Derrick Broze Profile picture
Feb 13 28 tweets 4 min read Read on X
Day 9 of the 2nd phase of the #FluorideLawsuit is resuming with EPA witness Dr. Stanley Barone.
EPA attorney Brandon Adkins wants to talk to Barone about the BMCL (Benchmark Concentration Level)
EPA is first asking Barone about the ability to translate a urinary fluoride level into a fluoride intake level.

Barone says this is not possible (as was testified to by previous FAN witness).
EPA asking Barone about the Physiologically based pharmacokinetic (PBPK) Model and in what cases the EPA will use such a model.
Barone is explaining to Judge Chen his view that several studies show "a lack of linearity" below the 1 mg/L water fluoridation levels.

Barone and the EPA are trying to convince the judge that the effects of fluoride are too unclear below 1 mg.
Judge Chen asks Barone if the Thippeswamy study found more linearity above the 1 mg/L level.

Barone agrees with qualifications.
Judge Chen and Barone are still going back and forth.

Again, this is an example of how the judge seems genuinely interested in getting to the bottom of the science here. He isn't blindly following the govt, and he isn't necessarily on the plaintiffs "side" either.
Barone and Judge Chen discussing absorption of fluoride and excretion.

Judge Chen is wondering if its possible to determine how much fluoride is being absorbed and how much is actually being excreted by the body.

Judge Chen wraps up his questions.
EPA continues questioning of Barone...

Barone says there's more to this equation than just intake of fluoride.

EPA shows Barone a bar graph used by plaintiffs which shows levels of Maternal Urinary Fluoride levels, comparing fluoridated to non-fluoridated populations.
The data from table is from Till, 2018, in the Third Trimester.

EPA asks Barone if what the table shows is accurate. Barone says no. He doesnt think the use of fluoride intake levels are sufficient enough for drawing conclusions.
EPA: Why would you need to do source apportionment for a risk evaluation under TSCA?

Barone: we want to understand what risk is attributed to Condition of Use (COU), in this case, what proportion is attributable to water fluoridation.
Judge Chen has some questions about the Till, 2018, bar graph.

He points to the differences between urinary fluoride concentration, and women in fluoridated areas and non. What else could be account for this difference?
Barone says the analysis here is purely looking at biomarker levels.

Judge Chen: so if women in fluoridated areas have different habits than that could explain these differences?

Barone: It could. What we dont have from this graph is variability and that would account for it.
Judge Chen asking about the source apportionment that was just mentioned.

Barone says the EPA has to understand the COU to be able to understand the risk.
Barone is explaining the risk analysis to Judge Chen using horseshoes as an analogy.
Judge Chen: is there any reason why the EPA in its rulemaking process for TSCA wouldn't do more studies about apportionment?

Barone says that's not the practice, not sure if its prohibited. He says bc TSCA is risk based, they have to have a risk assessment to act.
EPA continues questioning of Barone.

EPA asks Barone if there are any other environmental standards within the EPA that use the COU.

Barone says this is very TSCA specific.
EPA now reading statement to Barone from the EPA redgarding another compoundl NMP (N-Methyl-2-pyrrolidone).

EPA asks Barone about the process EPA used to determine risk with NMP.
EPA goes back to the bar graph from Till, 2018.

EPA: if we were to assume that the 2.41 mg/L level is aggregated data, that level is still below what the NTP found a statistically significant association, correct?

Barone agrees.
Judge Chen has more questions, this time about the process for studying NMP. Asks if the data on NMP was separated into sources of exposure.

Barone answers, and mentions animal studies.
Judge Chen: so animal studies obviously played a big role in that risk assessment...

Barone: it did. Says there was limited human data.
Judge Chen: seems when you dont have as much human data and you have to rely on the animal studies, I see where you put a premium on the PBPK model, is that fair?

Barone agrees, explains the different times they might use a PBPK model.
(this is important bc the EPA has argued the FAN relied too heavily on animal studies that shouldnt be used to make a hazard assessment on fluoride.)
EPA asks Barone if there is enough data to get to the hazard evaluation step of TSCA?

Barone: no. I dont think we can move to determining a threshold or a POD with the current evidence we have.
Barone: The science isn't settled. Making a risk determination with this quality of evidence is highly undesirable.

EPA: and the NTP did not produce a Point of Departure?

Barone: They did not.
EPA: and Dr. Thiessen didnt produce or justify a POD?

Barone: no. I heard a bunch of inferences and vague assumptions which doesnt satisfy TSCA.
EPA: in your view, does the weight of the scientific evidence support selecting a point of departure for water fluoridation at (names several different measurements in mg/L).

Barone: I dont think we have enough evidence to pick a POD around the 1.5 mg/L.
EPA ends their questions with Dr. Barone.

FAN Connett asks for a 5 minute recess before they begin their cross of Barone.

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More from @DBrozeLiveFree

Feb 13
The 9th day of 2nd phase of the #FluorideLawsuit resumes with FAN attorney Michael Connett cross examining EPA witness Dr. Stanley Barone.
FAN: you agree that fluoride has been found to be a neurotoxin at certain levels?

Barone: yes.

FAN: you agree that there is an association of neurotoxicity with water fluoridation above levels of 2 mg/L?

Barone: at some level above 2, yes.
FAN: let's talk about the NTP. The NIEHS is one of the premier environmental research institutes in the world, correct?

Barone agrees.

FAN: the NTP has a well earned reputation for producing reliable assessments on toxicity, correct?

Barone agrees.
Read 43 tweets
Feb 12
The final session of day 8 of the 2nd phase of the #FluorideLawsuit resumes.

EPA is going over Dr. Barone's previous testimony to counter FAN's Michael Connett objection that Barone is being asked to share opinions which go beyond his deposition.
EPA still highlighting Barone's testimony that they believe shows he had previously discussed linear modeling and other topics which FAN Connett says are beyond the scope of previously expressed opinions.
FAN Connett is responding to EPA's comments, clarifying how he still believes Barone is being asked to go beyond his deposition.
Read 28 tweets
Feb 12
Day 8 of the 2nd phase of the #FluorideLawsuit resumes.

FAN Attorney Michael Connett begins 2nd cross on EPA expert witness Dr. David Savitz.
Connett is asking about the Taher 2024 study decision to use a "benchmark dose modeling of moderate dental fluorosis in the Dean (1942) data".

Connett asking Savitz about the data around the Dean 1942 study relating to race, etc.

Savitz says he is not aware of the details.
Connett shows Savitz the NTP 2016 monograph. Connett wants to focus on the conversation relating to the 1-2 mg/L range.
Read 42 tweets
Feb 12
Day 8 of the 2nd Phase of the #FluorideLawsuit is beginning.

Judge Chen just walked in the court. FAN Attorney Michael Connett will continue his cross examination of Dr. David Savitz.
EPA attorney Brandon Adkins and FAN Michael Connett are working out some scheduling issues with Judge Chen.
Read 88 tweets
Feb 9
The final session of Day 7 of the 2nd phase of the #FluorideLawsuit is beginning.

FAN attorney Michael Connett will be cross examining the EPA's witness, Dr. David Savitz.
Connett pulls up a book written by Savitz titled, Interpreting Epidemiologic Evidence.

Connett quoting directly from Savitz, where he states that "inaction is still an action", in terms of assessing risk.
Connett reads more from Savitz, EPA objects, suggests that these are long quotes and should be shown to Savitz.

Savitz says he agrees with his own words, but his goal with writing this was that epidemiologists need to have an "even handed" approach when drawing conclusions.
Read 47 tweets
Feb 9
The 2nd session of Day 7 of the 2nd Phase of the #FluorideLawsuit has resumed.

EPA is asking Dr. Savitz about the NTP monograph.
EPA changes mind, says they want to ask Dr. Savitz about the WHO study on fluoride.

EPA asks Savitz about the WHO's assessment of fluoride in seafood and how this would impact measuring fluoride.
Remember: Dr. Grandjean told me that the WHO has been infiltrated by the "Fluoride Lobby"

Read 45 tweets

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