Tag Archives: SciBlogs

The ugly truth about critics of “the ugly truth” in science

It’s an interesting issue. Do we sometimes get too defensive about established science? In our efforts to counter the propaganda of the naysayers do we paint an over-optimistic picture of scientific knowledge? Do we sometimes neglect to make a critical analysis of accepted science while at the same time demanding this of the claims made by anti-science critics?


Tracey Brown, director of Sense About Science

Important questions – and don’t tell me they haven’t sometimes caused you to have some uncertainty when defending scientific knowledge from detractors. Of course, you are not alone in this. Tracey Brown, Director of Sense in Science, tackled the subject head on in the annual Sense About Science lecture last week.

The ugly truth

This was the title of her lecture. Perhaps it is a timely warning. We should not be defensive about scientific knowledge – or the policy decisions that rely on that knowledge. We should always be open-minded and critical. And we should always be realistic about the evidence. We should be ready to present and argue for the science – warts and all. Not hiding limitations and uncertainties.

She made these points – and claimed that some of our social policies are based on insufficient information. Or that we sometimes exaggerate the amount and quality of information we have to support these policies. That is the “ugly truth” she highlighted in her lecture.

Unfortunately though, her lecture was a practical example of another “ugly truth” – simple declarations are not enough. One’s criticisms of accepted knowledge are not necessarily correct or justified just because one is being critical. There is still the responsibility to base one’s criticism on facts – and to properly research the area before making critical claims. She based her criticism of at least one social health policy, community water fluoridation, on inadequate knowledge – claims from anti-fluoride campaigners she uncritically accepted.

Falling victim to fluoridation misinformation

Readers can download a podcast of Tracey Brown’s lecture here. I will update this post with a video link when it is available. She discussed fluoridation from 15 – 19 minutes.

Tracey claimed that community water fluoridation (CWF) has very little empirical justification. She gave two reasons:

  1. The social health policy is based only on the original research which is over 70 years old and does not measure up to current scientific standards.
  2. Data shows that the oral health of both fluoridated and unfluoridated countries has improved over recent decades and this has more to do with the use fluoridated toothpaste and improved health care than CWF.

These are, of course, two claims made again and again by anti-fluoride propagandists and campaigners. She could have taken her critique directly from one of Paul Connett’s political submissions to councils considering fluoridation. If she did so, she was irresponsible as there are plenty of experts who could have provided information of far better quality.

I contacted Sense About Science and found out that Tracey used the following papers to “formulate” her comment on fluoride.

Peckham, S. (2012). Slaying sacred cows: is it time to pull the plug on water fluoridation? Critical Public Health, 22(2), 159–177.

Cheng, K. K., Chalmers, I., & Sheldon, T. a. (2007). Adding fluoride to water supplies. BMJ (Clinical Research Ed.), 335(7622), 699–702.

So, let’s consider Tracey’s claims about CWF

  1. The first claim is just silly. Of course, decision makers use the information available at the time – 70 years ago they used the information that was available then. But fluoridation decisions have been made again and again  over the years and it is perfectly natural that decision makers will use the current information for those decisions.The efficacy and safety of CWF have been investigated many times since it was first introduced. Science does not stop after a single study. If Brown had made a simple literature search she would have realised that (see Water fluoridation effective – new study for just one recent example – there are many others).  Or, given that none of us have the time and expertise to be well informed about a wide variety of subjects, she could have consulted somebody with up-to-date knowledge and expertise on the subject. She certainly should not have relied solely on the very one-sided papers by Peckham (a well-known UK anti-fluoride activist) and Cheng et al.
  2. From the audio Brown appeared to use this graphic (below – left image) from Cheng et al., (2007) which is very similar to the one promoted by the anti-fluoride propagandist organisation Fluoride Action  Network. I have discussed this graphic in several articles and in my debate with Paul Connett (download the pdf) It is based on extremely limited WHO data (hence the straight lines), makes comparisons which ignore the multiple factors influencing oral health, and ignores the within-country data which show the efficacy of CWF (such as  for Ireland in my second figure).

Left: Graphic used by Cheng et al (2007). Right: Same WHO data for Ireland with fluoridated and unfluoridated areas represented

The ugly truth about Brown’s lecture

Unfortunately, the “ugly truth” Tracey Brown demonstrated was that even scientists, and supporters of science, can be fooled by the claims of anti-science campaigners if they are too lazy to do their own checking. Perhaps she also demonstrated that even scientists, and pro-science people, can suffer from confirmation bias – just like anyone else. They can sometimes adopt a partisan position which restricts them to considering only the misinformation and distortions peddled by anti-science campaigners.

But it does highlight a dilemma for people like Tracey Brown who might feel they have a “whistle-blower” mission to insist that science, or its practitioners, pull up their collective socks. (I hasten to add it is a “mission” I  support – as I support “whistle-blowers” in general).

The dilemma is that we, as individuals, can not be experts in everything. We are not capable, individually, of making a well-informed critical and objective judgement on all the issues we may have to face in  preparing a lecture like Tracey’s. We have to be careful about relying on our own biases or poorly informed memories. We have to recognise our limitations and not be afraid to consult experts for clarification, updating knowledge or even just getting one’s head around complex issues.

The debunking of many of the claims made by scientific naysayers is often like shooting fish in a barrel. It may not require much checking or even serious engagement with the subject. But it is irresponsible to transfer that lazy approach to serious consideration of real science or the social policies informed by that science.

It is especially irresponsible when speaking as the head of a respected organisation and where listeners may feel justified in seeing the claims as expert and to be trusted. Again we face the fact that as listeners none of us can critically judge a speaker’s claims on all the subjects covered.

Destroying credibility

In this example, I have sufficient knowledge about the science behind CWF to judge this aspect of Tracey’s lecture and see she was mistaken. But what about the other subjects she covered? For example, she claimed that current health advice on cholesterol relies on inadequate research and could be wrong. Do I take her word for it? I certainly don’t feel I should – if she is wrong about CWF she may be just as mistaken about cholesterol.

That also makes me wonder if the Sense About Science organisation is as credible in its pronouncements as I used to think it was.

See also:
Annual Lecture 2015 · Sense about Science
Can you handle the truth? Some ugly facts in science and sensibility – an article by Tracey brown introducing her lecture.

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Fluoride: More scaremongering using drug warnings


Some anti-fluoride campaigners are using drug warnings related to sodium fluoride tablets to claim such warnings should also be placed on the fluoridated water coming out of your tap.

This is silly on two counts:

  1. A tablet sold in a pharmacy is different to water in a tap and such warnings must be appropriate to the tablet and its possible use.
  2. Drug warnings like this are generally all-encompassing and do no imply, by themselves, that there is any danger.

So let’s compare the drug warnings for sodium fluoride tablets (using the web site that the campaigners rely on) with the warnings for other safe substances.

This is the warning for sodium fluoride from the Drugs.com site:

But compare this with the warning for sodium chloride from the drugs.com site.


Using the anti-fluoride campaigners’ logic, they should also be campaigning against sodium chloride – the ordinary salt in so much of our food. Or the chloride in our tap water derived from natural sources and the chlorination treatments.

Their warnings that pregnant women, or people with allergies, shouldn’t be drinking tap water is just naive scaremongering.

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Cochrane responds to misrepresentation of their fluoridation review


Image Credit: Cochrane Oral Health Blog

The latest Cochrane Review on community water fluoridation (CWF) was published in June. Here are a citation and link for those interested:

Iheozor-Ejiofor, Z., Worthington, HV., Walsh, T., O’Malley, L., Clarkson, JE., Macey, R., Alam, R., Tugwell, P., Welch, V., Glenny, A. (2015). Water fluoridation for the prevention of dental caries (Review). The Cochrane Library, (6).

Immediately after publication, anti-fluoride propagandists launched a campaign of misrepresentation and outright distortion of the review’s findings. I dealt with some of this, and commented on the review itself, in the following posts:

The wave of misrepresentation and situations concerned health professionals – some of their on-line feedback and responses are in the Cochrane blog posts – Little contemporary evidence to evaluate effectiveness of fluoride in the water and Our response to the feedback on the Cochrane fluoridation review).

The Cochrane Oral Health Group yesterday published an updated Plain Language Summary (PLS) for the review. If you want to look in detail here is the original version of the review, and here is the abstract and updated Plain Language Summary from the latest version (now online). Their short explanation for this is:

“Following feedback, from a variety of sources, we felt it was necessary to make the language of the PLS simpler.”

This is logical. The PLS is the only part of the Review most policy makers will read. The old version contained too many words like “bias” and references to research “quality” which may have been reasonable to an academic audience but conveyed an entirely different meaning to policy makers who do not have an academic or scientific background. Anti-fluoride campaigners have worked hard to use this in their misrepresentations and distortions aimed at policy makers as well as the public.

Some of the changes

The new PLS does not include the word “bias” and now describes the selection criteria pointing out most studies made after 1975 were excluded (because they did not include initial surveys). Readers will now be more aware that the lack of information in some areas resulted from these strict selection criteria and not from lack of research.

For example, the text:

“No studies met the review’s inclusion criteria that investigated the effectiveness of water fluoridation for preventing tooth decay in adults, rather than children”

has been replaced by

“Within the ‘before and after’ studies we were looking for, we did not find any on the benefits of fluoridated water for adults.”

And the text:

“There was insufficient information available to find out whether the introduction of a water fluoridation programme changed existing differences”

has been replaced by:

“We found insufficient information to determine whether fluoridation reduces differences in tooth decay levels between children from
poorer and more affluent backgrounds.”

Will the misrepresentation continue?

Of course it will. Even the most carefully worded summary can be distorted to misrepresent reported findings. Hopefully, though, these changes will make it harder for campaigners to pull the wool over the eyes of policy makers. The careful reader will now have a better idea of the limitations of the review resulting from the strict selection criteria. Hopefully, they will also be aware that statements like “We found insufficient information . . .” do not mean there is no information. Nor does the inability, within the restricted selection criteria, to find an effect mean there is no effect.

I am disappointed that their changes did not make the situation of dental fluorosis clearer. They do now stress that most of the dental fluorosis studies reviewed “were conducted in places with naturally occurring – not added – fluoride in their water.” But this is not adequate:

“results of the studies reviewed suggest that, where the fluoride level in water is 0.7 ppm, there is a chance of around 12% of people having dental fluorosis that may cause concern about how their teeth look.”

is just not adequate

The choice of 0.7 ppm will be seen as relevant to the concentration used in CWF – but this does not mention that any difference between the  prevalence in fluoridated and unfluoridated areas is very small and not statistically significant. In other words, their comments on dental fluorosis are still not relevant to CWF.

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ChildSmile dental health – its pros and cons


There is some local interest in the Scottish ChildSmile dental health programme. Partly because anti-fluoride campaigners are promoting it to local bodies as an alternative to community water fluoridation (CWF). Their interest is possibly due to the opt-in nature of the programme which they see as satisfying there demands for “freedom of choice” (in this case the choice means excluding their own children from the programme which, after all, does include fluoride treatments).

However, health professionals in the UK are more balanced in their opinions. While welcoming ChildSmile they do not see it as an argument against CWF – rather as “the next best thing – a rather expensive substitute for the fluoridation schemes that have never been introduced.”

I have written about the ChildSmile programme before (see Fluoride debate: Ken Perrott’s closing response to Paul Connett?). But here is some more detail I have picked up from discussion online with health professionals.

What is the ChildSmile programme?

On the surface, the ChildSmile programme supplies children with toothbrushes and toothpaste:

“The core programme involves supervised daily toothbrushing for all Scottish three and four year olds attending nursery schools (but not those who don’t attend nurseries). This has been extended to five and six year olds in primary schools in those areas (not necessarily across entire local authorities) counted as being among the 20% most deprived in Scotland.”

Data suggest that about 82% of three and four-year-olds are participating. The children who do not take part do not benefit.

ChildSmile also includes twice-yearly application of fluoride varnish to children’s teeth.  The programme 2013/2014 targets included this:

“At least 60% of 3 and 4 year old children in each SIMD quintile to receive at least two applications of fluoride varnish per year by March 2014.”

In addition to toothbrushing and varnishing, Childsmile involves health education initiatives based principally on public health nurses and health visitors attaching themselves to particular schools in order to give oral health advice to children and parents. Subject to parental consent, they also arrange for children who are not registered with a dentist to undergo check-ups and, if necessary, treatment.

Is it a substitute for CWF?

Not really, but health professionals see it as the “next best thing.” Appropriate for situations where there is no CWF. But it only covers children – and then only those children whose parents give consent (many don’t). In contrast, CWF benefits adolescents and adults, as well as children. Families can, of course, “opt out” od CWF (by using water filters or different sources), but numbers will be lower than those excluded by “opt-in” procedures.

It is wrong to see such programmes as alternatives to, or separate from, CWF. Elements of the ChildSmile programme were already present before ChildSmile was introduced. Similar elements will also be common in countries like New Zealand.

Is it effective?

Childsmile was introduced in 2008 so it is a little early to judge its effectiveness. Scottish children’s dental health has improved and the programme most likely has assisted that.

For example, 58% of five-year-olds were free of decay in 2008, compared with 68% in 2014. The average decayed, missing and filled teeth (dmft) score for this age group has fallen over that period from 1.86 to 1.27.


However, there does not seem to have been a reduction in dental health inequalities between children from different social groups in Scotland. In 2008, 42% of children from the most socially deprived quintile of Scottish five-year-olds were free of decay compared with 73% of those from the least deprived quintile. In 2014, 53% of five-year-olds in the most deprived quintile were free of decay compared with 83% of those from the least deprived quintile.


According to the Scottish National Dental Inspection programme the absolute inequality between the most and least deprived children remains at 30% (comparing percentages of children without tooth decay), according to surveys conducted in 2008, 2010, 2012 and 2014.

Another concern is that children in the most deprived quintile of five-year-olds have not reached the national target set in 2010 that 60% of them should be free of decay.

Of course, the ChildSmile programme has no effect on the oral health of  current adolescents and adults.

What about the cost?

ChildSmile is far less cost-effective than CWF. Let’s compare the cost of CWF in England with the costs for the ChildSmile programme in Scotland

CWF serves 6 million people in England, costs around £2.1 million a year and is benefiting everyone with natural teeth, regardless of age, education or socioeconomic status. It benefits all children. So the cost per person of is around 35 pence per annum, although if we exclude people with no natural teeth it is likely to be a little higher than that – an average cost of about 40 pence per person benefiting.

If we take a narrow view and assume only children and adolescents aged 0 to 17 (21% of the population in England ) benefitted from CWF the cost would apply to around 1.26 million out of the 6 million supplied with fluoridated water. On that basis, the cost of CWF would be £1.67 per year for each child benefitting.

In contrast:

The total national ChildSmile budget for 2013/14 was £14,956,000, according to a statement by the Minister responsible to the Scottish Parliament in July 2013. This covers  everything attributable to Childsmile – the toothbrushing programme, plus targeted varnish applications and associated oral health education initiatives.  Assuming that around 120,000 Scottish children aged between three and six are benefiting, it works out at a cost of around £125 per child per annum.

Compare the Childsmile costs of around £125 per child per annum with the CWF costs of about 40 pence per person per annum or even £1.67 per year for each child benefitting. CWF is obviously many times less expensive that ChildSmile.

What is the attitude of Scottish dentists?

The British Dental Association supports CWF and in Scotland has come out publicly to call for communities to move towards introducing water fluoridation. That position undermines the arguments of New Zealand anti-fluoridation groups claiming that Childsmile is an adequate substitute for water fluoridation. The professional body representing dentists in Scotland does not see it that way.

The BDA in Scotland points out that CWF would be beneficial to children and elderly people. It argues that water fluoridation “would complement the Childsmile programme” by helping cut the overall burden of tooth decay and reducing dental health inequalities in the elderly. We could look at it another way and see that a Childsmile programme could complement water fluoridation. After all, we must remember that initiatives such as Childsmile rely on personal compliance and that they benefit only those taking part. They give no benefit for the rest of the population, unlike CWF.

CWF and ChildSmile are are not mutually exclusive. Children in fluoridated areas should be encouraged to brush their teeth regularly with a fluoride toothpaste and to receive dental check-ups. Bear in mind, also, that components of a ChildSmile programme, such as supervised toothbrushing, were in use in parts of Scotland before the introduction of the full programme. Elements of the ChildSmile programme will also be in current use in New Zealand.


Despite claims of anti-fluoride propagandists, the ChildSmile programme is not a simple alternative to CWF. And it is wrong to see it as such in New Zealand.

It is far less cost-effective – the Scottish programme costs around £125 per child per annum compared with 40 pence per person per annum (or £1.67 per year for each child benefitting when benefits to adults are excluded) and therefore far less likely to be put in place as an alternative to CWF.

ChildSmile is an “opt-in” programme so its coverage is far lower than CWF which is an “opt-out.” This is important when social differences in oral health are important.

However, the contact between children and their families on the one hand and public health nurses, health visitors and dentists on the other, is very valuable and may have wider benefits than oral health alone. (I am thinking of problems caused by child neglect and abuse).

I think these sort of programmes are socially very helpful and strongly support them. The cost is, of course, a limiting factor. However, elements of such social programmes may be possible within budget constraints that health authorities face.

Health programmes like ChildSmile, or elements of that programme, can be very effective even in areas where CWF exists. They can give that extra boost to the oral health of children and can, therefore, complement CWF.

There are many areas where CWF is not feasible because of low population density, lack of suitable water reticulation systems or local political opposition to CWF. I believe that programmes like ChildSmile, or parts of that programme, can be very helpful in those situations. Northland and particularly NZ’s Far North are obvious examples.

Finally, let’s not be diverted by the programme name. I am sure that elements of the Scottish ChildSmile programme are already in place in New Zealand, or parts of New Zealand. Given the costs of such programmes, and budget limitations, these programmes do have the advantage that they can be targeted to regions or social groups where the need is the greatest.

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Should all scientists really be militant atheists?

As my title implies this post discusses the New Yorker article by Lawrence Krauss – All Scientists Should Be Militant Atheists. I basically agree with his analysis but feel he has left himself open to an unwarranted criticism often made of the scientific approach.

The headline is very provocative – and was clearly meant to be. The term “militant atheist” is just silly. But it did smoke out the expected criticism from the faithful (for example Should Scientists Be Atheists? More Nonsense From Lawrence Krauss by Kelly James Clark from the Brooks College and Kaufman Interfaith Institute). These critics attempt to avoid Krauss’s central complaint about the unwarranted privilege religion gets in our society (to the extent that when a law-breaker like Kim Davis is punished there are loud complaints of Christians being persecuted or Christian beliefs being made illegal). And they also attempt to denigrate his point that the scientific process should not be perverted in its exploration of the evidence and application of reason by demands of unjustified respect for belief or faith when it conflicts with evidence.

The people who wish to protect this religious privilege – even in scientific investigation – are the ones who describe any criticism of their stance as “militant.”

Rejecting the “sacred” justification

Krauss dismissed the demand for respect with:

“The problem, obviously, is that what is sacred to one person can be meaningless (or repugnant) to another. That’s one of the reasons why a modern secular society generally legislates against actions, not ideas. No idea or belief should be illegal; conversely, no idea should be so sacred that it legally justifies actions that would otherwise be illegal.”

Applying this to the scientific process he wrote:

“In science, of course, the very word “sacred” is profane. No ideas, religious or otherwise, get a free pass. The notion that some idea or concept is beyond question or attack is anathema to the entire scientific undertaking. This commitment to open questioning is deeply tied to the fact that science is an atheistic enterprise. “My practice as a scientist is atheistic,” the biologist J.B.S. Haldane wrote, in 1934. “That is to say, when I set up an experiment I assume that no god, angel, or devil is going to interfere with its course and this assumption has been justified by such success as I have achieved in my professional career.” It’s ironic, really, that so many people are fixated on the relationship between science and religion: basically, there isn’t one. In my more than thirty years as a practicing physicist, I have never heard the word “God” mentioned in a scientific meeting. Belief or nonbelief in God is irrelevant to our understanding of the workings of nature—just as it’s irrelevant to the question of whether or not citizens are obligated to follow the law.”

Unfortunately his use of Haldane’s quote – together with his provocative title “All Scientists Should Be Militant Atheistsconveyed the impression that scientists should approach their investigation with a bias that already rejects some possible outcomes.

No relationship between science and religion

However, that was not Krauss’s claim. He used the term “atheist” in its negative sense (not theist) – not implying an imposition of any preconceived beliefs or ideas.

His real point was expressed in his point that basically there is no relationship between science and religion:

“In my more than thirty years as a practicing physicist, I have never heard the word “God” mentioned in a scientific meeting. Belief or nonbelief in God is irrelevant to our understanding of the workings of nature—just as it’s irrelevant to the question of whether or not citizens are obligated to follow the law.”

Clark, more or less agrees with Krauss’s central claim  when he retaliated with:

“Scientists can be religious, liberal, communist, or even gay. But when they’re doing science, those beliefs are irrelevant and should not affect the practice of science. So be it. Scientists are under no obligation to affirm the opposite of any of those beliefs; and they needn’t deny them–but they should not bring those beliefs into their scientific practices.”

And in effect, he also agrees with Haldane – when we take into account the flippant words Haldane used. Of course scientists “assume that no god, angel, or devil is going to interfere” with their experimental investigations. In the same way they assume that goblins, fairies, and all sorts of mythical creatures will not interfere.

Mind you, I really wonder at his assertion that a scientist need not deny her beliefs when the evidence shows them wrong. Surely that is unhealthy?

Scientists must be completely open to all and every outcome of their investigation – and perhaps they should even be “militant” about this rejection of blinkers. It is one thing to start with a strong, empirically supported, acceptance of the laws of thermodynamics – but quite another to be restricted by a strong belief in a myth without any evidential support.


The “god idea” is just such a myth. It is never expressed even as a concrete hypothesis (which implies testability) let alone a rational theory with an evidential base.

Unfortunately, for much of history humanity’s attempts to investigate and understand the world have been hampered by an a priori insistence that investigation be based on such myths. Modern science has broken away from such bonds – and that is why it is so overwhelmingly successful.

Yet, there are people who work hard to reapply those bonds. Who wish to introduce  a”theistically-correct” approach to science which denies the need for evidence and (what amounts to the same thing) insists that “supernatural explanation’ are accepted.

People like Krauss are standing up to this pressure – and good on them. We need people who are prepared to be “militant” in this way.

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The Alternative Medicine Racket

We are so used to the bad press that pharmaceutical companies and the health service get that it is worth standing back and having a critical look at what the “natural”/alternative health industry gets up to.

And that is not jut the pseudoscience and magical claim. It also the political manipulation and manoeuvring.

This video is quite timely.

Source: The Alternative Medicine Racket « Science-Based Medicine

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The chemical party

Just imagine teaching chemistry this way.

I guess you would have to lay off the juice, though. Otherwise, there could be some impossible bonding – and student recall would be low.

Thanks to: Sciencegasm shared Universitetet i Oslo (UiO)’s video.

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A job with a view – but not for the clumsy

Here is a breathtaking GoPro video of a spacewalk by two Russian cosmonauts, Mikhail Korniyenko and the record-breaking Gennady Padalka, outside the International Space Station (ISS). (Padalka recently set a new record of 879 cumulative days spent in space.)

It is certainly an exciting job – and what a view!

But I’m amazed at all the fiddly stuff on the outside of the ISS.  I wouldn’t have the confidence – too scared of being caught up in all the wires and gadgets.

Although, there would not be a problem with dropping tools and gadgets.

See how Gennady Padalka, or is it Mikhail Korniyenko, disposes of the replaced item at the end!

Thanks to: GoPro captures Russian cosmonaut duo performing spectacular spacewalk

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My talk to the Reason & Science Society – an invite

RSSAuckland readers are welcome to come along to a talk I am giving at Auckland University next Thursday.

The Reason and Science Society (RSS) hosting the talk. It’s called “The Case for Community Water Fluoridation with Dr Ken Perrott”. Details are:

Day: Thursday 17th September
Time: 6:00 PM – 8:00 PM.
Location: Room 206-315, Arts 1 building, University of Auckland
Map of the talk location: https://drive.google.com/open?id=0B0IBXUx5pSLaNVYzS2tGMnBFTEE

About this talk:
Community water fluoridation continues to be a controversial in New Zealand. Thames is the latest community to face this issue in an October referendum. Local bodies are frustrated by the lobbying the bombarded with on this issue and are asking central government to take responsibility for it.

Many of the claims made about fluoridation are misleading and scientific research is often distorted to support these claims. Dr Ken Perrott will describe what the science is really saying about community water fluoridation.

About the speaker:
Dr Ken Perrott is a retired research scientist. He is a scientific advisor for Making sense of Fluoride.

Event page (you need to join the RSS group to view it):

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Why the internet annoys chemists

Here are some of chemist’s pet peeves chemists about discussion on social media and the internet in general. The list is from the article  5 simple chemistry facts that everyone should understand before talking about science posted on the blog The Logic of Science.

Everyone who has attempted to discuss issues like vaccination or fluoridation with opponents will have come across these arguments which the author describes as “based on a lack of knowledge about high school level chemistry.” This ignorance doesn’t seem to prevent the perpetrators of these arguments presenting with extreme confidence and fervour. When challenged they often question the scientific credibility of their critics and urge them to “do some research!”

1: Everything is made of chemicals

chemical free

The article points out:

“This seems like a simple concept, but many people seem to struggle greatly with it, so let’s get this straight: all matter is made of chemicals. You consist entirely of chemicals. All food (even organic food) consists entirely of chemicals. Herbal remedies consist entirely of chemicals, etc. So, when someone says something like, “I don’t vaccinate because I don’t want my child to be injected with chemicals,” they have just demonstrated how truly uninformed they are, and you can be absolutely certain that they don’t know what they are talking about because all matter is made of chemicals.”

Yet these arguments and terms like “chemical-free” seem to have gripped public consciousness. The only thing “chemical-free” is empty space!

A particular peeve of mine is the attitude advertisers seem to have that by declaring their product “chemical-free” they can get away with not identifying the real chemicals in their product. Recently at the supermarket I searched in vain for an indication of the chemicals in a package of sea salt. Genuinely intrigued to find what other salts were present, together with the majority sodium chloride, all I could find was the description that the product was “chemical-free!”

2: The dose makes the poison


“There is no such thing as a toxic chemical, there are only toxic doses. Let me say that again: all chemicals are safe at a low enough dose, and all chemicals are toxic at a high enough dose. This is a fundamental fact that people in the anti-science movement routinely ignore.”

Yet look at how the anti-science movement ignores this simple fact. Anti-fluoridationists who seem to think that have a foolproof argument by waving Material Safety Data Sheets for water treatment chemicals like fluorosilicic acid and sodium fluorosilicate. Such sheets supply information for people manufacturing, handling and transporting the concentrated chemical. They have absolutely no relevance for the person drinking the water coming out of their tap.

A little more sophisticated (although only a little) are the arguments based on scientific studies of rats administered chemicals at concentrations far higher than confronted by the ordinary consumer. Anti-fluoridationists spout so  much hot air citing studies of rats administered 100 ppm F or more in their drinking water to claim that drinking fluoridated water which has an F concentration of 0.7 ppm is harmful!

“The importance of this fact cannot be overstated. No chemical is inherently safe or inherently dangerous. So, the next time that someone tries to scare you about the “toxic chemicals” in your food, medicine, vaccines, detergents, etc. ask them for two pieces of information:

  1. What is the toxic dose in humans?
  2. What is the dose in the product in question?

Those two pieces of information are absolutely crucial to evaluating the safety of the product. You simply cannot know whether that chemical is dangerous without knowing the dose in the product and the dose at which it becomes toxic.”

3: There is no difference between “natural” and “synthetic” versions of a chemical

“I often hear people claim that “synthetic” chemicals (a.k.a. chemicals made in a lab) are not as good for you as their “natural” counterparts. The reality is that this represents a misunderstanding of literally the most fundamental concept of chemistry. The most basic unit of matter is the atom, and there are several different types of atoms known as elements. We combine these elements to make various molecules, and the combination of elements determines the molecule’s properties. The process by which those elements were combined is completely and totally irrelevant to how the final chemical behaves.

For example, water (a.k.a. dihydrogen monoxide) consists of three atoms: 2 hydrogens and 1 oxygen (hydrogen and oxygen are both elements). There are literally thousands of different chemical reactions that will produce water. In other words, we can make water thousands of different ways, but water always behaves in exactly the same way no matter how it was formed because it always consists of the same three atoms. Further, if given a vial of pure water, there isn’t a chemist anywhere in the world who could tell you how that water was produced because it would be completely identical to all of the other water everywhere on the planet. So, as long as the chemical structure is the same, it doesn’t matter if the chemical was extracted from a plant or synthesized in a lab.”

Yet, how often am I told that fluoridating chemicals are bad because they are “industrial,” “manufactured” or “synthetic.” The implication being that if we just dug these minerals out of the ground and dumped them in the water things would be quite OK. Of course, these people ignore the impurities present in “natural” ores and chemicals. Purification to a standard suitable for use in foods and drinking water requires chemical processing. Does treatment converting an “unsafe” ore or chemical to a safe (for consumption) chemical somehow make the chemical unsafe because it is now synthetic?

4: “Natural” chemicals are not automatically good and “artificial” chemicals are not automatically bad

“I often encounter people who will claim to agree with everything that I have said thus far, but they still insist that “artificial” chemicals (a.k.a. chemicals that simply are not found in nature) are bad for you and shouldn’t be consumed, injected, etc. There are several critical problems here. First, remember again that all chemicals are dangerous at a high enough doses and safe at a low enough dose. That is just as true for artificial chemicals as it is for natural chemicals. Second, this claim is nothing more than an appeal to nature fallacy. Nature is full of chemicals such as cyanide and arsenic that are dangerous at anything but a very low dose, so there is no reason to think that the “naturalness” of a chemical is an indicator of its healthiness.

Further, remember that chemicals are nothing more than arrangements of elements. There is absolutely no reason to think that nature has produced all of the best arrangements or that we are incapable of making an arrangement that is safe or even better than what nature produced. I constantly hear people say that we cannot improve on nature, but that is an utterly ludicrous and unsupportable claim, and I would challenge anyone to give me a logical syllogism that backs it up. Really think about this for a minute, if you are of the opinion that artificial chemicals should be avoided, try to defend that position. Ask yourself why you think that. Can you give me any reason to think that they are bad other than simply that they aren’t natural (which we have just established is a fallacy)?”

This nature = good, articifial=bad,  argument may appeal to the emotions of the chemo-phobic consumer, but it is just not rational.

5: A chemical’s properties are determined by the other chemicals that it is bound to

This is so obvious to anyone who has a rudimentary understanding of chemistry – but surprisingly it still gets challenged. How often have I come across anti-fluoride campaigners referring to fluorine containing chemicals like sarin gas (a chemical weapon), Prozac (a drug), hydrofluoric acid (a corrosive acid) – or even to fluorosilicates (used to treat water but decomposing on dilution) as if their properties were relevant to the fluoride in drinking water.

“Chemical compounds are made by combining different elements or even molecules, and the final product may not behave the same way as all of its individual parts. Sodium chloride is a classic example of this concept. Sodium is extremely reactive and will literally explode if it contacts water, and chlorine is very toxic at anything but an extremely low dose. Nevertheless, when we combine them we get sodium chloride, which is better known as table salt. Notice that table salt does not have the properties of either sodium or chlorine. It does not explode when it contacts water and you cannot get chlorine poisoning from it no matter how much of it you eat. The combination of those two elements changed their properties and it would be absurd to say that “salt is dangerous because it contains sodium.” The sodium in salt no longer behaves like sodium because it is bound to the chlorine. Therefore, when you hear a claim that something contains a dangerous chemical, make sure that the chemical isn’t bound to something that makes it safe.”

And therefore:

“So, claiming that “mercury is dangerous and vaccines contain mercury, therefore vaccines are dangerous” is no different from claiming that “sodium is dangerous and salt contains sodium, therefore salt is dangerous.””

Most dangerous and toxic  chemicals contain hydrogen, carbon, oxygen and/or nitrogen. That doesn’t make pure water toxic because it contains oxygen and hydrogen. Proteins, starches and sugars toxic because they contain hydrogen, oxygen carbon and nitrogen. Or the air we breath toxic because it contains oxygen and nitrogen.

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