Atlanta Journal-Constitution: To maintain the effectiveness of hand sanitizer, Karen Dobos, Ph.D., a professor in the department of microbiology, immunology and pathology at Colorado State University, recommended to Health.com, that it’s stored at a temperature of 45 to 75 degrees Fahrenheit. While there have been concerns about keeping the product in a hot car, Health.com reported it should be fine to keep a small bottle in the center console or glove box as long as it’s not there all day when it’s warm outside.

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