Posted on July 30, 2013 by Michael Rodburg
Earlier this month the FDA proposed an “action level” of 10 ppb for inorganic arsenic in apple juice (down from 23 ppb), bringing it to the same level as EPA’s drinking water MCL. One may view this action as the culmination of a campaign of sorts initiated by a 2011 Consumer Reports article whose cause was taken up by Dr. Oz. Yet, the FDA has been monitoring arsenic levels for many years and has never viewed the data as any cause for concern. Should we now believe that the FDA has made us completely safe by adopting a drinking water standard for juice? In a practical sense, yes, but in EPA-Superfund speak, not really; and that is the point of this post.
The poisonous propensities of arsenic have been the stuff of history and literature for centuries; the Poison of Kings and the King of Poisons. Remember elderberry wine from Arsenic and Old Lace? But, arsenic is, after all, not only naturally occurring but rather ubiquitous. The human race has managed to live with some level of arsenic for a few millennia now without evident consequence. Indeed, because of naturally occurring arsenic in groundwater in the western United States, the MCL is actually set “considering cost, benefits and the ability of public water systems to detect and remove contaminants using suitable treatment technologies.” If, in contrast, one turns to the gold-standard of “safe,” the one in a million excess cancer risk level, the drinking water standard required is .02 ppb; that’s right folks, 500 times lower than the current MCL and FDA’s proposed new juice level.
What does it mean? I think it points out that the ultra-conservatism of the “10 to the minus six” environmental risk standard leads to absurd results and hugely unnecessary costs. I still recall with a smile a quite notorious Superfund site (which shall remain nameless to protect a client) that had literally dozens and dozens of polysyllabic chemicals at high levels in soils, groundwater and waste disposal units throughout several hundred acres. In the baseline risk assessment, the only risk to exceed the 10-6level was that from naturally occurring arsenic in the soil!
The more we know about the genetic basis and causes of cancer, the more we realize how poorly both our animal models and in vitro experiments perform in predicting cancerous effects. (See E. Topol, The Creative Destruction of Medicine (Basic Books 2011) for a good discussion of the limitations and frustrations of our current methods and models for finding cancer fighting drugs.) While we are a long way from tossing EPA’s current approach to carcinogenic risk, we should perhaps take into account far more than we do now the inherent limits of our understanding and incorporate more the practical necessity for “cost, benefits and the ability” to “remove contaminants using suitable treatment technologies.” And yes, my grandchildren will continue to drink their apple juice.