Re: can the ingredients in deoderant cause breast cancer?

I'm unaware of any links between breast cancer and deodorant, however, the 
question you really want to answer is "does aluminium cause breast 
cancer?". If it does then you need to see if it is present in deodorant. If 
it is you then need to see if the levels in deodorant are high enough to be 
likely to lead to cancer. Go to  http://www.ncbi.nlm.nih.gov/entrez/query.fcgi and search various words 
(cancer and aluminium is a good start) it will provide you with research 
that has been published and should answer the question of whether 
aluminium causes cancer and at what concentrations it is likely to be 
detrimental to health. Once you've found that out you'll have to do some 
detective work to see if aluminium is present in deodorant. This may be 
written on the side of the can, but you'll have to check if it is 
compulsory for manufacturers to provide such information. There are various 
techniques you can do to test for aluminium, I'd ask your chemistry teacher 
to see what is available to you. Once you have found out how much aluminium 
is present in deodorant you will be in a position to conclude whether it 
may be a risk to consumers.
Good luck.
Chris Ward