Hormones in tap water

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Updated on: 02/12/2019

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For years Pharmaceutical residues in drinking water always a topic of conversation. Hormones in particular, which enter the water cycle through discarded chemicals, discarded tablets or natural excretions, have a major impact. Even the smallest amounts have the potential to trigger diseases in humans and animals. Nevertheless, the German Drinking Water Ordinance does not stipulate a limit value for drinking water, and filtering in sewage treatment plants has not yet taken place. In order to better understand the problem, it is also necessary to know an important distinction: There are not only real hormones in the water, but also hormone-active substances.

What do hormones do in the human body?

First of all, hormones are not negative, but vital. It is easiest to think of them as a kind of post in the body that transports information with instructions. They are so-called chemical messengers through which numerous bodily functions are regulated.

The natural hormones

Hormones are produced in the glandular cells of humans in certain organs such as the thyroid gland. From there they enter the bloodstream. The blood brings the hormones to the "reader" of the mail: Cells with special "docking points". There the message is then read out. Metaphorically speaking, hormones are used to switch certain switches in the body on and off and thus control organ functions. In this way, sexual function in particular, but also metabolism, breathing, blood pressure and the water and salt balance in the body are regulated.

The two sex hormones estrogen and testosterone are among the most well-known hormones. In addition, insulin, adrenalin and serotonin play an enormous role in human life.

Hormones serve as (post-)messengers of the body

Hormones are messengers

What effect do artificially supplied hormones have?

The best known form of artificially supplying the body with hormones is ovulation inhibitors. The "contraceptive pill" contains exactly those hormones that are present in the blood of a pregnant woman: estrogen and progesterone. The hormone level remains largely constant due to the artificial supply. Thus, the regulation by the superior control hormones is suppressed and ovulation is prevented. The pill thus protects against unwanted pregnancy.

Hormones that are not produced naturally in the body can also have an enormous effect on humans in other contexts. Their disastrous effect is known, among other things, from their misuse in professional sport through performance-enhancing doping. Masculinisation of female athletes and serious diseases are well-known consequences.

As a remedy, hormones are supplied in the context of endocrinology. The endocrinologist, a physician specialising in hormone therapy, administers hormones in order to supply diabetics with urgently needed insulin, for example.

But sometimes we also take hormones - or substances that promote the formation of hormones - without being ill. One example is the happiness hormone serotonin, whose production is promoted by chocolate. This creates the feeling that chocolate makes us happy.

Artificially supplied hormones

Artificially supplied hormones can have serious consequences.

Distinction between hormones and hormone-active substances

Anyone who wants to understand the effect of hormones in the environment and on humans must know the difference between the actual hormones and hormone-active substances, which either act like hormones themselves or influence the hormone balance. These non-genuine hormones are also referred to as endocrine disruptors or endocrine disrupting substances. "Endocrine disrupters are substances that either directly trigger effects in the inner secretory glands or influence glandular activities at the site of action. 1

Such an endocrine disrupter can, for example, induce the formation of proteins instead of a natural hormone, but can also impair the effect of other hormones. If an adolescent comes into contact with such a substance at the wrong time, it can lead to permanent functional disorders and defects of organs.

Pesticides may contain hormone-active substances

Pesticides containing endocrine disruptors can get into groundwater.

The big problem: not only drug residues, but also widespread plasticizers or hardeners used in the plastics industry, pesticides in tap water and cosmetics can be endocrine disrupting substances. As a result of industrial development over the last 150 years, we are surrounded by more and more such chemicals. Their exact effect on humans is still being researched, but known clinical pictures range from fertility disorders, behavioural changes and mental illness to suspected cancer-causing effects.

The unborn and small children are particularly at risk. For this reason, research on hormone-like compounds began as early as 1995 in the USA as one of five national priorities. Over 200 such substances are now known. 2
There are therefore good reasons for taking protective measures against contamination with substances with hormone-like effects. At the political level, there is planning within the EU framework. However, until these become concrete, only own measures can be taken. For a better understanding, it is important to know how the problematic substances get into our water and where they can be found everywhere.

How do hormones such as oestrogens get into our drinking water?

Oestrogens in particular are initially discharged into the wastewater through natural excretions and unused medication. The contraceptive pill plays a major role here. A study by the Federal Environment Agency estimates that the consumption of these hormones alone increased from 12,339.3 kg to 13,697 kg between 2002 and 2009. 3

Other medicines containing hormone-active substances get into the waste water, for example, by rinsing out bottles that you want to take to the glass container. In addition, there are the above-mentioned products of the chemical industry. Such substances are not filtered in sewage treatment plants, so they end up in rivers and surface water. In contrast to nitrates, endocrine disruptors are hardly broken down at all. In the end oestrogens find their way into drinking water.

Hormones in mineral water

However, such traces of hormone-active substances are not only found in tap water. Mineral water can also contain hormones.

Many consumers regularly reach for mineral water. However, this is precisely where there is also an oestrogenic burden. A study conducted by biologist Martin Wagner in the Aquatic Ecotoxicology Department of the Goethe University Frankfurt am Main on 20 mineral water brands led to revealing results. From the researchers' point of view, the mixture of different hormone-active substances found during their investigation proved to be particularly problematic. Samples of twelve mineral waters contained chemicals that activate the human oestrogen receptor. In an interview Martin Wagner explains that the samples found in the mineral waters had an effect equivalent to 18 mg of the natural hormone oestrogen dissolved in one litre of water. Water from PET bottles was particularly frequently contaminated. Part of the hormonal input probably came from the plastic packaging. Bisphenol A, a hormone-active substance with an estrogen-like effect, appears to be particularly problematic. 4 The exact consequences of this pollution for humans have not yet been researched. However, research into contaminated fish stocks provides a good insight into the effects of oestrogens.

Hormones also in mineral water. 12 of 20 mineral waters tested contained hormone-active substances

12 out of 20 mineral waters tested contained endocrine disrupting substances.

Hormones in water: What happens to fish and other creatures?

Within the framework of the aforementioned study, the researcher Martin Wagner stated: "Such an oestrogen load (as contained in one litre of mineral water) leads in the environment, for example, to the complete feminization of actually male fish. In fact, such hormone loads in surface waters are now not uncommon. The German Society for Nature Conservation (Bund Naturschutz, BUND) has intensively studied the hormone pollution in water and its consequences for fish and amphibians and has been sounding the alarm for years: not only natural but also artificial oestrogens such as alpha-ethynyl oestradiol, clofibric acid, phytoestrogens (active plant ingredients) and industrial chemicals are found in water. 5

Reduce hormones in tap water through water filter

The hormones in fish stocks eventually end up back on our plates.

How can hormones contained in water be filtered?

This can be remedied by water filtration. But which method is the right one?

Hormones can be effectively removed from tap water by activated carbon filters, reverse osmosis or distillation. Although reverse osmosis and distillation are highly efficient, they are expensive. During distillation, the container used must be thoroughly cleaned. Filtering with an ion exchanger is not sufficient to filter drug residues and hormones from the water.

High-quality activated carbon filters offer effective protection against hormone-active substances in drinking water. The activated carbon block filter adsorbs drug residues and hormones. Only the filter cartridge needs to be replaced every four months.

Adsorptive effect of activated carbon against hormones in tap water

The adsorptive effect of activated carbon can effectively combat hormone residues in drinking water.

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  • BUND: "Hormonally active substances in water" WWW: https://www.bund.net/fileadmin/user_upload_bund/publikationen/fluesse/fluesse_hormonaktive_substanzen_hintergrund.pdf (12.09.2001)
  • ibid. (1)
  • Federal Environment Agency: "Compilation of monitoring data on environmental concentrations of pharmaceuticals"
    WWW: https://www.umweltbundesamt.de/sites/default/files/medien/461/publikationen/4188.pdf (10/2011)
  • Ernaehrungs-umschau.de: "Oestrogenic load in mineral water"
    WWW: https://www.ernaehrungs-umschau.de/fileadmin/Ernaehrungs-Umschau/pdfs/pdf_2011/02_11/EU02_2011_083_085.qxd.pdf (02/2011)
  • Endocrine disruptors and pharmaceuticals - interrelationships, political assessment, strategy for action. A contribution to the 7th Environmental Medicine Conference - Berlin, 5-6 October 2007, Bund für Umwelt und Naturschutz Deutschland, Sebastian Schönauer, Dr. Hans Joachim Grommelt