That may seem obvious to some but, according to the new CDC report, in May and June, there were 15 cases of alcohol poisoning “associated with swallowing alcohol-based hand sanitizers. Four patients died, and three were discharged with visual impairment.” And it’s one specific kind of alcohol-based hand sanitizer that’s causing these problems, the CDC notes. Hand sanitizers should only contain ethanol or isopropanol. (To be exact, according to the CDC, your hand sanitizer should contain at least 60 percent ethanol or at least 70 percent isopropanol.) However, in the past month, the U.S. Food and Drug Administration (FDA) has issued warnings that over 100 specific hand sanitizers available in U.S. are labeled as containing ethanol but are actually found to contain methanol, a toxic chemical that can poison people through their skin or even cause death if ingested. “Methanol is not an acceptable active ingredient for hand sanitizers and must not be used due to its toxic effects,” the FDA said in a statement. All 15 patients cited in the CDC report had methanol poisoning. “This investigation highlights the serious adverse health events, including death, that can occur after ingesting alcohol-based hand sanitizer products containing methanol,” the report states. Exposure to hand sanitizer that includes methanol can result in “nausea, vomiting, headache, blurred vision, permanent blindness, seizures, coma, permanent damage to the nervous system, or death,” according to the FDA.ae0fcc31ae342fd3a1346ebb1f342fcb The CDC adds that “survivors of methanol poisoning might have permanent visual impairment, including complete vision loss.” RELATED: For more up-to-date information, sign up for our daily newsletter. A CDC spokesperson further explained the warning to CNN, saying: “We wanted to specifically look at adverse events related to methanol because it is known to be toxic and potentially life-threatening when ingested.” Following the FDA’s lead, the CDC also notes in their report that “health departments in all states should coordinate with poison centers to identify cases of methanol poisoning.” And for more on hand sanitizers, check out You Haven’t Been Rubbing in Your Hand Sanitizer Correctly, CDC Says.