We cyclists carry them with us on almost every ride: our drinking bottles. Even those who swear by drinks made from glass bottles in everyday life and generally avoid plastics as a waste product usually have a plastic drinking bottle stuck in the bottle cage. Other materials are hardly ever used. Glass is not only heavy, but also not entirely harmless. In the event of a fall, the bottle can shatter. Glass is also not crushable. The same applies to bottles made of metal, which are often found in mountain sports. Stainless steel is heavy and the “light” aluminum is hazardous to health. So there seems to be no getting around plastic.
What are the most commonly used plastics?
Plastics – colloquially known as plastics – can have very different properties. The list of plastics is long. There are several hundred different plastics. They are divided into different types. One way of classification is into the following three groups. Hard plastics with crystalline structure are called thermosets. Soft and elastic plastics are called elastomers. Thermoplastics include plastics that can be (re)formed at higher temperatures.
The most commonly used plastic is PE (polyethylene), because PE is very durable and changeable. PE is often used for bicycle bottles because it is malleable at normal ambient temperatures even without plasticizers. Close behind in frequency of use is PP (polypropylene). The heat resistance is higher with PP. In third place in frequency of use is PVC (polyvinyl chloride). It is one of the best known plastics and one of the most harmful to the environment due to its high chlorine content. It can also be dangerous for people, especially children, and is suspected of promoting cancer. PET (polyethylene terephthalate) is mostly used for plastic beverage bottles sold in grocery stores. It has high rigidity and abrasion resistance, is relatively hard and resistant to dilute acids, oils, fats and alcohol. However, PET does not tolerate high temperatures or (boiling) hot drinks.
What’s the problem with plastic?
Plastic does not usually degrade in the environment. Our oceans and nature in general are full of plastic waste. But also our health is endangered. In general, plastic has a tendency to quickly grow mold. Bacteria love it moist and find a breeding ground on plastic. A rough surface, reinforced by cracks and scratches, is particularly susceptible. Plastic mouthpieces increase the proliferation of harmful organisms. Viruses survive there for longer periods of time. And this alone is all true when using still water alone. With sugar in the liquid, fungi and bacteria can sometimes multiply explosively. Also harmful are the additives contained in plastic, such as UV stabilizers, plasticizers or flame retardants. One common additive is bisphenol A (BPA). It is processed almost everywhere in plastic. Humans can hardly escape it and BPA is found in our body fluids and tissues such as blood and urine, but also in amniotic fluid and uterine tissue. Studies show the highest levels of exposure in children. BPA is similar to the hormone estrogen and is blamed for hormone imbalances with infertility in men. If the abbreviation PC is found on plastics, BPA may be present. Although according to many manufacturers no BPA is used (anymore) for PET bottles, estrogen-like impurities are found again and again in mineral water from PET bottles. But plastic is also spreading in our bodies. So-called microplastics with a diameter of less than 5 millimeters get into many parts of our body. How it interacts with our bodies is not yet entirely clear. Research into this is still in its infancy.
Study: Researchers discover hundreds of released substances in plastic bottles
Plastic bottles are generally not completely scratch-resistant, and in the event of the slightest damage – which is unavoidable during use and also occurs during rinsing – the material sometimes releases contained additives into the liquids. Where the musty smell of plastic bottles comes from has been investigated by a team of researchers at the University of Copenhagen using tap water . Although reusable plastic sports bottles are used extensively around the world, little is known about the release of chemicals from the bottles into drinking water. The researchers wanted to know what chemical substances were released into drinking water that had been in the bottles for 24 hours. New and used bottles were previously cleaned in the dishwasher for this purpose. In connection with rinsing in the dishwasher, thousands of released substances could already be detected in the rinse water. But even after the rinse cycle, more than 400 plastic-related compounds were released into the water. The study also shows how important it is to consider special cleaning steps for plastic bottles. Dishwasher-related compounds were found to attach more strongly to plastic than to glass, some of which were difficult to remove even with additional rinsing with water. In addition, dishwashing increased the release of plasticizers and other substances into drinking water. Therefore, the highest toxic hazard results for used plastic bottles refilled directly after dishwashing without further rinsing. However, undesirable substance compounds were also found in the new bottles, which are continuously released, even after rinsing. The study also raises the question of whether plastic bottles are suitable for reuse, especially if they are labeled as biodegradable plastic, since the production of biodegradable plastic bottles does not necessarily mean that the bottles are made of naturally occurring compounds. Instead, there is a presumption that the plasticizers pass more easily into drinking water when the biodegradable plastic bottles slowly decompose during use.
The alternative: KEEGO
The young start-up KEEGO struck a new path: Drinking bottles with titanium for unadulterated taste and plastic-free drinking pleasure. Although the KEEGO bottles cannot (yet) completely do without plastic, KEEGO keeps the drinking water or liquid inside the bottle free of plastic. Thanks to a titanium coating, no particles from the outer plastic shell reach the filled liquid. Titanium does not mold, does not contain microplastics or plasticizers. The mouthpiece on the lid is made of silicone. KEEGO is based in Austria and produces in Germany. The drinking bottles are constantly being further developed. Were the bottles a few years ago in the first version still somewhat difficult to squeeze, in the current 4th generation is no longer noticeable difference to ordinary plastic bottles. KEEGO bottles are also super light and durable. After use, KEEGO bottles can be fully recycled.
KEEGO has convinced me. For all those who also want to convince themselves of KEEGO and the unadulterated taste, there is a 15 percent discount with the discount code WETTERFEE15 when buying at KEEGO.SHOP.
The advantages of KEEGO drinking bottles at a glance:
UNFAMILIZED TASTE: Pure titanium ensures that your drink remains unadulterated and refreshing. Plastic taste is a thing of the past with KEEGO.
CLEAN AND HEALTHY: KEEGO prevents liquids from being contaminated by microplastics. Experience antibacterial drinking pleasure without plasticizers, BPA, BPS or mold.
SQUEEZABLE: KEEGO drinking bottles are easily squeezable with elastic titanium for effortless, quick, one-handed drinking.
DURABLE AND SUSTAINABLE: Titanium is extremely durable and easy to clean. As a result, KEEGO will last an average of 5x longer in use than comparable squeezable water bottles.
LIGHTWEIGHT: Your gear stays light and compact. At only 86g, the KEEGO combines the lightness of a sports bottle with the durability of a metal bottle.
Literature on the subject:
 Tisler S, Christensen JH. Non-target screening for the identification of migrating compounds from reusable plastic bottles into drinking water. J Hazard Mater. 2022 May 5;429:128331. doi: 10.1016/j.jhazmat.2022.128331. Epub 2022 Jan 22. PMID: 35091188.
 Kerstin Becker et al., Kinder-Umwelt-Survey (KUS) 2003/06, Human-Biomonitoring-Untersuchungen auf
Phthalat- und Phenanthrenmetabolite sowie Bisphenol A, Im Auftrag des Bundesministeriums für Umwelt, Naturschutz und Reaktorsicherheit (BMU) und des Deutschen Zentrums für Luft- und Raumfahrt e.V., Projektträger des Bundesministeriums für Bildung und Forschung (BMBF), Berlin, 2009, ISSN 1862-4340, https://www.umweltbundesamt.de/sites/default/files/medien/376/publikationen/umwelt_und_gesundheit_04_2009_webfassung_korrigiert_2009_09_10_1.pdf
 Konieczna A, Rutkowska A, Rachoń D. Health risk of exposure to Bisphenol A (BPA). Rocz Panstw Zakl Hig. 2015;66(1):5-11. PMID: 25813067.
 Ma Y, Liu H, Wu J, Yuan L, Wang Y, Du X, Wang R, Marwa PW, Petlulu P, Chen X, Zhang H. The adverse health effects of bisphenol A and related toxicity mechanisms. Environ Res. 2019 Sep;176:108575. doi: 10.1016/j.envres.2019.108575. Epub 2019 Jul 3. PMID: 31299621.
 Rhodes CJ. Plastic pollution and potential solutions. Sci Prog. 2018 Sep 1;101(3):207-260. doi: 10.3184/003685018X15294876706211. Epub 2018 Jul 19. PMID: 30025551.