The recent discovery by the FDA of high levels of arsenic in rice makes it likely we’ll soon be hearing more about excessive levels of the same potentially hazardous substance in dog food, too.
Arsenic is a toxic chemical found naturally in the environment — in soil and groundwater.
In humans, arsenic is known to cause:
- Bladder cancer
- Lung cancer
- Skin cancer
- Liver cancer
- Kidney cancer
- Prostate cancer
Arsenic is listed by the International Agency for Research on Cancer as one of over 100 substances classified as Group 1 carcinogens.
In medicine, a carcinogen is any cancer-causing compound.
How Arsenic Gets Into Rice
Arsenic can be found naturally in the environment. Yet it can also be found in higher concentrations in some plants — like rice — as the result of years of human agricultural activity.
There are many ways the chemical can find its way into the public food supply.
For example, until the 1980s, arsenic-based pesticides were commonly used by cotton farmers to help control boll weevils and other insects.
However, since then, many of these same cotton fields have been flooded with water to grow rice. So, some of the arsenic found in the soil is steadily absorbed by the growing rice plants.
What Kinds of Rice
Contain the Most Arsenic?
Testing by Consumer Reports1 found consistently higher levels of arsenic in the usually healthier brown rice than in white rice. That’s because the toxin tends to concentrate in the outer layer of the rice grain.
What’s worse, that same report also concluded:
“Arsenic concentrations found in the bran that is removed during the milling process to produce white rice can be 10 to 20 times higher than levels found in bulk rice grain”
Could Tainted Rice Affect Your Dog?
We think so. And here’s why…
In a study of 3,633 human subjects, Consumer Reports found:
“People who reported eating one rice food item had total urinary arsenic levels 44 percent greater than those who had not, and people who reported consuming two or more rice products had levels 70 percent higher than those who had no rice”
This would suggest that a dog eating the same rice-based recipe on a continual daily basis would likely have an elevated level of arsenic in its body, too.
‘No Adverse Effects’
In that FDA memo, an independent study was cited which found the highest amount of arsenic discovered in 58 pet food samples was just 4.2% of the maximum tolerable level for arsenic.4
Reassuringly, that same report concluded:
“Thus, no adverse effects due to arsenic are expected from consumption of these 58 pet foods.”
What Keeps Us Up at Night
Although a safe upper limit for drinking water has been established at 10 parts per billion, there are currently no Federal standards for arsenic in most foods.
Yet this situation may soon be about to change.
Since the FDA has recently discovered arsenic in many rice-based infant formulas, it’s quite likely the Agency will soon set limits for many human food products.
However, if the government does not set a limit for arsenic in pet food, the potential problem could get worse for dogs.
That’s because it’s a good bet much of that tainted rice banned for use in human food will somehow — like so many other rejected ingredients — end up in commercial pet food.
The Bottom Line
Since Consumer Reports5 has recommended “babies eat no more than one serving of infant rice cereal per day”, we feel compelled to suggest animal caretakers remain cautious, too.
Yet one independent report just cited here implies the amount of arsenic in pet food is expected to cause no adverse effects.
What’s more, some rice ingredients contain little (if any) arsenic.
So, what should we do?
Until the FDA completes its ongoing investigation and establishes a safe upper limit for the arsenic content of rice, dog owners may wish to limit the amount of rice they feed their pets.
- Consumer Reports Magazine, September 2012 ↩
- Target Animal Safety Review Memorandum, June 15, 2011 ↩
- National Research Council. 2005. Mineral Tolerance of Animals Second Revised Edition. Washington, D.C.: National Academy Press ↩
- Atkins P, Ernyei L, Driscoll W, et al. 2011. Analysis of Toxic Trace Metals in Pet Foods Using Cryogenic Grinding and Quantitation by ICP-MS, Part I. Spectroscopy. 26(1):46-56 ↩
- Consumer Reports Magazine, November 2012 ↩