Bottled water is often considered the safest choice for avoiding drinking-water contaminants like arsenic and lead, but a recent spate of investigations has found that not all of it is free of potentially toxic chemicals.

In June, testing from the Center for Environmental Health found “high levels” of arsenic in bottled water brands owned by Whole Foods and Keurig Dr Pepper. Their findings confirmed earlier research from Consumer Reports, which found levels of arsenic that exceeded the allowable limit set by the FDA.