Disposal of used HRT patches and oestrogel pumps

Hi everyone

I'm doing a bit of fact finding on disposal of HRT products. 

The UK patient information leaflets for HRT patches state the following:

Peel an edge of the patch smoothly away from the skin • Fold the patch in half, so that the sticky side sticks to itself • Put it in with the household rubbish, safely out of the reach of children and pets • Do not flush used patches down the toilet.

The UK patient information leaflets for Oestrogel pumps state the following:

Do not throw away via wastewater or household waste. Ask your pharmacist how to throw away medicines you no longer use. These measures will help protect the environment.

Is anyone aware of any research or data on what evidence there is on the safe disposal of these products, and what evidence there is on their impact on pharmaceutical pollution. Also any other work that may have been done in this area, particularly any research into what patients actually do with these products? What advice is given on disposal of these products in other countries?

Very grateful for any information, so thank you in advance!

Nuala