Ding, Dong, Another Scare, Another Scare*
[*sing to the tune of The Witch is Dead]
Invited Post by John Nail, Ph.D.
On his September 14 show, Dr. Oz apparently claimed that apple juice contains large amounts of arsenic, making it unsafe for consumption, particularly for children. Previously, Dr. Oz has made claims about ‘unsafe’ amounts of contaminates in drinking water. While making claims of ‘____ (fill in the blank) is dangerous, we must protect the children from ____ (fill in the blank)’ may make for good daytime television, these claims are lousy science. Unfortunately, the typically American combination of poor thinking skills, pathetically poor science understanding and the ‘evil big business’ news story template make many people susceptible to accepting the scientifically unsupported, sensational claims made by entertainers such as Dr. Oz. Physicians such as Dr. Oz, a heart surgeon, rarely are scientists.
Yes, chemists can detect arsenic in apple juice; we can also detect arsenic in drinking water (both tap and bottled) and virtually every food, both ‘organic’ and conventional, in any supermarket, including Whole Foods. This ability to detect arsenic isn’t due to wide-spread arsenic contamination, it is more due to the incredible technology that allows Analytical Chemists to detect increasingly minute levels of chemical substances. Nowadays, we can almost always find any of the ‘bad’ substances in almost every food. The real issue is that minute amounts of bad substances are not necessarily harmful.
Decades ago, (real) scientists argued over the competing ‘Linear’ vs ‘Threshold’ hypotheses regarding exposure to toxic substances and exposure to radiation. Today, now that we can find almost every naturally-occurring toxic substance in everything, we’ve learned that the body has natural mechanisms for removing toxic substances and repairing damage from toxic substances. The ‘Threshold’ model, the assumption that permanent damage only occurs when the exposure happens faster than the body can fix things, is now widely supported. The ‘Linear’ model, in which it is assumed that any amount of exposure to a bad substance will cause some permanent damage, is only supported by government regulatory agencies, activist scientists and scientists whose scientific careers have been based on researching the effects of very low exposures. We’ve known for five centuries that ‘the dose makes the poison’, which means that everything (including water) is toxic in high enough amounts and nontoxic in low enough amounts.
Small amounts of arsenic (and other ‘bad’ substances, including radiation) are in our food and water because nature put them there. As an example, much of the soil in central Oklahoma contains naturally high amounts of arsenic.
Consider someone who lives in central Oklahoma and has high arsenic soil in their backyard. If an apple tree grows in the high arsenic soil, the apples produced by the tree will contain high amounts of arsenic, even if the tree is grown using ‘organic’ techniques (only chemicals produced by nature are used for fertilizer or pest control). The person who consumes the apples from the tree will be exposed to arsenic.
The Federal Government (EPA) set a limit of no more than 10 ppb (parts per billion) of arsenic for drinking water and mandates that the water in every municiple water distribution system be tested at least once every calendar quarter to measure the levels of ‘bad’ substances such as arsenic and chloroform. Operationally, no water distribution system would let water with an arsenic level of above 9 ppb go into the system; this ensures that the water stays below the 10 ppb level. One part per billion of arsenic in water (or apple juice) is 0.000001 gram of arsenic in one liter (effectively one quart) of water or apple juice. Water with the federally allowable limit of 10 ppb of arsenic contains 0.00001 gram of arsenic in each liter of water.
Dr. Oz claimed to have found as much as 23 ppb of arsenic in apple juice. The Federal Government (USDA and FDA) also monitors the amounts of ‘bad’ substances, such as arsenic in food. While the USDA and FDA don’t set absolute limits as does the EPA, they would be ‘concerned’ about apple juice that contained 23 ppb of arsenic; when the FDA test food products, they rarely find arsenic levels higher than 13 ppb. (http://www.medicinenet.com/script/main/art.asp?articlekey=149396 ).
The USDA classifies a ‘serving’ of apple juice as one cup. Consider a child who drinks four cups of apple juice every day for ten years and that all of the apple juice that she drinks contains 23 ppb of arsenic. During this ten years, she would ingest a total of 0.083 grams of arsenic and 1,708,200 calories from the apple juice; 14,600 juice boxes would go to the landfill.
Some of our ancestors had to hunt wild animals and gather wild plants to keep from starving. Occasionally, instead of eating the wild animals, the wild animals ate them. Other ancestors had the relative comfort of being able to sometimes grow some of their own food. If the crop didn’t make, they often didn’t eat. Today, food more abundant and safe less expensive as it every has been during the history of mankind.
It appears that some people need something to worry about and Dr. Oz, as well as other entertainers, make a living by making mountains out of anthills.
DR. NAIL is Chair of the Chemistry Department at Oklahoma City University
