Thread by @DBrozeLiveFree

We are back for the 2nd round of Day 2 of phase 2 of the #FluorideLawsuit

The EPA is going to cross examine Dr. Bruce Lanphear.

Judge Chen is asking both sides about the studies that been submitted and questions about hearsay.

Judge Chen is asking Dr. Bruce Lanphear about the linear curved response, asks what was the low-end of that dose. Some back and forth with Lanphear.

Lanphear wants to turn off the fan in front of him. Judge Chen makes a joke about "linear response".

EPA begins cross.

EPA: the first author of the Green study was a PhD student when publishing?

Lanphear: she may have been in the doctoral program but not completed her masters.

Discussing this study, Hall, 2023:

Fluoride exposure and hypothyroidism in a Canadian pregnancy cohort

pubmed.ncbi.nlm.nih.gov/36764861/

EPA: you were trying to evaluate whether maternal exposure lead to hypothyroidism in children?

Lanphear confirms. EPA begins to outline the 3 different methods used in the study.

EPA: Generally speaking, a study based on urinary markers provides a more accurate picture than community level drinking concentration?

Lanphear: I dont know that I would frame it like that. It doesnt always provide a better picture.

Lanphear continues to explain the differences in methods of exposure.

EPA: I just want to clarify 1 thing, the urine samples used in Hall in 2023 came from Goodman study in 2018?

Lanphear: correct.

EPA: due to the larger sample size, the urinary figure is likely more representative of that study populations urinary figure levels than the creatinine adjusted levels?

FAN objects, judge over rules.

Lanphear: That in general would be true, but its also possible, lets say I went to 1 neighborhood and only went to a 1 block radius that would be less representative than a random sample. But as a general rule, a larger sample size is better.

EPA continues to outline the 3 different methods Lanphear used in previous studies.

EPA says how Lanphear and team looked at water fluoridation levels in different areas, matching that with women by their post code, and then taking an average.

EPA: from a thyroid standpoint, you categorized women into 3 groups. Women who were classified by hypothyroid were determined by 2 methods. One method was self-reporting from a woman. The other method was to measure thyroid hormones, TSH and FT4

Lanphear is explaining how when studying fluoride intake and primary hypothyroidism they found an association.

EPA: you did find a connection between water fluoridation and hypothyroidism, but not subclinical hypothyroidism, correct?

Lanphear: correct.

EPA is arguing that the studies conducted by Lanphear only found a statistcally significant association between water fluoridation concentration and risk of primary hypothyroidism.

EPA says the study only looked at a woman's exposure during pregnancy and did not take any prepregnancy measurements. Lanphear confirms.

EPA brings up the self-reporting of hypothyroidism by pregnant women. EPA says the majority of the women were self reporting.

EPA says some of the self reported women might have traveled during pregnancy and consumed fluoride elsewhere. EPA says Hall, 2023, also didnt account for how long ago the self-reported women were diagnosed with hypothyroidism, even though they account for 75% of the subjects.

EPA: based on the studies available today, the connection between fluoride exposure and hypothyroidism is mixed at best, correct?

Lanphear: no, I think its quite consistent. Thats what the NRC 2006 study found and based on my reading of the data I think its consistent.

EPA wants to show a document, FAN objects, Judge Chen responds and says EPA must show the plaintiffs the info. EPA clarifies info is not in deposition, FAN withdraws objection, EPA continues.

EPA brings up page 2 of Hall, 2023, looking at paragraph 3 where it states that studies on hypothyroidism are "mixed".

EPA: Hall, 2023, did not find a statistically significant association between maternal primary hypothyroidism and lower IQ scores in girls and boys combined, correct?

Lanphear is refreshing his memory of the study...

Lanphear: that is correct.

EPA asks similar question about girls, Lanphear confirms they did not find an association.

EPA asks about study findings related to boys IQ. Lanphear confirms they did find an association.

EPA: out of the 28 mothers with primary hypothyroidism, only 13 had boys, correct?

Lanphear, checks notes, let's say yes.

EPA: so the statistically significant association between maternal primary hypothyroidism and lower IQ scores in boys was based on 13 boys, correct?

Lanphear: yes.

Judge Chen asks Lanphear to explain the small sample size.

Lanphear says they can find a statistically significant association even with a small sample size if the impact is high enough.

Judge Chen affirms and says you have more confidence bc you factor in the sample size.

EPA: Hall, 2023, did not find any statistically significant association between maternal subclinical hypothyroidism and lower child IQ, correct?

Lanphear: that's correct.

EPA: in Hall, 2023, you were examining if hypothyroidism helps explains the causal relationship between fluoride and lower IQ in children.

Lanphear: correct.

EPA: You found that primary hypothyroidism in the mother did not significantly explain lower IQ in children?

Lanphear: that's correct.

EPA: the women in the MIREC report are more likely to be affluent and more likely to use pre-natal vitamins, correct? Lanphear confirms.

EPA says this could effect the outcome of the study and asks Lanphear to confirm tha the MIREC study has limited impact on US population.

Lanphear confirms. EPA says no further questions.

FAN Connett picks up for redirect.

Connett: is there any reason to believe women living in fluoridated areas would have lived in these areas shorter or longer periods of time vs non fluoridated women? EPA objects, Judge Chen allows Dr. Lanphear to state his opinion.

Lanphear: if a community is fluoridated, it tends to stay that way.

Judge Chen: do you know what percentage of communities live in fluoridated areas vs non-fluoridated areas in Canada?

Lanphear: says in Canada its about 30% fluoridated communities & about 70% non-fluoridated

Connett asks Dr Lanphear about Dr. Hu's testimony yesterday regarding noise vs signal.

Connett ends questioning. EPA has no further questions for witness.

Court recesses for a 10 minute break.