Fluoride

City of Tucson

Fluoride occurs naturally in surface and groundwater and is also added to drinking water by many water systems. Read More.

Fluoride has been promoted as a chemical that reduces dental cavities. Yet it is now well-established that fluoride primarily exerts its protective effects through topical mechanisms, such as sodium fluoride in toothpaste and mouthwash. In contrast, long-term ingestion of fluoride in water increases dental fluorosis, which includes mottling, pitting and weakening of the teeth. EPA's maximum legal limit is set at 4 parts per million (ppm) to prevent skeletal fluorosis, a condition where bones become brittle and more susceptible to fractures, although these effects may occur at lower doses.

Even fluoride levels of 0.7 ppm, the amount of fluoride in drinking water recommended by the U.S. Public Health Service, can result in too much fluoride for bottle-fed babies. EWG recommends that caregivers mix baby formula with fluoride-free water. The National Toxicology Program is investigating the potential for low doses of fluoride to alter thyroid function and childhood brain development.

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206

Samples

Samples exceeding legal limit (MCL)

Samples exceeding
health guidelines

Testing results - average by year

Year	Average result	Samples taken	Detections	Range of results
2013	N/A	0	0	N/A
2014	N/A	0	0	N/A
2015	N/A	0	0	N/A
2016	0.238 ppm	108	102	ND - 1.17 ppm
2017	N/A	0	0	N/A
2018	N/A	0	0	N/A
2019	0.301 ppm	98	98	0.119 ppm - 1.11 ppm

ppm = parts per million

State and national drinking water standards and health guidelines

EPA Maximum Contaminant
Level (MCL) 4 ppm

ppm = parts per million

All test results

Date	Lab ID	Result
2016-01-11	L160042-01I	0.202 ppm
2016-01-11	L160042-03I	0.133 ppm
2016-01-11	L160042-04I	0.336 ppm
2016-01-12	L160043-01I	0.171 ppm
2016-01-12	L160043-02I	0.155 ppm
2016-01-12	L160043-03I	0.230 ppm
2016-01-12	L160043-04I	0.164 ppm
2016-01-12	L160043-05I	0.329 ppm
2016-01-13	L160045-02I	1.17 ppm
2016-01-13	L160045-04I	0.244 ppm
2016-01-13	L160045-05I	0.186 ppm
2016-01-14	L160046-01I	0.199 ppm
2016-01-14	L160046-03I	0.213 ppm
2016-01-14	L160046-04I	0.377 ppm
2016-01-14	L160046-05I	0.341 ppm
2016-01-19	L160066-01I	0.140 ppm
2016-01-19	L160066-02I	0.147 ppm
2016-01-19	L160066-03I	0.162 ppm
2016-01-19	L160066-04I	0.321 ppm
2016-01-19	L160066-05I	0.132 ppm
2016-01-20	L160068-01I	0.188 ppm
2016-01-20	L160068-02I	0.179 ppm
2016-01-20	L160068-03I	0.490 ppm
2016-01-20	L160068-04I	0.154 ppm
2016-01-20	L160068-05I	0.308 ppm
2016-01-21	L160069-01I	0.136 ppm
2016-01-21	L160069-02I	0.138 ppm
2016-01-21	L160069-03I	0.178 ppm
2016-01-21	L160069-04I	0.238 ppm
2016-01-21	L160069-05I	0.229 ppm
2016-01-25	L160091-01I	0.220 ppm
2016-01-25	L160091-02I	0.204 ppm
2016-01-25	L160091-03I	0.214 ppm
2016-01-25	L160091-04I	0.137 ppm
2016-01-25	L160091-05I	0.166 ppm
2016-01-26	L160092-01I	0.162 ppm
2016-01-26	L160092-03I	0.167 ppm
2016-01-26	L160092-04I	ND
2016-01-26	L160092-05I	0.368 ppm
2016-01-27	L160094-01I	0.196 ppm
2016-01-27	L160094-02I	0.139 ppm
2016-01-27	L160094-04I	0.153 ppm
2016-01-27	L160094-05I	0.351 ppm
2016-01-28	L160104-02I	0.179 ppm
2016-01-28	L160104-03I	0.452 ppm
2016-01-28	L160104-04I	0.637 ppm
2016-01-28	L160118-01	0.278 ppm
2016-02-01	L160119-01	0.763 ppm
2016-02-01	L160119-03I	0.316 ppm
2016-02-01	L160119-04I	0.282 ppm
2016-02-02	L160122-01I	0.264 ppm
2016-02-02	L160122-02I	0.234 ppm
2016-02-02	L160122-03I	0.281 ppm
2016-02-02	L160122-04I	0.293 ppm
2016-02-02	L160122-05I	0.330 ppm
2016-02-03	L160123-01I	0.153 ppm
2016-02-03	L160123-04I	0.210 ppm
2016-02-04	L160125-01I	0.259 ppm
2016-02-04	L160125-02I	0.289 ppm
2016-02-04	L160125-03I	0.416 ppm
2016-02-04	L160125-04I	0.264 ppm
2016-02-08	L160143-02I	0.195 ppm
2016-02-08	L160143-03I	0.151 ppm
2016-02-08	L160143-05I	0.200 ppm
2016-02-09	L160144-02I	0.160 ppm
2016-02-09	L160144-03I	0.210 ppm
2016-02-09	L160144-04I	0.242 ppm
2016-02-09	L160144-05I	0.268 ppm
2016-02-10	L160145-03I	0.195 ppm
2016-02-10	L160145-04I	0.252 ppm
2016-02-10	L160145-05I	0.174 ppm
2016-02-11	L160148-01	0.132 ppm
2016-02-11	L160148-02T	0.154 ppm
2016-02-11	L160148-04T	0.136 ppm
2016-02-11	L160148-05I	0.158 ppm
2016-02-11	L160171-01I	0.124 ppm
2016-02-16	L160172-03I	0.116 ppm
2016-02-16	L160172-04I	0.173 ppm
2016-02-17	L160173-01I	0.158 ppm
2016-02-17	L160173-02	0.194 ppm
2016-02-18	L160178-04	0.172 ppm
2016-02-23	L160210-01	0.274 ppm
2016-02-23	L160210-02	0.102 ppm
2016-02-23	L160210-03	0.176 ppm
2016-02-24	L160211-01J	0.115 ppm
2016-02-24	L160211-02J	ND
2016-02-24	L160211-03J	0.138 ppm
2016-02-25	L160212-03	ND
2016-02-29	L160245-01	0.177 ppm
2016-02-29	L160245-02	0.133 ppm
2016-03-01	L160246-03J	0.165 ppm
2016-03-02	L160247-01	0.287 ppm
2016-03-07	L160268-02J	0.117 ppm
2016-03-10	L160280-02J	0.239 ppm
2016-03-10	L160280-03T	0.135 ppm
2016-04-20	L160468-01	0.585 ppm
2016-04-27	L160497-05	ND
2016-04-28	L160498-01	0.511 ppm
2016-04-28	L160498-02	ND
2016-04-28	L160498-04	0.762 ppm
2016-05-02	L160516-01	0.629 ppm
2016-05-03	L160517-01	ND
2016-05-05	L160525-02	0.102 ppm
2016-05-31	L160656-01I	0.441 ppm
2016-05-31	L160656-02I	0.443 ppm
2016-06-14	L160697-01I	0.154 ppm
2016-06-16	L160723-01I	0.337 ppm
2016-10-04	L161215-01	0.166 ppm
2019-03-19	L190423-01 IOC	0.698 ppm
2019-04-01	L190499-02	0.431 ppm
2019-04-01	L190499-03	0.246 ppm
2019-04-01	L190499-05	0.441 ppm
2019-04-01	L190499-06	0.218 ppm
2019-04-04	L190541-01	0.211 ppm
2019-04-11	L190512-01	0.183 ppm
2019-04-11	L190512-02	0.196 ppm
2019-04-11	L190512-03	0.223 ppm
2019-04-11	L190512-04	1.11 ppm
2019-04-15	L190597-01	0.244 ppm
2019-04-15	L190597-02	0.266 ppm
2019-04-15	L190597-03	0.213 ppm
2019-04-15	L190597-04	0.802 ppm
2019-04-17	L190610-01	0.224 ppm
2019-04-17	L190610-03	0.181 ppm
2019-04-18	L190624-01	0.268 ppm
2019-04-18	L190624-02	0.217 ppm
2019-04-18	L190624-03	0.407 ppm
2019-04-23	L190640-01	0.423 ppm
2019-04-23	L190640-02	0.305 ppm
2019-04-23	L190640-03	0.700 ppm
2019-04-23	L190640-04	0.380 ppm
2019-04-24	L190645-02	0.160 ppm
2019-04-24	L190645-03	0.191 ppm
2019-04-25	L190648-01	0.231 ppm
2019-04-25	L190648-02	0.214 ppm
2019-04-25	L190648-03	0.223 ppm
2019-04-30	L190670-01	0.491 ppm
2019-04-30	L190670-02	0.187 ppm
2019-05-01	L190678-02	0.371 ppm
2019-05-01	L190678-03	0.317 ppm
2019-05-01	L190678-04	0.387 ppm
2019-05-02	L190690-01	0.155 ppm
2019-05-02	L190690-03	0.298 ppm
2019-05-06	L190704-03	0.263 ppm
2019-05-07	L190712-01	0.212 ppm
2019-05-07	L190712-02	0.185 ppm
2019-05-07	L190712-03	0.246 ppm
2019-05-08	L190725-01	0.338 ppm
2019-05-08	L190725-02	0.222 ppm
2019-05-09	L190728-01-20131	0.247 ppm
2019-05-13	L190741-01-20131	0.215 ppm
2019-05-13	L190741-02-20131	0.169 ppm
2019-05-14	L190748-02-20131	0.480 ppm
2019-05-15	L190761-01-20131	0.370 ppm
2019-05-15	L190761-02-20131	0.210 ppm
2019-05-15	L190761-03-20131	0.309 ppm
2019-05-20	L190783-02-20131	0.192 ppm
2019-05-20	L190783-03-20131	0.332 ppm
2019-05-28	L190813-01-06260	0.186 ppm
2019-05-28	L190813-02-06260	0.291 ppm
2019-05-28	L190813-03-06260	0.202 ppm
2019-05-28	L190813-04-06260	0.221 ppm
2019-05-30	L190835-01-06260	0.516 ppm
2019-05-30	L190835-02-06260	0.850 ppm
2019-05-30	L190835-03-06260	0.352 ppm
2019-05-30	L190835-04-06260	0.502 ppm
2019-05-30	L190835-05-06260	0.450 ppm
2019-05-30	L190835-06-06260	0.488 ppm
2019-06-03	L190837-01-06260	0.204 ppm
2019-06-03	L190837-02-06260	0.245 ppm
2019-06-03	L190837-03-06260	0.181 ppm
2019-06-03	L190837-04-06260	0.174 ppm
2019-06-03	L190837-05-06260	0.453 ppm
2019-06-04	L190851-01-06281	0.188 ppm
2019-06-04	L190851-03-06281	0.156 ppm
2019-06-04	L190851-04-06281	0.564 ppm
2019-06-04	L190851-05-06281	0.224 ppm
2019-06-06	L190879-01-06281	0.215 ppm
2019-06-06	L190879-02-06281	0.232 ppm
2019-06-06	L190879-03-06281	0.285 ppm
2019-06-06	L190879-04-06281	0.313 ppm
2019-06-06	L190879-05-06281	0.324 ppm
2019-06-11	L190893-01-06281	0.162 ppm
2019-06-11	L190893-02-06281	0.307 ppm
2019-06-11	L190893-03-06281	0.248 ppm
2019-06-11	L190893-04-06281	0.307 ppm
2019-06-13	L190907-01-07081	0.331 ppm
2019-06-13	L190907-02-07081	0.207 ppm
2019-06-13	L190907-03-07081	0.223 ppm
2019-06-13	L190907-04-07081	0.138 ppm
2019-06-25	L190968-01-07081	0.247 ppm
2019-06-27	L190983-01-08131	0.580 ppm
2019-08-20	L191266-01-10011	0.238 ppm
2019-08-20	L191266-02-10011	0.241 ppm
2019-08-22	L191282-01-10011	0.183 ppm
2019-08-22	L191282-02-10011	0.169 ppm
2019-09-09	L191400-01-10011	0.308 ppm
2019-09-09	L191400-02-10011	0.119 ppm
2019-09-10	L191408-01-10011	0.205 ppm
2019-09-11	L191425-01-10011	0.190 ppm
2019-09-11	L191425-02-10011	0.186 ppm
2019-09-11	L191425-03-10011	0.250 ppm
2019-09-12	L191433-01-10011	0.335 ppm
2019-09-16	L191452-01-10021	0.292 ppm
2019-11-19	L191822-01-01071	0.228 ppm
2019-11-20	L191829-01-01071	0.232 ppm