Thread by @DBrozeLiveFree

Day 5 of the 2nd phase of the #FluorideLawsuit resumes with FAN Connett calling Dr. Kathleen Thiessen as the next expert witness.

Thiessen's scientific background focuses on risk assessment.

Find out more about here here: fluoridealert.org/fan-tv/fluorid…

Connett asks Thiessen if she has done any work with the EPA, she confirms.

Connett asks Thiessen what specific chemicals she worked on, she mentioned she has worked on several different fluoride compounds.

Connett is showing the National Research Council's 2006 report which raised awareness about the neurotoxicant effects of fluoride.

Connett is establishing that Thiessen is the author of a large portion of the 2006 NRC review, and she also worked on the 2009 review.

Connett: does the research you did on the 2006 NRC review inform how you feel about fluoride in this case?

Thiessen: yes.

Connett: last week the court heard from Dr. Lanphear regarding hypothyroidism in the MIREC cohort. Did the NRC make any conclusions relevant to his research.

Thiessen: the NRC report described fluoride as a neurotoxicant chemical and an endocrine disruptor.

Connett is reading from the 2006 NRC report which deals with the impact on thyroid function.

"the recent decline in iodine intake in the US could contribute to increased toxicity of fluoride for some individuals"

Connett asks if Thiessen is familiar with iodine deficiency in pregnant women. She confirms this is accurate.

Connett asks Thiessen to confirm the states of Dr. Thayer, another witness, who stated that the animal data on fluoride is relevant to humans. Thiessen confirms.

Connett is now asking Thiessen about the comparison between the NTP report and the NRC 2006 review.

Connett is pulling up an exhibit, a page from the NTP draft, under Histopathlogy:

"the majority of low risk-of-bias studies found some histological changes in the brain of rats or mice treated with fluoride at concentrations at or below 20 ppm."

Connett asks if this statement is consistent with the findings of the NRC in 2006, Thiessen confirms.

Judge Chen asks for more details on what these "histopathological" changes are.

Thiessen describes how you can see physical changes, and changes to the cells of the brain.

Connett moves to discussion of the NTP meta analysis with Dr. Thiessen.

Connett shows her a forest plot: does the data that are displayed here for Bashash, 2017 and Green, 2019, tell us the whole story?

Thiessen: They do not.

Connett turns to page 19 of supplemental materials from the NTP report. Shows a highlighted section, asks what it shows.

Thiessen: they're showing the mean for the fluoride exposure for children.

Connett asks Thiessen to look at another column of the supplemental material, labeled Regression Slopes Meta-Analysis.

Connett asks Thiessen if the NTP ever plotted out the regression data.

Thiessen is describing Figure 19 from the supplemental material of the NTP report dealing with analysis of individual level fluoride exposure.

Thiessen: "the overall effect is a reduction of IQ by 1.81".

Judge Chen asks what level of exposure the IQ reduction is based on.

Thiessen explains the graph is showing a reduction in IQ by 1.81 points.

Connett is now showing another table from the NTP report that is highlighting the "mean-effects meta-analysis".

Connett is now showing one of the slides the EPA presented to Dr. Barone this morning relating to "Hazard Assessment". Connett wants to hear about Thiessen's weight of the evidence analysis.

Connett asks Thiessen if she has relied on animal data alone when making a hazard assessment. She says yes.

Connett asks if the NTP meta-analysis has also informed her analysis of hazards relating to fluoride.

Thiessen confirms that she does, says the NTP found association of lower IQ was found at doses below the recommend water fluoridation level.

Connett: Is there any reasonable doubt that neurotoxicity is a hazard of fluoride exposure?

Thiessen: neurotoxicity is a hazard of fluoride exposure, the evidence is abundant.

Connett: how would you describe NTP's communication of its conclusions about fluoride's toxicity vs the EPA's communication on its hazard assessment of fluoride?

Thiessen says the NTP communication was more transparent.

Connett asks several similar questions comparing the NTP to the EPA, Thiessen says the EPA has not been as open and transparent.

Connett is showing another exhibit to Thiessen from the EPA regarding "Weight of the Evidence" and "neurotoxicity".

Connett: of this 714 page only one paragraph was used to summarize the weight of the evidence for the toxicity of PCE? Thiessen confirms.

Connett: is there anything of relevance to the EPA's analysis of the toxicity of PCE and Methylene Chloride to the EPA's assessment of fluoride?

Thiessen confirms there is relevance.

Connett is now showing a specific page of the EPA's analysis for methylene chloride.

Thiessen again says the NTP's analyses are more robust and communicative than the EPA's own.

Connett goes back to the Hazard Assessment process previously discussed by witness Dr. Stanley Barone.

Connett wants to look at the confidence that EPA had in assessing PCE's toxicity.

Connett moves to the 2nd step in the Hazard Assessment, the Exposure Assessment.

Connett asks Thiessen about the process for determining how much water people drink on average.

Thiessen: we have pretty detailed information on many, if not all, of the subsets of the population.

Connett shows a slide from the EPA which shows 0.7 mg/L, Connett quotes from EPA opening statement, "The dose makes the poison."

Asks Thiessen if the figure is a dose, she says no its the concentration.

Connett is showing Thiessen another graph title "Fluoride Intake from community water (consumer only) Pregnant Women".

Connett: if we look at this from the vantage point of how much fluoride are people drinking in the water?

Thiessen explains the graph, says that people who are consuming less than the recommended level of .7 mg/L will still seem similar results at the lower consumption levels.

Judge Chen asks for some clarification on the previous slide.

Connett moves to new slide showing Water Intake of Pregnant women on one side, and then fluoride intake of pregnant women on the other which shows the "mean" fluoride intake for a pregnant woman.

Connett: Does the available data on the urinary fluoride levels data of pregnant women in fluoridated communities, that you have reviewed, confirm the data on these figures?

Thiessen says it does.

Connett: on Friday the EPA showed Dr. Grandjean the figure on the top right of this page which comes from the Green 2019 study. You also see this table from the Till 2018 study. Which of these studies provides more detailed data?

Thiessen says Till, 2018.

Connett asks which table she would prefer if she wanted to look at fluoride urinary levels?

Thiessen says the table from Till 2018.

Connett shows a table from Till 2018. What explains the difference between the women living in the fluoridated areas and non-fluoridated areas?

Thiessen: the primary difference is that one group is fluoridated and the other is not.

Thiessen further explains that the only thing that could explain the differences in the populations is water fluoridation.

Connett reads testimony from a Dr. Henry regarding the term "Fit for Purpose".

Connett now shows Thiessen the EPA Risk Characterization regulation. Read portions that states,

"EPA will: integrate the hazard and exposure assessments into quantitative and qualitative risk assessments"

Connett: how does Dr. Grandjean's analysis of urinary fluoride levels compare with what we just saw from the EPA?

Thiessen describes the data.

Connett: do we even need to get into the MOE, benchmark dose etc to know that fluoride is causing harm to mothers?

Thiessen: no.

Connett asked Thiessen to compare the work of Dr. Grandjean and whether it provides enough data to draw conclusions about fluoride's toxicity. She confirms that Dr. Grandjean's work does provide ample evidence of fluoride's harms.

Judge Chen has questions for Dr. Thiessen before Connett goes further.

Judge Chen: it begs the question we have been talking about, the POD and the MOE are based on the exposure intake level, and these are based on urinary fluoride levels in mother. I'd love your critique on how you can't rely on one or the other.

Judge Chen: so you take issue with the testimony that the EPA claimed, you say you can deal with urinary fluoride levels and not have to convert to what Dr. Barone described?

Thiessen: What we have with the MIREC study and others are urinary data, water concentration data etc

Judge Chen: but so far I havent see any kind of formula describing how urinary fluoride intake levels relate determining a risk evaluation.

Thiessen: the main thing is that urinary fluoride concentration is going to be related to fluoride intake of all levels.

Thiessen: urinary fluoride intake level is related to the overall fluoride intake.

Thiessen is stating that what Barone testified about earlier is not the only method for determining a risk evaluation.

Judge Chen: would it be your analysis that even you measure POD, MOE, etc that you can fairly infer that the primary source of the harm is a problem?

Thiessen says yes, explains the process for using fluoride intake via water fluoridation for determining a risk evaluation.

Dr. Thiessen and Judge Chen are still going back and forth, with Chen trying to understand the difference between the process described by Dr. Thiessen vs previous witness, Dr. Stanley Barone of the EPA.

Judge Chen: so the bottom line is you think its not improper to do an analysis based on urinary fluoride data as opposed to being based on the intake?

Thiessen: yes, you can do it, and if you have both data you can do both and it will be consistent.

Thiessen is explaining the process and goal of conducting a risk analysis.

Thiessen: with respect to drinking water, the effect is going to based on all fluoride intake, regardless of the source.

Thiessen: If you have some background exposure from tea or medicine, and you add exposure from drinking water, its only going to make the impact worse.

Thiessen: the indirect exposure to fluoridated water can come from the consumption of drinks and foods which are produced with fluoride.

Connett: is that phenomenon of people in non-fluoridated areas consuming fluoride in products, is that well documented?

Thiessen: yes.

Thiessen says its known as the "halo effect" and well documented.

Connett asks Thiessen if there are studies which confirm and show this effect/impact.

Thiessen says yes there is data available.

Connett asks if water fluoridation is a common practice in areas with larger populations. Thiessen agrees.

Connett: as part of your research on fluoride over the last 30 years have you become aware of the fluoridation status in most of our large metropolitan areas?

Thiessen confirms this is the case.

Connett: in the NTP meta-analysis, is there any data that would support the existence of an association between fluoride and lower levels of IQ at levels below 0.5?

Thiessen says yes.

Connett puls up the Board of Scientific Counselors Working Group report. Reads some quotes from the report.

NTP BSCSWG report:

"several of the highest quality studies showing lower IQs in children were done in optimally fluoridated (0.7 mg/L) areas."

Connett reads from the NTP report which states that "even in the optimally fluoridated cities... some urinary measurements exceeded" the levels at which harm is observed.

Connet says let's forget about the juice, soda, tea, pharmaceuticals and other exposures that mom's may be consuming, and just look at the urinary fluoride levels. Does this still present a risk?

Thiessen confirms.

Connett: when we are talking about the poisonous dose, we are not talking about the variables that make some people more vulnerable? Thiessen confirms.

Thiessen describes what variables might make an individual more susceptible to fluoride's harms, incl. those with kidney issues

Thiessen says this also includes poorer folks, people in lower socioeconomic status, who might not be getting enough calcium as well, that would be more greatly impacted by fluoride's effects.

Thiessen also says athletes and people who work out more are going to have higher water intake and potentially correlated to higher fluoride intake.

Connett asks Thiessen if there is any dispute in the scientific literature that individuals with kidney issues and nutrient deficiencies can be exacerbated by fluoride exposure?

Thiessen says no, confirms the risk.

Judge Chen has some more questions for Dr. Thiessen. Chen is asking about the calcium deficiency issue and how that might impact pregnant mothers.

Thiessen is explaining how fluoride can interfere with calcium intake.

Connett asks Thiessen if its true that people with kidney issues cannot detox from fluoride and thus it builds up in the body. Thiessen confirms.

Says she would expect fluoride's neurotoxic effects to impact those who can't release fluoride from the body.

Connett moves to focus on the Risk Determination step in the Risk Evaluation process.

Connett outlines the factors considered by the EPA relating to Exposure of Water Fluoridation. They include:

Duration / Frequency /Magnitude / Patterns / Number of People

Connett asks Thiessen to explain these factors.

Connett asks Thiessen about the difference between babies being exposed to fluoride by baby formula vs breastfeeding.

Connett: inf your review of EPA risk evaluations have you taken note of the number of people who have been exposed or risk of exposed? Thiessen says yes.

Connett shows her a slide looking at exposure to various toxins, including fluoride, and the number of people exposed.

Thiessen explains that this graph shows and says "roughly 300,000 infants are being exposed to fluoride" by the baby formula constituted with fluoridated water.

Judge Chen asks Thiessen where the graph came from, she says its sourced from CDC data about formula-fed babies.

Connett shows a statement from the EPA, "the neonatal stage is a period of rapid development and nervous system growth" that is a critical period.

Connett shows a table summary of EPA's final risk evaluation of chronic non-cancer risks. Connett is asking Thiessen to confirm that the EPA has previously acted on other potentially toxic chemicals at levels below the levels where harm begins.

Connett showing another risk evaluation where the EPA used the lowest observed adverse effect level (LOAEL) to determine risk.

Connett is working to establish that EPA has indeed acted in other cases where a risk was detected at levels below the average fluoride exposure level.

Connett: Last Dr. Thiessen, a question on this isue of uncertainty, when you, as a risk assessment scientist, have a plausible finding and an implausible finding do you give more weight to one?

Thiessen says yes, the plausible finding.

Connett has no further questions. Court in recess for another break.

Will be back for final segment with EPA cross examining Dr. Thiessen.