Carisa brought to my attention a recent paper in the journal Environmental Health that details an inquiry into the mercury content of high fructose corn syrup, a ubiquitous food additive (fervently disliked by this blogger).  As the story goes, an Environmental Health Officer (EHO) at the FDA was trying to track down some missing mercury in the chlor-alkali industry starting in 2003.  During this process, the EHO learned that two products created by the chlor-alkali industry, sodium hydroxide and hydrochloric acid, could contain small amounts of mercury depending on the processes used in their manufacture.  The EHO then went on to discover that these two products were used mainly in the production of high fructose corn syrup (HFCS).  It wasn’t a huge leap of insight from there to surmise that mercury might, as a result, end up in HFCS and thus the country’s food supply.  Sure enough, government labs, followed subsequently by an independent lab, found mercury in HFCS samples.  The paper mentions that out of twenty samples from three production facilities tested by the independent lab, nine contained detectable amounts of mercury.  Of course, being smart people, your next question is how much?  The dose makes the poison, after all.  Well the range was 0.012 to 0.570 micrograms mecury per gram of HFCS, with an average of 0.252 micrograms Hg/gram HFCS.

Still need more info?  That’s the spirit.  The average American consumes about 50 grams of HFCS per day.  Revolting, isn’t it?  Taking the worst case scenario of 0.570 micrograms Hg/gram HFCS, that means 28.5 micrograms Hg per day just from HFCS.  The FDA lists 0.1 micrograms Hg/kilogram as a “no effect” amount of intake (note that this is a very controversial number, with different values almost everywhere you look).  So for a 70 kg person (high unlikely if you’re really consuming 50 grams of HFCS per day), that means you can safely shoot for 7 micrograms of mercury a day, or about a quarter of what you just consumed in all that HFCS.  Oops.  Just for reference, that six-ounce can of albacore tuna you just ate?  The stuff that you’re not supposed to have too often?  That’s roughly twice the amount of mercury from your HFCS.

Is there room for tighter standards and regulation here?  I think so.  For sodium hydroxide intended for food use, there is an international cap of 1 microgram mercury per gram of sodium hydroxide.  Unfortunately there is no such limit for hydrochloric acid.  At the other end of the food production chain, the FDA checks a lot of the food we eat for mercury, but unfortunately carbonated sodas – a huge source of HFCS – aren’t included on the list.

Now avoiding tuna and other yummy, high-mercury fish is difficult, especially since fish is generally good for you.  But luckily, avoiding this newly-recognized source of dietary mercury is not particularly challenging, at least from the culinary or health standpoints.  Avoiding HFCS means avoiding sugary sodas, over-sweetened breakfast cereals, and a lot of the highly processed, crappy excuses for food you find out there.  You’re not missing out on anything by cutting HFCS from your diet, and you’re probably doing yourself a great deal of good.  As if you needed another reason.