by Tom Lee
Earlier today my fellow IFAer Ben Adler Twittered a link to this Post column by Douglas Gansler, Maryland’s Attorney General. “A reason not to eat chicken, besides its blandness,” went the tweet, and indeed the linked article makes an emphatic case for avoiding factory-produced chicken. Apparently American poultry farmers have been giving their chickens an arsenic-containing compound in order to make the meat pinker. Arsenic! In chickens! The evil agro-industrial complex strikes again.
Except… well, there’s a problem. The arguments Gansler makes are sort of — how to put this delicately — weasely. And this will be apparent to anyone who reads them with a critical eye. Consider:
Why do our chicken, our water and our air contain arsenic? Because in the United States, most major poultry producers add an arsenic compound known as Roxarsone to their chicken feed. Inorganic arsenic is a Class A carcinogen that has been linked to heart disease, diabetes and declines in brain function. Recent scientific findings show that most Americans are routinely exposed to between three and 11 times the Environmental Protection Agency’s recommended safety limit.
Let’s leave aside the highly dubious claim that chicken feed is responsible for airborne arsenic pollution — that seems likely to be a mistake. The core claim that inorganic arsenic is bad for humans is true. So, uh, is that what Roxarsone is made of? Why no, it isn’t:
4-Hydroxy-3-nitrobenzenearsonic acid is an organic compound that is widely used as a food additive for chickens. The molecule is a derivative of phenylarsonic acid (C6H5As(O)(OH)2). This organoarsenic compound, usually under the tradename Roxarsone, has attracted attention as a source of arsenic contamination of the food chain.
Are organic arsenic compounds safe? Well, it depends. But at least some are:
Inorganic arsenic and its compounds, upon entering the food chain, are progressively metabolised to less toxic forms of arsenic through a process of methylation. For example, the mold Scopulariopsis brevicaulis produce significant amounts of trimethylarsine if inorganic arsenic is present. The organic compound arsenobetaine is found in some marine foods such as fish and algae, and also in mushrooms in larger concentrations. The average person’s intake is about 10–50 µg/day. Values about 1000 µg are not unusual following consumption of fish or mushrooms. But there is little danger in eating fish because this arsenic compound is nearly non-toxic.
We’re left wondering whether Gansler’s reference to an EPA limit concerns inorganic arsenic or Roxarsone. I think I know which it is. I also don’t think that the sloppy prose enabling this confusion is a mistake.
The poultry industry has been using the feed additive Roxarsone — purportedly to fight parasites and increase growth in chickens — since the Food and Drug Administration approved it in 1944. Turns out that the arsenic additive promotes the growth of blood vessels in chicken, which makes the meat appear pinker and more attractive in its plastic wrap at the grocery store, but does little else. The arsenic additive does the same in human cells, fueling a growth process known as angiogenesis, a critical first step in many human diseases such as cancer.
Ah, the dread angiogenesis. It’s true, angiogenesis is a characteristic of tumor cells — trying to inhibit the process in order to starve tumors of blood is the biological rationale behind a whole class of anticancer drugs. But of course angiogenesis is also necessary for the growth of animal tissue in general. Angiogenesis is something that malignant cancer cells coordinate in order to sustain themselves — they release growth factors that promote this process, which is normally largely dormant in adult animals. It’s a process that accompanies cancer, but not a cause of cancer itself.
Back to the inorganic/organic confusion:
In 1999, recognizing that any level of inorganic arsenic in human food and water is unacceptable, the European Union outlawed its use in chicken feed. Reportedly, several American chicken producers, including Tyson Foods and Perdue Farms, have acted responsibly by discontinuing the use of Roxarsone in their animals.
The first and second sentence are about entirely different classes of chemicals.
Finally, we come to some stats about chicken consumption and a plea for a ban on Roxarsone. Whatever.
So, look: I have no idea if Roxarsone poses a health risk. None of the above is dispositive; all things considered, I’d rather not have pinkening agents fed to chickens whose eggs or meat I plan to consume — it seems risky and unnecessary. But Gansler’s rhetorical sleight of hand makes me extremely suspicious, and the editing applied by the Post is credulous at best.
The word “arsenic” is a shorthand for a class of deadly compounds. But it’s also an element, and elements’ behaviors change depending on the molecules they belong to. It’s a cliche, but it’s true, so here it is: table salt is made of a metal that explodes when it touches water and the main ingredient in bleach. The deadliness of salt’s component elements has very little to do with whether salt is deadly or not. This is admittedly less true of arsenic — if you come across an arsenic compound, please refrain from putting it in your mouth! But it’s still true at least some of the time, and we’re not doing ourselves any favors by getting confused about it (the same varying inorganic/organic toxicity also holds for mercury, by the way, though in reverse).
Gansler’s appeals to uninformed intuition are suspicious and potentially dishonest. Like I said, I’m not anxious to eat any more Roxarsone. So how about an honest case for banning it?