Never again afraid of PFAS

January 17, 2024 by Theo Richel.

In 1984 I made a report for a Dutch leftwing tv-station about the contamination of breast milk with so-called PCBs and dioxins, dangerous substances that seemed to disrupt the development of the infants. No longer than six weeks of breastfeeding advised a chemist on the broadcast! Mothers tore their babies off their breasts in a panic, the Telegraaf headlined: Infant care overrun by breast milk panic! Everyone knew: another poison scandal!

‘Our’ scandal was, of course, just one in a long line. In those years ‘poison dumps’ were discovered everywhere, homes were evacuated, products were withdrawn from the market (dioxin chickens! Seveso!), sites were closed off and the media constantly reported on exotic-sounding chemicals that would ruin our food or drinking water. ‘Can you rule out the possibility that people will get cancer from this?’ as a radio reporter, did I ask a professor of toxicology? He said, ‘No, I can’t rule that out’. Of course he couldn’t rule that out, but by adding a few seconds of silence behind that statement, the whole thing took on a threatening character and the listeners understood that something very creepy was going on here! Scaremongering, therefore, factless but effective. I don’t have hard numbers, but I think the majority of the Dutch are convinced that we are all being poisoned with industrially produced cancer-causing chemicals. This is chemophobia, needless fear of chemical substances and I have enthusiastically encouraged it over the years. I have now come to very different insights, so here is a kind of dummy guide to better understand when the media scare you about hazardous, often carcinogenic, substances. How do they get there? When is a substance carcinogenic and how afraid should you be? What happens if you ingest a carcinogenic substance? And are we perhaps taking science TOO seriously?

This story would have been much shorter if we all remembered this 500 year old lesson from the Swiss physician Philippus Aureolus Theophrastus Bombastus von Hohenheim also known as Paracelsus: Dosis Sola Facit Venenum. That means: it is the amount that determines whether a substance is toxic. You need a few grams of table salt per day to stay healthy, but 10 times as much is deadly. You need air with 20% oxygen, 100% oxygen destroys your lungs, without water you die but drinking 3-4 liters in a few hours is lethal too. None of this is news and this wisdom is universal, and in 99 out of 100 poison scandals you can shrug your shoulders just because it involves a tiny amount of a certain substance, it is the dose that determines the danger. But instead of shrugging there is panic, because you are intimidated by a scientific haunted house full of rattling skeletons and shaking gravestones. Cancer! Cancer! Cancer!

The bogeyman du jour is now PFAS, a collective name for thousands of per- & polyfluoroalkyl substances . They repel both water and grease and thus ensure the smooth bottom of pizza boxes, non-stick pans, waterproof clothing and much more. They are called Forever Chemicals because supposedly they never break down (that’s not true, but it does take years) and they are found in small quantities in humans, animals and the environment. They are suspected of causing all sorts of health problems. In the Netherlands advice has already been given not to eat too much self-caught fish (from the Western Scheldt). The organization Toxicowatch worries about PFAS in face masks and the Dutch government tries to limit the use of PFAS. Even a newspaper that is known for its critical attitude towards green scares (De Andere Krant), ran the headline: ‘Toxic substances are flooding our living environment’. And in a subsequent issue a concerned immunologist Dr Carla Peeters said: ‘ We have made 100,000 chemicals in the last fifty years that did not exist before. We don’t know what the long-term effects will be.’

I am willing to believe that chemists have developed 100,000 chemical substances in the past half century, but it seems difficult to rule out the possibility that nature beat them to it. How to know on a planet with 177 million different more or less identified chemicals [1]; I understand that chemists are still regularly surprised. Nature is a chemical factory. Substances are added 24/7/365 and undoubtedly disappear again. People also contribute to this, through industry and through the kitchen. A cooked potato is a chemical product and its composition varies, depending on whether it is an Eigenheimer or a Bintje, fried in oil or butter, on induction or on gas, on a low burner or full fire. We cook beans to make them less toxic, we try to neutralize the oxalic acid in spinach with eggs, or we make the meat more toxic because a little bit burnt is quite tasty. Chemistry! A person ingests 200,000 different chemicals every day, of which we know nothing.


Fear of poison is of all times. Kings used to employ “poison tasters” who took the first bite, but today we fear not so much that we won’t wake up the next day, but that we will get cancer half a century later. And this is not about a whole plate of food, but about a few milligrams of, for example, a pesticide or another substance that does not ‘belong’. Science now has the role of poison taster and it must meet high standards: if you can prove that Substance X causes cancer in only 1 in a million people, then measures must be taken.

1 in a million people, that sounds very safe, but to discover something like that you have to set up a study with two million people. Half get Substance X and the other half you keep ‘clean’ and that during several for decades – cancer is a slow disease – and then count tumors.  That is of course impossible (and also unethical because you are not allowed to administer potentially dangerous substances to people) and nobody wants to wait that long.

Science therefore opts for laboratory animals, usually rats or mice, but an experiment with two million rats will probably be considered an environmental problem by the authorities. The Mega Mouse study in the 1950s once counted 200,000 mice, it has never been repeated.

So they take 1000 rats, or even less, but that has the disadvantage that you can only calculate a chance of 1 in 1000, not 1 in a million.

This is ‘solved’, more or less, by giving the animals a dose that is a thousand times higher than what an average consumer would ingest.

This is a caricature of things but essentially correct. In such research, the test animals are given megadoses that are thousands of times higher than that pesticide residue in that salad on your plate. It is therefore not surprising that in such research half of all tens of thousands (?) investigated chemicals, whether natural or artificial, do cause cancer in laboratory animals. ‘If you give enough, you can cause cancer with any substance,’ says chemist Jaap Hanekamp of University College Roosevelt in Middelburg, the Netherlands. Much of the fuss about carcinogens is based on this type of animal experiments, rarely on human research. After all, that is much more complex.

This approach assumes that a large amount of a substance will have more or less the same effect as a smaller amount. The effect is said to be ‘linear’ and only a ZERO dose has no effect. In everyday life, outside of science, everyone has known for a long time that this is not true, but science doesn’t seem that far yet. I will come back to this under the heading Hormesis .

And what to do if it turns out that the test animals get cancer in their tails or their forestomach from such a mega dose of Substance X? People don’t have those. Rats and mice make their own Vitamin C, humans don’t, what does that mean? And what should you do if it turns out that animal species react differently?

‘Dioxin is a good example of this,’ says Hanekamp. ‘ In the 1980s they called it a super poison , but now people joke that dioxin is the most toxic substance for hamsters . They underwent the first tests and they fell over ‘immediately’. Then they tested it on rats and you could stuff them with dioxin and they wouldn’t give a damn.’

Humans are surprisingly insensitive to dioxin. The substance is carcinogenic only in super high doses, and even then…. In 2004, then-Ukrainian President Yuschenko was poisoned with 5 million times the permitted amount of TCDD, supposedly the most dangerous type of dioxin. He suffered from chloracne, a nasty skin disease, for many years, but recovered. In 2021 he was still alive. Years ago it was also discovered that humans can also produce dioxins, albeit at a very low level.

According to the German specialist Prof. Mueller from Braunschweig, the dioxin standard is a thousand times too strict [2]. In small doses, it seems, dioxin can even reduce the risk of cancer . Incidentally, dioxins have more or less disappeared from the scene because nature is an extensive source of these and similar substances.

These animal experiments have also been carried out with some PFAS substances – there are thousands of them. Dr Hanekamp: ‘I have worked through the fundamental literature for a number of PFAS substances for the ‘norm’, so I know how the toxicology was done. Then you do indeed see that rats and mice with high exposures are being investigated and then I think, well, what can I do with that, it is much too high, often a million times higher than what we have in terms of exposure and then the question is of course: can I do something with that? It’s not very exciting yet’.

Many people opt for organic unsprayed fruit and vegetables in the firm expectation that they will consume fewer pesticides. They are fooling themselves. A head of lettuce does not have the ambition to end up on a consumer’s plate as pure as possible, it just wants to make small heads of lettuce and see them grow. That doesn’t happen automatically because insects, mites, fungi and other scum lurk and to ward them off, the head of lettuce can only make chemicals, natural pesticides. In the case of lettuce, it is the carcinogenic caffeic acid. Your entire organic greengrocer’s shop is full of similar natural carcinogens, totally comparable to their industrial competitors. Piperine in pepper, d-limonene in oranges, catechol in coffee, hydrazine in mushrooms, flame retardants in sea vegetables and much more. Hanekamp: ‘PFAS really is a wimp compared to those substances, especially when you consider that more than 10,000 different halogenated hydrocarbons of natural origin have already been found in the world, almost all of them highly reactive substances!’

The use of commercial spray products is very limited by law, so you only ingest a few milligrams of those products; of the equally dangerous natural pesticides 10,000 times as much. Grams! [3] None of this is a reason to radically change your diet, but rather a warning not to expect everything from science.


But dozens of human studies have now also been carried out, not with megadoses, but on the basis of the – minute – amounts of PFAS that people ingest through the environment. According to such studies, PFAS is associated with: high blood pressure during pregnancy (eclampsia), impaired liver function, elevated cholesterol, reduced immune function, lower birth weight and cancer.

I used to find this very impressive and run straight to my editorial office to report in an excited tone that things were not going well! ‘Science says…an association.. cancer could… could’ but now I’m much more careful.

In science, one egg is no egg, two eggs is half an egg, three eggs is an Easter egg. To get the results of a study widely accepted, you have to replicate it, do the same test in a different place, and get the same or similar results. That is a big problem nowadays, there is a replication crisis, a large part of the research seems like a kind of one-hit wonders. The American Council on Science & Health (ACSH), a kind of Green Court, looked at 47 studies on PFAS and cancer . In 38 of these, no connection was found, in 9 cases there was, but then there were usually also studies with a contradicting result. By no means unequivocal.

But an ‘association’ in itself means little. It used to be joked that the birth rate in the Netherlands was declining and at the same time there were fewer storks, that connection couldn’t be a coincidence, could it?

It is extremely difficult to really determine whether a particular ailment is caused by Substance X or whether something else is going on. More lung diseases occur along a highway, is it due to air pollution from traffic or due to the fact that poorer people often live in such a place and smoke more? It’s extremely complicated to unravel things like that. And it becomes even more difficult as you want to know something about the long-term effects of very small amounts of a substance. There are an astounding number of factors that can make an investigation unreliable, ranging from misconfiguration or incompetence to blatant fraud. Do people really have cancer? Has the dose been measured correctly? Isn’t the number of people studied much too small? Perhaps the publicity distorts our view of the matter? Do researchers have commercial or ideological interests in the result? It all happens on such a scale that the Greek American professor John Ioannidis published an article in 2005 entitled ‘Why most published research findings are false’ [5]. In essence, most of the scientific research of recent decades can go in the trash. The article hit like a bombshell, and Ioannidis is taken very seriously, but it will be some time before the policy is changed.

That is the background against which you have to judge alarming reports about PFAS and all those other substances. The ACSH is therefore not impressed by the dangers of PFAS: ‘It is very rare to have a chemical with so much human data that shows so little adverse effect. Multiple studies did not find an association between PFOA and immune effects, developmental effects, or cancer. Yes, there are some positive studies, but a fair and accurate assessment involves examining the totality of the data and reaching a conclusion based on all studies’.

Contrast that with the advice from the Dutch (regional) government about the increased PFAS concentrations in fish. They think it is ‘important to eat as little as possible of products from the Western Scheldt’ and even detail this:

‘A portion of self-caught flounder from the Western Scheldt can be eaten twice a year. For sea bass this is 1 to 6 times and for smelt 2 to 15 times. A portion of whiting can be eaten 4 to 19 times a year and a portion of shrimp 5 to 6 times. For oysters and mussels from the Western Scheldt, this is a maximum of 7 times a year to 2 times a week.’ [6]

Hanekamp: ‘That is not based on anything! Is not based on a security analysis of any stature. We just don’t know enough about it, but at least we know that these substances are not very reactive. Also not based on acute or chronic insecurity. What irritates me the most is the very narrow focus on those kinds of substances, while nature is bursting with so-called halogenated substances with a much stronger reactive nature’.

The only effect of such a recommendation is fear on the part of the citizen and satisfaction at the provincial house that people are taking good care of the citizen after all.


The Dutch advice is an example of scientism, the overconfidence in the absolute and unassailable wisdom of SCIENCE!. Hanekamp calls it the ‘curse of our times’ [7].

As a beginning journalist I was annoyed by the modesty of the scientists I interviewed about their own work: ‘We actually know very little. I can’t say anything yet, come back later and maybe we’ll know more.’ It was humility and caution and I wanted clear, preferably alarmist statements.

This has changed dramatically under pressure from the media, politicians and the universities themselves. Scientists no longer limit themselves to their own small field but tell you what is wrong with the entire planet, now and in the future, including years. Problems and solutions, these scientists/activists know everything, because there is CONSENSUS! The Science Is Settled! And from society people are fully confirmed in that supreme wisdom: ‘We believe The Science!’ it sounds ignoring the fact that science advances mainly through criticism and doubt, not through submission to authority.

There are such consensuses in the field of cholesterol, radioactivity, toxicology (LNT), climate and probably many more. In each case a group of scientists freezes a certain scientific point of view at a point in time. From then on they agree to speak with one voice and tell the same story! No more confusion. Good for scientific prestige and also very pleasant for the government, which provides money for scientific institutes where that established truth is further developed. Also very nice for the media for whom science is already difficult enough.

But this turns science into a kind of Museum of Fixed Truths full of “Don’t Touch” signs. Critical research questions are taboo and dangerous for your career. It is not surprising that many scientists do not dare to speak out until they have retired. The journal Nature recently reported that in the last half century the number of disruptive studies – studies that really take a completely different view of the matter – has declined sharply [8]. Much of that decline took place before woke ideology took hold of science. In his farewell speech (1961), President Eisenhower already pointed to the danger that government subsidies for scientific research risked leading to a caste of scientists producing science in line with the wishes of the incumbent political elites.

The current government policy with regard to hazardous substances and ionizing radiation is a good example. This policy has since the 1950s been dominated by the ‘Linear No Threshold’ hypothesis which says that if a megadose of a substance can cause cancer, then one molecule/ray of that substance can do the same. ‘One hit’ will do! This is actually long outdated and should be replaced by a better understanding of hormesis, the recognition that substances that are dangerous in large doses can actually be beneficial for health in a lower dose.

One hit?

Our perception of cancer is dominated by the ‘one hit’ approach. A toxic or radioactive  substance fires a kind of bullet at your DNA, the building plan of your body, that if broken, can grow into a cancer cell. To avoid such ‘bullets’, there exists very restrictive legislation to prevent the occurrence of these substances or radiation. The aim is for zero exposure, but since that is a technical impossibility extremely small quantities in the nanogram or picogram range are tolerated.

In science the ‘bullets’ are called ‘free radicals’, ‘oxygen radicals’ or ‘oxidative stress’ because this is actually about oxygen. The major misunderstanding is however that such a ‘hit’ is a unique, rare, event.

Our body consists of 30 trillion cells, that is 30,000 billion. For comparison: the Milky Way has 100 billion stars. Every cell contains a copy of your DNA, but every cell also contains a mitochondrion , the boilerkettle of the cell. Here the oxygen you take in burns your food to give you energy.

But combustion always creates waste, smoke and ash in your stove, and oxygen radicals in your cells. They provide a continuous and gigantic bombardment of the DNA, 150,000 hits, in each of those 30 trillion cells, daily, throughout your life. Depending on your place on earth (the higher the more), we also receive a daily batch of radiation from space and the soil that adds tens of thousands of ‘hits’ to those 150,000. On average, we endure this (cellular) nuclear war for 75 years, but in the end the radicals win, science speaks of the Free Radical Theory of Aging [10]. A lot of violence in the body, but also a spectacular defense [11].

Starting at the molecular level. Many radicals are ‘captured’, neutralized by the antioxidants in the cell. We make such antioxidants ourselves, they are known as Catalase, SuperOxydeDismutase and Gluthathione Peroxidase (remember!), but many vitamins that we get through our food also do that. And with that in mind, masses of people (including yours truly and numerous scientists) tried to boost those antioxidant reserves by taking extra vitamins. After many years and extensive scientific research, the conclusion is that this does not work. Sometimes the vitamins even increased the risk of death. The radical theory still stands, but how (and if) we can boost the defense is still unclear.

If there are too few antioxidants, the DNA (and other molecules, but we keep it simple) can be damaged. Fortunately, the cell also contains all kinds of ’tools’ to repair it.

If that fails, the cell commits ‘suicide’ (apoptosis) and so avoids to become cancerous. That however can also go wrong and then there is indeed a cancer cell. The problem has then escalated from cell to tissue level and here too the body has all kinds of recovery options. Here the body has several ways to remove that cancer cell, most of the time they do not develop in a tumor for which you need to call a doctor.

A real cancerous growth may then have arisen, but that does not necessarily have to be malignant and if it is, a doctor can still do something about it in 50% of the cases.

It is this internal violence in those 30 trillion cells is now thought to be the main reason why 40% of people will get cancer (about half of them will die from that disease). The everyday environmental pollution and radiation add little to that. Complaining about this is reminiscent of the joke about of the mouse walking over a bridge with an elephant and saying ‘we’re stomping nicely, aren’t we?’

Smoking is actually the only form of ‘pollution’ that produces enough radicals to cause demonstrable damage; we see those cases reflected in the lung cancer statistics. That is apart from exposure to hazardous substances on the work floor, but then it always involves much larger quantities than ‘everyday environmental pollution’.

Hanekamp: ‘Actually, we all die from oxygen. Aging and cancer are related to oxygen damage. Regular experiments have been done on rats exposed to a 95-100% oxygen atmosphere. Survival was no more than a few days, partly due to damaged lungs.

‘De Bijenkorf (large Dutch department store) once wanted to introduce an oxygen bar in Amsterdam . Fifteen minutes of oxygen would be very healthy, they thought. A friend of mine then put a message in the newspaper ‘we think that’s a very bad idea’. If you want to have people with asthma, emphysema, COPD and pulmonary fibrosis, you have to put them on pure oxygen. Fortunately, the Bijenkorf canceled the project.’

Hanekamp continues: ‘The number one method to make you more resistant to oxygen damage is sports, but the strange thing about sports is: your oxygen intake then increases and oxygen is harmful, isn’t it? Yes, but that’s exactly right, because if that oxygen damage increases, your body responds by better defending itself. Exercising too much can again lead to damage. The question is: where is the limit?’

Above I have shown how difficult it is for science to clarify what is dangerous and what you can do about it. The free radical story is exciting, but much is still unclear. Taking extra antioxidants has little effect and there are also situations in which the maligned free radicals do actually good work. So humility is called for, in the words of researcher Azzi [12]: ‘…the use of the oxidative stress notion in complex systems, and even more so in clinical studies, can only be considered a fig leaf used to cover the unknown mechanisms of disease pathogenesis’ 


The practice of using megadoses in laboratory animal experiments assumes that such a substance has virtually the same effect in a low dose as with a high dose. The chance of disease may be smaller, but it remains the same disease. Ordinary people have long known that this is not true. Too much fat, oxygen, salt or alcohol, water, vitamins can be deadly, but a small dose is fine for health, often even indispensable. They have an optimal dose.

It is to the credit of the American professor of toxicology Edward Calabrese [13] that it is becoming increasingly clear that this if it doesn’t kill you it makes you stronger phenomenon actually applies everywhere, all chemicals and radiation behave this way. The pesticide DDT is banned because of its carcinogenicity, but only in high doses. In low doses, it appears to reduce the risk of cancer. The same has been observed with dioxin [14] and even with smoking. The effect at low dose is mainly different from high dose, not necessarily positive. The agents used in chemotherapy appear to promote tumor growth in low doses. So a high dose is good here.

This hormetic effect is usually modest, but appears game-changing in the case of ionizing radiation. In the first half of the last century it was concluded on the basis of animal research with megadoses that radiation is actually dangerous in any dose, both in a high and a low dose. The horrific experiences with the atomic bomb fueled the fear even further and ensured extremely strict standards.

It has since become apparent that this is a misunderstanding (although the standard has not yet been amended). The large dose of the atomic bomb was indeed carcinogenic (although not very much), but the low dose of radiation that people receive in the many places on earth where there is a lot of uranium or thorium in the soil did not appear to be carcinogenic at all, or even protective.

Calabrese discovered that in the early years of the 20th century – long before the atomic bomb scared everyone to the bone – the hormetic effect of radiation was already being used in health care. All kinds of inflammations, pneumonia, whooping cough, turned out to clear up remarkably quickly with a low dose of radiation. Lives were saved, it’s all described in the scientific literature of the time. 

When the Covid pandemic broke out, a few small-scale pilot studies were carried out and they confirmed the positive results of a century before [15]. The scientific community is however very hesitant for further studies in the low dose domain because the LNT tells us that this is always dangerous.

That nevertheless seems very important. It can be deduced from the hormesis research that we are now being protected for a lot of money against substances/doses that are not dangerous or can even promote health. This realization now seems to be breaking through in the radiation world and the discussion about relaxing the standards is in full swing [16].

Safe or unsafe

Science hardly has any way to determine the health effects of long-term exposure to a tiny dose of a certain substance/radiation. There are far too many diseases, types of people and chemicals to answer. A lot of scientific research is being done, but in the end this gives a false sense of security. It can always go wrong somewhere. A lot of people are worried about the chemicals they are getting, but this is also a false sense of insecurity . It just rarely goes wrong. Dramatic changes in consumption patterns seem to lead nowhere. The scandals follow one another but seem to have no effect on public health, life expectancy is still increasing. The most important advice therefore seems to be what people say to each other here in my Christian Dutch village: Don’t Complain But Carry On And Pray For Strength.



[3] Dietary pesticides (99.99% all natural)


[5] Why Most Published Research Findings Are False John PA Ioannidis Published: August 30, 2005


[7] (in Dutch)/

[8] Slowed canonical progress in large fields of science
Disruptive science has declined and no one knows why.



[11] Hormesis by low dose radiation effects: low dose cancer risk modeling must recognize up-regulation of protection. Ludwig E. Feinendegen, Myron Pollycove and Ronald D. Neuman. Medical Radiology, Radiation Oncology

[12] Azzi, A. Oxidative Stress: What Is It? Can It Be Measured? Where Is It Located? Can It Be Good or Bad? Can It Be Prevented? Can It Be Cured?. Antioxidants 2022, 11, 1431.


[14] Tuomisto J, Pekkanen J, Kiviranta H, Tukiainen E, Vartiainen T, Viluksela M, Tuomisto JT. Dioxin cancer risk–example of hormesis? Dose Response. 2006 May 1;3(3):332-41. PMID: 18648613; PMCID: PMC2475943.




We are always urged to eat consciously. Well, how aware are you of the chemical composition of the orange?

(This is merely to indicate that rather than be intimidated by ‘chemical substances’ one does well to embrace things like oranges and similarly also many synthetic compounds – and do so with moderation.)

An orange consists of:
Arginine. Stimulates growth hormone production
amyl alcohol Solvent
H20 Water
Octyl alcohol Used in perfumes and detergents
2-hydroxypropane tricarboxylic acid Irritating substance
Decylaldehyde Possibly carcinogenic
D-Limonene Carcinogenic
Choline Improves the memory of laboratory animals
Methanol Kind of alcohol, can cause blindness and death
Oxalic acid Also found in spinach and to neutralize it we eat an egg with it. An egg with an orange?
Hesperidin Called vitamin P, dietary supplement
Asparagine Carcinogenic, but a deficiency is harmful
Tyramine May be effective against depression
Synephrine Banned as a dietary supplement due to an increase in blood pressure
Fructose A sweeter form of sugar
Sucrose Sugar
Tangeretine Seems to inhibit cancer
Formaldehyde Carcinogenic, same as ‘chipboard gas’ but you also make it yourself.
2 Keto L gulonolacetone Raw material for vitamin C
Polygalacturonic acid Same as pectin (gelling agent) in jam
Anthocyanin Antioxidant, would protect nerves
Carotene Hoped anti-cancer drug. Dissapointing.
Ascorbic acid Vitamin C