ANSWER:

No problem in selling anyone halal products. It’s not your concern what they do with it afterwards. 

Im working in ice factory as sales man & sometimes shia customers come to buy ice for their mat’am to put in juice. Am i sinful for selling ice to them ? Im not owner of factory and working as salesman.

Halal/Haram Matters, Jobs | September 4, 2019 2:56 am
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While eating, if something gets stuck between our teeth , is it permissible to remove it n eat it back again? Because I heard it’s against the sunnah.
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My daughter is 4 months and I have just been told the routine vaccinations they give here (UK) contain pork gelatine. Would we need to have a blood transfusion or anything to cleanse? If needed to be cleansed. And if they are needed for really dangerous health threat is it allowed to be taken?