I just found out a food I eat has high levels of arsenic in it, but the manufacturers claim the vast majority of it is organic arsenic, not inorganic. Supposedly inorganic is 500x more dangerous than the organic forms.
I have heard of various rules like ‘10mcg of arsenic per liter of water’ being the max allowed by the government, but does that mean 10mcg of inorganic arsenic, or is there a mix? 10mcg of inorganic arsenic is not the same thing as 1mcg inorganic and 9mcg organic.
Is 10mcg a day of inorganic arsenic considered harmful?
Arsenic is an elemental metal; there is no such thing as “organic” or “inorganic” arsenic. However, if you’re talking about organic chemical compounds of arsenic (and here, “organic” just means compounds of arsenic that contain carbon atoms) then you’ll have to be more specific. There are many, many different chemical compounds that contain arsenic, and they can be dangerous in different ways or in different concentrations. I don’t know of any offhand that I’d call exactly safe, and the claim that “organic” ones are safer seems dubious. Many organic compounds of arsenic have been used, variously, as insecticides and chemical weapons. See the Wikipedia article on Organoarsenic chemistry for some examples.
Yeah, same answer, basically: somebody’s trying to make a distinction that doesn’t exist. “organic” and “inorganic” (in the chemical sense, not in the modern “more dangerous and more expensive” sense) don’t equate to “healthy” and “unhealthy”, even in compound with a specific element.
That said, chemical processes can certainly turn dangerous elements into non-dangerous compounds (Sodium and Chlorine being the classic example), but for a real answer you’ll need to actually tell us what the food is.
ETA: I’m told that arsenic levels in the body are pretty easy to test for; you might want to ask a doctor if you think you may have ingested too much of it, since it’s a cumulative poison.
Generally speaking, this is not a meaningful distinction. “Organic” is a technical term for a compound that contains a carbon atom, and “inorganic” refers to all compounds which do not. This is occasionally a useful distinction to make for chemists, but is essentially meaningless and arbitrary for any other purpose, and has essentially nothing to do with a compound’s chemical properties, toxicity, etc.
To evaluate toxicity, you would need to know the exact chemical compound. “Oh, don’t worry, our food might have arsenic, but it’s organic arsenic!” is major league BS, akin to saying that you are better off being shot with a certain type of bullet because it’s made of “organic lead”.
Arsenic is present in the environment as a naturally occurring substance and as a result of contamination from human activity, such as from the use of certain pesticides and fertilizers. It is found in water, air, food and soil.
There are two types of arsenic: organic and inorganic. The inorganic forms of arsenic are the harmful forms, while the organic forms of arsenic are essentially harmless. Because both forms of arsenic have been found in soil and ground water, small amounts may be found in certain food and beverage products, including fruit juices and juice concentrates.
Wow. Is that article a joke? I find it difficult to believe that site really written and maintained by the FDA. They’re peddling unscientific idiocy. Organic arsenic compounds include, among many other nasty poisons and pesticides, diphenylchloroarsine, which was used as a chemical weapon during World War I. The mind boggles that the FDA would say something as stupid as “the organic forms of arsenic are essentially harmless.”
Nobody who knows even the first thing about organic chemistry would say that.
I can only assume that article was written by an ignoramus who was using “organic” in its capacity as a meaningless feel-good buzzword.
I don’t think the FDA was referring to Arsenic compounds intentionally designed to be toxic, they were referencing naturally occurring organic arsenic compounds (or possibly industrial byproducts) which end up in the food supply.
Either way, I do not know which compounds are in the products I’ve used. I was just told the vast majority was an organic form of arsenic. However they didn’t say which one. I do not know if arsenic sugars or arsenic betaine are the most common organic forms or if there are other, more toxic versions.
The article distinguishes between naturally occurring and human introduced arsenic, somewhat clumsily described as “harmless organic” and “inorganic” respectfully. It is the naturally occurring arsenic compounds that are of little health concern, rather than the ones introduced as pesticides and fertilizers, which have potentially severe consequences.
While the there may be toxic arsenic compounds that are technically organic, this blog post uses “organic” colloquially rather than strictly chemically.
“Organic” and “inorganic” are real terms that real chemists use to describe arsenic compounds, and it is absolutely true that organic arsenic compounds tend to be relatively harmless compared to inorganic forms. One of the first things most organisms do to inorganic arsenic to protect themselves is methylate it.
Thanks. But does anyone know when it is said ‘X mcg of arsenic per liter of water is safe’ as a comparison, do they mean 100% inorganic arsenic? I really don’t know how it works.
If 10mcg per liter is considered the max safe dose, then if that is 10mcg of pure inorganic form then that is totally different than an organic form or a mix.
Figures. Badly written blog made more confusing thanks to the “organic” marketing term.
Anyway, the point is that many foods naturally contain a small amount of arsenic in a number of chemical species. Similarly, many places in the US (and the world) have naturally occurring higher levels of arsenic in the soil (and thus the water) than other places. This has caused issues as the EPA dropped the allowable level from 50 ppb to 10 ppb and several areas (mostly in the West) had to spend a lot of money to reduce the naturally occurring higher level of arsenic to this lower standard.Here’s a PDF from Sandia National Laboratories about New Mexico.
I suspect, but do not know for sure, that the 10 ppb standard is independent of the identity of the arsenic compounds and is probably determined by something like ICP-OES or ICP-MS. Not being an analytical chemist or a water chemist I could be wrong, but that’s how we’d look for heavy metals in pharmaceutical products, especially with the new ICH standard coming out to replace the USP heavy metals.
If it’s in drinking water it’s likely worse forms. If it’s in apple juice (a common source) it’s likely much less bad. The chemistry is pretty complicated. For instance, rice has lots of arsenic. But how much and exactly what form it’s in can vary significantly based on something as simple as how the rice is irrigated (e.g. flooding vs spray). Even just leaching from rock into drinking water is complicated. This is a very nice review of the chemistry, http://dx.doi.org/10.1021/cr00094a002 , but it’s paywalled.
What it comes down to is that describing arsenic safety concerns is hard to do in one sentence. IIRC the drinking water limits assume worst-case naturally occurring arsenic oxides that don’t always translate well to food.
Interestingly, in the case of mercury, organic mercury compunds are often far more toxic than elemental (“inorganic”) mercury metal. Dimethylmercury is an extreme example.
For that kind of levels, yes. For higher levels you can go old school and use titration, but at those… spectrometry is the way to go. Pharma and “plain ol’ chemistry” aren’t going to be using different analytical techniques.
Well, that’s what I figured, but I wanted to hedge. I’ve never run an ICP of any kind and don’t expect to in the future. I couldn’t see how the technique would be incompatible with a water sample but wasn’t sure. For me these days analytical chemistry is submitting a sample to the analytical department and then having to harass the analyst to hurry up and give me the results already. (An exaggeration to be sure, but believe me, I’m not running metals analysis in an organic lab.)