June ’21 – NZ blogs sitemeter ranking

I notice a few regulars no longer allow public access to the site counters. This may happen accidentally when the blog format is altered. If your blog is unexpectedly missing or the numbers seem very low please check this out. After correcting send me the URL for your site meter and I can correct the information in the database.

Similarly, if your blog data in this list seems out of whack, please check your site meter. Usually, the problem is that for some reason your site meter is no longer working.

Sitemeter is no longer working so the total number of NZ blogs in this list has been drastically reduced. I recommend anyone with Sitemeter consider transferring to one of the other meters. See  NZ Blog Rankings FAQ.

This list is compiled automatically from the data in the various site meters used. If you feel the data in this list is wrong could you check to make sure the problem is not with your own site meter? I am of course happy to correct any mistakes that occur in the automatic transfer of data to this list but cannot be responsible for the site meters themselves. They do play up.

Every month I get queries from people wanting their own blog included. I encourage and am happy to respond to queries but have prepared a list of frequently asked questions (FAQs) people can check out. Have a look at NZ Blog Rankings FAQ. This is particularly helpful to those wondering how to set up sitemeters. Please note, the system is automatic and relies on blogs having sitemeters which allow public access to the stats.

Here are the rankings of New Zealand blogs with publicly available statistics for June 2021. Ranking is by visit numbers. I have listed the blogs in the table below, together with monthly visits and page view numbers. Meanwhile, I am still keen to hear of any other blogs with publicly available sitemeter or visitor stats that I have missed. Contact me if you know of any or wish help adding publicly available stats to your bog.

You can see data for previous months at Blog Ranks

Subscribe to NZ Blog Rankings Subscribe to NZ blog rankings by Email Find out how to get Subscription & email updates

Rank Blog Visits/month Page Views/month
1 The Daily Blog 90174 370305
2 13th Floor 24319 28107
3 Liturgy 16540 20492
4 SciBlogs 14209 23310
5 Tikorangi: The Jury Garden 11009 12385
6 Bill Bennett 9633 10618
7 Homepaddock 7336 8010
8 Creative Maths 6686 7951
9 Cycling in Christchurch 5557 6451
10 Free range statistics 5456 7659
11 Music of sound 3811 4713
12 Offsetting behaviour 3576 4155
13 Lost in silver fern 3376 5177
14 Jontynz 2899 3513
15 Woodleigh Nursery 2649 4602
16 The Meaning of Trees 2151 3372
17 Nom Nom Panda 2028 2160
18 Fields of Blood 1551 1665
19 Talking Auckland 1246 1402
20 Open Parachute 1176 1446
21 The Global Couple 1169 1297
22 Anglican down under 1143 1343
23 Sarah the Gardener 1132 1451
24 Reading the maps 1029 1600
25 The Woolshed Wargamer 960 1585
26 TVHE 933 1122
27 No Minister 885 969
28 A communist at large 834 978
29 Muffin-Mum 695 737
30 Hot Topic 633 702
31 Rodney’s Aviation Ramblings 577 628
32 Off the couch 560 648
33 Pdubyah – a life just as ordinary 525 561
34 Aotearoa: A wider perspective 524 527
35 Keeping Stock 475 475
36 Home education Foundation 438 499
37 Vomkrieg 391 486
38 Quote Unquote 381 421
39 AmeriNZ 332 507
40 Aughts and Oughtisms 304 490
41 Stratford Aerodrome 301 379
42 Fun with Allergy Kids 298 383
43 Kiwi Cakes 294 335
44 Economics New Zealand 260 322
45 Tales from a Caffeinated Weka 246 249
46 Communication, Church, Society 240 300
47 Climate Justice Taranaki 231 317
48 Mrs Cake 218 294
49 New Zealand Conservative 211 214
50 Tauranga Blog 193 196
51 Perissodactyla 192 210
52 Cambridge NZ 186 256
53 Creative Voice# 169 352
54 Sparrowhawk/Karearea 161 186
55 Media Sport and Other Rantings 160 164
56 Anne Free Spirit 141 269
57 AnneKcam 131 187
58 Undeniably Atheist 129 131
58 Social Media & the 2014 Election 129 135
60 Room 5 @ Melville Intermediate School 100 122
61 Room One @ Auroa School 94 118
62 Eye on the ICR 87 96
63 Mountains of Our Minds# 85 122
64 Ideologically impure 83 100
65 goNZo Freakpower Brains Trust 79 80
66 Save our Schools NZ 78 86
67 Dad4justice 73 79
68 Glennis’s Blog Page# 71 108
69 The Catalyst 67 100
70 kiwi simplexity 64 65
70 My thinks 64 65
72 Get Out Gertrude! 59 60
73 John Macilree’s Weblog# 58 62
74 Right Reason 47 47
75 Cut your hair 46 49
76 Samuel Dennis 45 46
77 Put ’em all on an island 43 47
78 Nelsonian’s life 42 48
79 Socialist Aotearoa 41 41
80 sticK 40 40
80 ElephaNZa 40 46
82 Unity Blog 38 38
83 Exile in New zealand 34 37
84 Family integrity 33 33
85 Wokarella 32 40
86 Glenview 9 29 30
87 Software development and stuff 27 31
87 James McKerrow – Surveyor 1834-1919# 27 28
89 Bob McKerrow – Wayfarer 22 22
89 Room 24, 2012 22 22
91 MartinIsti Blog 21 22
92 Quietly in the backgroud 20 21
92 The Official Ebenezer Teichelmann Blog# 20 20
94 Journey to a mini me 19 20
94 bread and pomegranates 19 39
96 Sacraparental 14 15
96 Chris Jillet – Mountaineer# 14 14
98 John Macilree’s Blog 13 13
98 Wellington Chic 13 13
100 University of Otago, Law Library Blog 12 12
100 Look, Think, Make 12 12
102 Episto 11 11
102 Taradale Blog# 11 11
104 ah! New Year’s Resolution 10 10
105 Four seasons in one 9 9
106 The Well read Kitty 8 8
106 MandM 8 8
108 SmallTorque 7 11
109 Warrington Taylor# 6 6
110 New Zealand Indian Fine Arts Society 5 5
110 kiwiincanberra 5 5
112 New Zealand female Firefighter calendar 4 4
112 Utopia – you are standing in it 4 4
114 Helen Heath 3 3
114 Politicalisation 3 3
116 Carolyn’s blog 2 2
116 Einstein Music Journal 2 3
118 Earth is my favourite planet 1 1
118 High voltage learning during the Christchurch earthquakes 1 1
118 The Little Waaagh! That Could 1 1
118 Sharlene says 1 1

Anti-fluoridation group tells porkies about NZ fluoridation review

FFNZ spreads misinformation about the NZ fluoridation review – yet again

New Zealand opponents of community water fluoridation (CWF) are at it again. Their only response to the recently upgraded fluoridation review is to call it “propaganda” and to completely misrepresent it. But it’s interesting to look at their misrepresentation because it does highlight a basic flaw in the studies the anti-fluoride campaign has been promoting.

Fluoride Free NZ (FFNZ) claim in their recent press release (Chief Science Advisor Appears To Deliberately Mislead On Fluoride Science):

“among the many mistakes and reliance on out-of-date science, the most glaring issue is that she refers to two of the best studies ever carried out on fluoride and IQ (Mexico and Canada) as “having high prenatal exposure”. This is probably the most egregious misrepresentation in the review and hard to believe it was not done to purposely misrepresent.”

But this is completely false. In discussing the Canadian study the review actually says it:

“found that the mother’s exposure to fluoride during pregnancy was associated with lower IQ scores [54] in boys (but not girls), even at optimally fluoridated water levels (i.e. between 0.7-1.2 mg/L). If this finding were replicated in robust studies, it would potentially be concerning as Aotearoa New Zealand recommends fluoridation of water between 0.7 and 1.0 mg/L. There was significant and valid criticism of aspects of the study by many subject-matter experts when it was released (see for example, ‘expert reaction to study looking at maternal exposure to fluoride and IQ in children’). The study used sub-group analysis to find an association that is not explained in the paper (i.e. why were only boys affected [55] and why verbal IQ was not impacted), the effect appeared to be driven by the minority of participants that had much higher fluoride exposures (i.e. higher than those in Aotearoa New Zealand).” [My emphasis]

So the review does refer to the Canadian study being conducted at “optimally fluoridated water levels (i.e. between 0.7-1.2 mg/L)” – not at the elevated levels leading to “high prenatal exposure” that FFNZ falsely (and “egregiously”) asserts. But the key assertion by the NZ fluoridation review is that “the effect appeared to be driven by the minority of participants that had much higher fluoride exposures.”

Outliers lead to false conclusions

Canadian study promoted by opponents of community water fluoridation relies on just a few outliers  Image credit: The problem with outliers

It’s quite simple really. Even within a group exposed to levels of fluoride expected with CWF there can be some individuals who receive higher exposes (f0r instance through consumption of fluoridated toothpaste or industrial pollution).

Looking at the data in the Canadian study in the image below taken from Green et al (2019) we can see that while most data points are clustered together at urinary F concentrations less than 1 mg/L there are a few data points at high urinary F concentrations and these do appear to drive the relationship they report – particularly for boys.

For the more statistically inclined reader, the table below summarises the relationships obtained by linear regression analysis. While the authors reported a statistically significant relationship for all the urinary fluoride concentrations up to 2.5 mg/L when the four high-end outliers (> 2.0 mg/L) are removed there is no significant relationship.

So I think the suggestion of the updated NZ fluoridation review is quite correct. The effect reported by Green et al (2019) is driven by just a few outliers and there is no statistically significant relationship when those four outliers are removed. That gives a false impression of the effect of CWF and in fact, their data shows absolutely no difference between IQ in fluoridated areas and unfluoridated areas.

Note 1: There is a discrepancy in the first table between the relationship reported by Green et al (2019) and that based on digitally extracted data points. Unfortunately, only 82% of the claimed data points could be extracted which is strange as usually close to 100% of data points can be extracted. Other commenters have reported the same problem. So it appears the authors have not included all their data in the figures and they have so far refused to make their data available for independent statistical analysis.

Although the Green et al (2019) paper did not cite R-squared values in her Master thesis did cite an R-squared value of 0.049 for boys. The low R-squared values (meaning the inclusion of the coefficient explains at most only a few per cent of the variation) and relatively high regression standard errors suggest that the reported coefficients are meaningless (they can be ignored in any model) – even if statistically significant.

Note 2: In case anyone suggests I have neglected the FFNZ reference to the Mexican study. That study took place in an area of endemic fluorosis and the authors have no record of the water fluoride levels mothers were exposed to. Bashesh et al (2017) reported:

“By virtue of living in Mexico, individuals participating in the study have been exposed to fluoridated salt (at 250 ppm) and to varying degrees of naturally occurring fluoride in drinking water. Previous reports, based on samples taken from different urban and rural areas, indicate that natural water fluoride levels in Mexico City may range from 0.15 to 1:38 mg/L. Mean fluoride content for Mexico  City’s water supply is not available because fluoride is not reported as part of water quality control programs in Mexico.

Despite this, the Bashash study is often unjustly included with studies from areas of CWF by coauthors of Bashash and Green (see for example Farmus et al 2001). Anti-fluoride activists almost always make this mistake. Sure, they may attempt to justify their treatment of Bashash et al (2017) as relevant to CWF based on urinary fluoride values. But these a subject to so much variation and usually involve different collection and correction methods making comparison unjustified.

Similar articles

Opponents of fluoridation all at sea with new legislation

Opponents of community water fluoridation (CWF) should be supporting the proposed fluoridation legislation instead of organising opposition to it.

Think about it.

If Fluoride Free NZ (FFNZ) was honest in its claim that they are “New Zealand’s leading advocate for science in the fluoridation debate” (see their press release  Open letter to Hon Andrew little, Minister of Health) then they should be supporting science rather than ideology and insist on the best scientific scrutiny of information relating to fluoridation.

If they honestly accept the claims of those cherry-picked anti-fluoride scientists they are quoting in their social media memes then they should welcome the opportunity to expose the research of those scientists to a proper critical review.

With scientific backers like this, opponents of community water fluoridation should be welcoming the new fluoridation legislation (example of social media memes promoted by the Fluoride Action Network)

And they should welcome the proposal that the proper place for such a scientific review is the office of the Director-general of health which can call on the best scientists for information and review of the evidence. That proposal is an integral part of the draft legislation which requires that the Director-General must consider the scientific evidence related to community water fluoridation before making a direction that CWF be introduced or stopped in a region (see clause 116E : Director-General may direct local authority to add or not to add fluoride to drinking water in the Supplementary Order Paper).

So, it appears strange that instead of welcoming the new legislation FFNZ is mobilising their supporters to oppose it. And their US colleagues at the Fluoridation Action Network are pouring their resources into the FFNZ campaign.

But why? It is ridiculous for pro-science people to campaign to retain the old system where the evaluation of evidence and decisions on CWF were made by scientific and political naive councillors in local bodies. Councillors who could be easily captured by activists and fooled by their misrepresentation of the science., Councillors who are more concerned with their next election or chances of claiming the Mayor’s job than any science. And councillors who are already predisposed to the claims of the activists, who may indeed be activists themselves, who were more concerned with ideological orientation than any science.

If the fluoridation opponents organised by FFNZ are really “leading advocates for science” and want recent research they are promoting to be considered in fluoridation decisions then they would be supporting the new legislation rather than opposing it.

Ideological distortion of science

I really wonder at a group of ideologically motivated people making submissions promoting their understanding (or misunderstanding) of the science to the Parliamentary Health Committee when that committee is simply not tasked with considering the science. Its job is to consider proposals for the reorganisation of the mechanism for making fluoridation decisions – nothing to do with science itself.

Instead of wasting their submissions on this bill, they should be saving them for promotion of their beliefs about what the science claims to the Director-General of Health and his/her staff. Once this bill is passed the Director-General of Health’s office should be a great place for these claims to be properly considered and reviewed.

That would be a vast improvement on the old situation when they took their arguments to scientifically and politically naive local body councils. Or brought in US anti-fluoridation spokesmen to speak to audiences of homoeopaths, head massagers and other alternative health advocates and their followers.

Or perhaps I am the naive one. Perhaps fluoridation opponents prefer to make their arguments to those local body councillors instead of scientifically capable people. Perhaps FFNZ is dishonest to claim they are ““New Zealand’s leading advocate for science in the fluoridation debate.” 

Similar articles

 

Update of NZ fluoridation review timely and useful

Image credit: Kurt:S/Flickr (CC BY-SA 2.0).

An updated New Zealand scientific review of community water fluoridation (CWF) finds that CWF in New Zealand is safe and effective. The new review, Fluoridation: an update on evidence, was published by the New Zealand Prime Minister’s Chief Science Advisor Juliet Gerrard FRSNZ HonFRSC. It examines scientific findings published since the last New Zealand fluoridation review in 2014 – Eason et al (2014). Health effects of water fluoridation: A review of the scientific evidence. It states:

“Royal Society Te Apārangi published a comprehensive review in 2014 looking at the health effects of water fluoridation [Eason et al. 2014]. The review found that there were no adverse effects of fluoride of any significance arising from fluoridation at the levels used in Aotearoa New Zealand. We have considered new research on fluoridation and comprehensive reviews published subsequently, and find that the conclusions of the Royal Society Te Apārangi remain appropriate.”

So, in effect, nothing new there as far as conclusions are concerned. New Zealanders should continue to welcome CWF without any fear of negative effects. But some readers may be interested in the details – specifically the review’s conclusions about the new research which anti-fluoride activists have been promoting of late. Opponents of CWF have in the last year or so almost exclusively concentrated their campaigns on claimed harmful neurodevelopmental and cognitive impacts. The review considers this in a section “Could fluoride have possible neurodevelopmental and cognitive health effects?” and concludes:

“Recent studies continue to show that at very high levels and with chronic exposure, fluoride could potentially have negative neurodevelopmental and cognitive impacts. However, this is not a concern at levels used in fluoridation of water supplies in Aotearoa New Zealand.”

In particular, the new review considered the studies opponents of CWF claim show harmful effects at the water fluoride concentrations used in CWF. It found problems with these studies and states:

“The conclusion reached by Royal Society Te Apārangi remains appropriate. While there is some evidence that high fluoride concentrations may have an adverse effect on developing brains, there is no convincing evidence of neurological effects at fluoride concentrations achieved by fluoridation of water supplies in Aotearoa New Zealand.”

The new review could be better

Of course, the review is written for policymakers and politicians who want the conclusions but don’t want to see the detailed evidence. They will have confidence that behind the scenes proper scientific scrutiny was made of the studies discussed. But, as a scientist, I would have liked to see more details about that scrutiny. For example, a lot more could be said about the deficiencies of the Canadian study (Green et al., 2019) than:

“There was significant and valid criticism of aspects of the study by many subject-matter experts when it was released (see for example, ‘expert reaction to study looking at maternal exposure to fluoride and IQ in children’). The study used sub-group analysis to find an association that is not explained in the paper (i.e. why were only boys affected and why verbal IQ was not impacted), the effect appeared to be driven by the minority of participants that had much higher fluoride exposures (i.e. higher than those in Aotearoa New Zealand).”

I find this statement in the review a bit misleading:

“The results found in the study undertaken in Canada [56] are also in contrast to those found in the study undertaken in Aotearoa New Zealand [57], which has the advantage of more accurately reflecting local contextual factors.”

It refers to the Green et al., (2019) and Broadbent et al (2015) studies claiming their results are contradictory. But in terms of their comparison of IQ in fluoridated and unfluoridated areas this table shows their findings were exactly the same – absolutely no difference. (Till et al 2020 used essentially the same Canadian data) I think this comparison should have been made clear in the review because it is important but is most often overlooked because opponents of fluoridation, and the study’s authors,  never consider it. They remain silent about the facts in this table. This is hypocritical considering the attempts anti-fluoridation critics made to discredit the same finding reported by Broadbent et al (2015) when their paper was published.

Fluoridation opponents have instead concentrated on the relationships between maternal urinary fluoride and child IQ outcomes reported by Green et al (2019). However, all those relationships were extremely weak (explaining only a few per cent of the variation) or statistically non-significant.

The bias of the authors of the Green et al (2019) and Till et al (2020) studies is evident not only in their complete absence of discussion of their own results showing no difference between fluoridated and unfluoridated areas. It is also shown by the fact neither Green et al (2019) or Till et al (2020) referred to the findings of Broadbent et al (2015) or include that paper in their discussion or reference list. (Contrast this with the fact Green et al 2019 included four papers published in the journal Fluoride, known for its anti-fluoridation bias and poor quality).

These omissions are serious as Broadbent et al (2015) is the only other study of IQ in areas including CWF. This defect in the papers appears not to have been picked up by the publishing journals’ referees – which brings me to question the quality of the peer review used for these papers.

We really need to have a more extensive critique of these studies with proper consideration of the methodologies used (e.g. measurement of urinary fluoride and cognitive factors), the statistical relevance of the reported relationships and the quality of their literature reviews and discussions.

A timely, authoritative and useful review

This new review is timely. The NZ Parliament will soon pass legislation removing the current local body control of regional fluoridation decisions over to the Director-General of Health. Anti-fluoride activists will actively campaign against this and will be promoting misinformation about the recent research. The new review provides lawmakers and the media with up to date scientific information, presented in a popular format, which will counter the anti-fluoridation campaigners.

The backing of the office of the New Zealand Prime Minister’s Chief Science Advisor provides scientific authority. As do the 12 reputable scientists who provided peer reviews of the document.

The more science-savvy members of the public who want to see evidence rather than simply rely on recommendations will also find the review and its bibliography useful.

At this stage, it is not clear how anti-fluoride organisations will attempt to discredit the new review and its findings. In 2014 they worked hard to discredit the NZ Fluoridation Review prepared by the Royal Society of New Zealand and the Office of the Prime Minister’s Chief Science Advisor (Health effects of water fluoridation: A review of the scientific evidence.) They prepared their own critique (promoted as a critique by “international scientists “but actually written by, and “peer-reviewed” by, the usual small group of anti-fluoride scientists and activists) –  with their report Scientific and Critical Analysis of the 2014 New Zealand Fluoridation Report. I critiqued and analysed the report in NZ Community Water Fluoridation is Safe and Effective: A critique of Fluoride Free NZ’s criticisms of the NZ Fluoridation Review which can be downloaded as a pdf.

Many opponents of CWF may be distracted by other things like the Covid19 vaccination issue at the moment. However, the anti-fluoridation campaign has big financial backers locally and internationally so it is likely they will come up with something a lot more effective than the recent attempt by Fluoride Free NZ to pretend that the new review effectively supports their claims.

I look forward to analysing any substantial critique they can make of the updated NMZ Fluoridation review.

A meme promoted by Fluoride Free NZ seeks to pretend the new fluoridation review supports their claims. It doesn’t.

Similar articles

May ’21 – NZ blogs sitemeter ranking

I notice a few regulars no longer allow public access to the site counters. This may happen accidentally when the blog format is altered. If your blog is unexpectedly missing or the numbers seem very low please check this out. After correcting send me the URL for your site meter and I can correct the information in the database.

Similarly, if your blog data in this list seems out of whack, please check your site meter. Usually, the problem is that for some reason your site meter is no longer working.

Sitemeter is no longer working so the total number of NZ blogs in this list has been drastically reduced. I recommend anyone with Sitemeter consider transferring to one of the other meters. See  NZ Blog Rankings FAQ.

This list is compiled automatically from the data in the various site meters used. If you feel the data in this list is wrong could you check to make sure the problem is not with your own site meter? I am of course happy to correct any mistakes that occur in the automatic transfer of data to this list but cannot be responsible for the site meters themselves. They do play up.

Every month I get queries from people wanting their own blog included. I encourage and am happy to respond to queries but have prepared a list of frequently asked questions (FAQs) people can check out. Have a look at NZ Blog Rankings FAQ. This is particularly helpful to those wondering how to set up sitemeters. Please note, the system is automatic and relies on blogs having sitemeters which allow public access to the stats.

Here are the rankings of New Zealand blogs with publicly available statistics for May 2021. Ranking is by visit numbers. I have listed the blogs in the table below, together with monthly visits and page view numbers. Meanwhile, I am still keen to hear of any other blogs with publicly available sitemeter or visitor stats that I have missed. Contact me if you know of any or wish help adding publicly available stats to your bog.

You can see data for previous months at Blog Ranks

Subscribe to NZ Blog Rankings Subscribe to NZ blog rankings by Email Find out how to get Subscription & email updates

Rank Blog Visits/month Page Views/month

1

The Daily Blog

70934

315974

2

Liturgy

22578

28401

3

13th Floor

21991

25681

4

Tikorangi: The Jury Garden

15334

17081

5

SciBlogs

12706

22756

6

Bill Bennett

10239

10996

7

Creative Maths

7791

9283

8

Homepaddock

7344

8001

9

Sacraparental

6953

8017

10

Free range statistics

6719

9426

11

Cycling in Christchurch

6381

7319

12

Music of sound

4245

5492

13

Lost in silver fern

4216

6325

14

Offsetting behaviour

3408

3963

15

Nom Nom Panda

3118

3330

16

Woodleigh Nursery

3116

5100

17

Jontynz

2267

2761

18

The Meaning of Trees

2151

3372

19

No Minister

1526

1757

20

Fields of Blood

1481

1702

21

Sarah the Gardener

1364

1769

22

Talking Auckland

1356

1579

23

Anglican down under

1304

1589

24

The Global Couple

1182

1327

25

Reading the maps

1134

1542

26

The Woolshed Wargamer

1072

1801

27

Open Parachute

964

1164

28

A communist at large

924

1135

29

Muffin-Mum

917

992

30

TVHE

779

870

31

Hot Topic

692

781

32

Rodney’s Aviation Ramblings

669

785

33

Economics New Zealand

554

609

34

Pdubyah – a life just as ordinary

521

568

35

Off the couch

472

575

36

Fun with Allergy Kids

420

561

37

Vomkrieg

390

510

38

Home education Foundation

389

476

39

Aughts and Oughtisms

363

520

40

Kiwi Cakes

352

390

41

Quote Unquote

319

356

42

AmeriNZ

296

547

43

Tales from a Caffeinated Weka

292

305

44

Stratford Aerodrome

285

345

45

Communication, Church, Society

262

412

46

Climate Justice Taranaki

253

369

47

Perissodactyla

233

283

48

Mrs Cake

205

273

49

Sparrowhawk/Karearea

199

266

50

New Zealand Conservative

193

197

51

Cambridge NZ

189

213

52

Creative Voice#

185

342

53

Social Media & the 2014 Election

154

180

54

Eye on the ICR

150

154

55

Save our Schools NZ

148

159

56

Tauranga Blog

143

167

56

AnneKcam

143

187

58

Media Sport and Other Rantings

141

141

59

My thinks

133

167

60

Anne Free Spirit

127

193

61

The Catalyst

111

144

62

Mountains of Our Minds#

100

133

63

goNZo Freakpower Brains Trust

98

99

64

Room 5 @ Melville Intermediate School

95

119

65

Room One @ Auroa School

87

129

66

Right Reason

83

83

67

Aotearoa: A wider perspective

79

82

67

Undeniably Atheist

79

82

69

Glennis’s Blog Page#

78

107

70

Ideologically impure

63

73

71

Put ’em all on an island

61

68

72

John Macilree’s Weblog#

49

53

73

Get Out Gertrude!

48

175

74

Unity Blog

44

55

75

Exile in New zealand

39

40

75

Quietly in the backgroud

39

44

77

Samuel Dennis

38

42

78

Nelsonian’s life

35

40

79

Wellington Chic

33

33

80

Wokarella

32

38

81

MartinIsti Blog

30

31

82

bread and pomegranates

27

34

83

Dad4justice

25

28

83

Family integrity

25

25

83

James McKerrow – Surveyor 1834-1919#

25

26

86

Keeping Stock

23

23

87

ElephaNZa

20

23

88

Glenview 9

18

24

89

Software development and stuff

16

17

89

University of Otago, Law Library Blog

16

19

91

kiwiincanberra

15

15

91

Cut your hair

15

17

93

Journey to a mini me

14

14

94

Room 24, 2012

13

13

94

The Official Ebenezer Teichelmann Blog#

13

20

96

John Macilree’s Blog

12

14

96

Look, Think, Make

12

12

98

kiwi simplexity

11

13

98

Chris Jillet – Mountaineer#

11

14

100

The Well read Kitty

10

10

100

New Zealand female Firefighter calendar

10

10

102

MandM

9

9

102

Four seasons in one

9

9

102

Taradale Blog#

9

10

105

Carolyn’s blog

8

10

105

Warrington Taylor#

8

8

107

ah! New Year’s Resolution

7

7

107

SmallTorque

7

11

109

Utopia – you are standing in it

5

5

110

Helen Heath

4

4

111

New Zealand Indian Fine Arts Society

3

5

111

Socialist Aotearoa

3

3

113

In the back of the net

1

1

113

High voltage learning during the Christchurch earthquakes

1

1

113

The Little Waaagh! That Could

1

1

113

Einstein Music Journal

1

1

Fluoridation contribution to heavy metals in drinking water is too low to measure

Anti-fluoride activists claims of fluoridation chemicals being laced with toxic metals just do not stand up to scrutiny

Anti-fluoridation activists claim fluoridation adds toxic heavy metals to drinking water because the fluoridation chemicals are “waste products” from industry (the phosphate fertiliser industry). Despite the fact that published research shows this not true.

The activists rarely give evidence for their claims but when they do they cite chemical data from certificates of compliance supplied to local bodies by the fluoridation chemical providers. But these activists simply have no concept of what these figures mean and always ignore the huge dilution involved in water treatment.

Example of continually tweeted scaremongering misinformation from the Fluoride Action Network’s press officer.

Anti-fluoride people particularly go on about arsenic yet a 2015 Canadian study showed that the difference in arsenic levels from unfluoridated and fluoridated water treatment plants was infinitesimal. That study is:

Peterson, E., Shapiro, H., Li, Y., Minnery, J. G., & Copes, R. (2015). Arsenic from community water fluoridation: quantifying the effect. Journal of Water and Health.

The data shows that even after treatment the concentration of arsenic due to natural sources is about 0.44 ppb. Fluoridation added a mere 0.07 ppb to this! (ppb = parts per billion = micrograms/litre = μg/L).

See Another defeat for anti-fluoridation claims about arsenic for a discussion of this paper.

The authors point out that all the drinking water systems in their study were compliant with the Canadian drinking water guideline for arsenic of 10 μg/L (10 ppb [parts per billion] – the same as in New Zealand) and the estimated amount attributable to fluoridation from this study is less than 1% of this guideline. Their results were also consistent with other published estimates of the likely contribution of fluoridation chemicals to arsenic in drinking water.

The fluoridation chemicals used in New Zealand have lower levels of impurities than those used in North America so the resulting contamination of drinking water is even lower than in Canada.

Here I look at the heavy metals contaminants in our drinking water and the effect of fluoridation on those levels

What are the concentrations of contaminants in our tap water?

They are very low – in fact, they are regulated to be very low. The regulations set maximum allowable levels (MAV) and providers must keep their contaminant below these MAV levels.

The figure below uses data taken from reports for the Hamilton City Council Water Supply Annual Compliance Report 2018/2019. I have converted the data from units of g/m3 to parts per billion – ppb. I have used data from  a certificate of compliance for the hydrofluorosilicic acid (HFA) supplied to the Hamilton City Council in 2015 (referred to in my article Chemophobic scaremongering: Much ado about absolutely nothing)

I have made this figure tall in an attempt to show the calculated contribution of contaminants concentrations from the fluoride treatment (red) alongside the actual measured levels in the tap water (green). The Y-axis is different for Barium and Aluminium because the concentrations are much higher. Click on the image to see a larger version of the figure

Here are some relevant points about this data:

1: Lead is not included because the amount is below the detection limit. The measured levels of the other contaminants of interest (green) are very low – well below the MAV values.

Waikato River water contains relatively high levels of arsenic – higher than MAV recommendations. But water treatment reduces the levels to well below the MAV level (and in some samples the levels are below the detection limit).

2: The calculated levels for contaminants due to added fluoridation chemicals (HFA – hydrofluorosilicic acid) are extremely low. In fact, in all cases, they are well below the levels that could be detected by the analytical methods used – in most cases far less than 1% of the detectable levels.

This means that the final concentration in drinking water of heavy metals added with the fluoridation chemicals is far too low to even be detected by the sensitive chemical analytical methods used. It is simply misleading for anti-fluoride activists to rave on about the contaminant levels in the concentrated chemicals without taking into account the huge dilution involved.

3: The figure below illustrates that the fluoridation treatment makes only a minuscule (undetectable) contribution of contaminant elements to the tap water.  Well under 1% of the contaminant contribution coming from the source water itself.

Conclusion

Fluoridation chemicals add such a minuscule amount of heavy metals to drinking water that their contribution cannot be detected. The amounts are below the detection limit of the analytical methods used.

The claims of anti-fluoride activists are emotional rather than factual. It is meaningless to publish images of compliance certificates. When they cite chemical data for the fluoridation chemicals used they simply have no concept of what the figures mean and completely ignore the high dilution factor involved in treating drinking water.

Similar articles

April ’21 – NZ blogs sitemeter ranking


Image credit:
Blog Writing For Business NZ

I notice a few regulars no longer allow public access to the site counters. This may happen accidentally when the blog format is altered. If your blog is unexpectedly missing or the numbers seem very low please check this out. After correcting send me the URL for your site meter and I can correct the information in the database.

Similarly, if your blog data in this list seems out of whack, please check your site meter. Usually, the problem is that for some reason your site meter is no longer working.

Sitemeter is no longer working so the total number of NZ blogs in this list has been drastically reduced. I recommend anyone with Sitemeter consider transferring to one of the other meters. See  NZ Blog Rankings FAQ.

This list is compiled automatically from the data in the various site meters used. If you feel the data in this list is wrong could you check to make sure the problem is not with your own site meter? I am of course happy to correct any mistakes that occur in the automatic transfer of data to this list but cannot be responsible for the site meters themselves. They do play up.

Every month I get queries from people wanting their own blog included. I encourage and am happy to respond to queries but have prepared a list of frequently asked questions (FAQs) people can check out. Have a look at NZ Blog Rankings FAQ. This is particularly helpful to those wondering how to set up sitemeters. Please note, the system is automatic and relies on blogs having sitemeters which allow public access to the stats.

Here are the rankings of New Zealand blogs with publicly available statistics for April 2021. Ranking is by visit numbers. I have listed the blogs in the table below, together with monthly visits and page view numbers. Meanwhile, I am still keen to hear of any other blogs with publicly available sitemeter or visitor stats that I have missed. Contact me if you know of any or wish help adding publicly available stats to your bog.

You can see data for previous months at Blog Ranks

Subscribe to NZ Blog Rankings Subscribe to NZ blog rankings by Email Find out how to get Subscription & email updates

Rank Blog Visits/month Page Views/month

1

The Daily Blog

62558

267659

2

Liturgy

34006

40649

3

13th Floor

21768

25129

4

Tikorangi: The Jury Garden

15043

16766

5

Sacraparental

11595

13116

6

Bill Bennett

9320

9924

7

Cycling in Christchurch

8037

9059

8

Creative Maths

7790

9130

9

SciBlogs

7520

17274

10

Homepaddock

7406

8122

11

Free range statistics

6924

9312

12

Music of sound

4531

5942

13

Lost in silver fern

4029

6089

14

Offsetting behaviour

3726

4252

15

Nom Nom Panda

3437

3702

16

Woodleigh Nursery

2575

4645

17

Jontynz

2505

2888

18

The Meaning of Trees

2151

3372

19

Talking Auckland

1411

1578

20

No Minister

1328

1574

21

The Global Couple

1267

1447

22

Fields of Blood

1202

1387

23

Anglican down under

1197

1535

24

The Woolshed Wargamer

1164

2079

25

Economics New Zealand

1143

1165

26

Open Parachute

1077

1324

27

Reading the maps

997

1278

28

A communist at large

967

1213

29

Sarah the Gardener

929

1230

30

Muffin-Mum

889

937

31

Off the couch

740

917

32

Hot Topic

677

866

33

Rodney’s Aviation Ramblings

594

749

34

TVHE

572

649

35

Pdubyah – a life just as ordinary

470

513

36

Home education Foundation

448

526

37

Vomkrieg

382

495

38

Aughts and Oughtisms

367

468

39

Stratford Aerodrome

359

498

40

Climate Justice Taranaki

346

432

41

Kiwi Cakes

325

378

42

Fun with Allergy Kids

306

425

43

AmeriNZ

301

495

44

Communication, Church, Society

277

330

45

Tales from a Caffeinated Weka

264

271

46

Quote Unquote

263

285

47

Perissodactyla

242

267

48

Cambridge NZ

241

263

49

Mrs Cake

214

271

50

Sparrowhawk/Karearea

195

239

51

New Zealand Conservative

175

195

52

Media Sport and Other Rantings

156

159

53

Creative Voice#

144

275

54

Social Media & the 2014 Election

125

150

55

The Catalyst

121

150

56

AnneKcam

112

141

57

Mountains of Our Minds#

111

152

58

Tauranga Blog

104

107

59

Save our Schools NZ

101

105

60

Eye on the ICR

100

122

61

Ideologically impure

89

111

62

Room One @ Auroa School

85

117

63

Room 5 @ Melville Intermediate School

78

92

64

Right Reason

76

76

65

Unity Blog

73

102

65

Undeniably Atheist

73

83

67

My thinks

64

68

67

Glennis’s Blog Page#

64

75

69

Aotearoa: A wider perspective

62

66

70

Exile in New zealand

60

81

71

John Macilree’s Weblog#

58

64

72

Put ’em all on an island

51

58

73

goNZo Freakpower Brains Trust

50

51

73

Anne Free Spirit

50

74

75

Quietly in the backgroud

44

47

76

Family integrity

39

39

76

Wokarella

39

56

78

Glenview 9

30

30

79

ElephaNZa

29

31

80

Wellington Chic

28

28

81

Software development and stuff

24

25

82

Keeping Stock

22

22

82

University of Otago, Law Library Blog

22

32

84

James McKerrow – Surveyor 1834-1919#

20

22

85

MartinIsti Blog

19

21

85

Nelsonian’s life

19

20

87

Dad4justice

16

16

88

John Macilree’s Blog

15

15

88

Get Out Gertrude!

15

21

88

kiwiincanberra

15

15

88

The Official Ebenezer Teichelmann Blog#

15

15

92

kiwi simplexity

14

14

93

Look, Think, Make

12

12

94

Cut your hair

11

11

94

Warrington Taylor#

11

11

96

Carolyn’s blog

10

11

96

Samuel Dennis

10

10

96

bread and pomegranates

10

17

96

Chris Jillet – Mountaineer#

10

10

100

Helen Heath

9

9

100

Four seasons in one

9

9

102

MandM

8

8

102

Journey to a mini me

8

8

104

The Well read Kitty

7

8

104

New Zealand female Firefighter calendar

7

7

104

Room 24, 2012

7

7

107

ah! New Year’s Resolution

6

6

108

Taradale Blog#

5

5

109

New Zealand Indian Fine Arts Society

4

4

109

Socialist Aotearoa

4

4

111

High voltage learning during the Christchurch earthquakes

3

3

112

SmallTorque

2

2

112

Utopia – you are standing in it

2

3

114

Bob McKerrow – Wayfarer

1

1

114

The Little Waaagh! That Could

1

1

114

Misses Mac

1

1

Hip fractures in the elderly and fluoride – contradictory evidence

Room for cherry-picking to confirm a bias. Separate Swedish studies report that fluoride can either prevent or promote the risk of hip fracture in the elderly. Image credit: Are hip fracture patients treated quickly enough?

Anti-fluoride activists are promoting a recent study linking fluoride intake and bone fractures. No surprise there. But they are cherry-picking a single study to support their agenda and scientifically literate people should see the wider picture and not ignore other studies which, on the whole,  convey a different story. This issue illustrates problems with epidemiological studies producing variable results and shows why people should avoid cherry-picking and look at the full range of studies in a field.

Here I consider just two studies on fluoride intake and bone fracture which produced different conclusions. Both studies involved people from Sweden where the natural fluoride levels in drinking water vary across the country.

Drinking water fluoride may protect against hip fractures

First a study from 2013:

Näsman, P., Ekstrand, J., Granath, F., Ekbom, A., & Fored, C. M. (2013). Estimated drinking water fluoride exposure and risk of hip fracture: A cohort study. Journal of Dental Research, 92(11), 1029–1034.

The main findings are illustrated in the figure showing the calculated Hazard Ratios for people of different ages living in areas of Sweden with “very low” (less than 0.3 mg/L), “low” (0.3 – 0.69 mg/L), “medium” (0.7 -1.49 mg/L) or “High” (greater than 1.5 mg/L) fluoride levels in the drinking water. The Hazard Ratio in the figure below is a measure of the number of hip fractures at these levels compared with the number of hip fractures at “Very low” fluoride concentration. The bars represent the 95% confidence intervals. The Hazard Ratios for the “very low” group are 1.0 and Hazard Ratios statistically significantly different to 1 (no effect) are coloured red.

Considering all people there is no statistically significant increase in the number of hip fractures for any level of water fluoride concentration compared with the “very low” levels. The number of hip fractures experienced by people in the two lower age groups (less than 70 years and 70 – 80 years) was significantly lower at higher water fluoride concentrations than at the “very low” concentrations. The authors say:

this “suggests a protective effect of fluoride among the younger (age younger than 80 years): however, the majority of fractures occurred above the age of 80 years (median age at time of fracture, 82.0).”

So a study suggested that the fluoride in Swedish drinking water does not encourage bone fractures and may actually protect against them in the lower age groups.

Fluoride may encourage hip fractures

Now a study from 2021 – the one anti-fluoride activists are promoting (for obvious reasons):

Helte, E., Vargas, C. D., Kippler, M., Wolk, A., Michaëlsson, K., & Åkesson, A. (2021). Fluoride in Drinking Water , Diet , and Urine in Relation to Bone Mineral Density and Fracture Incidence in Postmenopausal Women. Environmental Health Perspectives, 129(April).

Unlike Näsman et al (2013) which used drinking water fluoride concentrations as a measure of fluoride exposure, Helte et al (2021) used urinary fluoride and estimated dietary fluoride intake as measures of fluoride exposure. The Hazard Ratios were calculated from the number of hip fractures in the Tertile 2 groups (0.88 – 1.30 mg/g urinary fluoride or 1.74 – 2.41 mg/day dietary fluoride intake) and Tertile 3 groups (1.30 – 116.51 mg/g urinary fluoride or 2.41 – 11.16 mg/day dietary fluoride intake) compared with hip fractures in the tertile 1 groups (0.14 – 0.88 mg/g urinary fluoride or 0.26 – 1.74 mg/day dietary fluoride intake).

Note: The urinary fluoride units of mg/g represent mg of urinary F/g urinary creatinine. Creatinine levels were used to correct the spot values for dilution.

The Hazard Ratios that statistically significantly different to 1 (no effect) are coloured red in the figure below.

A bit complicated I know, but what the figure shows is no statistically significant increase in hip fracture numbers for the tertile 2 groups compared with the lower F intake tertile one group. But a significant increase in fracture numbers for the tertile 3 groups except for the women exposed to constant water fluoride concentrations since 1982 in the dietary F group.

Hertle et al (2021) also considered other types of fracture. There were no statistically significant increases in fractures in the upper tertiles for either the “all fractures” or “major osteoporotic fractures” classes.

So, a bit of a mixed bag but this paper is currently being promoted by anti-fluoride activists as evidence of a harmful result from community water fluoridation (CWF).

Critically assessing the evidence for bone fractures

It is easy to see why supporters of CWF may cite Näsman et al (2013) as evidence for lack of harm and opponents may cite Helte et al (2021) as evidence of harm from CWF. But neither approach is really scientific. The methodological differences and choice of factors considered can easily explain variable results. One should critically and rationally assess both of these papers, together with the many other papers reporting similar studies, before coming to any conclusion.

On balance, the published studies probably support the findings of Näsman et al (2013) and not Helte et al (2021). In fact, a systematic review and meta-analysis published in 2015 concluded that chronic exposure to fluoride in drinking water was not associated with a significant increase in hip fracture risk. The citation for this review is:

Yin, X.-H., Huang, G.-L., Lin, D.-R., Wan, C.-C., Wang, Y.-D., Song, J.-K., & Xu, P. (2015). Exposure to Fluoride in Drinking Water and Hip Fracture Risk: A Meta-Analysis of Observational Studies. PLOS ONE, 10(5), e0126488. 

It’s worth reproducing one of the figures from that review because it illustrates how epidemiological studies may, individually, support a claim of harm but when considered as a whole these studies do not support the claim. The figure below shows the range of Hazard Ratios obtained by a number of studies.

The lesson here is to be very careful of claims made on the basis of single cherry-picked studies. Especially when those making the claim have a bias they wish to confirm. Every claim should be critically and rationally considered using all the available studies.

Similar articles

 

March ’21 – NZ blogs sitemeter ranking

Image credit: What is the best way to get free traffic to my blog?

I notice a few regulars no longer allow public access to the site counters. This may happen accidentally when the blog format is altered. If your blog is unexpectedly missing or the numbers seem very low please check this out. After correcting send me the URL for your site meter and I can correct the information in the database.

Similarly, if your blog data in this list seems out of whack, please check your site meter. Usually, the problem is that for some reason your site meter is no longer working.

Sitemeter is no longer working so the total number of NZ blogs in this list has been drastically reduced. I recommend anyone with Sitemeter consider transferring to one of the other meters. See  NZ Blog Rankings FAQ.

This list is compiled automatically from the data in the various site meters used. If you feel the data in this list is wrong could you check to make sure the problem is not with your own site meter? I am of course happy to correct any mistakes that occur in the automatic transfer of data to this list but cannot be responsible for the site meters themselves. They do play up.

Every month I get queries from people wanting their own blog included. I encourage and am happy to respond to queries but have prepared a list of frequently asked questions (FAQs) people can check out. Have a look at NZ Blog Rankings FAQ. This is particularly helpful to those wondering how to set up sitemeters. Please note, the system is automatic and relies on blogs having sitemeters which allow public access to the stats.

Here are the rankings of New Zealand blogs with publicly available statistics for March 2021. Ranking is by visit numbers. I have listed the blogs in the table below, together with monthly visits and page view numbers. Meanwhile, I am still keen to hear of any other blogs with publicly available sitemeter or visitor stats that I have missed. Contact me if you know of any or wish help adding publicly available stats to your bog.

You can see data for previous months at Blog Ranks

Subscribe to NZ Blog Rankings Subscribe to NZ blog rankings by Email Find out how to get Subscription & email updates

Rank Blog Visits/month Page Views/month
1The Daily Blog61900283680
2Liturgy3388942005
313th Floor2393226897
4Sacraparental1700519667
5Tikorangi: The Jury Garden1543417167
6Cycling in Christchurch1446715511
7Creative Maths923710967
8Bill Bennett85399047
9Homepaddock82689153
10Free range statistics762610802
11SciBlogs554314889
12Music of sound49946768
13Lost in silver fern40516259
14Offsetting behaviour40034481
15Woodleigh Nursery30285245
16Nom Nom Panda28663064
17Jontynz25093161
18The Meaning of Trees17242751
19Anglican down under16852028
20Talking Auckland14381605
21Open Parachute14161797
22The Global Couple13881614
23Fields of Blood13541582
24The Woolshed Wargamer13332368
25Sarah the Gardener13241745
26No Minister12301421
27Reading the maps11161539
28A communist at large9201052
29Muffin-Mum883915
30Hot Topic8421087
31Off the couch721880
32Rodney’s Aviation Ramblings680844
33TVHE619736
34Pdubyah – a life just as ordinary591635
35Look, Think, Make579648
36Vomkrieg566674
37Economics New Zealand471571
38Kiwi Cakes426466
39Home education Foundation390482
40Stratford Aerodrome382417
41Aughts and Oughtisms374513
42AmeriNZ371536
43Quote Unquote345367
44Fun with Allergy Kids324423
45Media Sport and Other Rantings294300
46Perissodactyla273304
47Climate Justice Taranaki263374
48New Zealand Conservative257269
49Communication, Church, Society251342
50Tales from a Caffeinated Weka249262
51Cambridge NZ235276
52Eye on the ICR179209
53Sparrowhawk/Karearea178215
54Save our Schools NZ164181
55Mrs Cake160221
56Creative Voice#138212
57AnneKcam132169
58Right Reason129129
59The Catalyst122169
60Social Media & the 2014 Election111125
61goNZo Freakpower Brains Trust103104
62Room 5 @ Melville Intermediate School101113
63Keeping Stock9396
64Undeniably Atheist8893
64Mountains of Our Minds#88113
66Ideologically impure8388
67Room One @ Auroa School80104
68John Macilree’s Weblog#7786
69Unity Blog7476
69My thinks7481
71Aotearoa: A wider perspective6977
72Tauranga Blog6570
73Glennis’s Blog Page#58117
74Exile in New zealand5457
75Wokarella5360
76James McKerrow – Surveyor 1834-1919#4549
77Put ’em all on an island4456
78Anne Free Spirit4357
79Wellington Chic3939
80Software development and stuff3839
81Quietly in the backgroud3742
82Glenview 93246
83Dad4justice2830
83Family integrity2828
85Taradale Blog#2526
86Socialist Aotearoa2424
87ElephaNZa2223
88MartinIsti Blog2126
88The Official Ebenezer Teichelmann Blog#2121
90Get Out Gertrude!1919
91University of Otago, Law Library Blog1717
92ah! New Year’s Resolution1515
92Cut your hair1515
94bread and pomegranates1417
94Nelsonian’s life1415
96John Macilree’s Blog1212
96kiwi simplexity1212
96Sharlene says1212
99Journey to a mini me1111
99SmallTorque1112
99Four seasons in one1111
102Chris Jillet – Mountaineer#1010
103Carolyn’s blog911
103The Well read Kitty99
103MandM99
103Room 24, 2012910
107Helen Heath77
108Samuel Dennis66
108Warrington Taylor#66
110New Zealand female Firefighter calendar55
111High voltage learning during the Christchurch earthquakes44
111kiwiincanberra44
111The Little Waaagh! That Could44
114Blogger at Large33
114Utopia – you are standing in it33
116New Zealand Indian Fine Arts Society22
117Misses Mac11

sasas

An open letter to Paul Connet and the anti-fluoride movement

Paul Connett and Vyvyan Howard have, through the local Fluoride Free New Zealand activist group, published an open letter addressed to NZ scientists and educators (see An Open Letter To NZ Scientists And Educators). It is strange to encourage scientific exchanges through press releases but if they are seriously interested in an exchange of informed scientific opinion on the research they mention I am all for it.

In fact, I renew my offer to Paul Connett for a new exchange on the new relevant research along the lines of the highly successful scientific exchange we had in 2013/2014 summarised in Conett & Perrott (2014) The Fluoride Debate.

Connett and Howard say they felt “let down” by the reception they received in their 2018 visit. But they should realise this sort of ridicule is inevitable when a supposedly scientific message is promoted by activist fringe groups with known funding by big business (in this case the “natural”/alternative health industry). The science should be treated more respectably and discussed in a proper scientific forum or via a proper scientific exchange rather than political style activist meetings.

It is this sort of respectable, informed and open scientific exchange I am offering to Paul Connett and Vyvyan Hoard.

Connett and Howard argue that there has recently been  “a dramatic change in the quality of these [fluoride] studies.” I agree that new research occurs all the time and there is plenty of scope upgrading of the scientific exchange we had in 2013/2014 to cover that new research. Consideration of the new research requires the objective, critical and intelligent consideration scientists are well used to and this is not helped by activist propaganda meetings. So I encourage Connett and Howard to accept my offer. after all, if they are confident in their own analysis of this research what do they have to lose?

Inaccuracies in “open letter”

One can see an “Open letter” as displaying a willingness to enter into a proper scientific exchange. However, Connett and Vivyan’s open letter includes inaccuracies and misinformation on the new research which simply demonstrates that a one-sided presentation cannot present the research findings properly.

For example, they misrepresent the 2014 New Zealand fluoridation review of Eason et al (2014). Health effects of water fluoridation: A review of the scientific evidence. Even to the extent of mistaking the authors (not Gluckman & Skegg as they claim) and misrepresenting the small mistake made in the summary which was later corrected. That attitude does not bode well for the proper consideration of the research.

Connett and Howard concentrate on new research relating child IQ to fluoride intake but they ignore completely the fact that all the research comparing IQ in fluoridated and unfluoridated areas show absolutely no effect. I have summarised the results for the three papers involve in this table.

Instead, they concentrated on a few extremely weak relationships reported in a few papers. But even here they get this wrong – for example, they say there is “a loss of about 4 IQ points in offspring for a range of 1 mg/liter of fluoride in mother’s urine.” The paper they refer to (Green et al 2019) actually found no statistically significant relationship between child IQ and maternal urinary fluoride for all children considered. The relationship Connett and Howard mention was actually for male children (no relationship for female children or for all children) and was very weak. These sort of weak relationships are commonly found in epidemiological research and are usually meaningless. In this case, Connett and Howard have simply cherry-picked one value and misrepresented it as applying to all children.

Both the Green et al (2019) and Till et al (2020) papers Connett and Howard refer to suffer from selecting a few weak statistically significant relationships and ignoring the larger number of non-significant relationships they found for the data they investigated. Connett and Howard also completely ignored the new studies that don’t fit their claims. For example that of Santa-Marina et al (2019). Fluorinated water consumption in pregnancy and neuropsychological development of children at 14 months and 4 years of age. which showed an opposite positive relationship of child IQ with maternal urinary fluoride. Similar they ignored the large Swedish study of Aggeborn & Öhman (2020). The Effects of Fluoride in the Drinking Water showing no effect of fluoride on IQ but positive effects on oral health and employment possibilities in later life.

In conclusion, I reiterate that genuine open scientific exchanges do not take place via press release and activist meetings. However, the fact that Connett and Howard have issued an “Open Letter” could be interpreted as inviting others to participate in a proper exchange. I endorse that concept and offer Connett and Howard space for a free and open exchange on the new research at this blog site.

Similar articles