Plastic cups taste 'dishwashery'

[Bails2014]

So yesterday, I was dying for a drink, remembered I had a toddler cup in the car (Advent 360), took a swig and EUGH, it tastes 'dishwashery'.

I've tried on a another one, given it a really good rinse under running water and it still tastes funny.

How on earth can I get them to stop tainting the water? I was thinking of soaking in water and bicarb and then just hand washing with no detergent in future? Help!

What tablets do you use?
We found anything lemon or citrus "scented" was a sod for this, more notably, the fairy burst things being the worst!
As soon as we switched to Ecover and Finish, no problem...
HTH

In using Fairy!

I find Finish are rubbish, they don't actually clean very well and my plastic always looks stained and glasses smeary.

I'll order some ecover and just use it to do plastic washes.

Fairy is the absolute worst for this. All our silicone utensils and plastic everything stank. We have switched back to finish and the smell and taste isn't as bad