Drinking water safety in Tibet

No, the drinking water is not safe in Tibet.
The safety of drinking water in Tibet has been bothering rural Tibetans in Tibet's remote farming and pastoral areas. But Tibet Autonomous Region will strive to completely resovle the problem of drinking water safety by 2013.
At present, if you plan a trip to Tibet, here we would like to share some Tibet travel advice on drinking water.
1. Drinking water in Tibet should be purified with iodine or other purification tablets to prevent intestinal complaints. 
2. Do not to eat any vegetables or fruits that have not been cooked, because they would have been washed (or not) with the local water.
3. You'd better use bottled water from larger stores. Or you can boil tap water before drinking it, but be aware that at Tibetan altitudes it needs to be boiled for 10 - 20 minutes in order to kill all pathogens for the lower air pressure makes for lower boiling points.
4. As the tea and water for thermoses is normally kept boiling over a fire until it is needed, it is normally safe. The thermoses with boiled water you will find in hotels and guesthouses are also safe.
5. Do not to drink alcohol until acclimated, or we'd get a headache for the rest of the trip
6. You'd better brush your teeth with bottled water.