Water Quality
How Good Is Our Tap Water?
Is tap water really safe to drink? We examine water quality in Switzerland, potential contaminants, and whether water filters are worth it.
Water Quality
Is tap water really safe to drink? We examine water quality in Switzerland, potential contaminants, and whether water filters are worth it.
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Have you ever wondered where the fresh water comes from that flows from your tap when you turn it on?
In a world where we constantly read about how much trash ends up in the environment and industries readily dump their wastewater into the nearest river, you have to ask yourself whether we're doing ourselves a favor.
Because the more unwanted substances that enter rivers and groundwater, the more water treatment plants have to filter out in order to make fresh water drinkable for us. Let's find out ;-)
What's in the Water?
Switzerland's drinking water protection regulations already include a long list of contaminants such as heavy metals or nitrate that are banned from drinking water above defined limit values. You can find a detailed list of which substances are filtered out in water treatment plants in Swiss water legislation.
However, new substances keep appearing in drinking water and in waterways that could potentially be harmful to health. Currently, microplastics, pharmaceuticals, and other hormone-active substances are the main topics of discussion. These substances have not yet been fully incorporated into drinking water protection regulations, but they are now on a monitoring list according to EU drinking water directives.
The Swiss Federal Office for the Environment (FOEN) writes about pharmaceuticals: «Raw water for drinking water treatment can be contaminated in low concentrations with active pharmaceutical ingredients.»
This is why investigations are already underway at Swiss and European levels to determine what measures could prevent these concentrations from increasing further or even minimize them.
Regarding hormones in waterways, the FOEN writes: «In recent investigations, a variety of steroid hormones from medications have been detected in wastewater treatment plant effluents and waterways.»
The introduction of regular measurements of these critical substances doesn't happen overnight, unfortunately. The transition requires new, additional filter systems in water treatment plants and above all it must be clarified who will finance them.
For pesticides, a limit value has already been defined. This means that pesticides are only allowed in drinking water up to this limit value.
Sidebar: But Where Do These Limit Values Actually Come From?
They are formulated in the EU drinking water directive and adopted by the Federal Office of Public Health (FOPH) in Swiss drinking water protection regulations. Regular reviews and inspections are designed to provide optimal protection for consumers.
Exceeding these limit values should not pose an immediate danger, as they are set such that consumption only becomes problematic over a longer period of time.
Let's state the good news clearly: Drinking water quality in Switzerland is very high and subject to strict controls. The treated water meets strict quality standards.
A Small Drinking Water Basics Course
Now here's the catch: Water treatment plants only monitor drinking water up to the house connection – contamination from the house connection to the tap is your own responsibility.
Here's what you should pay attention to:
→ Tap water is not sterile.
This means it always contains small amounts of bacteria. To prevent the growth of Legionella in pipes, the following should be noted: Water should be either really cold or really hot. This is because Legionella multiplies most at health-hazardous concentrations in a range between 25 °C and 55 °C.
Stagnant water that has sat in pipes for longer than four hours should not be used for drinking or food preparation – this applies, as always, especially to vulnerable populations such as pregnant women, babies, elderly or sick people.
→ The Lead and Metal Question
The use of lead pipes has been banned since 2023, and by 2026 pipes in all buildings must be replaced or decommissioned, since lead can be neurotoxic in babies and also has a generally toxic effect.
Copper pipes are also frequently used in buildings. In theory, they can release copper ions into the water. In practice, however, a protective patina usually forms on the surface, so copper ions rarely end up highly concentrated in tap water.
A tip: You can easily order drinking water test kits today (for example via Amazon) that can be sent to laboratories. A wide variety of metals are measured here. This way you can also take extra precautions yourself if the topic concerns you.
If measurements do show increases, it's most likely due to your own building's pipes, which are either very old, made of corroding material, or water sits in them for too long.
Is a Water Filter Worth It?
This raises the question of water filters. Of course, context matters here. We don't usually tap pure mountain water directly at the source.
As an alternative to tap water, people typically turn to bottled mineral water.
However, bottled mineral water has two major drawbacks: It's significantly more expensive than tap water. Moreover, contamination with microplastics, especially with plastic bottles, is a major issue, though glass bottles don't fare much better either.
Therefore, you could filter the water at home – to be on the safe side. There are various filter systems:
Activated charcoal is able to bind contaminants in water. In reverse osmosis, contaminants are filtered out through pressure from a system of filters and membranes.
Two studies showed:
«According to the results, activated charcoal and reverse osmosis were 100% efficient at removing pesticides» and «Granulated activated charcoal was highly efficient at removing all target chemicals.»
This means: Activated charcoal and reverse osmosis filter systems could most effectively remove unwanted substances such as pesticides, hormone-active substances, and pharmaceuticals. Ion exchange procedures, on the other hand, filtered out fewer substances from the water.
If you also have very hard water in your region or city, meaning water with very high levels of magnesium and calcium, a water filter might be worth it. Because even though high mineral content is not harmful to health – quite the opposite, calcium and magnesium have protective health effects! – it is very unpopular especially among tea and coffee lovers.
Important to keep in mind with all filters: All filters or devices must be regularly replaced or cleaned according to the instructions. Otherwise, they can become a source of further contamination!
Let's Sum Up
If you decide to use tap water, you not only get a significant price advantage, but you also avoid the hassle of hauling water crates around.
Water from the tap is and remains a very strictly controlled food product, but if you want to be extra safe, you can install a water filter at home. Based on current data, filters with activated charcoal and reverse osmosis are best suited.
It remains unclear how water treatment plants will handle the increase in environmental toxins in waterways and groundwater in the future, and whether current limit values will provide adequate protection for our health in the long term.
In fact, most people nowadays have no other choice: Through drinking water we inevitably come into contact with unwanted substances. The only question is in what quantity and with what health relevance. Sobering!
Sources
Danopoulos, E., Twiddy, M., & Rotchell, J. M. (2020). Microplastic contamination of drinking water: A systematic review. PloS one, 15(7), e0236838. doi.org/10.1371/journal.pone.0236838
Schreiber, F., Donato, F. F., Kemmerich, M., Zanella, R., Camargo, E. R., & de Avila, L. A. (2024). Efficiency of home water filters on pesticide removal from drinking water. Environmental Pollution, 341, 122936. doi.org/10.1016/j.envpol.2023.122936
Snyder, S. A., Adham, S., Redding, A. M., Cannon, F. S., DeCarolis, J., Oppenheimer, J., ... & Yoon, Y. (2007). Role of membranes and activated carbon in the removal of endocrine disruptors and pharmaceuticals. Desalination, 202(1–3), 156–181. doi.org/10.1016/j.desal.2005.12.052
