HomeMy WebLinkAbout7B - Discussion on fluoridation of drinking waterCITYOFBOULDER
WATER RESOURCES ADVISORY BOARD
NON-AGENDA ITEM
MEETING DATE: Sept. 20, 2004
AGENDA TITLE: Staff presentation and WRAB discussion on fluoridation of
drinking water.
PRESENTER/S: Ned Williams
EXECUTIVE SUMMARY:
The issue of fluondahon of dnnkmg water is being reviewed by the Environmental
Advisory Board (EAB) and they aze seekmg input from the WRAB on the issue Included
m this packet item is a collechon of mforrnation mtended to provide background on the
issue as rt has been evaluated by the WRAB and others in the past
Fiscal Impacts:
N/A
Other Impacts:
N/A
Other Board and Commission feedback:
The EAB has previously addressed this issue and is discussing whether to do so agam
(Attachment A) The board is seekmg mput from the WRAB on the issue before
proceedmg wrth any formal achon.
The city of Boulder Attorney's office has evaluated cessation of fluondation achvities
with respect to the ordmance that requires fluondation (Ordinance No. 3515). The results
of that evaluahon are attached (Attachment B)
The crty of Ft Collms has exammed the issue through the use of a Fluonde Techmcal
Studies Group (FTSG). Information about the FTSG and their resultant study are
mcluded (Attachments C and D).
Public feedback:
Public feedback has remazned controversial on the topia Summary Ytunutes from the May
21, 2001 WRAB meehng, when the WRAB previously discussed the issue, address the
controversy surroundmg the topic (Attachment E)
Staff recommendation:
The staff is makmg no recommendation at ttus hme since the topic is presented for
discussion only.
Analysis:
N/A
Matrix of options:
N/A
Attachments:
Attachment A Letter from the EAB requeshng WRAQB mput"
Attachment B: Letter from city of Boulder Attorney's office addressing cessat~on of
fluondation
Attachment C Pnntouts of city of Ft Collms Web pages addressing fluondatron and the
report produced by the FTSG
Attachment D FTSG report
Attachment E. WRAB Summary Mmutes from May 21, 2001 m which the WRAB
considered the issue
I-{ ~~cG~ ~ch-f ,4-
----Onginal Message-----
From: Randali Weiner [mailto:ecolaw@bsuites.com]
Sent: Monday, August 16, 2004 1:31 PM
To: bart@westernresources.org; m~ller@westemresources.org
Cc: Susan Iott; Kathie Joyner; John Putman; Alice Guthrie; Daniel Ziskin
Subject: fluoride issue
Dear Bart:
In 1969, Boulder cihzens voted to add fluoride to the City's water supply by a 52% to 48% ma~onty In two prevtous
elechons, Boulder voters had said "no" to addmg fluonde The ~ssue has conhnued to be conuoven~al dunng the thaty years that
Boulder has been fluondaang its water
More recently, Canada's foremost promoter of fluondahon, the Pres~dent of the Canadian Assoc~ahon of Dental Reseazch,
stated that "for the past 15 years, I had refused to study the rox~cology mfonnauon that ~s readily available to anyone Pouomng our
children was the furthest thmg from my mmd " ABC news suggested a few months ago that the science supportmg the e~cacy of
addmg fluonde to dnnkmg water is "~unk" sc~ence In the past decade, over 60 commumhes m the U S and Canada have discontmued
or re~ected water fluondahon, includmg Spokane, WA, Albany, N Y and Salt Lake C~ty
The Envaonmental Advisory Board (EAB) previously addressed Ih~s issue We have d~scussed whether to do so
agam However, I have been asked to fmd out what your Board's posihon ~s before we take any achon. Does your Board have the
experGse or mclmat~on ro rev~ew the toxiwlogical impltcat~ons of contmumg to add fluonde to Bouldei s water supply~ Could you
check tlus out for us~
Thank you, Bart
Randy Wemer
Cha~r, Env~ronmental Advisory Board
Law Offices of Randall M Weiner, P C
1942 Broadway, Swte 408
Boulder, CO 80302
303-938-3773
303-442-6622-FAX
ecolaw@bswtes com
file://C:~Documents%20and%20Settings\willrl 000\Local%20Sethngs\Temp\GW}00001 HTM 9/10/2004
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CITY OF BOULDER, COLORADO
Otlice of the City vMmev
Atumc~pal Bwldmg
I777 Brcudway
Post Oflice Boe 79I
BouldeG Cobrado SU305
Telephone(303~441-3020
Facs~nule(303)411-33i9
MEMORANDUM
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TO: Mike Weil, Director of Env~ronmental Affairs
FROM Sue Ellen Hamson, Assistant City Attorney ~~ ~-~y ~- `~ ~~ ~ - __
SUBJECT Cessation of Fluondation of Water Pursuant to Ordmance No 3513
DATE May 31, 2001
INTRODUCTION
The City Attorney's office has revtewed Ordmance No 3513, mcludmg the Crty Charter
requtrements for amendmg the ordmance. It is the opmion of this office that the ordmance is
mandatory, and m order for the Crty to cease fluondahon, the ordmance must be repealed by a
vote of the people
NATURE OF THE ORDINANCE
Ordmance No 3513 was passed by a vote of the people m November, 1969 The power
to mihate legislatton is provided for m the State Constituhon, Art. V, Section l, and the City
Charter, Section 37. The wordmg of the ordmance created a mandatory mrtiarive requmng the
fluondahon of City water The operative sentence reads
The Coordmator of pubhc facilihes . is hereby authonzed and dtrected to
provide a means and to proceed with the mtroduchon of the fluonde ion mto
the water supply fumished thts mumcipaltty m such quantihes as aze required
to mamtam throughout the pipe distnbution system a fluoride ion
concentration of approximately one part fluonde to one million parts water
Ordmance No 3513, Secrion 1
There is no language which gives the City any discrehon in the matter The Coordmator is
directed to proceed to mtroduce fluoride mto the water and to mamtam a speafic concentration.
REPEAL OF THE ORDINANCE
The City Charter provides in Sechon 54 that
No ordmance that has been passed by a vote of the people under the
imt~at~ve orhas recerved a favorable vote of the peopleunderthe referendum
shall be repealed except by an ordmance submitted to a vote of the people
This ord~nance was passed pursuant to the imttat~ve power, thus pursuant to Charter Section 43, a
repeal of the ordmance requues Ctty Council to submit the ~ssue to a vote of the people by a
c~tizen referendum In add~tion, cit~zens may, pursuant to Charter Sectton 37, mihate an
ordmance to ehmmate or othenv~se change, fluondat~on.
CONCLUSION
If Public Works, the WRAB, the EAB, or cit~zens w~sh to d~scontmue fluondatmg City water,
C~ty Counc~l must submit a referendum to the people to repeal Ordmance No 3513, or citizens
may proceed on their own wuh an m~t~ative
I~ P\V W 4 m-tlurord Ado
Crty oY Nort C;ollms departments: uhlihes iluonde ~~ ~~~ C Page 1 oY 1
Drinking Water Fluoridation
Overview ~ Technical__Study_Grou~ ~ Re~ort
After almost two years of review, on July 15, 2003, City
Council voted 4-3 to contmue the City's fluoridation
program. The review process mcluded a comprehensive
review of the scientific literature on fluoridation by the
Fluoride Technical Study Group (FTSG), a group convened
by the City and the Health District of Northern Lanmer
County. This process included both technical review and
public comment. The FTSG presented findinqs to the
Larimer County Board of Health and the Water Board who
then made recommendations to City Council. Council
considered the recommendations of the Board of Health, the
Water Board and the Board of the Health District, as well as
comment from the public prior to the ]uly vote
The Current Fluoridation Program
As part of ongomg education about the current Fluondation program and the types of
fluoride products used in fluoridation, the City provides the foilowing information.
The City of Fort Coll~ns Utilities adds Fluoride to its water resulting in fluoride levels in
the range of 0.7 to 1.2 milligrems of fluoride per liter of treated water, with a target
amount of 1.0 mdligram per liter. This fluoridation has been part of the Utilities'
treatment process for over 30 years, and is currently accomplished through the
addition of hydrofluorosilicic acid. If you or members of your household are sensitive
to fluonde or fluondation-related substances, or provide City water to an mfant
younger than sfx months of age, please consult with your physician or other health
expert regarding fluoridation-related precautions you may want to consider.
For additional informat(on, please review the Fluoride Technical Study Group Report
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Fluoride Technical Study Group Report Customer Service
February 3, 2003 • Sta Stop/Change Your
Service
Overview ~ Technical Study Group ~ Report • pavinq Your B~II
This report presents the consensus findings of the Fluoride Technical Study Grouo, • Rates & Fees
which was charged with assessing the risks and benefits of community water Generai Info
fluoridation. The report wdl help nsk managers (the L~nmer County_Board_of Health,
the Water Board and the Fort Colhns City Councd) decide whether to cont~nue, alter • Contact Us
or discontinue dnnking water fluoridation • Saving Enerqv
The execu iv~ summary (PDF) Iists the five most important wnsiderations underlying ' Water Conservation
the report and its findmgs, and then presents the findmgs themselves, which were •_Pro rams & Serwces
developed in four categories~ • On-line Publications
Our Four Utilities
• The effectiveness of drinking water Fluondation in preventing cavities • Electric
• The nsks of fluondation and of cumulatrve exposure from all sources • Stormwater
. The costs and benefits of both addmg and not adding fluoride and
. The potential for increased contaminant levels in drmkmg water due to the use of •~^!astewater
hydrofluorosdiac aad in the fluondation process • Water
Read the report's introduction (PDF), (revised Apnl 9, 2003) to learn more about the
group's process, pnonties, literature review method, weight of evidence approach
with uncertainties, important background information, and more.
The full reoort (revised April 9, 2003), is available in a portable document format
(PDF - 7.05 MB 227 pages) To read a PDF, you will need the free Adobe AsL2k~t
Reader Review the Table of Contents for downloadabie sections of the report.
To receive a copy of the report by mail, e-mad us (Please allow five busmess days,
one copy per request.)
For more information, call 221-6700 or e-mail
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City of Fort Collins departments utihhes techmcal study group
Fluoride Technical Study Group
Ov_erview ~ Technical Study Group ~ Report
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The Techrncal Study Group fncluded nine community members with an interest m • paying Your Bdl
community dnnking water fluoridation and with specific techrncal, medical or
scientific capabilities The group met at least once a month between December 2001 • Rates_& Fees
and December 2002 to: General Info
. expiore information related to the costs and benefits of community dnnkfng-water
Fluondatfon. This includes summarizmg what is known and not known about the
risks and benefits of adding-or not adding-Fluoride to the dnnking water supply.
• develop and present findmgs to the Lanmer County Board of Health and the F_o_rt
Collins Water Board so they can offer mformed recommendations to the Fort
Collins City Council.
On luly 15, 2003, City Council voted 4-3 to contmue the City's Fluoridation progrem
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• Stormwater
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• Water
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A~c~~,~,~~ ~
Table of Contents
Table of Contents
Executive Summary
Introduction
...
...................... ui
.......................1
Finding #1 - The Effectiveness of Drinking Water Fluoridation in Preventing Caries......... 9
H~stoncal Perspective . . . .... . . . . . . . . . . . .9
How Fluonde Works . . . . . . .. . .... . . . . . . .. . . .. 13
Ev~dence of Effectiveness of Commumty Water Fluondat~on . . . ... ... 14
Evidence of the Current Magmtude of Effechveness . . . 16
Studies of the EffecUveness of Commumry Water Fluondat~oa m Adults . . 18
Fluondahon-Ended S~[es m Wh~ch No Canes Increases Were Found. . .. 18
Gaps m Knowledge . . .. .. . . . . . . . 20
FINDINGS The EffecGveness of Dnnkmg Water Fluondahon m Preventmg Canes (Cavit~es) 21
Reference List . . .. . . . . . . . . . . . . . . . . . . 22
Finding #2 - The Risk of Drinking Water Fluoridation.....,
Total Exposure to Fluonde . . .
FINDINGS Total Fluonde Exposure . . . .
Review of Potent~al Adverse Health Effects
Cancer . . .. . .
FINDINGS Cancer. . . . . .
Bone Fractures and Osteoporos~s . . . . . .
FINDINGS Bone Effects. .. .
Skeletal Fluorosis . . . . . .
FINDINGS Skeletal Fluoros~s. . . . .
Dental Enamel Fluorosis . . . .
FINDINGS Dental Fluorosis. . . . .
Thyroid Funct~on . . . . . . .
FINDINGS Thyrmd Function . . . . .
Immune System Effecu . . . . .. . . . . .
FINDINGS Immunological Effects . . . . . . .
Other Potential Health Effects . . . .
FINDINGS Other Health EfFects . . . . . . . .. .
Reference List . . . . . . .. . . . .. . .
........................................... 25
. 25
. . .. 30
. 30
. . 30
. 34
. . 34
- - - 37
. . . . 37
.. 40
. . . 40
. . . . . .44
... . . .... 44
. . . .. .45
- - - - - - - . 45
. . . . . . 46
. . . . 46
.. 48
. . . ... .. 49
Finding #3 - Costs and Benefits, Includmg the Distribution of Costs and Benefits.......... 51
Cost-Effechveness of Commumry Water Fluondat~on ... . . . . . . . . . . . 51
Distnbut~onal Effects of Commumty Water Fluondation . . 55
Effectrveness and Cost-Effectrveness of Other Fluonde Modalmes Relauve to
Commumty WaterFluondation . . . . . . . . 56
FINDINGS Costs and Benefits . . . . . . . 58
Reference List . . .. . . . . . . . . . . . . . . . 59
Finding #4 - The Potential for Increased Contaminant Levels Due to the Use of
Hydrofluorosilicic Acid ............................................................................................................ 61
Background . . . . . . . . . . . . . . 61
Fluoride Sources . . . . . . 61
Fluonde Manufactunng Process . ' . . 61
Methods of Appl~cahon . . . . . . . 61
Table of Contents i
Water Quality . . . . . . . . . . .. . 63
Analyhcal Informahon. . . . . . . . . . 63
Uncertvnhes . . .. . . ... .... .. . .66
FINDINGS The Potent~al for Increased Contacmnate Levels Due to the
Use of Hydrofluoros~lw~c Acid . . . . . . . . . . . . . . .. . 71
Reference List . . . . .. . . . . . . . . . . . . . . . . ... . . . . 72
Appendix A-7 - Fort Collins Fluoride Technical Study Group Tiered Reference List........73
F~rst T~er . . . . . . ... . . 73
Other Lrterature Reviewed . . . . . . . . . . . . . . 74
Matenals Submitted by Members of the Publ~c. . . . . . . . . . . . . . 95
Appendix A-2 - Fluoride Mass Balance Calculations
City of Fort Collins Water Treatment Facility ................ ......................................................101
Appendix 1- Effectiveness of Community Water Ftuoridation
Methodological Approaches of "Tier One" and Other Reviews ... .....................................103
T~er 1 Reviews . . 103
Other Reviews . . . . . . . . 106
Appendix 2- Risks According to "Tier One "Reviews ........................................................109
Inuoduct~on . . . . . .109
Cancer . . . .. 110
Bone Fractures and Other Bone Effects . . . . . . . . . 119
Skeletal Fluorosis 127
Enamel (Dental) Fluoros~s 133
Other Health Effects 144
Appendix 3- Cost Effectiveness Studies ............................................................................. 159
Table 1 Cost-Effechveness Stud~es, U S . . . . . . . . . . 159
Table 2 Cost-Effechveness Studies, Other Countnes . . .. 163
Table 3 Other Delivery Strateg~es for Fluonde . . . .. .. 167
Table 4 Other Strategies for Pnmary Prevenuon of Dental Canes . . .. 170
Econom~c Analys~s of Commumty Water Fluondahon m Fort Collms, Colorado. . ... 172
References . . . . . 174
Appendix 4- The Pote~tial for Increased Contaminant Levels Due to the Use of
Hydrofluorosilicic Acid ...........................................................................................................175
4 1 Matenal Safety Data Sheet Fluonde .. . . . . . . . . . . . . 175
4 2 Fluonde Manufactunng Process, Figures 1 and 2 . . . . . . . . . . . . . 181
4 3 Report Form 1 . . . . . . . . . 183
4 4 NSF Cerhficatwn . . . . . . . . . 184
4 5 Fort Collms Uttl~t~es Drmkmg Water Consumer Confidence Report, 2001 . 188
4 6 Fort Collms Ut~lit~es Dnnkmg Water Quahty Summary, 2001 and 2002 .. .... ..190
4 7 Results for Iron, Copper, Manganese, Zmc, Cadmmm and Nickel, Figures 3- 9 ... . 193
4 8 Arsemc Concentration m Fmished Water .. . . . ... 194
4 9 Peer Rev~ews of the Masters and Coplan Report . . .. . .. 198
4 10 Lead Data Regress~on Analysis . .. . . . . . . . . .. . .225
u Report of the Fort Colhns Techmcal Smdy Group - January 2003
Introduction
In response to quesuons from the publ~c about the nsks, benefits and costs of community dnnkmg water
fluondahon, the C~ty of Fort Colims convened the Fluoride Techmcal Study Group (FTSG) to fulfill ihe
followmg responsibdity
• To explore mformat~on related to the cosu and benefits of commumty dnnkmg-water
fluondaUon,
• To summanze what is known and not known about the nsks and benefits of addmg fluonde;
• To summanze what is known and not known about the r~sks and benefits of not addmg fluonde,
. To develop and present findmgs,
• To base findmgs on the h~gh qual~ty scienh£c and techmcal mfoccnahon,
• To work towazd consensus findtngs whenever possible,
• To clanfy areas of a~eement and of d~sagreement about the ~mphcat~ons of [he mformahon,
• To mtegrate pubLc mput mto the recommendations; and
• To present data, consensus findmgs and areas of disagreement to the Boazd of Health and the
Water Boazd so that these two boazds can offer mformed recommendaGons to the Fort Collms
City Council
The Fluonde Techrucal Study Group (FTSG) mcludes mne commumty members w~th an mterest m the
quest~o~s surroundmg commumty dnnlung water fluondat~on and with spec~fic techntcal, med~cal or
sc~entiFic capabtltt~es The FTSG members are
Ed Carr, DC, MS
Ch~ropractor and Wellness Counselor
Bruce Cooper, MD, MSPH
Medical D~rector
Health Distnct of Northem Lanmer County
Greg Evans, DDS
Ped~atnc Denhst
Gale McGaha M~ller, BS
Water Qual~ty Serv~ces Manager
Fort Colhns Ut~lrties
Ram~ Naddy, PhD
Env~ronmental Tox~colog~st
ENSR Intemahonal
Member of City of Fort Collms
Water Boazd
Kevm Gertig
Cerhfied Colorado Water Works
Operator A
Water Producuon Manager
Fort Collms Utdd~es Water Treatment Plant
Adnenne LeBailly, MD, MPH *
D~rector, Lanmer County
Department of Health and Env~ronment
John Re~f, DVM, MSc (Med)
Professor
Department of Env~ronmental Health
Colorado State Umvers~ry
Frank Vertucc~, PhD, MS
Cemfied Semor Ecolog~st
ENSR Intemahonal
Vice President of the
Lanmer County Board of Health
' Although Dr LeBailly's workload necess~tated that she wdhdraw from the rev~ew process m Summer 2002, she
. was very achve m eazly meehngs and helped estabhsh gmdefines and rev~ew crrter~a She has conhnued to follow
the group's praceedmgs
Introduchon
Process
The Fluonde Techmcal Study Group (FTSG) met monthly as a full group, once each month, between
December 2001 and November 2002 Dunng the report draftmg process m the latter 6alf of 2002, smaller
subseu of FTSG members met frequently to draft vanous sect~ons of th~s document The FTSG met three
times m December of 2002 to reach final consensus on the document In add~t~on, the FTSG held two
public meetmgs m eazly 2002 to mvite mput and advice from the public before begmmng ~u work, and
two in eazly 2003 to present and d~scuss report fmdmgs
Throughout the process, the FTSG encouraged ongomg pubhc mput Of particulu note ~s the fact that at
least one-third of the FTSG members exammed every techmcal s[udy, ~oumal azticle, newspaper aR~cle or
v~deotape subm~tted by members of the publ~c All nme members reviewed those pubhc subtrussions
deemed by any one member to be of s~gmficant sc~ent~fic or techmcal ment, and therefore worthy of
mclusion m the FTSG del~berat~ons The techmcal and scienhfic mfocmahon was assembled, rev~ewed
and distnbuted to the FI'SG by Susan Hewitt of the Health D~stnct of Northem Lanmer County, who also
assisted m editmg and preparing the final draft report
The FTSG also made efforts ro keep the public mformed of the work that was bemg accompl~shed All
FTSG meehngs were open to the publ~c, although no pubLc comment was taken at these meehngs
Summanes of the publ~c meetmgs and the FTSG meehngs were posted on a webstte mamtamed by the
Fort Collms C~ty Ut~hty Deparknent AddR~onally, three sets of the reference matertals used by the FTSG
were ava~lable for rev~ew by members of the publ~c at three locahons m Fort Colhns
Pnorities
In ds earlies[ meetmgs (and aRer publ~c meetmgs that eltcded important topics) the FTSG pnonhzed the
key questions and centered its mquiry on developmg findmgs m response to these pnont~es The FTSG
reviewed the scientific and techmcal I~terature for mformation about seven topics, s~x broad top~cs and
one specific to a smgle d~sease end pomt
• The effectrveness of dnnkmg water fluondahon
• The nsk of dnnkmg water fluondaUOn
• The nsk of cumulahve exposure [o fluoride (over time) from all sources, mcludmg dnnkmg
water,
• The costs and benefits of not fluondahng the dnnkmg water supply, mcludmg assessmg the
d~stnbuhon wsts and benefits (equity)
. The effechveness of altemative methods of deLvenng fluonde
• The effechveness of addressmg fluondahon as a public health issue and the effecuveness of
addressmg fluondauon as an mdividual choice
. The nsk of ~mpacts to thyroid funct~on due to dnnkmg water fluondahon
After generahng its m~hal draft of th~s report, the FTSG has consoUdated its findmgs mto these four
top~cs
1 The effectrveness of drmkmg water fluondation
2 The nsks of dnnkmg water fluondahon and of cumulaUve exposure to fluonde from all sources,
mcludmg dnnlung water, over ume (with spec~fic attenhon to cancer, bone fractures, skeletal
fluorosis, dental fluorosis and thyroid function)
3 The costs and benefits of fluondahng the dnnk~ng water supply, and of not fluondaAng the
dnnkmg water supply, mcludmg assessmg the d~stnbuhon costs and benefiu (eqmty), and
mcludmg the costs and benefits of usmg altemahve methods to dehver fluonde
4 The potenUal for mcreased contammant levels m the dnnkmg water due to We use of
hydrofluorosilicic acid m the fluondahon process ,
Report of the Fort Collms Fluonde Techmcal Study Group - Apn12003
Technical Studv Groua Literature Review Method
From the start, ~t was acknowledged that the pubhshed sc~enhfic l~terature base on communrty water
fluondation was enocmous and that rt was beyond the scope of this group to conduct a systematic review
of thousands of pnmary studies The FTSG elected to use a hered approach to rev~ewmg the exisUng
literature on water fluondahon, turning first to already conducted and pubLshed scientific literature
research rev~ews and comp~lahons Only when a gap m the data became evident or when a spec~fic need
for more mformahon was needed did the group tum to and evaluate pubLshed, peer-rev~ewed pnmary
studies Imt~ally, a half dozen comprehens~ve Lterature reviews were located and shared by the FTSG,
with addihonal studies and compilahons located dunng the process Ultimately, a tiered arrangement of
the literature uhhzed by the FTSG was compiled
• "Tier One" hterature were those by well-known, authontahve and unb~ased nahonal and
mternat~onal pubLc health agenc~es such as the Umted States Pubhc Health Serv~ce, the World
Health Orgamzat~on, the Umted States Centers for D~sease Control and Prevenuon, the Nat~onal
Inshtutes of Health, the Medical Research Council of Great Bntam, and the BnGSh Nauonal
Health Serv~ces Centre for Reviews and D~ssemmahon
• The next her mcluded
• Publ~shed luerature reviews and meta-analyses
• Reports of pnmary studies pubhshed m peerrev~ewed ~oumals that were used to fill data
gaps or when add~twnal explanahon was needed
• Luerature rev~ews conducted by or contracted by mumc~pal, provmcial, or other local
governmental enhues that were used for local decis~on makmg These were pnmanly used to
idenhfy "T~er One" studies and primary l~terature
• Other matenals cons~dered by the FTSG mcluded ed~tonals, commentary and fact sheets, some of
whwh were suppl~ed by members of the public
Concemmg "Tier One" and o[her hterature, each of these studies used d~fferent seazch and review
strateg~es Some used expLcitly stated and highly systemahc methods to evaluate the scienhfic ment of
studies, while others used more impl~cit and more sub~ectrve methods such as relymg on an evaluat~on of
the quahty of the luerature by sub~ect matter experts The tiered reference list ~s provided m Appendix A-
1. Addrtional mformahon on the search and review strateg~es of many of the her one Lterature and other
documents ~s presented m Append~x 1.
Studv Criteria
The FTSG, for the most part, hmited cons~deraaon to scienhfic stud~es of dnnkmg water fluondat~on at
or uound 1 crulhgram per hter (mg/L) or 1 part per mill~on (ppm), because it is the target amount of
fluonde added to the Fort Collms city water supply (range of 0 7- 1 2 mg/L w~th data mdicahng strmgent
control at 1 0 mg/L) In some cases, studies where expenmental an~mals were dosed at a higher level or
human ep~dem~olog~cal or pharmacolog~cal stud~es of populat~ons exposed to h~gher doses of fluonde
were considered by the FTSG to better understand potent~al cumulatrve or dose-dependent effects
Please note the terms part per million (ppm) and m~lligrams per l~ter (mg/L) aze used mterchangeably
throughout th~s report. They aze more or less equrvalent and each temi is used by the Lterature c~ted by
the FTSG In layman's terms 1 ppm or 1 mg/L fluonde represents one "drop" of fluonde m one m~llion
"drops" of water
Weiqht of Evidence Apuroach With Uncertainties
Members of the FTSG used the weight of evidence approach m evaluahng scienhfic stud~es The EPA
defines the we~ght of ev~dence approach as "Considerahons m assessmg the mterpretahon of published
mformat~on about tox~city-qual~ty of teshng methods, size and power of study design, consistency of
results across stud~es, and biological plausibility of exposure-response relat~onships and stat~sucal
Introduct~on
associahons" (http //www epa eov/OCEPAtemis~ Thus, all the sc~ent~fic Irterature on a topic ~s
evaluated, with studies categonzed mro levels of better and lesser studies based on such vanables as
degree of ineasurement accuracy, number of study sub~ecu, how data was collected, control of potenhal
confoundmg factors and so on. The best studies get the most weight and the poorer studies less weight or
disquahficat~on if a certam standard is not met Particulaz attent~on ~s grven when mulhple studies, by
different reseazchers, usmg dtfferent methods, m vaned populahon groups reach similaz conclusions.
Such findmgs generally corroborate hypotheses and aze particularly useful when lookmg for subtle health
changes due to the large numbers of sub~ects measured The converse ~s also important, if mulhple stud~es
show contrad~ctory pos~hve or negahve effects then no overall effect is d~scemable and hypotheses may
be refuted before a lmk is made to potenhal hann or benefit The FTSG acknowledged uncertamhes aze
mherent when sc~enhfic lrterature is evaluated
Some members advocated for the precauhonary prmc~ple, defined by the EPA as"When mfortnahon
about potent~al nsks is mcomplete, basmg dec~s~ons about the best ways to manage or reduce nsks on a
preference for avoidmg unnecessary health r~sks mstead of on unnecessary ewnomic expendrtures"
(http //www epa eov/OCEPAterms~ In other words, to ass~st the nsk managers, the weight of ev~dence ~s
cons~dered as well as the magmtude of the calazruty that a worst-case scenano may produce if the
evidence ~s flawed or maccurate
The FTSG endeavored to create a balanced report for use by decision-makers that took mto account the
most current and best available analysis of the weight of the scienafic ev~dence on the nsks and benefits
of commumty water fluondahon The ~oup also acknowledged that there aze gaps m the knowledge and
uncertvnties aze mherent m the ab~Lty to fully understand what may be subtle, yet unportant health effects
that aze yet to be detected v~a a we~ght of the evidence approach Thus, the report mcludes stated
u~certamties and azeas where add~honal research ~s needed to better understand the ttue benefits and nsks
Strenaths and Limitations of Eoidemioloqv and Toxicoloqv Aaaroaches
The potenhal rtsks of exposure to fluonde among human populahons can be evaluated m essenhally two
ways In the first approach, laboratory ammals are tested under controlled conditions and exposed to
known quanhhes of fluonde m water or food for varymg lengths of t~me Tox~wlogical studies attempt to
denve dose-response relahonsh~ps between exposure to fluonde and some measure of orgamsmal
response Measured responses may mclude moRahry, changes m growth, reproductrve capac~ty or the
mc~dence of cancerous lesions. In some studies, rodents are exposed over their entae lifetime, up to two
years These stud~es typically mclude hisrologic exammahon of tissues at the end of the study to detect
m~croscop~c lesions m mult~ple organs Doses of fluonde gtven to ammals are often much higher than
doses that would typ~cally be encountered by a person
Exhapolahon of dose-response toxtcity tests m ammals to the pred~ct~on of human nsks from drmkmg
water exposure to fluonde ~s complicated by many factors Fmdmgs must be extrapolated between the
differences m doses used m an~mal studies and the range of human exposures assoc~ated w~th the
consumphon of lmg/1(lppm) of fluonde m fluondated drmkmg water Ammal responses can vary
compazed to human responses, and there is always uncertamty associated with extrapolat~on from test
spec~es hke rodents to humans Absence of a dose-response relahonsh~p between a stressor and a response
is cons~dered strong ev~dence that the stressor is not l~kely to cause a response However, the absence of
any observed dose-response relat~onship between a stressor and a response does not prove that the
stressor cannot cause a response
The second approach to assessmg nsk to humans mcorporates epidemiolog~c studies of human
populauons. These studies mvolve companng the mc~dence of vanous potent~al health effects among
populahons exposed or not exposed to fluonde or comparmg the frequency of exposure to fluonde among
persons wdh and wrthout a certam disease The advantages of the ep~demiologic approach aze that they
Report of the Fort Collms Fluonde Techmcal Smdy Group - Apnl 2003
ue conducted m the species of mterest (humans), the exposures aze at relevant levels and the study ~s done
by observahonal, rather than expenmental methods under "natural" condrt~ons
The d~sadvantages of epidemiologic approaches aze that they may make u di~cult to accurately assess
exposure over hme due to lack of mdrvidual level data about d~et, water consumpt~on pattems, fluonde
concentrauons, etc These smdies are also sub~ect to a vanety of biases found m observational reseazch
Pnncipal sources of b~as m epidem~ologic studies mclude I) confoundmg - where there may be exposure
to another vanable that may be more common among those exposed that ~s aiso a nsk factor for the
d~sease, resulting m an over- or under-eshmate of the true nsk, 2) selechon b~as due to an mab~hty to
study enhre populahons, resultmg m a biased sample of part~c~pants whose exposures or disease pattems
are not representahve of the populahon from which they are drawn, and 3) mformat~on bias, where
mformahon about exposures, outcomes or other factors may be maccurate due to problems w~th recall,
res~dent~al mob~lity, lack of adequate exposure data and other data madequac~es
The FTSG reviewed the tox~wlogical and epidem~ological stud~es as mdependent hnes of evidence The
we~ght of evidence findmgs are stronger when the tox~cological and epidemiological stud~es agree.
However, erther lme of evidence may carry enough weight on its own to be convmcmg as to the benefits
or nsks of a particulu substance In one example, the EPA's recent rulmg to lower the max~mum
contammant level for azsemc m dnnkmg water from 50 µg/lrter to 10 µg/lrter came solely from
epidemiologic stud~es md~catmg an mcreased nsk of cancer m exposed human populahons Also m the
cancer azena, toxicologcal evidence may stand alone ~f a substance is tested repeatedly m several
exper~mental test species (such as rats, mice, and hamsters) at suitable doses, and a spec~fic cancer is
detected cons~stently m a sufficient proportion of test ammals The toxicolog~cal evidence is much
stronger when the same substance ~s also shown, m a variety of genet~c test systems, to have DNA-
damagmg effects (genotox~city) that have been associated w~th cancer m humans
Risk and Benefit Assessment and Risk Manaaement
The chazge of the FTSG was ro compile a report that assessed r~sks and benefits oF commumty
water fluondaUOn m order to assist the nsk managers (~ e, the Lazimer County Boazd of Health,
the C~ty of FoR Colhns Water Boazd, and the Fort Colhns C~ry Council) The FTSG found the
followmg explanahon of risk management by the Medical Reseazch Counc~l of Great Brrtam to be
paRiculazly useful
"Once the nsks and benefits have been assessed, this mformahon must be set alongs~de other
considerahons, such as the financ~al cost of the poltcy or achon, and a decision then made
on whether to ~mplement the change Th~s ~s not simply a matter of science - it mvolves
value ~udgments, and mdividuals may weight the nsks, benefits and attendant uncedamt~es
differently If the decis~on must be taken at the commumty level (as with water
fluor~dahon), ~t often falls to democrahcally elected representatrves and may follow wider
publ~c consultaUOn and debate" Reference c~ted Medical Research Counc~l (2002)
Workin~GrouQReoort Water Fluondat~on and Health London, U K John Wnght, p 7
Statutorv Authoritv for Fluoride Used in Communitv Water Fluoridation
The Umted States Env~ronmental Protect~on Agency (EPA), under the Safe Dnnkmg Water Act (42 USC
300), promulgates the Nahonal Pnmary Dnnkmg Water Regulat~ons. These regulahons set the max~mum
contammant levels (MCLs) for chemicals m fimshed water suppLed by pubhc water systems Based on a
report by the Nahonal Reseazch Council, the EPA has establ~shed an MCL for fluonde of 4 0 mg/L The
National Sanrtahon Foundahon (NSF) cernfies dnnkmg water additrves ~f khey aze shown to contnbute
less than 10% of the MCL to the fimshed water supply for all dnnkmg water contammants regulated by
the EPA As stated above, the level of fluoride m Fort Colims treated water supphes ~s stnngently
conuolled at 1 0 ppm (range from 0 7 to 1 2 ppm) The FoR Colims Ut~liues Water Tceatment Program
Introduct~on
comphes with all regulatw~s set forth by the EPA for fluonde, uses products that aze certified by the NSF,
and meeu or exceeds all recommendahons set forth by the Colorado Depaztment of Pubhc Health and
Environment (CDPHE) as well as by the Umted States Centers for Disease Conhol and Prevenuon (CDC).
Several mdrviduals at the miual publ~c meehngs suggested that fluonde should be treated as a drug that is
added to commumry water and wondered why the Umted States Food and Drug Admm~strat~on (FDA)
does not regulate fluonde m dnnkmg water The FTSG noted that FDA cons~ders the mtended use of
producu when determmmg whether or not an "art~cle" ~s a drug, as opposed to a cosmet~c, a food or
beverage, or none of these. The mtended use of the h~gh concentratwns of fluonde m toothpaste and other
dental products meets the FDA's defimtion of a drug, i e, drugs aze "(A) articles mtended for use m the
dia~os~s, cure, mmgahon, treatment, or prevenhon of disease and (B) art~cles (other than food) mtended
to aFfect the structure or any funchon of the body of man or other an~mals" [FD&C Act, sec. 201(g)(1)J.
Consistent w~th th~s definit~on, when fluonde is added to bottled water, the FDA regulates the product as
a food, because of its mteaded use The EPA, rather than the FDA, has the authority m the U S to
regulate mawmum levels of fluor~de m dnnkmg water In add~hon, the U S PubLc Health Service and
state public health authonhes aze charged with ~ssumg recommendations regazdmg opt~mal levels of
water fluor~dation for purposes of preventmg cazies, and the dec~s~on to fluondate water is left to the
impacted populahon's elected o~c~als The FTSG did not address queshons of legal defimt~ons or the
distnbuhon of regulatory authonty m mveshgat~ag the four outlmed ob~echves as previously stated
Imaortant Backaround Information Relevant to the Fluoridation of Communitv Water in
Fort Collins Coloredo
History of Fort Collins Water Fluoridation Progrem
In 1954, an ordmance to fluondate was presented to Fort Colhns voters, but d~d not receive suffic~ent
votes to pass In 1966, Ihe Fort Collms C~ty Council adopted an ordmance proh~b~hng fluondahon unless
approved by a vote of the publtc. Ctttzens voted m 1967 to authonze Ciry Council to add fluonde to Fort
Colhns water supply system. That yeaz Fort Coilms began addmg dry sodium s~hcofluonde to the treated
dnnkmg water supply at Water Treatment Plant #1 In 1992, the C~ty changed to a hqmd form of fluonde
called hydrofluorosihc~c ac~d (HZS~F6). This practice contmues ro the present.
Natural or Background Levels of Fluoride
The FTSG felt ~[ was ~mportant for the dectsion-makers and the general publ~c to know that the source
waters used by the C~ty of Fort Colhns (Cache La Poudre Rrver and Horsetooth Reservou) contam some
natural amounts of fluonde The levels m untreated water range from 0 15 - 0 25 mg/L fluonde ion This
is below the level considered by publ~c health authonUes to be `bphmal" for canes prevent~on Nahual
fluonde is not removed dunng the water treatment process If the C~ty were to end ~u water fluoridation
program, the dnnkmg water m Fod Collms would contmue to contam some fluonde
Fort Gollins A~ea Water Providers
In addit~on to Fort Collms UhLhes, there aze Uvee addihonal water uUlities servmg the Fort Collms azea
(East Lanmer County Water Distnct, Fort Collms-Loveland Water D~stnct and North Weld County
Water Dismct) Currently, Fort Colims Ut~hhes and these d~stncts fluondate at 1 mg/L Ne~ghbonng
districts somehmes share watec If Fort Co1Lns Uhl~hes ceased to fluondate the water and some or all of
the other d~stncts contmued to do so, some customers served by Fort Collms UtiLhes would recerve
fluoride m the drmkmg water rangmg &om 0 2 to I 0 mg/L Customers would need to contact theu
supplier to deteimme the level of fluonde m theu water
Review of Water Treatment Process Chemistry
Fort Colhns Utilit~es uses what ~s termed `Conventwnal TreatmenY for its two raw water sources Cache
La Poudre River and Horsetooth Reservou waters aze blended and then treated usmg several different
Report of the Fort Collms Fluonde Techmcal Study Group - Apn12003
chem~cals Each added treatment chem~cal ~s defined below and shown, begmntng from left to nght, on
F~gure 1
The water treatment chem~cals used at the Fort Collms Water Treahnent Facihty aze purchased or
prepazed m highly concentrated forms Many of these concentrated chemicals aze hazazdous pnor to the~r
addit~on to the raw (untreated) water. However, once added to the raw water, these cheuucals aze diluted
and become harmless, ~f not helpful. A fundamental concept m tox~cology that addresses th~s
phenomenon was first descnbed in the sixteenth century by Pazacelsus, "All substances are po~sons, there
~s none wh~ch ~s not a potson The nght dose d~fferentiates a poison from a remedy "
Thus, any review of the "safety° of dnaktng water add~hves must keep tn mmd that the dose determtnes
whether the additrve is helpful or poisonous
The reader should refer to F~gure I to rev~ew where each of the chem~cals descnbed below are added m
the treatment process
Raw Poudre
Rrver Waler
Raw Horsetooth
Reservar
Water
C~brlns Obxitle (Cpr)
PaWereO ActrvaOaC
Ca~bon
Lime (Ca(OHhI
~COn DIOMItlB (COe)
Fbw Biend
BnckgrouM
FluonEe = 0 2 mgit
~
CkamBll ~Pb
Stabon
1
ChbMe
~ms (CafOHhl
Cerbon DbaOe (CO~
FhromalAek acM (HFS)
(AGEaO FluaMe = 0 8 my/L)
Fort Collins Water Treatment Facility
Process Schematic
and
Location of Chemical Feed Points
F~gure 1
Sample
station To
2 ~-DistnbuGon
(ss2) System
Chlonne Diox~de (CIOZ) - used as a pre-oxidant for Horsetooth Reservo~r raw water to aid m the removal
of certam contammants CIOZ ts made on s~te usmg a highly automated process Chlonne, sodmm
chlonte, and water aze blended to fotm chlorme d~ox~de soluhon The solution vanes m strength and
dosage based on raw water quahty CIOZ ~s a strong ox~dant and requ~res spec~al handlmg and feed
eqwpment CIOZ d~sassociates to chlonte and chlorate ~ons as we-I as choru~e and hydrogen ions
Powdered Act~vated Carbon (PAC) - PAC is used for removmg compounds that cause tas[e and odor
PAG is added at dosages dependant upon raw water quai~ty cond~hons Carbon does not change chem~cal
form after addit~on and ~s settled out oF the process after addmon
Alum (AI~(SOJ> H~O)
~ Coagulatwn
WBS~
Reservov
Polymem (Ilocculantaidand fitlerad)
Fbcculatwn 8 ~
Sedimenta6on Filtrahon
East
Reservov
FluOriEe = 1 0 mdL ~ ~ FluonOe =1 0 mglL
Introduchon
Calcmm Hvdrox~de or Lime [Ca(OH)2] - L~me ~s added to the raw water to ad~ust the alkahmty of We
raw water pnor to coagulahon AlkaLmty is a measure of the bu£fenng capac~ty of the water and is
ryp~cally expressed as mg/I of calcmm carbonate (CaCO;) When hme is added to water, calcium ions are
released and the alkahmty and pH go up (due to the mcrease m OH' that is released from the lime)
Dosages vary from 5- 35 mg/L. Lune ~s very bas~c (pH => 10 5)
Cazbon Dioxide (COZ) - COZ gas ~s used to ad~ust the pH of the raw water after Lme addihon (see L~me)
COZ forms a weak acid when added to water - carbomc ac~d (HZC03)
Alummum Sulfate or Alum (AIZ~SOa)s+ 14HZ0) - Alum ~s added to the water to coagulate the part~cles
that are present m raw, untreated water Smce alum is posttrvely chuged, and most panc~les are
negahvely charged, the particles agglomerate m the flocculat~on stage, and settle out m the umt process
called sed~mentahon Alum is sltghtly ac~dic (pH of I% soluhon = 3.5) When alum ~s added to water,
the salts dissociate to their respectrve trrvalent ions, Al"' and then form hydroxyl complexes
{AI(HZO)6"}
Polvmers (Cat~omc and Amomc)- Polymers aze added to the process to a~d m setdmg the lazger partwles
that are formed m the coagulahon and flocculauon processes D~fferent rypes of polymers aze uUl~zed
dependmg on the raw water source and quahty Dosages are applied at very low concentrations (0 O] -
0 2 mg/L) Smce polymers aze long chamed organ~c compounds, they do not change forcn and ue
removed with the particles that aze settled and filtered out of the water
Chlonne (Clz) - Chlonne is added to d~smfect the water after filuat~on Although chlonne ~s hazazdous as
a gas form, when added to water, ClZ d~sassoc~ates to hypochlorous ac~d (HOCI') and hydrochlonc acid
(HCl) The HOCI' ~s the forcn that dismfecu the water posages apphed are dependant upon many water
quaLty factors, however regulat~ons requue that a mm~mum of 0 2 mg/L Cl2 remam m the water at the
furthest end of the pipmg system that dehvers water [hroug6out our commumty
Lime - Lime ~s also added at the clearwell to ad~ust the alkalm~ty of the firushed, potable water (38 - 40
mg/L as CaC03) Alkalmrty ~s a measure of the buffenng capac~ty and ~s typ~cally expressed as mg/L as
calcmm cazbonate (CaC03) Agam, when hme ~s added to the water, calcmm ions are released and the pH
goes up (due to the mcrease m OH" that is released from the l~me)
Carbon D~ox~de - See above COZ is used to ad~ust the pH of the fimshed, potable water COZ fomis a
weak ac~d when added to water - carbomc acid (HZC03) The final pH target for our commumry is stnctly
controlled (pH 7 8- 8 0 umts)
Fluorosil~cic Acid (HFS or HZSiFb) - Fluonde is added as a liqu~d w~th very precise metermg and flow
measurement eqmpment L~qmd HFS ~s acid~c and once added to water, ~t dissoc~ates and will lower the
pH of the solution In Fort Collms, both lime and cazbon d~ox~de aze added to mamtam stnct pH targets of
Ihe fimshed water (see Figure 2)
Report of the Fort Colims Fluonde Techmcal Smdy Group - Apnl 2003
Raw Poutlre
RNer Water Fbw Floccula4on 8
Blend Coapuladon Setlimentetan FiNraLOn
Raw Hwsetooth
Resarvoir Background
W~r Fluwitle = 0 2 mg/L
Claanvell ~ ~
~ S~atnn
1
HFS FEED WeS~ East
(qdd~y Reservoir Raservo~r
FluotlOe
= 0 8 mglL) fluonde ~ 1 0 mglL Fluonde = 1 0 mglL
Fort Collins Water Treatment Facility
Process Schematic Sample
Stadon To
and 2 Distnbu
Location of HFS (Fluoride) Feed ~SSZ> System
F~gure 2
When HFS is added to water, hydrofluonc acid (HF) and s~l~con tetrafluonde (S~F4) aze formed Si6ca
tetrafluonde is a gas that reacts quickly with water to form silic~c ac~d (HZS~O3) or sil~ca (SiOZ) and HF.
The HF further dissociates to hydrogen and fluonde ion The concentrat~on of fluonde ~s stnctly
controlled to a target level of 1 mg/L as fluonde ~on
Overview of Fluoridation Chemistry
M overnew of the chemistry of HFS addmon and what happens when ~t ~s dissolved m water is
provided Another overview, wntten by an mdependent research group commissioned by the Bnus6
Fluondation Soc~ery can be found at htto //www l~v ac uk/bfshvrcreport ndf. For detailed recent sc~enhfic
reviews of this issue, the reader should consult Urbansky and Shock, 2000 and Urbansky, 2002
Equilibrium
The equil~bnum reaction between the strong ac~d hexafluorsil~cic acid (HFS) and water can be
represented m chemical shodhand as.
SiFb=' + 4HZ0 --~ Si(OH)4 + 4H~ + 6F
The dissociahon of hexafuors~l~cate ion (S~F62') to the products on the nght hand s~de of the above
equatton ~s considered to be complete at equilibnum at the normal pH of mumc~pal water supplies (pH >
7 0) In Fort Collms, the pH ~s sh~ctly mamtamed a[ a range of 7 8- 8 0 pH umts Complete d~ssociat~on
at equil~bnum means chemists would repoR, based on the most conservahve (smallest) eqwhbnum
constants m the chemical l~terature, that the ratto of StOH-0/SiF62" at pH 8 and a F- concentrahon of 1 mg/L
would be about 1 x 10E26 07 That means that for every 1 molewle on non-dissociated S~FbZ" there are
10,000,000,000,000,000,000,000,000 molecules oF Si(OH)4 The resultmg concentrahon of S~FbZ" at
equil~bnum m druilcmg water suppl~es where F' is adjusted w~th HFS to be 1 mg/L would be exceedmgly
small («< ] P~ per tnll~on)
Introducuon
The t~me to achieve this equdibnum is not prec~sely known However, u ~s known to occur withm m
seconds, ~f not mmutes, m complex aqueous chem~stry. Smce rt takes more than six hours for treated
dnnkmg water to reach Fort Collms homes, there ~s more than ample hme for SiFbZ' to reach eqmLbnum
(i e, to essenhally fully dissoc~ate) before any resident ingests t6e treated water
Further val~dahon of the dissoc~at~on of HFS to F dunng Fort Collms water treatment comes from the
chemical mass balance calculauons between the known amount of added HFS and the resulhng measured
F- ~on concentraUon presented m Append~x A-2. If lazge amounu of HFS were not dissoc~ated u would
be observed m the mass balance of HFS dosage versus the resultmg F~on concentrahon
It ts important to put the mass balance findmgs mto the context that no more than 66% d~ssoc~ation was
determmed by the Westendorf, 1975 thes~s c~ted by Masters et a12000 (See Fmdmg #4) Th~s thesis
findmg is the "expenmental ev~dence" c~ted to call mto queshon the Irterature dissociahon constants
suggestmg nearly 100% dissociat~on reported by Urbansky and Schock 2000, and Urbansky 2002 Smce
the mass balance usmg the F" ion electrode method (ISE) is balanced withm 3% (Mass Balance
CalculaUOns, Appendix A-2), the Fort Collms Water Treatment Fac~hry (FCWTF) momtonng data does
not support the cla~m that 33% or more of the HFS added is undissoc~ated and remams m the water
supply for Fort Colhns The mass balance reported an error of 3% and hence the analytical result
demonstrates the d~ssociahon of the F~on Grven the prec~s~on m the values used for flow rate, applted
dosage rate, HFS added m pounds per day, and the F" ~on concenhahon, the budget +/- 3%~s withtn
measurement erzor The FCWTF data aze cons~stent w~th the predicnon of complete dissociahon of HSF
based on chem~cal equihbnum [heory
10 Report of the Fort Collms Fluot~de Techmcal Study Group - Aprt12003
~-~uG~ w~eh-~ ~
CITY OF BOULDER, COLORADO
BOARDS AND COMMISSIONS MEETING SUMMARY FORM
NAME OF BOARD/COMMISSION: Water Resources Adv~sory Board
DATE OF MEETING: May 21, 2001
NAME/TELEPHONE OF PERSON PREPARING SiJMMARY: Robm Madel, 303-441-4073
NAMES OF MEMBERS, COUNCIL, STAFF AND INVITED GUESTS PRESENT:
BOARD MEMBERS - Robert Fiehweg, Jeannette Hillery, Cal Youngberg, V~ck~ Naber, Gil Barth
STAFF - Ned Williams, Chns Rudlan, Randy Cnttendon, Ridge Dorsey, Brad Segal and Robm Madel, secretary
WHAT TYPE OF MEETING (BOLD ONE) (REGULAR] [SPECIAL] [QUASI-NDICIAL]
Agenda Item 1- Call to Order
The meehng was called to order at 7 07 p m
Agenda Item 2- Approval of Apri116, 2001 Meehng Minutes
Jeannette H~Ilerv moGoned to approve t6e minutes.
V~cln Naber seconded.
The motion passed unanimously, 4-0. Cal Youngberg was not there yet.
Agenda Item 3- General C~hzen Partic~pahon
There was none
Agenda Item 4- Sta1'f update and discussion on drinkmg water fluor~dahon (Staff - Chris Rudkin and
Randy Crittendon).
Ned Wilhams mtroduced the topic and why ~t is bemg presented at the meehng He sa~d there have been a number
of newspaper articles about fluondahon m dnvkmg water that has led to the Envuonmental Advisory Boazd
(EAB) to discuss ~t at theu next meetuig on June 14, 2001 The EAB w~ll be takmg a vote of support or dissent
about the ~ssue
Chns Rudkm wanted to prov~de the WRAB with up-to-date mformahon about fluondahon of dnnking water He
discussed several stud~es that had been perfom~ed to evaluate the effects of fluondahon He also d~scussed the
recent decis~on by the Ft Collms Water Boazd to recommend discontmumg fluondahon of dnvkmg water He
reviewed the lustory of fluondahon m Boulder and referenced the recent cit~zen survey that showed only 25% of
respondents are sl~ghtly or strongly opposed to fluondahon
WRAB Questions
WRAB queshons covered the followu~g
• The dec~s~on m Ft Collms
• Appropnate mechamsms for fluondahon (~f inethods other than dnnkmg water are used)
• Queshons/concerns about fluondahon from the Web stte
• The survey results
• The benefits of fluondahon
• The pos~hons of the state and counry health departrnents
• The s~tuahon m Colorado Spr~ngs
• The existence of a mechaiusm to momtor for negahve ef~'ects
• Negahve effects or potenhal negahve effects
• The momtonng and distnbuhon system m place m Boulder
• The source and form of the fluonde used m Boulder
Citizen Particioat~on and WRAB Comment
Water Resources Adv:sory Board
Summary Mtnutes
May 2!, 2001
Page !
Henrv Eaton, 2180 Sunshine Canyon Dr., Boulder, ts a retued denhst that led the campa~gn to get Boulder to
fluondate its water m 1969 He sa~d m lus opuuon there has never been as effechve or safe a pubhc
health ~ssue as t}us He said the ongmal studies came from Colorado Spnngs, which has three t~mes the
dnnkmg water hmrt of nahually occurnng fluonde m theu water He said that fluorosis (whrte spots on
teeth) was the only problem reported In lus dental prachce he used to see a lot of cavmes and tooth
decay, especially m cluldren but he said it almost disappeazed after fluondahon began He ~s amazed by
the comment made by the board m Ft Collms that Wey will save money by not admuustenng fluonde
now that tooth decay is no longer a problem He feels ttus is a health matter and not an EAB matter and
he sa~d he spoke with the c~ty attomey who agreed wrth hvn He explamed the process by wluch fluonde
helps prevent tooth decay He spoke abou[ the previous elechons that attempted to end fluondahon and
about how nasty those campa~gns go[
WRAB Comments
Jeannette Hillery asked if any longevity studtes had been done m Colorado Spnngs Henry said he had been out of
denhslry for 20 years but he didn't thmk any lmks had been found between d~seases and fluondahon He also
pomted out that with 175 isulhon people recervmg fluondated water, ~f there were any lu~ks they would show up
very cleazly
The WRAB agreed that the issue belongs with the county and state health boazds The EAB meetmg w~ll be June
14, 2001 at 6 00 p m at 1720 13'" St Bob Fiehweg and Cal Youngberg agreed to attend the meehng If the EAB
votes agau~st fluondahon, the City Council could decide to hold an elechon on rt, m which case they would
probably have the WRAB evaluate it and make a formal recommendahon
Agenda Item 5- Statt overview and discussion on t6e Industrial Pretreatment Program (Staf[- Ridge
Dorsey).
Rid e D~orsey gave a presentahon about the program He spoke from shdes that were mcluded m the packets He
satd the same presentahon had been grven to a group of consultants and the Colorado Department of Public
Health and the Envuonment
Shdes covered the follow~ng topics
The Defuuhon of Industnal Pretreatment
The Goais of the Program
Implementat~on of the Program
PretreatrnentAuthonty
PretreatrnentStandards
Genera] Protvbit~ons of Pretreatrnent
Spec~fic Protubihons of Pretreahnent
Local Lucuts
Federal Lumts
The "nuts and bolu" of Local Luruts
Enforcement
Types of Noncomphance
Factors Deteim~mng Response [o Noncompl~ance
Tools to Deter Violators
Pro-actrvrty m Boulder
C~t~zen Participatiou and WRAB Comment
There was none
Water Resources Advtsory Board
Summary Mtnutes
May 21, 1001
Page 2
WRAB OaesLons
WRAB queshons covered the followu~g
• How compames can get mfo about the IP Progam
• The PACE Program
• The last co hance audit done b the c~
Agenda Item 6 -
A. Matters Gom the Board
• Jeannette Hillery said that she had gone to all of the South Boulder Creek reach meehngs and she's look~ng
forwazd to the update that w~ll be grven next month She said the meehngs have been produchve and Alan
Taylor is domg an outstandu~g ~ob
B. Matters trom the Staff
• Ned Williams reported that the Wonderland Creek pro~ect ~s underway and the ma~or excavahon work is
done for the channel
• Ned Wilhams reported that there would be three Barker Reservou meehngs dunng the summer The
secretary will e-mail ffie dates of the meehngs to the WRAB members
Agenda Item 7- Discussion of Future Meeting Dates and Agenda
There are two meetutgs m June
1 The regulaz meehng on June 18, 2001, wluch w~ll cover the South Boulder Creek Floodplan, The 2002
budget, CIP and rate ~ncreases and the Inter-Governmental Agreement wrth Lafayette
2 A ~omt meehng wrth the TAB to discuss the Greenways Program CIP on June 25, 2001 at 7 or 7 30 p m at a
locahon to be detemvned
Agenda Item 8 - Ad~ournment
The meetu~g was ad~ourned at 8 53 p m
Date, Time, and Locat~on of Next Meeting:
June 18, 2001, 7 00 p m, regular meetmg, at the City Yazds m the Cafetena
June 25, 2001, Greenwa s Pro am CIP, at a tune and locahon to be detemuned
Water Resources Advuory Board
Summary Mrnutes
May 21, 2001
Page 3