Monday, March 2, 2015

Is Tritan Plastic Free of Estrogenic Activity? (Part 1)

[Note: This is the first part of a 3-part series taking a critical look at the work of University of Texas - Austin neuroscience Professor George Bittner regarding estrogenic activity in plastics. Part 1 here gives general criticisms of his work in this area, while Part 2 and Part 3 which looks critically at the results of a pair of 2014 publications.]

It's been a while since I've discussed the work of neuroscientist Prof. George Bittner who claims to have found estrogenic activity (EA) in a wide range of plastic materials, not just polycarbonates that are known to show EA due to the residual bisphenol A (BPA) that resides within them, but polyethylene, polypropylene and more. Pretty much all plastics were implicated, which was quite shocking. This paper came out back in 2011 and he worked up quite a publicity train of hype trumpeting the results in interviews with major news outlets such as the New York Times. Not only was this PR tour driven by his "results", but also by the fact that he owns two companies, Certichem and Plastipure, which are involved in running these types of tests and then supplying plastics that pass the tests, respectively. So you could say there was a potential conflict of interest.

I (and other researchers) had no problem in quickly finding major flaws in the work. His work involved "stressing" the samples, and it was these stressed samples that showed high levels of EA. But there were significant problems with his stressing protocols, namely that he had no controls at all. While Bittner would argue that an unstressed sample would be a control, it isn't. Whenever any is running accelerated "stressing" of plastics (more commonly known as accelerated aging), you need to have control samples that are undergoing natural aging. Without those naturally aged controls, you have no idea if the stressing is in fact aging the samples properly or if it is producing unnatural results.

The classic example are chicken eggs. Heating up a dozen of them in boiling water for 10 minutes is not going to give you a batch of new chicks. That's because excessive heat accelerated undesired chemical reactions, reactions that don't occur in natural aging. Heating and cooling the eggs only within a very-narrow temperature-window will speed-up/slow-down the hatching. Anything else will produce unnatural results.

Or think of it this way, in terms of an imaginary movie script. The bad guys want to know where the good guy keeps some unknown valuable item that they are looking to steal. The natural-aging analogy would be for the bad guys to tail closely the good guy. The accelerated-aging analogy would be for the bad guys to be driving faster ahead of the good guy, occasionally looking in the rear view mirror to see that he's still there. If they correctly predict the good guy's route, they will get to the valuable item first. But if they look back and see that he's turned onto a different route, then the bad guys need to turn around, go back to that turning point and continue. It would be crazy for the bad guys to drive quickly without ever looking back at the naturally-aged control (i.e., the good guy). Such a scene would mean only that they will get somewhere fast, but it may or may not be the right spot at all. Yet that was what Bittner was doing. Going somewhere fast, but with no idea or proof that the final result was correct at all.

And this is not just me saying this. Take a look at these three pictures.
Outdoor Weathering Facility
Miami FL, USA









Phoenix AZ, USA
Magdeburg, Germany
These are all large outdoor weathering facilities and there are dozens of others from around the world that are not shown. If accelerated aging was merely a matter of counting photons, these facilities would not be needed at all.

For Bittner's research, it was even more important than usual to have a proper control as his test methods never identified what specific chemicals were showing the EA. And so it was impossible to know whether it was one or more chemicals that were created during the stress that didn't even exist in the unstressed plastic. Or if the the chemicals would ever develop under natural aging conditions.

Beyond lacking in a naturally aged control, Bittner's stressing protocols were extreme and therefore all the more likely to produce erroneous results. He simulated natural UV aging by exposing the plastic to 254 nm UV light, light that is not naturally occurring on earth, light that is known to be highly energetic and destructive to organic materials. Hence it's use as a germicidal lamp. Photons with a 254 nm wavelength chop up chemicals like a wood chipper chops wood, and all little bits are new chemicals that weren't there before. (Hence my very strong concern for a naturally-aged control.) Similarly, Bittner simulated a dishwasher with an autoclave. (Huh? Don't they have dishwashers in Austin, Texas?) An autoclave produces much higher heat than any dishwasher and it also doesn't "wash" anything. A dishwasher loaded with soap would wash away chemicals that diffuse to the surface which would decrease the chance of producing positive EA results. Similarly, Bittner ran a bunch of plastic samples repeatedly through a microwave. While this appears to be a realistic procedure, very few people run the same container 10 or more times through the microwave without washing it in between uses. And such a washing step would reduce any EA chemicals at the surface. You can now see that these "stress" tests were really just doing a bunch of extreme things to plastic samples that are not correlated to realistic conditions at all. I stated all of this in earlier posts back in 2001. (And it seemed to have had an effect as you will see in Part 2 of this series of posts.)

The accusations made some people upset, including Eastman Chemical. Eastman makes the Tritan family of plastics and has been pushing them heavily as a BPA-free alternative to polycarbonate. Bittner accused Tritan of showing EA, Eastman disagreed and the gloves came off, only being put back on after a jury in Texas agreed that Bittner's claims were invalid. Bittner appealed and lost there too.

Bittner has not given up the fight however. He published two new articles on the same subject matter late last year (which I will criticize wholeheartedly in parts 2 and 3), and is still making interviews, such as a recent one to National Public Radio.
"...Bittner's companies have changed their tactics a bit, says Mike Usey, the CEO of PlastiPure. 'We don't talk about Tritan, or Eastman, in a commercial context concerning the testing results that we have,' he says. 'But that doesn't limit our discussing our research in a scientific context.' That means Bittner and his companies are getting their message out by publishing scientific papers about estrogenic plastics that specifically mention Tritan and products made with it."
While they have changed their tactics on the PR trail a bit and are very careful in their new papers how they mention Tritan, they haven't changed their research tactics. They are still lacking in proper controls, and worse yet, they ignorantly continue to find new ways to abuse plastics without merit or reason, thinking that they are proceeding just fine. Bittner and company may well be fine neuroscientists, but they know next to nothing about polymer chemistry and processing plastics.

A leopard cannot change its spots.


Previous Years

March 2, 2012 - Cancelling a Stink with another Stink?

March 2, 2011 - Nonlinearity in Rheology - Be Afraid, Be Very Afraid

March 2, 2010 - Living without Plastics?

March 2, 2009 - Polymers and their Solubility

March 2, 2009 - Mylar - What it Isn't


Friday, February 27, 2015

Sometimes, Being "Cheap Plastic" is a Good Thing

As much as I generally despise the phrase "cheap plastic", there are times where being a low cost material can produce some unexpected advantages. Such as when people steal manhole covers in order to sell off the metal to a recycler. Plastic manhole covers bring less per kilogram for anyone recycling them, so the temptation will be less, even though it should be a lot easier for someone to steal them due to their low weight.

This is not the first time that plastics have been substituted to foil metal thieves. I wrote a couple of years ago about some local thieves who stole the copper piping used to cool a local outdoor skating rink. The Park Board replaced it with crosslinked polyethylene tubing.

Don't you dare think however, that plastic is so low in value to never be stolen. It is stolen frequently (1, 2 and 3). It's just that to make it worthwhile, you need to steal large quantities - truckloads and such.






Previous Years

February 27, 2013 - Elephants and Plastics - They Go Together


Tuesday, February 17, 2015

Trian vs. DuPont - Round 3

Nelson Peltz and his Trian Partners Group is still dogging DuPont. Having lost the last round (when DuPont explicitly told him that no, he cannot be on the board of directors and that DuPont was going instead add 2 more of directors of their own choosing), Peltz is still hoping a proxy fight will get him the directorship he so craves. And just like what Daniel Loeb did when he was attacking Dow, Peltz now has his own website, dupontcanbegreat.com [*]. His nominees for 3 other director chairs are rather scary, all being financial guys. (It takes more than fancy financial manipulations to effectively manage a company. See Google, Apple, Amazon, IBM and 3M for counterexamples. See Enron, Bears Stearn and Bernie Madoff for examples of how financial numbers that look great can end up being a complete fraud.) But even more so, I wonder about Peltz himself.

His only experience in running a chemical-type company was Avery from 1984 until 1992 and the results weren't too impressive. In early January of 1984, Avery stock was around $6.50 while at the end of 1992, it was around $13.88. While a 214% gain seems impressive, the S & P 500 rose 260% during that same time frame. Meaning he couldn't even keep pace with the general market. I think Peltz would call that underperformance, but he still thinks he has great advice on how to run DuPont.

Again, I don't follow DuPont's business performance too closely and maybe they do deserve to improve, but I really am bothered by this activist investor approach. If you own stock in a company that is stinking up the joint, then you may try and hype it up some in order to get the price to rise. But the activist investors aren't hyping up DuPont. They are trashing it in about every way possible. All of which raises this question:
"If the company is really that badly off, then why would anyone ever buy up such a large share of it?"



[*] Dupontcanbegreat.com? Couldn't someone have spent more than a few seconds coming up with that grade-school level name? And these guys think they have great advice on how to run the company?


Previous Years

February 17, 2012 - Reusing Old CD's - but for Artists Only

February 17, 2011 - A Single Phase Gel from Buckyballs?

February 17, 2010 - Potpurri

February 17, 2010 - Twitter

Wednesday, February 11, 2015

The Plastic Number

Yesterday I stumbled upon something new - The Plastic Number. This does not refer to the recycling numbers (1-7) on plastics items, but instead is a mathematical constant. Given the symbol P, it is an irrational number, P = 1.324717957244746025960908854... It's closely related to its more famous cousin, the Golden Ratio, f = 1.6180339887498948482...For instance, the Golden Ratio squared is equal to the Golden Ratio itself plus 1. For the Plastic Number, the Plastic Number cubed is equal to the Plastic Number itself plus 1.

The Golden Ratio is increasingly approximated by the ratio of adjacent terms in the Fibonacci sequence, while the Plastic Number is increasingly approximated by the ratio of adjacent terms in the Padovan Sequence. The Golden Ratio is used in making the Golden Spiral:
Golden Spiral
The Plastic Number on the other hand, was recently discovered to be useful in making a new type of spiral - the Harriss Spiral:
Harris Spiral

The Plastic Number was first extensively studied by G�rard Cordonnier in 1924 G�rard Cordonnier in 1924 and then later by the Dutch architect Van der Laan. But all this raises the question of how/why was this number given the Plastic name? Back in 1924, the word was still being used in its traditional sense of "moldability", but I don't see how that can possibly be applied here. The number P is fixed. I'm going to have to do some asking and digging on this as I'm very curious.

Golden Spirals are common in nature, such as in nautilus shells, but I don't recall ever seeing any naturally occurring Harriss spirals. But now that people know the spirals exist, perhaps someone might find one. It would be ironic if it occurred in a synthetic polymer, wouldn't it?


Previous Years

February 11, 2014 - What Else Do We Need To Ban Besides Azodicarbonamide (Subway, Are You Listening?)

February 11, 2011 - Top Killing with Oobleck

Tuesday, February 10, 2015

The Most Egotistical of All the Activist Investors

While I would broadly claim that activist investors, with their penchant for running media campaigns putting themselves at the center of attention (and not the supposed problems with their targeted company), are egotistical, Nelson Peltz of Trian Management has raised the bar to a new level. You may recall from a month ago that Peltz took a small position in DuPont and started demanding changes, including having 4 of his directors put on DuPont's Board of Directors. One of the initial recommendations was Peltz himself. Fine, whatever. But that actually now appears to have been not only a request, but his highest demand. DuPont met with Peltz and agreed to let him have a director on the board, as long as it wasn't Peltz. No deal! Peltz insisted that he be the director or he was going to go home and hold his breath. Such an ego! What is so special in the little brain of this guy that he and he alone has to communicate it?

DuPont was quite fine to let him storm off as they immediately afterwards added 2 directors of their own choosing. Geesh Nelson, you could have had 1, but now you have nothing, and the board is that much bigger and more loaded with people favorable to the current management, so that you can even could consider that as a -2, meaning that the score for you suddenly swung by -3 in your direction. And you think you know how to run a company?

Esteemed fellow blogger Chemjobber pointed out to me a couple 1 and 2 articles in the Economist that give an alternate perspective of activist investors. They are well written and do provide an alternative perspective, but I'm having none of it because the articles tacitly assume that all this activism is unquestionably good and that these are good individuals that know what they are doing. Huh? So if you are an activist investor you are automatically qualified as competent? No other field on earth makes that claim. There are bad doctors, lawyers, cops, engineers, chemists, CEOs, teachers, professors, janitors, receptionists, salespeople, actors, singers, athletes and so forth, but bad activist investors? No, they are all quite skilled at their jobs.


Previous Years
February 10, 2012 - Birds and Gels and Arsenic

February 10, 2012 - A Sign Your Oven Might Not Be Working Properly

February 10, 2010 - Valentine's Day is Coming...

Monday, February 9, 2015

The High Cost to Make Cheap Plastic

Courtesy of 123Designs, we have this infographic about the costs of making stuff out of cheap plastics.
Infographic on tooling costs
The idea that the graphic is trying to get across is that making stuff out of cheap plastic ain't cheap but the numbers on the vertical axis (either vertical axis) are way off.

This graphic is only about the tooling cost - it assumes that you already have the necessary process equipment installed and operational. So if you already own the $10,000 3-D printer, you really don't need to spend anything on tooling to print your prototype cell phone cases. But if you already own the $300,000 injection molding machine, you need to buy the mold before you can start cranking out thousands of parts per hour. But molds are going to be way more than $30,000 for steel, (try a factor of at least 3). And that assumes you get the mold designed correctly the first time. You may have to go back and remachine it, taking out a little bit more metal here and there to get the flow to fill the mold properly so that you don't end up with
  • excessive shrinkage
  • excessive warpage
  • sink marks
  • flow lines
or any of a myriad of other problems.

But the graphic does get the big picture across - options exist to make "cheap plastic" products on a variety of scales. But to cheaply make something from cheap plastics requires some deep pockets. As the old joke goes, "How do you make a small fortune in the plastics industry? Start with a large fortune!"



Previous Years

February 9, 2011 - Peanut Butter Rheology

February 9, 2011 - Gluing Feathers on a Bird

February 9, 2010 - I gotta look closer

February 9, 2007 - This is why Chemists fear HF acid

Thursday, February 5, 2015

Consuming Plastic

Plastics touch nearly all aspects of our lives, but there is one area that they are noticeably absent from - food. Very little in the way of synthetic polymers are taken in through the mouth. But that will be change for me in a few hours. Later this afternoon I get to consume about 250 g of polyethylene glycol (PEG) with a molecular weight of 3350 Da. Mix into 2 liters of Gatorade, it will taste pretty good, but I really don't recommend this diet for anyone except when advised so by a doctor. (I have been so advised.)

When we first start visiting the doctor for annual physicals, we are told to stick out our tongue and say "Aaaaah". But after 50 years or so, the doctor gets bored with that and decides to start looking at the other end of your GI tract. He/she gets a better view when the road has been cleared, hence the PEG diet. PEG 3350 is an "osmonic laxative".

The rheology of feces can be quantified by the Bristol Stool Scale which runs from 1 to 7:
250 g of PEG 3350 is normally consumed over 14 days, so consuming it in 2 hours is going to, in the words of Spinal Tap, turn it up to 11. And I'll be feeling plenty....wait for it....wait...wait....crappy! (Feel free to add your own puns in the comments below.)




Previous Years

February 5, 2010 - "BPA Free"?

February 5, 2010 - A new concept in hearing aids

February 5, 2009 - Coloured Plastics