Occupational Exposure Limits. The amount of toluene that a worker breathes over a work day is determined by the concentration in air, and the length of time the worker is in that atmosphere.Enforceable limits in the United States for the concentration in air have been established by Federal OSHA.he amount of toluene that a worker breathes over a work day is determined by the concentration in air, and the length of time the worker is in that atmosphere.
At night, your mouth is much less active, which allows bacteria more time to grow without being mechanicalyl sloughed off. Many years ago my orthodontist told me that it was most important to brush your teeth before going to sleep (I guess either for the night, or for a nap). Saliva production is down, and if you happen to sleep with your mouth gaping open, your teeth dry out and don't have that protective layer of saliva.
In order to really see the results from brushing your teeth, you need to brush for 2 minutes each time you brush, or 120 seconds. To reap the full benefits of brushing your teeth you need to brush once in the morning and once in the evening before going to bed.