water with microplastics, nanoplastics, nanomaterials, micropollutants, heavy metals, and all the other various chemicals starts at the beginning of the process chain. In our industries, in production, processing, manufacturing of products, and even in recycling.
The positive effects on water quality that could be achieved if process monitoring along with innovative technologies for removing microplastics and the circular economy went hand in hand at an early stage have been demonstrated by our work for many years. The marketing and sales departments of other providers of so-called solutions are now also jumping on this bandwagon. Nevertheless, the solution does not lie in installing the 17th filter in our households (most of them made of plastics) or buying a new washing machine with an innovative microplastic filter (see also our blog posts on this).
The solutions are obvious and cost less than expected
We (humans) can adjust our consumer behaviour and act more sustainably during the use phase of products. But there is little we can do about it if the markets are flooded with more and more unsustainable products, or if companies' marketing encourages us to make pointless purchases and consume more and more. Or when we are made to feel incredibly guilty if we don't implement a measure. It's not about having 50 more sustainably produced T-shirts in your wardrobe, which may be worn just as little as the 5 non-sustainably produced T-shirts. Rather, it's about questioning whether you really need things and products.
If we maximise the turnover frequencies between purchase, use, and disposal, we are actively protecting the environment. Because quite honestly, it's not that difficult to throw a cigarette in the bin instead of flicking it on the street or throwing it down the drain. Or taking rubbish back from the beach instead of leaving it lying around. These are small changes with maximum immediate impact. And it doesn't hurt at all!
And now back to our water bottle test
As we are passionate athletes ourselves and have been working with more and more people since 2024 as part of our "we [...] for water" campaign to communicate more about global microplastic pollution and collect data for the Global Map of Microplastics, we have focused on the sports drinking bottle in an “everyday” research project.
We analysed the release of microplastics from two standard bike bottles, the kind you can buy everywhere or are often given out.
No water bottle was provided free of charge. The study was also not co-financed by any well-known companies (suppliers of water bottles). It is a 100% independent and non-influenced study that was financed exclusively by our own funds.
For our study, we exposed the bottles to a temperature of 40°C. Incidentally, this is the recommended temperature for cleaning sports bottles. You should avoid exposing the sports bottles to aggressive chemicals over a longer period of time, e.g. in dishwashers. This treatment step massively attacks the surface of the soft plastic and thus ensures a shorter service life and faster ageing.
Household tip
Wash your sports bottles with tap water, use a soft brush (preferably without plastic bristles) and avoid aggressive chemicals. Citric acid fulfils its purpose wonderfully here.
How we performed the analysis?
- We heated a defined amount of water in the bottles to 40°C.
- Samples were taken and analysed at the start of the experiment (at 0 min), as well as after 60 min and 120 min.
- A total of 60 measurements and 24 blank measurements (to exclude possible foreign contamination) were carried out.
- Microplastics were detected using innovative fluorescent markers and fluorescence microscopy.
- The latest findings in the field of error source avoidance, standardisation and harmonisation were used directly.
What was the result?
Only two of the microplastic measurements were higher than the blank measurements. Accordingly, no reproducible migration of microplastics from the drinking bottle into the drinking water could be observed from the selected bottles.
That's good news for now! At this point, a note on our own behalf: If you find bike bottles in your product range in which nanomaterials (such as inorganic titanium or zinc compounds) have been processed in addition to plastics, it is possible that nanoparticles from these compounds may find their way into the drinking water. And everyone has to decide for themselves whether they want this. More information on this topic can be found on the BUND website.
