Is it safe to reuse loose tea leaves the next day? What precautions need to be taken for storing tea for reuse? I'm a fan of green tea and I find myself reusing the tea leaves 2-3 times a day. Sometimes I'll just store the leaves and reuse them the next day but it got me thinking if what I'm doing is actually "safe", I know that the taste isn't the same.

So my questions are:  


What's the best way of storing tea for reuse? Currently I drain the leaves and put them in a small sealed glass jar.  
Is it safe to store tea to reuse the next day? Bonus point for an actual reference/research proving that it has bad or no side effects whatsoever.
Here in China, it is normal to reuse tea again and again. Typically the first cup from the tea is bitter. Chinese people commonly pour one cup and then throw it away and drink the second cup from the same leaves. Workers here can be seen with a large mug or jar of tea. When drunk, they top up the water again with hot (but not boiling) water. This will go on all day.

The next day, however, they will not reuse the tea. My Chinese wife always tells me off if I reuse the previous days tea leaves. She says they are bad for you, though I have never had any problem myself.