Recently I noticed that some of our glasses and cutlery had developed a blue-ish deposit as you can see for the two sets of spoons below. For each set the spoon on the left has the blue-ish deposit whereas the spoon on the right is the original.
I traced the cause of this blue-ish deposit to a specific effect. It only occurs when the spoon or glass has been used for a medicine called Questran-A, which is a powder that needs to be dissolved in water and then ingested. And more specifically, it only happens when these glasses/spoons are subsequently washed in our dishwasher.
This leads me to believe that some reaction occurs between the (left-overs) of the medicine and the dishwasher tablets. My question is: does anyone know what reaction between the chemicals in the medicine and those in the dishwasher tablets could cause this blue-ish deposit?
Obviously this will be impossible to say without the ingredients of both, so here is a list of the contents of the dishwasher tablets and the medicine:
Dishwasher tablets (Albert Heijn):
- pentasodium triphosphate
- sodium carbonate and sodium carbonate peroxide
- taed
- sodium silicate
- PEG-90
- alcohols, C16-18, ethoxylated mind 30 EO
- acrylic copolymer
- PEG-4
- maleic acid/acrylic acid copolymer,sodium salt
- alcohols, C12-18 ethoxylated propoxylated
- zinc sulfate
- beta-alanine, N-(2-carboxyethyl)-, N-coco alkyl derivs, disodium salt
- mn-complex
- benzotriazole
- subtilisin
- tetrasodium etidronate
- alpha-amylase
- benzisothiazolinone
- 4 mg colestyramine
- 30 mg Aspartame(E 951) equal to 17 mg Phenylalanine
- Citric acid(E 330)
- kelcoloïd
- Silicon dioxide(E551)
- Orange flavoring
- Xantham gum (E 415).