I've heard others say they use bleach in their coolant. Is this a viable option or will it damage my mill please?

I'm machining plastics, aluminium and stainless and using a water soluable coolant (10% mix) cutting using a 1/2" 2 flute end mill.

My problem is that the sump stinks- like when you leave your clothes in the washing machine too long- that horrible "damp" smell.

Will bleach be ok to add?