CHEM 181 Chapter : woc 13- colouring with food dyes.docx

• School: McGill University
• Department: Chemistry
• Course: CHEM 181
• Professor: David Harpp

Document Summary

Story of purple kool aid, which contains both blue and red food dyes. The blue colouring reacts with yellow pigments in bile to produce green stool. Food dyes have been associated with hyperactivity in children, bronchospasm in asthmatics and cancer in rats. Para red and sudan i-tainted products in the uk; the two dyes are illegal because they have been shown to be carcinogenic in animals. Risk to humans was small, but it was not comforting. The possibility of adverse reaction cannot be ruled out. Up to 20% of patients with asthma are sensitive to aspirin and suffer acute bronchospasms, swelling and hives upon exposure: roughly 10% of these people are also sensitive to tartrazine and have to be careful to avoid it. In the 1970s, benjamin feingold, a california pediatrician, raised the possibility that certain food additives can cause hyperactivity in children: some parents gave evidence, and now british researchers have found scientific evidence for the additive-hyperactivity connection.