How do you obscure a members email address?

actually it is the standard theme, but I could not see an option.
To expand the topic title: after I have bulk uploaded member email addresses buddypress gives user names as their email address. When I investigated this originally I was led here and I joined as you had all the answers and I was able to fix it so that it at least worked. Now I can see I have the problem of displaying their email addresses that seems to occur by default. When I look at the underlying database, it seems to the column username, whihc I can edit for them to reduce down to their say firstname. Except that they would not know what I have done and I think this would lead to some confusion.

I read elsewhere that there is a spambot command but I cannot find that now and I was not sure how to use it?