If so, what kind of bleach please? And what brand of washing machine? Any problems I should know about? I've got white cotton towels only they are really dingy. There's nothing wrong with them apart from the fact they've gone grey a bit. Before people come galloping to tell me I shouldn't put colours in the white wash: I don't. Said towels are about 10 years old, but they do not need replacing. I just want them nice and bright again.