Prevent food poisoning and waste. For example, nano sensors in food packaging could soon tell you if food was exposed to sunlight and therefore degraded in quality.
https://thenextweb.com/syndication/2019/08/24/nanotechnology-promises-to-revolutionize-global-nutrition-but-it-might-be-dangerous/
https://thenextweb.com/syndication/2019/08/24/nanotechnology-promises-to-revolutionize-global-nutrition-but-it-might-be-dangerous/