the Scientific Research Committee - IslamToday.net
FD & C Yellow No. 5 is also known as tartrazine, C.I. 19140, acid yellow 23, filter yellow, food yellow 4, tartrazine C, among other names.
Its molecular formula is C16H9N4Na3O9S2.
It comes in the form of an orange powder that is water soluble. It is also available in a liquid or a granular form and is used both as a food coloring and a biological stain. It is a purely synthetic product, synthesized primarily from petroleum-based chemicals. It is not derived from animal sources.
Tartrazine (FD & C yellow No. 5) may cause allergic reactions including bronchial asthma in susceptible individuals. Although the incidence of tartrazine sensitivity is low, it frequently occurs in patients who are sensitive to aspirin. It is considered safe by the US Food and Drug Administration.
You should find out from this person why Muslims should not consume products containing tartrazine (FD & C Yellow No. 5). We can find no reason to declare such products unlawful.
Source: Islam Today