If you use high chemical content cleaning materials, Sonia, then I would not recommend using any of it on the garden.
If you change your shopping habits and buy organic products, we tend to buy Ecover but it is not the only one, Then you should be able to use any of your household 'grey' water in the garden without worry.

Same applies to shower gels, you can get mild eco versions of those - shampoo's more difficult, any eco type shampoos don't do the job properly as far as I'm concerned, so I wouldn't use that water on the garden. On the other hand, if the garden's desperate, using that water just occasionally should be okay, but I wouldn't put it on anything sensitive or edible, and particularly not in pots.

As B says if you use organic shampoo, shower gel, washing up liquid etc these will not affect your garden, otherwise you are putting a build up of chemicals in the soil.