Read the story here. Advertise at Before It's News here.
Profile image
By Alton Parrish (Reporter)
Contributor profile | More stories
Story Views
Last Hour:
Last 24 Hours:

New Method Estimates Risks of Hormone-Disrupting Substances in Drinking Water

% of readers think this story is Fact. Add your two cents.

Researchers at Karolinska Institutet have developed a new method that can make it easier for public authorities to assess the health risks of hormone-disrupting chemicals in the environment.

Credit: Nikthestoned / Wikimedia Commons

The method was used to evaluate the risk associated with exposure data from the population of Ronneby in Sweden where the drinking water had been contaminated with PFAS from fire-fighting foam. The study, which was published in Environmental Health Perspectives, shows that women are particularly at risk of decreased levels of thyroid hormone T3 (triiodothyronine) related to PFAS-contaminated drinking water.

PFAS (per- and polyfluoroalkyl substances) can be found in everything from ski wax to frying pans and fire-fighting foam. They are highly persistent and damaging to both human health and the environment. Amongst other effects, PFAS can cause weakened immune systems, lower birth weights and alter thyroid levels. At several places around the country, especially near fire-drill sites, high concentrations of PFAS have been found in the drinking water. There is therefore a pressing need to explore the health risks to which the local populations are exposed.

“It’s not enough to know that the levels exceed a limit value,” says lead author Antero Silva, doctoral student at the Institute of Environmental Medicine at Karolinska Institutet in Sweden. “We wanted to develop a method that describes how great the risk is while dealing with the uncertainty of the data.”

The problem with PFAS have been highlighted recently in the reality-based Hollywood film Dark Waters, which follows lawyer Robert Bilott (played by Mark Ruffalo) as he exposes how US industry has been covering up the risks of PFAS for decades. Legal proceedings are also underway in Sweden following a lawsuit against the municipal water company filed by the residents of one of the worst affected towns, Ronneby.

In this present study, the researchers have linked information on how PFAS influence the thyroid hormone T3, taking into account differences in sensitivity between individuals. Using exposure data from Ronneby, the researchers calculated how many people might be affected and estimated that around four per cent of the local women had blood PFAS levels high enough to cause a 10% drop in T3 levels.

“Using a large number of computer simulations we can describe the risk in terms of probability,” explains Antero Silva. “Our results show that it is mainly women who risk being affected and that those who have lived a long time in Ronneby are more likely to have reduced levels of the thyroid hormone T3.”

The thyroid hormone controls body metabolism, and an underactive thyroid (hypothyroidism) can lead to tiredness, concentration problems and depression. The hormone is also crucial to fetal development. In 2019, 472,000 people in Sweden were given drugs for low levels of thyroid hormone, 82 per cent of whom were women. The new study does not focus on the risk of disease, however, but on the likelihood of hormone levels being affected in a certain population group. It is therefore only possible to give the risk at population level, rather than identify which individuals are affected.

“There are many factors that determine whether or not you may get sick,” says Silva. “However, the body has an ability to compensate for environmental influence, but PFAS are a factor that can increases the risk of adverse effects. So, it is important for the health of those exposed to PFAS to be checked.”

The risks of chemicals in the environment are mainly assessed by comparing exposure with different limit values, which can give a false impression that there is a line that separates safe from dangerous. The researchers hope that the new method will be able to help public authorities analyse risks more carefully while paying closer attention to uncertainty and variation in the data.

The study was financed by the Swedish Research Council and the research council for sustainable development (Formas).


Contacts and sources:
Mattias Öberg,
Antero Vieira Silva PhD student
 Karolinska Institutet

Publication:A probabilistic approach to evaluate the risk of decreased total triiodothyronine hormone levels following chronic exposure to PFOS and PFHxS via contaminated drinking water, Antero Silva, Joakim Ringblom, Christian Lindh, Kristin Scott, Kristina Jakobsson, Mattias Öberg. Environmental Health Perspectives, online 8 July 2020, doi: 10.1289/EHP6654.



Before It’s News® is a community of individuals who report on what’s going on around them, from all around the world.

Anyone can join.
Anyone can contribute.
Anyone can become informed about their world.

"United We Stand" Click Here To Create Your Personal Citizen Journalist Account Today, Be Sure To Invite Your Friends.

Please Help Support BeforeitsNews by trying our Natural Health Products below!

Order by Phone at 888-809-8385 or online at

Order by Phone at 888-809-8385 or online at

Get our Free Ebook, "Suppressed Health Secrets"  with  Natural Cures THEY don't want you to know!

Humic & Fulvic Trace Minerals Complex - Nature's most important supplement! Vivid Dreams again!

Ultimate Clinical Potency Curcumin - Natural pain relief, reduce inflammation and so much more.

MitoCopper - Bioavailable Copper destroys pathogens and gives you more energy. (See Blood Video)
Oxy Powder - Natural Colon Cleanser!  Cleans out toxic buildup with oxygen! 
Organic Hemp Extract (CBD) - Full Spectrum high CBD (3300mg) hemp extract eases stiff joints, relieves stress and more!
Nascent Iodine - Promotes detoxification, mental focus and thyroid health.
Smart Meter Cover -  Reduces Smart Meter radiation by 96%!  (See Video)

Immusist Beverage Concentrate - Proprietary blend, formulated to reduce inflammation while hydrating and oxygenating the cells.

Report abuse


Your Comments
Question   Razz  Sad   Evil  Exclaim  Smile  Redface  Biggrin  Surprised  Eek   Confused   Cool  LOL   Mad   Twisted  Rolleyes   Wink  Idea  Arrow  Neutral  Cry   Mr. Green

Load more ...




Email this story
Email this story

If you really want to ban this commenter, please write down the reason:

If you really want to disable all recommended stories, click on OK button. After that, you will be redirect to your options page.