Breast Milk and PFASs - Part 3

The Mogenson paper "Breastfeeding as an Exposure Pathway for Perfluorinated Alkylates" that initiated the "Breast milk may be tainted with toxic chemicals" news articles on Google make this statement as to why PFASs are a possible concern if they are found in breast milk:

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.

Let's look at their statement that PFASs result in an "increased frequency of common infections."

This is based on a single paper they cited titled:

Pre-natal exposure to perfluoroalkyl substances may be associated with altered vaccine antibody levels and immune-related health outcomes in early childhood.

 Here is what the author's of that cited paper conclude:

In the present study, PFAS concentrations were associated with reduced antibody levels to the rubella vaccine and increased number of episodes of common cold and gastroenteritis, suggesting that pre-natal exposure to various PFAS may lead to immunosuppression in early childhood.

Now I am not at all good with them there statistics these science papers use. I am, however, good enough to look stuff up and get a feel for what is going on with the data they report.  They say there are lies, damn lies, and statistics, and I agree.  I have read enough journal peer-reviewed papers to come away scratching my head as to how they can conclude what they do and put it in a paper for all the world to read.

The reason I am once again going on and on about a single topic is to provide support for why I think it has committed a wrong.  In this case, it is not that the data is wrong - it may or may not be - it is the simple fact that what they elude to - that "breastfeeding being an important exposure pathway to some PFASs in infants" sends the wrong message to the public and specifically mothers who want to do what is best for their baby.

Assuming that breast milk does increase the amount of PFASs in the baby, does that increase contribute to a negative health outcome?  The two papers they cite state that these compounds "may undermine childhood immunization programs" as well as "increased frequency of common infections."

Let's look at the evidence to support the "increased frequency of common infections."

According to the cited paper "Pre-natal exposure to perfluoroalkyl substances may be associated with..." the mothers in the study were asked in a questionnaire:

Concerning infectious diseases, the mothers were asked 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.

The authors report:

When analyzing common cold for the third year of life as a binary variable (yes/no), no statistically significant associations were found (Table 5).

This means that there was no difference between the exposed group and the non-exposed group (the control) when asked the yes/no question on colds.

They then state:

With regard to infectious diseases, the maternal concentrations of PFOA and PFNA were positively-associated with the number of episodes of common cold for both the children’s third year of life and all 3 years merged. PFHxS was positively-associated with the children’s number of episodes of common cold for all 3 years merged in the bivariate analysis only (Table 5).

No statistically significant associations between perfluoroalkyl substances and the common cold,  otitis media, pneumonia, gastroenteritis with vomit or diarrhea, and urinary tract infection.

They state that they found that "increased concentrations of PFOA and PFNA were associated with increased number of episodes of common cold."

The statistical data they present in Table 5 resulted from:

Poisson regression analyses were used for health outcomes consisting of count data (number of episodes of common cold and and gastroenteritis),

Like I said earlier, I am not well versed in all things statistics.  So I went looking to see what the "β-value" in Table 5 means:

I went a Googeln' and found this helpful information:

Assuming I am understanding this correctly a higher  β-value supports the claim that "increased concentrations of PFOA and PFNA were associated with increased number of episodes of common cold."

With regard to infectious diseases, the maternal concentrations of PFOA and PFNA were positively-associated with the number of episodes of common cold for both the children’s third year of life and all 3 years merged. PFHxS was positively-associated with the children’s number of episodes of common cold for all 3 years merged in the bivariate analysis only (Table 5).

The question I have, when looking at Table 5's data for he common cold, is what does positively-associated actually represent here?

What the authors of this paper report is an increase that is statistically significant when the β-value had a p-value ≤ 0.05.

The data that gave them this statistically significance β-value in Table 5 that supports their claim of "positively-associated with the children’s number of episodes of common cold" comes from a questionnaire given to the mother.

At the age of 1, 2, and 3 years, a questionnaire was sent to the participants. ...Concerning infectious diseases, the mothers were asked how many episodes of the [common cold] the child had experienced in the last 12 months.

Yeah, these mom's may recall with 100% accuracy the number of colds their child got last year, and when you put all the numbers into the statistics computer program it spits out a β-value and a p-value, but does a p-value below 0.05 support anything other than the β-value being statistically significant?

Yippie!  I saved one dollar on my purchase of a new car!  That's a positive increase in my bank account!

If you look at the β-values associated with those p-values, they are not big numbers.  If you look at all the data on incidence of common colds reported by the moms, 50% showed no statistical significance.

The authors are not incorrect when they state "positively-associated with the children’s number of episodes of common cold" its just that the "positive" they are speaking about looks to be an insignificant increase.

When you add this to the fact that a questionnaire that asks a mom to recall the number of colds in the past year is fraught with bias and error, and you look at the very small number of participants, the support for the statement in the Mogensen paper on Breastfeeding that "adverse effects of PFASs reported in children with similar serum-PFAS concentrations include...increased frequency of common infections" should never have been made.

Do I need to show you the results for gastroenteritis or will you take my word for it that it paints the same picture as the common cold data in Table 5 did?

Statistically significant results should actually mean something other than they were statistically significant.

Next post: Part 4

Breast Milk and PFASs - Part 2

Let's look at their paper (sorry, its behind a paywall so I cannot link to it.):

Breastfeeding as an Exposure Pathway for Perfluorinated Alkylates

Why the big deal?  Why do the five authors believe that PFASs in breast milk is a potential concern?

If it is in breast milk, then there is uptake by the baby.  Now the baby has PFASs in their system.  What's so bad about that?

PFASs can have immunotoxic effects, and a major concern is that PFAS exposure may undermine childhood immunization programs.

and...

Due to the particular vulnerability of the immune system during early development, the sources of PFAS exposure in infants are of special interest.

That's why these guys think their study is important.  Because "PFAS exposure may undermine childhood immunization programs."

What is that based on?  They cite a paper called "Serum Vaccine Antibody Concentrations
in Children Exposed to Perfluorinated Compounds" (which is behind a paywall so I cannot link it).

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.

There were adverse effects on humoral immune function observed.

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. 

Exposure increased the odds of antibodies being below the protective level.

If the associations are causal, the clinical importance of our findings is therefore that PFC exposure may increase a child's risk for not being protected against diphtheria and tetanus, despite a full schedule of vaccinations. 

What they found was this:

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

I am not going to argue CIs or PFOSs or PFASs or whatever.  I am going to take their data as is.  A 2-fold increase in concentration decreased the antibody concentration for tetanus and diphtheria, (keep reading to see how this 2-fold issue came about)

This is where I separate from the five authors.  If they are basing their concern on this:

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.

...then the benefits they attribute to WHO:

Breastfeeding is recommended by WHO as the exclusive food source for infants during the first 6 months after birth and onward partially with supplementary food up to age 2 years.

...must be less then the risk of a "decreased antibody concentrations toward childhood vaccines and increased frequency of common infections" for a mother to stop breastfeeding.

PFASs are a concern because of a "decreased antibody concentrations toward childhood vaccines and increased frequency of common infections" according to the papers authors.

Their paper generated this news article stating:

BREAST MILK IS BEST FOR BABIES BUT THE MOMS COULD ALSO BE PASSING HARMFUL CHEMICALS

See what you started?  Hopefully you can see where I am going with this and why it bothers me.  If one mother changes her mind about breastfeeding because she does not want to pass harmful chemicals to her baby, then the positive benefits of breastfeeding, as described by WHO, will not be received by that baby.  One risk is substituted for another risk. 

This means that there had better be a real risk of "decreased antibody concentrations toward childhood vaccines and increased frequency of common infections" when breast milk is given to the baby., and that risk is substantially decreased if the baby receives formula.

Then, if formula is used, the benefits not received from breastfeeding are negated by that decrease in risk of decreased antibody and frequency of common infections,

This makes me ask the question; how confident am I in the data they used to make the statement "decreased antibody concentrations toward childhood vaccines and increased frequency of common infections."

I am pretty confident in the data that WHO used to recommend breastfeeding.  There is a lot of it out there.  But for PFASs and PFOS there is not.  There seems to be a small group looking at into them and they seem to cite each other's papers.  That makes me a little skeptical in how "bad" they might be.

Now I am writing this, like I usually do, in real time.  That is, I do not have the data in front of me.  I write as I look it up.  I have no pre-formed conclusion on the validity of their findings and data.  I am concerned/agitated because I think they found all the attention on their work outweighed their concern that women may look at it and chose not to breastfeed, because, you know, these smart scientists, one from Harvard no less, found that breast milk could be exposing a baby to toxic chemicals.

There had better be some convincing data to justify the decision a women might make to not breastfeed based on this journal article and the news stories about it.

Next Post: Part 3

Breast Milk and PFASs - Part 1

This caught me a bit off guard on my Google News Feed:

Huh? soon gave way to no, no, no...please don't go there.  And that was without looking at the data to support that headline.

Having gone through a public health masters' program, you get indoctrinated into the concept of the of "the greater good."  You learn that there is a risk of a negative health outcome with almost everything you do, drink, eat, breath, or come in contact with.  You decide based on what gives you the best outcome overall.  And you decide based on compelling evidence to do, or to do not.

I am a chemical hazard guy.  A hazardous waste guy to be specific.  I like looking at chemicals and their risk.  I buy into the notion that there are positive health outcomes when you decrease the amount (dose) of the chemical.  I also accept that there is a dose you - including a baby - can be exposed to where there is minimal risk of a negative outcome.

I also accept, advocate, and believe to be true the "Donnelly Risk Paradigm" which you can read about here.  Basically, if there is exposure, there needs to be uptake and there needs to be a negative health impact.  Without exposure there is no uptake, without uptake there is no negative health impact.  The problem here is, that even if there is exposure and uptake there does not necessarily manifest a negative health outcome since the body is pretty good at detoxifying stuff that gets into it.

Limiting exposure is a good thing but exposure and uptake does not mean a bad thing will happen (see the liver).

With this in mind, let's look at the paper that got Google to tell the world about breast feeding giving your baby toxic chemicals.

Philippe Grandjean, the study author and environmental health expert at Harvard T.H. Chan School of Public Health stated that it was indeed an absurd situation breastfeeding women need to think of the kind of chemical exposures they could contribute to the child although breast milk is heralded as the best possible source of nutrition for the baby.

Wait...Harvard...no, no, no...Will this journal paper discourage a new mom from breastfeeding her baby?  Was that considered before they published it?  One news article goes on to quote one of the authors on this:

Grandjean and the other experts continue to emphasize that breast milk still is the best food for babies. But, it is just that it is less healthy and pure than was intended by nature and previously believed.

That's real helpful there professor.  What the public now sees is "Breastfeeding can expose babies to toxic chemicals."

Arggg.

Remember, the greater good!  Breastfeeding is for the greater good of the baby.  If you are going to tell new mothers that their breast milk is "less healthy and pure" then you should have anticipated it going full speed ahead to "breast milk may be tainted with toxic chemicals" once the press got a hold of it.  You and your cohorts on this paper should have understood this, so your research better show that breast milk is contaminated high enough so that continued feeding is more harmful to the baby then the benefits.

Before I go on, please note that I am all for this type of research.  It is important to understand exposure pathways.  If PFASs are causing harm, then this type of research is important.  But you need to chose your words carefully and keep this research on the down-low, because all the public sees is "Breastfeeding can expose babies to toxic chemicals."

And armed with that Google news feed title, can you blame a new mother for choosing not to breastfeed?

Next post: Part 2

Oops! EPA Accidentally Pollutes the Animas River

Edit: March 18, 2016: BOI Report on the incident. 

Rivers are not supposed to look like this.

Source

Update video on the spill.

For those readers who may be looking at the news, and the recently posted lab data, maybe I can help make some sense out of those numbers.

I am a public health guy.  I love fish and plants as much as anyone else, but I really don't deal with aquatic toxicity.  So looking at the lab results, I see a lot of "metals" that are not the toxic metals to human health I deal with,

By the way...Ignore all the letters by the results.  Those are important, but, for all intents and purposes, the values reported are the values we can assume were actually present at the time the sample was taken.  D, for example means they had to dilute the sample to get it low enough for the instrument to read it without overloading it.  Too much and the instrument's reading goes off the scale, so you dilute it, and then take the result and estimate how much is in there.  There is error put into that result when it is denoted with a "D", but again, these results are so high that potential error is meaningless.

Let's look at sodium for example.  The lab reports a maximum concentration of 11,100 ug/L at the the 32nd St Bridge.

That's 1,110 parts per million, ug/L is ppb, there are 1000 ppb in one ppm.

So I asked myself, 'what is the normal sodium concentration found in freshwater streams?'

Good ol' Google...Sodium looks to be about 5 ppm as a high concentration.  So the sodium is elevated for sure, but less than sea water (10,500 ppm).

Now let's look at the human health concerns.  Assuming there is no cyanide, the primary concern for this water coming from a mine is the heavy metals, and for those, I want to look at just what we call the "RCRA 8."

Looking at the analytical results, it looks like only lead is a really big concern - human health wise.

Source

Let's look at two of the metals.  The others are important, but these two have the highest concentrations and are a bigger deal toxicity wise.

Arsenic looks to be about 1080 at the highest concentration found.  As you can see above, the MCL - U.S. EPA's drinking water standard - is 10 ug/L.  Now remember, that's for drinking the water.  And not just drinking it once, but drinking two liters per day, almost every day, for 70 years.  Drinking a glass of this water would not, based on the lab results shown, be a concern (it would probably taste terrible though).  Potable and Palatable!

Lead...on the other hand...well...

25,600 ug/L at sample location "A72."

The MCL for lead is 15 ug/L

That's 25 ppm of lead in that sample.  See the TCLP results above for lead?  5 mg/L or 5 ppm..

That water, from location A72,  meets the definition of a hazardous waste,  Not that that makes it "toxic", it just shows that the concentration of lead is pretty gosh darn high.

So...dilution will be the solution to pollution here, but this river was heavily contaminated by some toxic stuff, that should have never gotten into this river (call me Captain Obvious).

It will be interesting to see what takes place to the environment as this water makes its way downstream.

Time will tell.