Category: Chemistry

The Great Healthy Yard Project: a talk at the Wilton Library

Last night we heard a talk by Diane Lewis, MD on The Great Healthy Yard Project (their web site is tghyp.com, run by Lewis from her home in Bedford, NY. Trained as a nephrologist (kidneys) and an internist, Lewis is not currently practicing medicine but devoting her time to promoting her project: reducing groundwater pollution by reducing the use of lawn chemicals. The talk was co-sponsored by Wilton Go Green, the Wilton Conservation Commission and the Wilton Garden Club, who introduced the speaker. The talk was recorded and will soon be on the Wilton Library’s website.

Lewis has also written a book on this issue with the same title, which is available on Amazon. She also has published articles summarizing her views in the New York Times and in the Baltimore Sun. A short 3-minute video on the tghyp website summarizes her position.

Lewis’ thesis is that “chemicals” from our lawns and gardens run off into the groundwater and eventually are found in our drinking water. As to which chemicals are of greatest concern, Lewis was quite vague as she mentioned none specifically. Were insecticides of more concern than fertilizers? Probably, but she didn’t actually say so.

She noted that the EPA is quite concerned about this runoff claiming that there is runoff in 70% of streams. The EPA does have a page with good and specific recommendations here. You can also find good descriptions of the problem at the US Geological Survey web site.

Lewis feels that this runoff into our drinking water is a serious problem and that it may be cumulative and could “damage our DNA,” although she presented no evidence for this somewhat surprising conclusion.

Endocrine disruptors

Central to her argument is that these (unspecified) chemicals are endocrine disruptors which even at very low levels may cause harm to humans. The whole idea of endocrine disruptors is controversial, however, and has not been definitively established.

The Endocrine Society has published two reports in this area. The 2009 report described the problem but noted that “Unfortunately, it is virtually impossible to make direct links between such epidemiological observations and exposure to given chemicals.” And, a key scientific paper in Science was withdrawn because of apparent scientific misconduct.

Needless to say, there are naysayers in this area, and one published by EndocrineScience.org criticizes the Endocrine Society, but this report was published by a manufacturer’s group, the American Chemistry Council.

Lewis suggested that these endocrine disruptors could be the cause of increased breast cancer, prostate cancer, diabetes, ADHD and autism, but really offered no science to support these views. When I talked with her afterwards, she said there were papers on rats showing that they take on autistic symptoms after treatment with some “chemicals,” but did not cite one specifically. She suggested that these chemicals could be one of many contributing causes, and this is borne out in papers (also here and here). But one problem with this hypothesis is that recent work shows that there has been no increase in autism occurrence in the past 30 years.

Confusion and misinformation

In her gardening segment, Lewis lost ground with reality by suggesting somehow that “eating organic food” would be beneficial, even though there is no evidence that organic food is more nutritious, tasty or safer in any way. In fact, the classic paper by Bruce Ames showed that the toxic and carcinogenic pesticides generated by plants themselves were present at a level 10,000 times higher than any pesticide residues.

She also suggested that the decline in Monarch butterflies was caused by the planting of “GMO” crops, but backed off when I pointed out that large agriculture plowing fields to remove milkweed as well as eliminating by herbicide is the actual cause. This whole issue is explained here by Amber Sherwood-K and Jon Entine. The slide that suggested that a solution would be “Don’t eat GMOs,” was thus complete nonsense.

She also went astray in suggesting that the WHO had declared that glyphosate (Roundup) was carcinogenic. In fact this was done by the IARC, a subcommittee of the WHO and in doing so they ignored substantial evidence to the contrary, as described in this report in Scientific American. And they have also found caffeine, alcohol, sunlight, and the hairdressing profession in that same category.

Meanwhile the German Federal Institute for Risk Assessment completed a 4-year assessment for the EU, considering 150 new toxicological studies, all available existing toxicological studies (more than 300) and nearly 900 peer-reviewed publications, concluding that

the available data do not show carcinogenic or mutagenic properties of glyphosate nor that glyphosate is toxic to fertility, reproduction or embryonal/fetal development in laboratory animals.

Gardening advice

In the last part of her talk she suggested growing more local plants that would require less care and fertilizers that could run off. Some of particular interest were cardinal flowers, Joe Pye weed and Monarda (bee balm).

We found it surprising that in this talk she avoided mentioning any “chemicals” by name, and she told us this was because this was a layman’s talk. Without naming them, she mentioned that some were listed in her NY Times article. These were glyphosate, carbaryl, malathion and 2,4-D. Of these, glyphosate and 2,4-D are herbicides of very low and relatively low toxicity. Carbaryl (also called Sevin) and malathion are moderately toxic to humans (and carbaryl to bees), but are generally used only in small amounts in gardens and probably are not major runoff candidates. Glyphosate binds to the soil and is seldom found in runoff.

During her talk Lewis had a great deal of trouble pronouncing bacillus thuringiensis, which might indicate that she is uncomfortable pronouncing these chemical names and thus leaves them out of her talks.

Overall, as a chemist, I was not happy with her demonizing the entire class of “chemicals” as all bad without any specific science to back up her assertions. However, her heart is generally in the right place in wanting to reduce runoff from suburban lawns into our water supply. We haven’t treated our lawn with anything in years, so we are way ahead of her, perhaps primarily because we are lazy or cheap, but our lawn still looks fine when it rains enough.

McCormick plans to scam consumers with ‘organic’ spices

McCormick has announced plans to “significantly increase the number of organic and non-GMO offerings in 2016.” And, based on the spices already on the shelves, this will be at a significant price increase. We looked at a few McCormick spices and found that organic oregano was $5.19 and regular was $3.29. And organic basil was $5.99, while conventional was $3.39 for an even bigger bottle.

And what are consumers getting for all this money? Scammed! Both organic and conventional crops are sprayed regularly: just with different sprays, and the organic plants are usually sprayed more often, because the organic-approved insecticides are much less effective.

And, as Bruce Ames pointed out in a classic PNAS paper, most plants make their own carcinogenic insecticides, and they are present at a level 10,000 times that of any applied insecticide. Further, since spices come from all over the world. Huy Fong Sriracha Seasoning Sticks is barely credible that the baroque organic rules can be enforced uniformly.

Finally, McCormick also is making a big deal of their spices being “non-GMO,” even though there is not a shred of evidence that GM crops pose any sort of harm despite being in use for nearly 20 years. But what does this mean? There are no GMO version of any spice plant!

It seems that this all comes down to vanilla. Not vanilla extracted from vanilla beans, but vanillin, the synthetic version of the principal component of vanilla flavoring. Vanillin can be synthesized in a number of ways, and one us through the use of synthetic biology, in which yeast are bred or designed to create vanillin by fermentation. The process was developed by the Swiss company Evolva, in partnership with International Flavors and Fragrances (IFF).

Now, if the bacteria Evolva/IFF use are genetically modified, some paranoid consumers might think that the pure vanillin the bugs produced is somehow “genetically modified.” This is chemical nonsense, of course, vanillin is a simple 8-carbon compound and easily purified such that its precursors do not matter. While the GMO Compass organization believes that vanillin so produced would not have to be labeled because it is the same, pure compound, Food Navigator reports that it would not qualify for the “non-gmo” stamp. This seems to be more of a theological than a scientific dispute.

The Motley Fool has a good summary of the business considerations in making vanillin using biotechnology.

Meanwhile, McCormick, ever ready to trash science in the name of gouging consumers decided to use vanillin in the artificial vanilla products that was not produced using biotechnology.

Just yesterday we learned of a hedge fund weasel, Martin Shkreli who bought up rights to the 62-year old drug Daraprim, and raised its price from $13.50 a pill to $750 a pill for no good reason except to line his pockets. This, frankly, is little different than what McCormick is doing, trading on consumer ignorance and the fictional organic halo created by lobbyists, recognizing that fear sells.

HFCS versus sugar

Sugar crystallizing on left, sugar plus lemon juice on right.

Ever since Michael Pollan mentioned HFCS (High Fructose Corn Syrup)in The Omnivore’s Dilemma, everyone is sure that HFCS is quite evil. To try to understand it, let’s do a little kitchen experiment. You can do this one at home and it’s kind of fun.

We’ll start as if we were going make rock candy, by putting one cup of sugar in a saucepan with ½ cup of water and bringing it to a boil. Let it boil gently until all the sugar has dissolved.

Then pour half of the mixture into a small bowl like a custard dish. You could also use a small juice glass as along as it is heat resistant.

Now, add about 1 tsp of lemon juice to the remaining sugar solution and stir it in while you bring it back to a boil. Let it simmer for 30-60 seconds and remove it from heat. Pour this remaining sugar solution into a second small bowl. Let the two bowls set undisturbed for 24-48 hours.

When you look at the two bowls after this time, you will probably see large sugar crystals forming in the first bowl. The other will probably remain pure syrup with few if any crystals. This is exactly the experiment we did in the picture shown at the top of the column, and you will see large crystals in the left flask and no crystals in the right flask. The only difference is that we use these tall slope sided (Erlenmeyer) flasks so you could see the crystals better. Since there is very little evaporation from these flasks it took a couple more days for the crystals to form.

sucrose color — Sucrose structure. Glucose on left, fructose on right.

OK, now what is going on here?

Table sugar, also known as sucrose is actually made up of two smaller sugars: glucose and fructose. They both have the same formula, C₆H₁₂O₆, but slightly different structures. (One has a 6-membered ring and the other a 5-membered ring.) After adding the weak acid in lemon juice, the two sugars come apart into the simpler sugars and the solution is no longer a single compound, but two quite different compounds which compete with each other and cannot crystallize because they are both there in equal quantities. The result is that the second dish stays a syrup and never crystallizes.

Sucrose split into glucose (left) and fructose (right).

And what is that syrup? It’s 50% glucose and 50% fructose. This syrup is called invert sugar and is sometimes used in baking. It’s also pretty much the same thing as honey, which starts out as a sugar syrup, but the bees secrete the enzyme invertase which unzips it into glucose and fructose just as we did.

But wait a second! HFCS or High Fructose Corn Syrup is 55% fructose and 45% glucose, almost the same thing as this syrup. In fact, if you wanted to make it exactly the same as HFCS we calculate that you could do this by adding a teaspoon of Agave syrup, which is often about 90% fructose.

So, we just made a syrup which is identical to HFCS, except we made it from sugar instead of corn. Clearly this syrup is just about exactly the same as the sugar we started with, and perfectly safe to eat or cook with, (except that that trace of lemon juice might be just slightly perceptible.) So there is no major difference in sweetness nor in nutrition or caloric value. It’s still a flask of sugar syrup.

Corn Syrup

But hang it all, we didn’t make it from corn! How can it be the same as corn syrup. But it is. By the time we’ve gotten it to this form, it is just a couple of simple sugars and it really doesn’t matter where we got them from.

Corn syrup is made industrially from cornstarch, because this scales better for large batches. They start with cornstarch, which is actually just a long chain polymer of glucose units and unzip them using a simple enzyme, alpha-amylase. When you get done with this treatment you can get pretty much pure corn syrup out of the reaction, a solution of pure glucose, also sometimes called corn sugar.

The problem with glucose is that is isn’t quite as sweet as sugar is, and if you want to use it in cooking or baking you need to make it sweeter. Well it turns out that fructose, or fruit sugar, is sweeter than glucose, and a mixture of the two can mimic the sweetness of table sugar or sucrose.

If we had to go and isolate fructose from fruit juice, this would be an expensive process. But, it turns out that you can convert glucose (6-membered ring) in fructose (5-membered ring) by mixing it with the enzyme glucose isomerase. Then we can mix the glucose and fructose 45-55 to make HFCS. Why not 50-50? Well, once you unzip sugar into glucose and fructose, it isn’t quite as sweet and you need a bit more fructose to get the same sweetness as sugar.

So what’s our conclusion? If we can essentially make HFCS from table sugar it can hardly be dangerous. It’s the same thing as sugar and perfectly safe. And, incidentally, it doesn’t matter whether that sugar came from cane or beets: it is still a single pure compound. Sugar can easily be purified to a very high degree of purity since it crystallizes so easily and any traces of impurities from farming are removed during that purification. The same holds for cornstarch.

Oh, and if you are wondering where those two enzymes come from, you can get the common bacterium bacillus amyloliquefaciens to make alpha-amylase, and the streptomyces flavogriseus bacterium to make glucose isomerase for you.