Does consuming Vitamin C after eating shrimp result in death by arsenic?

Question

I get lots of spam from family and friends, but this one in particular called my attention. It claims that if you eat shrimp and the ingest anything with Vitamin C, in a short period of time you would die from arsenic poisoning. A quick google search pointed me to these articles:

Hoax - Eating Shrimp and Taking Vitamin C Can Cause Death by Arsenic Poisoning

Shrimp, Vitamin C and Arsenic

Diet rumors in 2012: Prawns + vitamin C= eating poison?

Although they all say (more or less) that this is an urban myth, and I'm very inclined to believe them, only the second article points to a possible source of confusion, and none of them to a study that debunks the myth.

Does anybody know of any reliable source that points to a scientific study that disproves this hoax?

Answer 1

Possibly, but not likely

There is an older study mentioned in this 1985 Chicago Tribune article that states that and extremely high dose of Vitamin C followed by eating shrimp may result in "trivalent arsenic" being converted from the compounds in shrimp. "What the Illinois researchers found is that high doses of vitamin C convert the pentavalent compounds into trivalent arsenic, a highly toxic poison."

Unfortunately, I can not find the original study. Other "doctors" have gone on the internet to basically state that while it's possible, that the amounts of shrimp and vitamin c that would need to be ingested would be prohibitive, and even then arsenic poisoning would not cause "instant death" but may cause stomach aches, headaches, and the like. Essentially you would have to eat absurd amounts of shrimp and take huge amounts of vitamin c for a prolonged period of time, then it may be possible to die from it.

On the other side of the coin, there are two studies I have found that mention the effect of Vitamin C (amoung others) on reducing the toxicity of arsenic.

• counteracting chronic arsenic toxicity
• A Cancer Therapy Odd Couple: Vitamin C and Arsenic Trioxide

So while possible to cause long term arsenic poisoning by eating huge amounts of shrimp and massive amounts of Vitamin C, short term, deadly arsenic poising is not possible.