A study from Copenhagen found more than 400 different substances from bottle plastic, and more than 3,500 substances derived from dishwasher soap in reusable plastic bottles stored for 24 hours after being washed in a dishwasher (Journal of Hazardous Materials, to be published May 5, 2022;429:128331). The water stored in plastic bottles contained endocrine disruptors (Environ Sci Technol, 2016;50 (1):97-104), carcinogens (Packag Technol Sci, 2015;28(5):461-474), insecticides (Environ Health Perspect, Sep 2009;117(9):1368–1372), plastic softeners, antioxidants and release agents used in the manufacture of the plastic, as well as Diethyltoluamide (DEET), found in mosquito sprays. Many of the chemicals came from the dishwasher soap and the plastic bottles themselves because the dishwasher causes the release of these chemicals from the plastic.

The authors tested water left in bottles for 24 hours in bottles:
• both new and heavily used
• before and after machine washing
• after five extra rinses in tap water

My Recommendations
We do not know how toxic these chemicals are for humans because we don’t have adequate data, but we do know that plastic bottles themselves leech many different harmful chemicals into our water supply. Soaps used to clean dishes may be associated with damage to the intestinal lining to increase risk for intestinal disturbances (Science, Jul 22, 2016;353(6297):348-349). I recommend:
• Never heat foods or liquids in plastic containers
• Realize that storing drinking water or foods in plastic containers may be harmful
Personally, I try to use glass for drinking water and food storage.