Why is it not recommended to drink tap water?

Drinking water is a crucial element for human life and sustainable development. It is essential for health, hygiene, industry, and more. Yet, access to safe and healthy drinking water is a major challenge for many populations around the world.

For example, the quality of tap water can be compromised by various factors, such as microbiological, chemical contamination, or heavy metals. The aging of infrastructure is not to be overlooked. In this article, we explain why it is not advisable to drink tap water, as well as alternatives to ensure access to drinking water in your home.

Problems of tap water contamination and associated health risks

While tap water flows abundantly in households, its quality can sometimes be compromised, thus exposing consumers to health risks. Here are the main types of contaminants:

Chemical contaminants

The National Agency for Food, Environmental and Occupational Health Safety (ANSES) recently conducted a study on the presence of chemical contaminants in tap water in France.

The results are concerning:

• Pesticides and pesticide metabolites: 89 out of 157 have been detected at least once in raw water, and 77 in treated water.

• Explosive residues: 54 substances have been found.

• Solvents: 1,4-dioxane was detected in 8% of samples.

Naturally, long-term exposure to these contaminants can have harmful effects on the health of residents.

Effects of pesticides and their metabolites in tap water

Pesticides undertake quite a journey to found in tap water. Their presence can affect the nervous system, impairing cognitive functions and increasing the risk of Parkinson's disease. There are also consequences for the endocrine system, including hormonal disruptions, early puberty, and reproductive disorders.

The increased risk of certain cancers is not to be overlooked, particularly lymphoma and prostate cancer.

Consequences of the presence of explosive residues in tap water

The contamination of groundwater, from which tap water comes, by explosive residues is a danger to the nervous and reproductive systems. Consumption particularly exposes individuals to the following health problems:

• developmental disorders,

• tremors,

• seizures,

• decreased fertility,

• congenital malformations.

There is also an increased risk of developing liver cancer and bladder cancer.

Effects of the 1,4-dioxane solvent in the distribution network water

1,4-dioxane is an industrial solvent used in the manufacture of many products, such as cosmetics, detergents, and pesticides. Exposure to this chemical, even at low levels, can have harmful effects on health, including:

• Cancer: 1,4-dioxane is classified as a probable human carcinogen by the International Agency for Research on Cancer (IARC). It has been associated with an increased risk of liver, kidney, and lung cancer.

• Respiratory problems: Inhalation can irritate the respiratory tract and cause issues such as bronchitis and emphysema.

• Reproductive problems: 1,4-dioxane can harm fertility and fetal development.

• Nervous system damage: Exposure to this substance can cause headaches, dizziness, fatigue, and concentration problems.

Biological pollutants

While in general one can trust the quality of tap water in most regions of Europe, it is not always free from harmful microorganisms. The formation of biofilms, these colonies of microorganisms that accumulate on the walls of drinking water pipes, can promote the proliferation of bacteria and germs.

Thus, we distinguish two categories of germs present in drinking water: those that live in water and those that survive.

Germs living in tap water

Among the bacteria capable of living in tap water, we have:

• Legionella: These bacteria, responsible for Legionnaires' disease, proliferate in the biofilms of hot water pipes. Their multiplication is favored by temperatures between 25 and 55°C, making old, little-used pipes a conducive environment for their development.

• Pseudomonas: Present in moist environments, these bacteria can cause urinary, pulmonary, intestinal, and skin infections. They have become resistant to many antibiotics.

Germs surviving in tap water

Here are some bacteria and viruses capable of surviving in tap water (at least for a certain time):

• Coliform bacteria: The presence of Escherichia coli (E. coli) in drinking water indicates recent contamination by fecal matter. Consuming contaminated water can cause diarrhea.

• Enterococci: These bacteria, more resistant than coliforms, can survive for several weeks in water. They are responsible for urinary and cardiac infections, as well as abdominal wounds and abscesses.

• Salmonella, Enterobacter, cholera: These pathogenic bacteria can also survive in water and cause serious illnesses.

• Norovirus, rotavirus: These viruses, responsible for gastroenteritis, can be transmitted through drinking water.

• Hepatitis A and E: These viruses can also be contracted through the consumption of contaminated water.

Heavy metals

Contaminated drinking water with heavy metals can have devastating effects on human health. These metals, such as mercury, lead, cadmium, and arsenic, infiltrate water through industrial activity, agriculture, and waste disposal.

For example, lead, cadmium, and arsenic are known carcinogens. Other risks of heavy metals to public health include:

• Increased risk of heart attacks, strokes, and high blood pressure.

• Acute or chronic kidney failure.

• Increased risk of developing type 2 diabetes.

• Damage to the brain, spinal cord, and nervous system, which can lead to learning, memory, behavior, and motor problems.

• Bone weakening and increased risk of fractures.

• Reproductive issues, including decreased fertility and congenital malformations.

It should be noted that in a household, some individuals are more exposed to these risks than others. For example, the developing bodies of children are more sensitive to the toxic effects of heavy metals. Meanwhile, the kidneys and immune system of elderly individuals are often more fragile.

Limitations of water treatment and distribution systems

If thewater from the French network is generally controlled and meets drinking water standards, it can undergo alterations during its transport and storage in the pipes.

Here are some limitations of the water treatment systems in place:

• Old materials: Cast iron and cement pipes, often found in older networks, can release metals (lead, copper) into the water, weaken infrastructures, and increase the risk of leaks and microbial contamination.

• Recent materials: Organic materials such as PVC, polyethylene, and polypropylene, while easier to install and less prone to corrosion, can still influence water quality.

• Aging networks: Corrosion and the formation of biofilms on aging pipes can reduce the effectiveness of the disinfectant (chlorine) and promote microbial proliferation.

• Water stagnation: Stagnation zones in the network can lead to a degradation of organoleptic quality (taste, smell), a decrease in residual chlorine, and microbial growth.

• pH adjustment: Water is generally adjusted to a slightly alkaline pH (between 7 and 9) to limit scaling. However, variations in pH in the network, due to dissolved CO2, can affect the formation of biofilms.

• Residual organic matter: The organic matter not removed by treatments can serve as nutrients for microorganisms in the distribution network.

• Disinfection: The addition of disinfectants (chlorine, chloramine) helps reduce microbial risks, but can also react with organic matter and form potentially harmful disinfection by-products in the long term.

In France, strict regulations, developed by the Ministry of Health based on a European directive, ensure the sanitary quality of water, from the source to your tap. Throughout its treatment and distribution, water is subject to rigorous sampling and analysis by regional public health agencies, among others.

However, in the face of growing challenges related to pollution, aging infrastructure, and changes in water treatment, current standards may face limitations. For example, increasingly sophisticated water treatments can generate by-products whose long-term health effects are not yet fully known.

Public perception and distrust

While the majority of French people still usually consume tap water, a worrying trend is emerging: the consumption of tap water has been steadily declining since 1995.

According to a survey Conducted in France, the reasons for this disaffection for tap water are multiple, including an unpleasant taste and odor. The color is not to be overlooked, as there have been several reports of colored water distributed by the public drinking water supply network of Saint-André-de-Sangonis, near Montpellier.

According to some non-consumers of tap water, these quality issues are not limited to their city or region, but affect the entire country. This viewpoint can also be explained by certain scandals, such as major names in the water industry deliberately hiding the presence of chemical pollutants and bacteria in their products.

Moreover, distrust of tap water reinforces concerns about water pollution and fuels doubts about the transparency of information, even when it is provided based on real data. Some French people even think that it is wastewater that is treated before being redistributed to the tap.

In case of doubt about the quality of the water in your municipality, you can contact your regional health agency (ARS). Indeed, the quality of tap water can vary from one region to another and even from one neighborhood to another. It all depends on the quality of the water resource used, the treatment processes implemented, and the state of the distribution network.

Alternatives to tap water

Various alternatives exist to address the limitations of regulations regarding tap water quality controls, including bottled water and home filtration systems.

Bottled water

Bottled water is an alternative that may be necessary in certain situations, such as when traveling to areas where tap water is not safe to drink. Indeed, while water is safe to consume in most regions of France, its quality is often affected by agricultural contaminants in certain rural areas.

For daily consumption, tap water generally remains the most sensible choice. Although bottled water is often perceived as purer, it is not without problems. Microplastics have been detected in some brands, and incidents of non-compliance with standards have been reported.

Moreover, the production of bottled water leads to significant consumption of energy and resources, and generates billions of plastic bottles that pollute the environment. Additionally, its price can vary significantly, but it is generally much higher than that of tap water.

Home filtration systems

Home filters use different technologies to capture impurities present in tap water. For example, they are capable of:

• Reduce the content of impurities, such as chlorine and the eternal pollutants known as PFAS.

• Improve the taste and smell of tap water.

• Soften hard water.

• Preserve the important minerals present in the water.

Activated carbon filters are among the most common. Activated carbon is a porous material that absorbs organic impurities, such as chlorine, pesticides, and chemicals. In addition to using this effective technology, Weeplow filtration systems are available in various sizes to allow you to filter enough drinking water for your daily needs.

Take the right measures to drink tap water with confidence

Tap water in France is generally subject to strict controls and meets high drinking water standards. However, given the limitations of water treatment and distribution systems, it is important for consumers to remain vigilant and take certain measures to ensure its quality.

In this regard, remember to maintain your taps and pipes, as they can contaminate the water when they are in poor condition. Considering that bottled water has a significant environmental impact, you should prioritize filtered tap water if possible.

Browse our selection of gravity filtration systems to find the solution that will allow you to drink tap water with confidence.