You’ve probably heard about arsenic making its way into food like rice, apple juice, or seafood, but it turns out wine can have high levels too. A new study published this week has methodically looked at the arsenic content of a variety of wines from locations around the country to see how they stack up region by region. In spite of confirming high levels of arsenic in some wines, the authors are cautious to note that the chances of that arsenic level having a real health effect is actually pretty low.
What is arsenic and where does it come from?
Arsenic is a heavy metal that occurs naturally in the environment and, as a result, is found at low levels in certain foods. Arsenic comes in several different chemical forms found in nature that change the chemistry and toxicity of this metal. These forms vary in their level of reactivity and amount of damage done to the body when eaten. One form, called arsenite, is considered the most toxic, while elemental arsenic and arsenate are considered less toxic. Even within these different forms of arsenic, the metal can come bound to several other chemicals that occur naturally, are made by animals who use arsenic for chemical reactions, or who have found ways to get rid of the toxic forms. These two additional types are called “organic” and “inorganic” arsenic and vary in toxicity. Arsenic can be found in drinking water in areas with high levels of arsenic in the Earth or in areas that use arsenic pesticides. While arsenic pesticides were banned in the U.S. in 2004, some residue can remain in the earth and leach into plants grown on the same soil. Other countries that export products to the U.S. may also still use these chemicals. Some fish and shellfish have naturally occurring high levels of arsenic, but in a form not thought to be dangerous.
What are the health effects of arsenic?
Arsenic toxicity normally causes a sudden severe illness if large amounts enter the body in a short amount of time. It can cause nausea, vomiting, abdominal pain, and severe diarrhea with other, more severe symptoms if the poisoning continues. Chronic poisoning over longer periods of time can cause patchy hair loss, a rash, ulcers in the mouth, and pain or loss of sensation in the arms and legs. It’s important to remember that while these are the most common symptoms of arsenic poisoning, there are many more common causes of these symptoms that need to be considered before arsenic poisoning is diagnosed. Once diagnosed, arsenic poisoning is fairly easy to treat and most of the symptoms are reversible.
What is a safe dose of arsenic?
As a result of the variety of types and sources of arsenic, it’s not enough to just think about the total level of arsenic in the foods a person is eating to figure out what the health effects might be. The arsenic found in some kinds of fish and shellfish, for example, hasn’t been found to cause any major toxicity. On the other hand, some foods grown using arsenic pesticides have been found to have more toxic forms of arsenic that may have health effects. Arsenic found in drinking water more often tends to be arsenic with higher toxicity potential. It’s for that reason that the U.S. government sets limits on the amount of arsenic that can be found in drinking water. The limits set for safety reflect what’s considered the total safe dose a person could have since low levels of arsenic don’t appear to have health effects. The limit is set as a concentration, or amount of arsenic per amount of water. The regulators look at how much drinking water most people are consuming and work backwards to determine what concentration of arsenic would have to be in the water to deliver a toxic dose at that amount. They then add on a safe margin to make sure that even someone drinking a lot of water would be safe.
Why do wines contain arsenic?
Previous isolated tests had found arsenic in some wines, so this study set out to see how often arsenic is found in wine, whether some regions have higher arsenic concentrations, and whether those levels are truly concerning for the American public. The study looked mostly at red wines because they’re made with the skin of the grape where arsenic levels are highest if present. The arsenic found in those grapes is absorbed from the soil and can come both from old pesticide residue that might remain in the soil and from groundwater that contains arsenic that might be used to water the vines. The team measured the concentration of arsenic in the wine and compared that to the levels considered safe for adults.
What did the team find?
The researchers found that arsenic levels varied from state to state, with the highest levels in Washington, New York, and California, and the lowest levels in Oregon. Lead was also present in low levels in more than half of the wines. The highest levels often exceeded drinking water levels, but the researchers wanted to know if that was really relevant to a person’s health. To do this, they estimated how much arsenic a person would typically get from the usual two to three glasses they might have over the course of an evening. They compared this to how much arsenic people get from other foods in their regular diet. The team found that the arsenic in wines usually makes up about a tenth of the total daily dose of arsenic for the typical person, in spite of its higher levels, because most people don’t drink large enough amounts of wine to overdose on arsenic. The biggest concern for arsenic levels in the tested foods turned out to be baby formulas, which can contain significant arsenic levels from organic brown rice syrups that can contain arsenic. In some cases, the dose was 10 times recommended.
Should I be concerned?
For most people, the amount of arsenic in wine poses no health threat. The fact that the levels are higher than those allowed for drinking water shouldn’t be of concern because most people drink much more water than wine and it’s the total dose of arsenic, rather than the concentration, that matters the most. The authors encourage those who are big wine drinkers to look at their diet as a whole. If you eat a lot of foods that can be high in arsenic, like rice or cereal bars, then you might think more carefully about your wine consumption. If you use baby formula that contains organic brown rice syrup, you should check the Internet for arsenic levels and consider switching brands if levels are high. If you’re concerned, have a conversation with your doctor about the amount of arsenic in your food and whether you should make changes to your diet to avoid toxicity.