Thread by @DBrozeLiveFree

Day 5 of the 2nd Phase of the Fluoride Lawsuit has begun!

Judge Chen is asking about exhibits.

Witness Dr. Ralph Barone is back on the stand with the EPA set to continue their cross-examination.

EPA to Dr. Barone: yesterday we talked about the 4 steps of Risk Evaluation, today we are going to talk about the next step, exposure assessment.

EPA is showing Barone a graphic which outlines the Exposure Assessment step.

Barone is breaking down the Intake Level of step of the Exposure Assessment step of the EPA's Risk Evaluation for chemicals.

Barone is discussing the "background" measurements that might be picked up at the Intake Level from other sources.

Judge Chen asks for some clarity about this process.

Fair warning: it's probably going to be another pretty technical day. I am doing my best to narrow down the finer points that you need to know. Thanks

EPA: Similar to what we saw with the hazard assessment there is a qualitative result, is that correct?

Barone: yes, it depends on the data set and the conditions of use. In some situations we have more data.

EPA now showing Barone a new graphic of the "Exposure Level Formula" which shows how EPA detects the Average Daily Dose. Looks like:

AVD = C x IR / BW

C is Concentration of Contaminant, IR is drinking water intake rate, and BW is body weight.

EPA: so I see you have the units under Average Daily Dose, what are they?

Barone: milligrams per kilograms per day

EPA has Barone explain the formula and if its accurately represented. Barone says this is the formula the EPA used on the first 10 TSCA assessments.

EPA: Let's turn to the Risk Characterization, the 3rd step in the Risk Evaluation.

Barone: For the Risk Characterization, there is the quantitative part and the qualitative part.

Barone: The qualitative evaluation looks at overall quality of the assessment and "degree of confidence in the estimates of risk and conclusions drawn". Looks at strengths, uncertainties, and assumptions.

EPA shows graphic relating to "Margin of Exposure" MOE and asks Barone to explain the process for determining the MOE. Formula:

MOE (Unitless) = Point of Departure mg/kg/day / Exposure Level mg/kg/day

Barone is explaining the formula and the process to Judge Chen in depth.

EPA: if the margin of exposure exceeds the benchmark, does the EPA move forward to determine risk?

Barone: no.

EPA: the lower the benchmark MOE the less uncertainty the agency has in the data?

Barone: That's correct, generally speaking, from a quantitative perspective, a lower benchmark MOE has lower uncertainty.

EPA: and the EPA's determination of what a particular benchmark MOE is is based on a review of the data for that particular chemical substance, correct?

Barone: it is, and based on the conditions of use.

EPA: has the EPA ever look to other benchmark MOE that it applied to other chemical substances when doing a benchmark MOE?

Barone: generally speaking no. We are not looking at points of departure for other chemicals.

The EPA is basically having Barone lay the case for the process which EPA used to determine risk for fluoride. EPA attorney is taking a long time to attempt to debunk the work previously established by @FluorideAction Attorney Michael Connett yesterday.

@FluorideAction EPA: before we move on to the last step of the Risk Evaluation process I want to show you some slides that FAN showed you yesterday and ask if they are consistent with the EPA risk evaluation process.

@FluorideAction EPA shows Barone a graphic used by FAN Attorney Connett and Barone is claiming that Connett misrepresented the process which EPA undergoes, by confusing certain steps.

@FluorideAction Barone continuing to state that plaintiffs misrepresented or confused various steps in the Risk Evaluation process.

@FluorideAction EPA pulls up another graphic from the plaintiffs and asks if it accurately represents how the EPA determines risk.

Barone: "I'm actually befuddled by this presentation.. I'm not sure what this is."

@FluorideAction EPA shows Barone another slide and asks the same question.

Barone: "this mention of inferred risk really throws me bc we are not inferring risk."

@FluorideAction EPA shows another slide from plaintiffs, showing exposure/ condition of use, with some red and blue bars, and MOE on the Y axis. EPA asks again if this accurately depicts how the EPA does risk evaluation under TSCA.

Barone says not appropriate comparison on the graph.

@FluorideAction Barone discusses the methods for risk evaluation related to lead, mercury, PCBs, etc.

@FluorideAction Barone: when we're talking about prenatal exposures, we are talking about growth within pregnancy, the growth of the mother. but the metabolism changes dramatically.

@FluorideAction Judge Chen has some questions for Barone.

Chen: unless it just appears, fluoride being detected in the urine, its indicating some type of relationship.

Barone: there is a relationship, but... with the biomarker urinary levels we are talking about something "less precise".

@FluorideAction Barone: its a challenge when looking at these exposures and determining the intake level and consistency of exposure.

Judge Chen: studies that show cross-sectional data, you see fluoride showing up in urine, is that something that can be used for modeling?

@FluorideAction Barone: its important, but again you want to be able to understand what is that "background level" of that compound in your biomarker. When you are looking at your POD, if you have a BMCL that is below background its hard to determine if its accurate.

@FluorideAction Judge Chen and Barone went back and forth for a few moments to get clarity. It genuinely seems like Judge Chen wants to understand the science.

@FluorideAction EPA now moves to have Barone describe the final step, in the 4 step process of Risk Evaluation as required under the TSCA.

@FluorideAction Barone: if we find an unreasonable risk we move immediately to rule making to see what we can do to reduce that risk.

@FluorideAction EPA: in previous testimony you mentioned that The National Academies of Sciences, Engineering, and Medicine (NASEM) had previously been involved in peer reviews. can you describe what NASEM has done?

Barone describes receiving "Critical feedback" from NASEM.

@FluorideAction EPA: one last question for you, pointing to a graphic shown by plaintiffs, "does the 89x and 27x are those factors..." FAN Connett objects for 2nd time. Judge agrees for overbroad.

EPA tries again, asks Barone if he knows what a Hazard Quotient is. Barone defines.

@FluorideAction Barone refers to the graphic shown by plaintiffs yesterday and says the 89x and 27x are not relevant to the risk evaluation. "It's not useful."

EPA: when EPA is doing a Risk Evaluation would they factors like this?

@FluorideAction Barone: "again, it makes no sense. These are apples and oranges, we don't do that.... This comparison here is not used and it doesn't make any sense."

EPA has no further questions. Judge Chen has questions for Barone.

@FluorideAction FAN Connett will pick up with a redirect of Dr. Barone.

@FluorideAction Connett to Barone: do you agree, as you testified under deposition, that fluoride should not be held to a higher standard compared to previous chemicals which EPA has acted on? Barone agrees.

Connett: and you testified that EPA does not "infer" risk? Barone agrees.

@FluorideAction Connett pulls up his deposition testimony. Reminds Barone that he took an oath to tell the truth and reads from Barone's deposition.

@FluorideAction Q: So EPA for this condition of use was prepared to extrapolate from high-dose animal studies to INFER that the lower doses that these workers were exposed to presents an unreasonable risk, right?

A: yes.

@FluorideAction Connett reads another Q and A from Barone's deposition where Barone previously agreed the EPA inferred conclusions based on available data.

@FluorideAction Connett reads one more final statement where Barone himself said EPA used inferences in their conclusions.

@FluorideAction Connett is grilling Barone about the "Benchmark Dose Technical Guidance", asking if he supports that guidance. Barone does.

Connett asks Barone what page does that discussion on human data begin. Barone gives a non answer, trys to explain, Connett asks him to answer.

@FluorideAction Connett is showing that the whole section of the BMDT Guidance relating to Human Data is only 1 page.

Barone says this is not accurate that there are other sections of the guidance relevant to human data.

@FluorideAction Connett reads directly from the guidance: "sometimes human toxicological data are reported in ways that are similar to the reporting of toxicological data for lab animals, and, in these cases, this guidance document would be applicable."

@FluorideAction Barone wiggles his way out of this by saying that the guidance has relevance to human data in other ways, disagrees with Connett's assessment.

@FluorideAction Connett: Nowhere in this document does EPA criticize Dr. Grandjean (previous witness) for not doing other tests (which Barone has mentioned are best practices), correct?

Barone agrees but says this document is not about impugning anyone else's research.

@FluorideAction Connett is establishing that the EPA itself uses research and methods conducted by Dr. Philippe Grandjean, and does not say anything about his methods being insufficient.

Barone: there are multiple approaches, there's not one approach.

@FluorideAction Connett ends his questions for Dr. Barone.

EPA comes back for a redirect. Asks to pull up Dr. Barone's deposition as well.

@FluorideAction EPA shows a question for Dr. Barone during deposition where he was asked if EPA inferred risk, he responded at the time that EPA "calculated risk".

Judge Chen orders court into recess for 15 minutes.