The Food and Drug Administration (FDA) has recently performed a series of experiments into the relationship between arsenic and rice, the results of which indicates rice may not necessarily present the huge health risk that many initially feared. So, are we all no longer at risk, or should we remain skeptical?
Organic and Inorganic Arsenic
Arsenic is a ubiquitous chemical found in the environment, stemming from natural and manmade sources. Within nature, arsenic is released from volcanic eruptions and is found within certain rocks. Comparatively, a number of human processes can lead to arsenic contamination; dissemination of arsenic-containing pesticides and human mining operations have contributed towards this phenomenon, as has the smelting of ores and combustion of fuel sources.
FDA officials maintain, even if mankind’s contributions to environmental arsenic levels was subtracted from the equation, the toxic chemical would still contaminate our food chain, including rice and rice products.
Arsenic exists in two classified forms, organic and inorganic, which can be found within food, water, the earth and the atmosphere. Evidence seems to suggest that inorganic arsenic can result in long-term health effects.
Although the FDA have been scrutinizing the trace amounts of arsenic in our foods for quite some time, recent advancements in testing practices are set to yield data of even greater detail.
The FDA is seeking to alleviate the public’s perception over the growing threat over arsenic poisoning and rice. During a new set of guidelines, which was released to the public Sep. 6, the organization discussed its latest research efforts on the subject.
Taking over 1,300 test samples of rice, alongside a number of related products, the FDA conducted a thorough analysis of the “total arsenic” content, constituting both organic and inorganic forms of the toxic compound. Based upon their preliminary assessments, the investigated samples failed to contain sufficient quantities of arsenic to pose any harm to consumers.
Both organic and inorganic forms of arsenic are found within soil and water. As a consequence, growing crops become contaminated with arsenic, as they absorb the nutrients and water from arsenic-impregnated land.
Generally, this does not present much of an issue, as most crop types are unable to acquire or utilize arsenic, and it simply remains in the ground. However, rice is an entirely different matter. Rice uptakes arsenic with greater ease than most other grains, becoming tainted with larger concentrations of the dangerous chemical.
Suzanne C. Fitzpatrick, who works for the FDA’s Center for Food Safety and Applied Nutrition, briefly discusses the significance of arsenic-contaminated rice, as well as the logistical difficulty in protecting the general public:
“One of the things we need to emphasize is that arsenic is a naturally occurring contaminant, and because it’s in soil and water, it’s going to get into food… It’s not something that we can just pull off the market.”
Aside from rice, seafood is another potential source of arsenic. Comparatively speaking, however, seafood is conjectured to be less hazardous than rice, as it contains the organic form of arsenic.
Toxicity of Rice Grains and Products
Under a European Union directive, arsenic compounds are now officially classified as toxic, and may present considerable hazard to the environment. In addition to this, the International Agency for Research on Cancer (IARC) has categorized arsenic as a group 1 carcinogen.
During the FDA’s latest study, however, the average dose of inorganic arsenic identified within a serving of rice grains ranged between 2.6 to 7.2 micrograms. Interestingly, they correlated the concentration of arsenic per serving to different types of rice; brown rice was perceived to have the highest amount of arsenic, whereas instant rice contained amounts at the lower end of the spectrum.
Rice products demonstrated a lower range of inorganic arsenic (0.1 to 6.6 micrograms per serving). When looking for differences between rice products, the research team found infant formula to have the lowest amount of arsenic, whilst rice pasta had the highest amount.
A number of theories rage over the precise biological mechanism of toxicity. The general consensus seems to be that arsenic targets a particular organic compound, called thiols. These structures are often found inside the active sites of many enzymes, required for proper cellular function.
Arsenic poisoning also prohibits production of a universal energy carrier, called ATP, and can even generate highly damaging reactive oxygen species, leading to necrotic cell death.
Ultimately, with exposure to sufficient quantities of the chemical, the consequences can be devastating, resulting in multi-system organ failure and death.
Long Term Health Consequences & the Future
As admitted by the FDA, one of the glaring omissions in their research centers around the absence of information, regarding the long-term health consequences of eating rice. The FDA is still yet to determine whether the arsenic concentrations may have a cumulative effect when consumed over a period of many years.
Fitzpatrick indicates that more work is imminent:
“These are the next steps. To look at exposure levels, to analyze the risk, and determine how to minimize that risk for the overall safety of consumers, including vulnerable groups like children and pregnant women.”
The FDA also collected information about populations deemed to have been exposed to high levels of arsenic; these include groups of people from Bangladesh, Chile and Taiwan. Eventually, the research team aim to see whether a correlation exists between consumption of arsenic-laden foods and a variety of medical conditions, including cardiovascular disease, cancer and diabetes, as examples.
In a previous study, John Duxbury, who studies soil chemistry at Cornell University, specifies that that arsenic levels in the soil represent a potential “cause for concern.” In particular, Duxbury found high levels of arsenic in the rice samples grown in the south central of the United States of America.
Meanwhile, in a bid to reduce the amount of arsenic taken up by rice, researchers are attempting to design rice plants that do not absorb as much arsenic.
Ultimately, much more research needs to be conducted to establish whether we are all truly at risk from the trace quantities of arsenic, found in our supplies of rice and rice products. Hopefully, the FDA’s future studies will, one way or another, demonstrate whether rice is safe to eat on a long-term basis.
By: James Fenner