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.
Brushing your teeth too soon after meals can seriously damage them, warn dentists. Many people brush more than the recommended number of times per day - especially after a rich meal. But dentists warn that the extra brushing could be doing more harm than good. Brushing within half an hour of eating a meal or drinking a cup of coffee could ensure your teeth suffer worse damage. After drinking fizzy or acidic drinks, the acid burns into the enamel of your teeth - and the layer below the enamel, called 'dentin'.