A study led by Tulane University recently found that some commonly consumed beverages contain levels of toxic metals that exceed federal drinking water standards. The study was conducted to fill knowledge gaps, as there are few peer-reviewed studies examining the contents of U.S. beverages.
A total of 60 beverages were tested in the study, five of which contained levels of a toxic metal above federal drinking water standards. Additionally, two mixed juices had levels of arsenic above the 10 microgram per liter (μg/L) standard. A cranberry juice, a mixed carrot and fruit juice and an oat milk each had levels of cadmium exceeding the 3 parts per billion (ppb) standard.
The sampled beverages included those commonly found in U.S. grocery stores—single and mixed fruit juices, plant-based milks, sodas, and teas. The samples were measured for 25 different toxic metals and trace elements. Mixed-fruit juices and plant-based milks (such as oat and almond) contained elevated concentrations of toxic metals more often than other drinks.
Overall, seven of the 25 tested elements were found at levels above drinking water thresholds in some of the drinks, specifically, nickel, manganese, boron, cadmium, strontium, arsenic, and selenium. While lead was detected in more than 93 percent of the 60 samples, most contained very low levels, below 1 ppb. The highest level—6.3 μg /kilogram (kg)—was found in a lime sports drink, although still at levels below both EPA and WHO standards for drinking water.
Soft drinks, such as those included in the study, are often consumed in smaller quantities than water, meaning the health risks for adults are most likely low. The study’s authors warn, however, that parents should be cautious about what drinks they offer their children, advising parents to avoid giving infants and young children mixed-fruit juices or plant-based milks at high volume. Although naturally present in the environment, toxic metals such as arsenic, lead, and cadmium are known carcinogens and can cause internal organ damage and cognitive harm in children.
The researchers’ next step is to conduct a risk assessment based on the data collected to see the impacts of consuming toxic metals in children and adults.