E. Coli can die under the following conditions –
1. High temperatures above 70 degrees Celsius.
2. Dessication – i.e. subjecting them to dry air which is hot.
3. Both Ionizing and Non-Ionizing radiations.
4. High pHs.
5. Anti-bacterial chemical agents for e.g. salts, sugars, ethanol, formaldehyde, chlorine, etc.
6. Usage of antibiotics.
These conditions can be both natural or induced.
https://www.quora.com/How-do-E-Coli-bacteria-die/answer/Rituparna-Saha-1