Breast Milk and PFASs - Part 10

Back to the real focus.

Remember why the Breastfeeding Paper authors focused on PFASs as a health concern.

...a major concern is that PFAS exposure may undermine childhood immunization programs.

Remember the paper they cited to substantiate that concern; the Antibody Paper.

Now remember what the Antibody Paper authors said about the maternal serum concentration at week 32 of pregnancy.

The prenatal exposure level, as indicated by the mother’s serum concentration during pregnancy, was less clearly associated with the antibody outcomes.

The Antibody Paper tells us this:

In a structural equation model, a 2-fold greater concentration of major PFCs in child serum was associated with a difference of −49% (95% CI, −67% to −23%) in the overall antibody concentration.

This is based on looking at the PFASs at age 5 and 7 years and comparing them to the antibody concentrations found.  Doubling the amount of PFASs was shown by their model to decrease the overall antibody concentration by about 50%.

Let's look at the reality of that population of 656 in the study.  After 5 years, 532 children showed this level of antibody concentrations prebooster:

Source: Antibody Paper - Table 1 excerpt

For tetanus, 75% of the values for the 532 children were above 0.1 IU/mL which we are told:

...is considered an important indicator of protection in accordance with the public health rationale for routine vaccinations.

75% of all these children had antibody concentrations above the protective level for tetanus and almost 75% of these children had antibody concentrations above the protective level for diphtheria.

That is 75% for of the 532 children from the Faroe Islands who were specifically chosen for this study because:

frequent intake of marine food is associated with increased exposures to PFCs

If 75% of these kids with a suspected increased exposure to PFASs for both them and the mother are protected (above 0.1 IU/mL), then what would we expect the antibody concentrations to be in a child born to a mother in San Antonio, Texas?

Even if the Antibody Paper's model is true, and we see a 50% reduction in antibodies with a 2-fold increase in exposure to PFASs, Does breastfeeding there in the Faroe Islands or in San Antonio, Texas produce a 2-fold increase in PFASs for the child?

Does 6 months worth of breastfeeding produce a noticeable increase in PFASs whereby the antibodies would decrease below the 0.1 IU/mL protection level?  Is there a statistical difference between children who are breastfed falling below the 0.1 IU/mL protection level compared to children who were not breastfed.

That's the question they should have asked and that's the statistics they should have reported.

Armed with that, one could then decide to forgo breastfeeding benefits in order to reduce the chance of their child falling below the antibody protective level of 0.1 IU/mL.

Every time I read the Breastfeeding Paper I came up with more" huh?"  Things I needed to know were left out.  When I realized just how how off the mother's serum concentrations were from the population of mothers they were pulled from, the paper's findings became less and less credible.

Here is what I know from the Breastfeeding Paper:

They have 81 mothers and those 81 mothers have 81 children.  From this 81 they were able to get data.

Ignoring the mother's serum levels reported for PFOS, we see that 68 children from these 81 mothers had their blood tested at age 11 months.  We are shown data that tells us how much PFOS were in the kids at 11 months.

We also have data for PFOS in these kids at 18 months.  We are not told if these are the same kids from testing at 11 months, or a new set of the kids from the 81 tested at 18 months.

We are told this:

Figure 1 shows the trajectories of the five major PFAS for the 12 children with complete observations from all examinations.

What I understand this to mean is that only 12 children of the 80 mothers had blood sampled for PFOS at 11 months and 18 months.

We are told that the amount of time some of these 81 children were exclusively breastfed was 4.5 months.  We are told that some of these 81 children were partially breastfed for 4 months, and that some of these 81 children were only breastfed for one month or less.

What we are not told is how many of the 73 women of the 81 who replied to the question on breastfeeding fall into each of those three groups.

What were are not told is' of the 73 women of the 81 who replied to the question on breastfeeding, what the concentration of PFOS for each of these three groups.

What we are instead given is a graph:

Source: Breastfeeding Paper - Figure 1

We are told by the authors of the Breastfeeding Paper this:

The child with the lowest concentrations (blue dotted line) was not breastfed at all, whereas the child with the highest PFOS concentration (black solid line) was breastfed exclusively in 6 months and was partially breastfed during the following 5 months.

What we are not told - and I have looked and looked to make sure I did not overlook it - is what the other lines and colors represent.  That bit of information was left out.  Oops!

Okay, you got 12 kids with complete data.  One of them was breastfed exclusively and the other was not.  Does the blue dotted line represent the population of those who do not breastfeed?  Does the black solid line represent the population that exclusively breastfeeds?

What do the other lines show?

Here is what I want to know:

1. What was the concentration of PFOS at 11 months for the kids who were exclusively breastfed?
2. What was the concentration of PFOS at 11 months for the kids who were not breastfed?
3. What was the concentration of PFOS at 18 months for the kids who were exclusively breastfed?
4. What was the concentration of PFOS at 18 months for the kids who were not breastfed?

With that data, one could see if there is a statistical difference between the two groups.  Why was that not done?  Why focus on showing us a graph of 12 of them and leave out the explanation of the data for 10 of those 12?

I am unwilling to look at two children and say that their PFOS values represent the two groups.  In particular, the PFOS values for the not breastfed kid - the blue dotted line - is way below the lowest IQR reported for 68 of the kids tested at 11 months.

So there you have it.  I have beat this dead horse as much as I can.

If you are going to forgo the benefits of breastfeeding because you are concerned about passing on PFASs to your baby, then you would be making a big mistake if the reason for doing so is based on this paper's findings.

Thanks for reading.

Breast Milk and PFASs - Part 9

Continuing on from my last post...

In order for me to be correct in what I am about to show, my observation of the Breastfeeding Paper data must show that a geometric mean and IQR they used in their model is what I am seeing and was used to produce this statement:

The duration of exclusive breastfeeding was associated with increases of most PFAS concentrations by up to 30% per month, with lower increases during partial breast-feeding.

According to the Breastfeeding Paper's authors, the serum concentration for PFOS for the 80 mothers had a geometric mean of 6.0 ng/mL and an IQR of 5.2, 7.2.  This, if my understanding of an IQR is correct, means that 75% of the PFOS found in these 80 mothers was below 7.2 ng/mL.

Source: Breastfeeding Paper - Table 1 excerpt

Those 80 mothers were pulled from the 656 mothers with serum concentrations of PFOS collected at week 32 of pregnancy.

Here is where my angst is coming from.  Let's look at the data presented in the Antibody Paper for the 656 mothers from which those 80 mothers were pulled from:

Source: Antibody Paper

In particular, lets just look at the serum concentration for PFASs found in the 656 mothers at week 32 of pregnancy.

Source: Antibody Paper - Table 2 excerpt

Notice something?  The Antibody Paper from which the data came from tells us that the PFOS in the 656 mothers tested have a geometric mean of 27.3 ng/ml.

Something ain't right here.  How can these 80 mothers - pulled from the 656 mothers - have a PFOS serum concentration that far below the lower IQR of 23.2 ng/mL?

75% of the 80 mothers have a PFOS concentration in the lowest 25% of the 656 mothers?

That's...that's...highly unlikely!

In fact, looking at their data in Table 1, almost all of the four PFASs upper IQR value for the 80 women are below the lowest IQR value reported for the 656 women they came from.

That cannot be correct.  The odds of 80 mothers being so drastically different from the population they came from would, without benefit of a calculation, be exceptionally low, I contend that this serum data from the mothers is in error.

In contrast, the PFASs reported for the children at 11 months and 18 months fall very close to the IQR range reported for the mother's 32 week pregnancy concentration in the Antibody Paper.

Source: Breastfeeding Paper - Table 1 excerpt

At 5 years (60 months) the PFASs of these 80 kids align very close to the results report for the 656 in the Antibody Paper.

Source: Breastfeeding Paper - Table 1 excerpt

Source: Antibody Paper - Table 2 excerpt

I contend - and I could be wrong here - that the values they used in their prediction model for 0 month - the serum concentration of PFASs at 32 weeks of pregnancy - for these 80 mothers is incorrect.  I cannot accept the ng/mL values for 0 month that they report in Table 1.  I cannot accept it based on what is reported for the overall population for the mothers in Table 2 of the Antibody Paper which is where these 80 mothers came from.

If the glove don't fit....

So...the Breastfeeding Papers claims to show that:

The duration of exclusive breastfeeding was associated with increases of most PFAS concentrations by up to 30% per month, with lower increases during partial breast-feeding.

But for that to be true, the actual serum level of the child would need to be known at 0 month.  If you are going to assume that the serum level of the mother at 32 weeks is that value, then that value must be correct for your model to be sound.

Here is what I see - and why it has taken me a while to write these last posts.

I see that 328 women from the Antibody Paper had blood serum concentrations of PFOS between 23.2 and 33.1.  That's a range of 9.9 between 328 women.

According to the Breastfeeding Paper, 60 of the women - pulled from the Antibody Paper's 656 women - had PFOS concentrations 20.1 less than the lowest value seen in 492 (75%) of the women tested.

That cannot be correct.

Next post: Part 10

Breast Milk and PFASs - Part 8

The posting for a conclusion to all of this is taking me longer than I anticipated.  I'll explain why in a bit if you keep reading.

Focus: Should a new mother forgo the benefits of breastfeeding based on the findings based on the findings present in this paper:

Breastfeeding as an Exposure Pathway for Perfluorinated Alkylates

This paper made my Google Newsfeed show me news articles with titles such as this:

Breast milk may be tainted with toxic chemicals – says new research

The authors of this paper, which from here on I will call the "Breastfeeding Paper," tell us in the abstract that:

The duration of exclusive breastfeeding was associated with increases of most PFAS concentrations by up to 30% per month, with lower increases during partial breast-feeding.

That "30% per month" statement is the result of their modeling:

We first included only the three concentrations obtained at birth and at age 11 and 18 months. The model was estimated using a linear mixed model with breastfeeding variables included as covariates.

What is important to understand at this point, is that the amount of PFASs in the breast milk was never measured:

However, neither the newborn baby’s PFAS concentrations nor the concentrations in milk were measured in this study, which instead relied on the maternal serum concentrations measured at a specified point during pregnancy/

The concentration used in their model for month 0 is this:

Serum-PFAS concentrations at birth were calculated from maternal concentrations.

Month 0 is critical for their model, which uses three points for their prediction, 0 month, 11 months, and 18 months.  This is where the statement "increases of most PFAS concentrations by up to 30% per month" comes from and is shown in their prediction graphs.

Source: Breastfeeding Paper

Here is where I started to have troubles and why it is taking me a while to get these posts out.

I need to make sure that what I see is correct before I put it out for the whole world to see.  I understand I could be wrong in anything I post.  I admit that, and I will correct my mistakes if they are pointed out.  I want to be objective and fair.

I am trying to have my facts straight and my understanding of what I see as sound as I can get it before I post it for all the world to see.  So here goes.  If I am mistaken from what I post, I will apologize and I will correct it.

Let's get back to month 0 in their model.

Serum-PFAS concentrations at birth were calculated from maternal concentrations.

Where did this data come from?

A birth cohort of 656 children born in the Faroe Islands was formed during 1997−2000 and followed prospectively. A serum sample and informed consent were obtained at week 32 of pregnancy.

Hmmmm.  That's the same cohort used in the paper they cite for "vulnerability of the immune system during early development":

Serum Vaccine Antibody Concentrations in Children Exposed to Perfluorinated Compounds.

From this point on I will call this the "Antibody Paper."

The Breastfeeding Paper's authors used the same data from the same people used in the Antibody Paper.

The Breastfeeding Paper authors took from those 656 children studied this data:

During a 12-month period of the follow-up period, a subgroup of mothers was invited to bring in their children for an examination and blood tests at ages 11 months and 18 months

Remember this:

The prenatal exposure was assessed from the mother’s serum-PFAS concentrations at pregnancy week 32

The data in the Breastfeeding Paper came from 81 mothers of the cohort of 656 used in the Antibody Paper.

Can we agree that the Mother's serum PFAS concentration detected in the Antibody Paper are what is being used in the Breastfeeding Paper for month 0?  There was no additional analysis performed by the Breastfeeding Paper's authors.  The 81 mothers used in the Breastfeeding Paper were part of the 656 mothers used in the Antibody Paper.

I am pretty sure I am correct on this and I am not missing something or misreading their paper.

Here is where I started to have my doubts on the model's findings they reported.  I know better than to accept the conclusion of a paper without first looking at the data.  Statistics and squishy wording are used a lot in peer reviewed journal papers to support or elude to a finding of positive or negative outcomes.

With this in mind, what does their data say?

Let's look at Table 1 in the Breastfeeding Paper:

Source: Breastfeeding Paper

Let's look at the data for "0 month: aka: birth - in particular the serum concentrations for 80 mothers who had their serum concentrations for PFAS's measured at pregnancy week 32.

Source: Breastfeeding Paper - Excerpt from Table 1

We now need to agree that the serum concentration in Table 1 is in ng/mL.  Which means that for 80 mothers pulled from the 656 mothers used in the Antibody Paper, these 80 mothers had a geometric mean of 6.0 ng/mL of PFOS.

The authors of this paper - see note at bottom of Table 1 - use "median" for "geometric mean."  They are not the same, but that point is for another paper someone else can write about statistics.

What is important is that we agree that the Breastfeeding Paper authors are telling us that the geometric mean for PFOS in these 80 mothers was 6.0 ng/mL.

We need to also agree that the IQR reported - 5.2 and 7.2 - means that 75% of the PFOS concentrations found in these 80 mothers were no higher than 7.2 ng/mL

Source

 Still with me?

According to the Breastfeeding Paper's authors, the serum concentration for PFOS used in their model for each of the 80 mothers had a geometric mean of 6.0 ng/mL and an IQR of 5.2, 7.2 which means 75% of the PFOS found in these 80 mothers were below 7.2 ng/mL.

Those 80 mothers were pulled from the 656 mothers with serum concentrations of PFOS collected at week 32 of pregnancy in the Antibody Paper.

In order for me to be correct in what I am about to show, my observation of their data must show that a geometric mean of 6.0 ng/mL and an IQR of 5.2, 7.2 was used in their model that produced a result that allowed them to make this statement:

The duration of exclusive breastfeeding was associated with increases of most PFAS concentrations by up to 30% per month, with lower increases during partial breast-feeding.

Next post: Part 9

Breast Milk and PFASs - Part 7

In their paper:

Breastfeeding as an Exposure Pathway for Perfluorinated Alkylates

The authors state:

Adverse effects of PFASs reported in children with similar serum-PFAS concentrations include immunotoxicity, as revealed by decreased antibody concentrations toward childhood vaccines and increased frequency of common infections.

and...

Our results show that four of the major PFASs tended to increase substantially during the breast-feeding period, thereby suggesting that human milk is a main source of exposure during infancy.

This is where the focus needs to be.  Should a new mom be concerned about this?  The news articles generated from the publication of this paper all screamed about toxic chemicals in breast milk and how they are passed on to your baby.

Here's the thing though.  This paper only looks at PFASs as a toxic chemical in breast milk. The concern therefore will only be for PFASs being present and passed on to the baby through breast feeding.  If they are present, the concern the authors tell us is because they could decrease antibody concentrations and increase the frequency of common infections.

If they are present...decrease antibodies for tetanus and diphtheria, and more common colds and gastroenteritis.

If they are present, that is what the author's of the paper contend could be the negative health outcomes.

If a new mom, because she read or was told about the news stories that resulted from this paper, chooses not to breastfeed because of this concern, then there will be zero benefits her baby receives.

Zero benefits if breastfeeding is not provided to the baby.

Zero benefits because of this paper.

The "toxic" chemical in the news stories is for PFASs.  The health concerns they tell us could result from an increase in exposure are decrease antibodies for tetanus and diphtheria, and more common colds and gastroenteritis.

What's your point Bowman?  You are beating a dead horse again.

Yeah...But that understanding is important here.  Are all mothers who want to breastfeed their baby going to put their baby at risk for decreased antibodies for tetanus and diphtheria, and more common colds and gastroenteritis.

Does this paper provide enough support for a new mother to give up breastfeeding to protect their baby from the harm of PFAS?

We can take the claim of an increase in common colds and gastroenteritis off the table of potential negative health outcomes.  It is not supported (see previous post).  This leaves the decrease in antibodies for tetanus and diphtheria.

The paper they cite; "Serum Vaccine Antibody Concentrations in Children Exposed to Perfluorinated Compounds," tells us this:

These results indicate that PFC exposures at commonly prevalent serum concentrations are associated with lower antibody responses to childhood immunizations and an increased risk of antibody concentrations below the level needed to provide long-term protection.

However...

The prenatal exposure level, as indicated by the mother’s serum concentration during pregnancy, was less clearly associated with the antibody outcomes.

That's important here.  What these guys say in their paper - the paper cited to support the negative health outcome of "decreased antibody concentrations toward childhood vaccines" - is that the mother's serum level of PFASs had a weak association with the antibody outcomes seen at 5 and 7 years.

So?

So if the mother's serum concentration during pregnancy is "less clearly associated with the antibody outcomes" then the adverse effects stated by the authors in their paper "Breastfeeding as an Exposure Pathway for Perfluorinated Alkylates" cannot support the negative health outcome of a decrease in antibodies for tetanus and diphtheria.

How can you say that Bowman?

Because these guys used the same cohort as the guys they cited.  Its the same data, the same serum concentrations, the same kids, the same mothers.

If the original paper "Serum Vaccine Antibody Concentrations in Children Exposed to Perfluorinated Compounds" tells us they found that "the mother’s serum concentration during pregnancy, was less clearly associated with the antibody outcomes" then the paper titled "Breastfeeding as an Exposure Pathway for Perfluorinated Alkylates" should not elude to negative health outcomes from breastfeeding and PFASs.

Here is what they state in the Breastfeeding paper:

Adverse effects of PFASs reported in children with similar serum-PFAS concentrations include immunotoxicity, as revealed by decreased antibody concentrations toward childhood vaccines and increased frequency of common infections.

That's in their paper.  This is too:

Given the importance of postnatal development of acquired immune function, the shape of the serum concentration profile may be important for PFAS-associated immune deficits.

Based on what? The guys they cited, the guys who provided the data they used, tell us this:

The prenatal exposure level, as indicated by the mother’s serum concentration during pregnancy, was less clearly associated with the antibody outcomes.

So if the prenatal exposure level in the mother is less clearly associated with the antibody outcomes, should a new mother forgo breastfeeding to decrease the risk of decreasing antibody outcomes?

No.  Why? Because the prenatal exposure level, as indicated by the mother’s serum concentration during pregnancy, was less clearly associated with the antibody outcomes.

But...that's the mother's serum exposure before the baby is born.  The paper tells us that "human milk is a main source of exposure during infancy."

Work with me here...

If a baby is exclusively breastfed for six months, then the major source of PFASs would be through the breast milk.  So the higher the serum concentration of PFAs before birth in the mother, the more PFASs transferred to the baby.

So...if  "the mother’s serum concentration during pregnancy, was less clearly associated with the antibody outcomes" at 5 and 7 years then breastfeeding, and it is the decrease in antibodies found at 5 and 7 years that supports this statement:

Adverse effects of PFASs reported in children with similar serum-PFAS concentrations include immunotoxicity, as revealed by decreased antibody concentrations toward childhood vaccines...

 Breastfeeding is therefore not shown to be contributing to an increased risk of antibody outcomes.

How can I state that when we are talking about breastfeeding and not the mother's serum concentration?

The authors of "Breastfeeding as an Exposure Pathway for Perfluorinated Alkylates" built a model using data from "Serum Vaccine Antibody Concentrations in Children Exposed to Perfluorinated Compounds"

This model, they contend, shows this:

The duration of exclusive breastfeeding was associated with increases of most PFAS concentrations by up to 30% per month, with lower increases during partial breast-feeding.

They then tells us this:

After cessation of breastfeeding, all serum concentrations decreased.

This is where we need to look at the data they used to make their model.  This mothers serum concentration becomes really important here.  This is where I had to pause and reflect when I read this:

As we used log scale transformations of PFAS concentrations, the higher milk concentrations from mothers with elevated serum concentrations were included in the model by default. However, neither the newborn baby’s PFAS concentrations nor the concentrations in milk were measured in this study, which instead relied on the maternal serum concentrations measured at a specified point during pregnancy.

Now, one more time...

The prenatal exposure level, as indicated by the mother’s serum concentration during pregnancy, was less clearly associated with the antibody outcomes.

Next post: Part 8

Breast Milk and PFASs - Part 6

In their paper "Breastfeeding as an Exposure Pathway for Perfluorinated Alkylates," the authors tell us that:

exposure via human milk could therefore lead to elevated serum concentrations in breastfed infants.

 This, they tell us, is a concern because:

Adverse effects of PFASs reported in children with similar serum-PFAS concentrations include immunotoxicity, as revealed by decreased antibody concentrations toward childhood vaccines and increased frequency of common infections.

I believe I showed in my previous post that there is nothing to support the "increased frequency of common infections."  This leaves us with the "decreased antibody concentrations toward childhood vaccines" concern.

The authors cite the paper called "Serum Vaccine Antibody Concentrations in Children Exposed to Perfluorinated Compounds"  In my last post I looked at this data, and ended the post with this:

Let's ignore that.  Let's assume that their negative numbers shown in Table 3 actually show that exposure results in a decrease of antibody concentration.  Let's forget about the values the model calculated with a 2-fold exposure, and just look at what they found.

Time out!

I write these posts in real time.  I start with a question and I try to answer it.  I am not sure if my thinking at the beginning will be changed at the end.  I am not sure what rabbit holes I will go down as I try to support my position.

This series of posts has been a challenge towards the end.  In my last post I looked at the data from the paper they cited to support the concern that:

...exposure via human milk could therefore lead to elevated serum concentrations in breastfed infants.

I am trying to support my position that breastfeeding in the first six months - based on WHOs recommendations - has better health outcomes for the baby then forgoing breastfeeding because "Breastfeeding can expose babies to toxic chemicals" as the news articles so quickly reported based on their paper's claim.

So it comes down to this:

Should a woman forgo breastfeeding based on this paper's contention that "exposure via human milk could therefore lead to elevated serum concentrations in breastfed infants?"

1. If that statement is true, it is true for one particular group of chemicals; PFASs.

and....

2. If there is elevated serum concentrations of PFASs in the baby who was breastfed, will those elevated levels of PFASs cause a negative health outcome?

and...

3. If those PFASs now in the baby will cause a negative health outcome for the baby, is that negative health outcome greater than the benefits of breastfeeding?

I am trying to understand what their data shows.  I am having a very difficult time understanding it.

Question 2 is the key to this.  Their paper claims that breastfeeding "could therefore lead to elevated serum concentrations."  This claim needs to be supported by data, and, if true, the elevated serum concentrations of PFASs must present a negative health outcome.

So here is where I am having trouble with this.  I need to know if PFASs are transmitted in breast milk, and if they are, is the baby impacted in a negative way greater than a baby who was not breastfed?

Which brings me to this point.  Their data does not make sense to me.  This is a a peer reviewed paper and has a "Harvard" affiliation.  All of this is making me question myself.  I must not be seeing this correctly.

I have read, reread, and re-reread, and re-re-reread these papers many times.  The more I read them the more convinced I am that I must be missing something or am too much a novice to understand them.

Surely they could not have left this information out intentionally or accidentally.  The peer review would have caught it.  Its not there, things are missing, graphs are not explained....am I really seeing what I think I am seeing or am I missing it because I am below some level of understanding needed to review this paper?

Then I remember that its not me that has to support their findings, its them.  Did they?

Next post: Part 7

Breast Milk and PFASs - Part 5

Let's look at the author's statement in their paper "Breastfeeding as an Exposure Pathway for Perfluorinated Alkylates":

a major concern [because] PFAS exposure may undermine childhood immunization programs.

Is it?  They cite two papers that make this claim:

1. Pre-natal exposure to perfluoroalkyl substances may be associated with altered vaccine antibody levels and immune-related health outcomes in early childhood
2. Serum Vaccine Antibody Concentrations in Children Exposed to Perfluorinated Compounds

Let's look at the first one.

Most clearly, a 2-fold increase in PFOS exposure was associated with a difference in [antidiphtheria] antibody concentration of -39% (95% CI, -55% to -17%) at age 5 years before the booster.

Thus, a 2-fold increase in PFOA exposure was associated with differences of -36% (95% CI, -52% to -14%) and -25% (95% CI, -43% to -2%) for tetanus and diphtheria, respectively.  

Okay...assuming that to be true, now we are looking at something that may be significant, not just statistically significant.

Why would this drop in antibody concentration be of a concern?

PFC exposures at commonly prevalent serum concentrations are associated with lower antibody responses to childhood immunizations and an increased risk of antibody concentrations below the level needed to provide long-term protection.

Okay...again, assuming their data does actually show a decrease, this is a concern.

What did the second paper show?

Based on the β -values, the strength of the association between rubella antibody-levels and PFAS concentrations were PFNA >PFOA >PFHxS >PFOS. No significant associations were found between the concentrations of PFAS and vaccine antibody levels to the other vaccines.

Though not in complete agreement, there is a case to be made that PFAS concentrations in serum blood impact antibody levels.

The first paper supports its findings stating:

Our findings are supported by several. though not all, experimental studies in rodents, in which adverse effects of PFOS on humoral immune function were observed at serum concentrations similar to those reported in the present study and at levels prevalent in the United States.

Why this lowered antibody levels might be considered a "major concern" is based on this:

An antibody concentration greater than 0.1 IU/mL is considered an important indicator of protection in accordance with the public health rationale for routine vaccinations. Prenatal and postnatal PFOS exposures, as well as postnatal PFOA exposure, were associated with increased odds of antibody concentrations below the protective level.

 Let's look at the data for the 1st paper cited.

Most clearly, a 2-fold increase in PFOS exposure was associated with a difference in [antidiphtheria] antibody concentration of -39% (95% CI, -55% to -17%) at age 5 years before the booster.

That's a result based on a model they generated:

Structural equation models were generated to determine the joint associations of PFCs with the overall antibody concentrations.

And those models were designed from the statistical data they calculated:

Multiple regression analyses with covariate adjustment showed that prenatal exposures to both PFOS and PFOA, as indicated by the maternal serum concentrations, were negatively associated with antidiphtheria antibody concentrations (TABLE 3)

 Let's look at Table 3:

See those 95% Confidence Intervals (CIa)? Here is what they show:

Confidence intervals provide an ‘estimate interval’, that is, a range of values around the point estimate within which the true value can be expected to fall.

In statistics, this statement is true:

The wider the confidence interval is, the more variability in the sample, and the less precise the point estimate.

The authors in the cited paper claim that "both PFOS and PFOA, as indicated by the maternal serum concentrations, were negatively associated with antidiphtheria antibody concentrations."

The CIs for these percent difference result range from a negative percentage to a positive percentage.

This means that although they report a negative number (a decrease in the percentage of antibodies when compared to a population that was not exposed), the true value falls between that range.  It could be any number between -31.9 and +18.7.

This range - from negative to positive - is seen in the majority of results in Table 3.  It appears that the authors ignored that. and focused on the mean value - a negative number - that the statistics program spat out.

This range, at least to me, makes the statement of a negative difference in antibody concentrations found, questionable.  Its too variable to say the mean is representative of the population at large.

Let's ignore that.  Let's assume that their negative numbers shown in Table 3 actually show that exposure results in a decrease of antibody concentration.  Let's forget about the values the model calculated with a 2-fold exposure, and just look at what they found.

Next Post" Part 6

Note: This was written earlier than post date.  My next post will explain why.

Breast Milk and PFASs - Part 4

This fire,,,:

...was started from this paper...:

...that states the following...:

Concentrations of PFOS and PFOA in breast milk are generally between 20 and 100 ng/L,4 and a daily milk intake of about 125 mL/kg body weight5 could easily contribute about 6 ng/kg per day or a total of 1 μg/kg for the recommended 6 months of breast-feeding.

...which they say is a concern because...:

exposure via human milk could therefore lead to elevated serum concentrations in breastfed infants.

... and that it also is...:

a major concern [because] PFAS exposure may undermine childhood immunization programs.

...as well as...:

 increased frequency of common infections

...which then leads all the news organizations and advocates to conclude:

There is nothing to support the statement of "increased frequency of common infections,"  In my last post I went over this, so to summarize, the paper they cited - the one single paper - used data from a questionnaire to determine,,,:

how many episodes of the following diseases/complaints the child had experienced in the last 12 months: common colds and other upper respiratory tract infections (hereafter called common cold), otitis media, pneumonia, gastroenteritis with vomit or diarrhea, and urinary tract infection.

Only the common cold and gastroenteritis gave any kind of statistically significance and that was only for the number of episodes, which I think I showed in my last post was insignificant even though it was statistically significant.

I contend that the evidence presented does not show an "increased frequency of common infections" which means we can cross that off the list as to why "concentrations of PFOS and PFOA in breast milk" could be a "major concern."

This leaves "undermine childhood immunization programs" as a possible "major concern" as all they presented as evidence were two citations.

1. Pre-natal exposure to perfluoroalkyl substances may be associated with altered vaccine antibody levels and immune-related health outcomes in early childhood
2. Serum Vaccine Antibody Concentrations in Children Exposed to Perfluorinated Compounds 

Let's have a look shall we...

Next post: Part 5