Home Made fly repellent

Not sure what else you are putting in but the "recipe" I use says I mug of cold strong tea and 4 tablespoons of vinegar. I have never experienced a bad reaction and have used this for years.
 
For my home made fly spray I use the Avon Skin so Soft dry oil body spray 1/2 a bottle of cider vinegar and top up to litre with cold tea.

Not had a reaction with it
 
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