Interesting but I guess the key here is that they sprayed something stretched with water. I'm not an essential oils person but I'd guess a pure oil would kill all bacteria.
So I'd suggest better not to buy sprays, rather buy pure stuff and use a diffuser.
I was trying to find information about lavender cancer causing properties and instead stumbled on this contaminated aerosol:
https://www.nbcnews.com/health/health-news/lavender-spray-wa...