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Cocamidopropyl betaine is a pseudo-amphoteric zwitterion
detergent derived from long-chain alkylbetaines. It is available
from many suppliers under more than 50 trade names
(including Tego-betain L7 and Ampholyt JB 130). Exposure
occurs via rinse-off products such as liquid soaps, shampoos,
and shower gels, but also via leave-on products (for
example, roll-on deodorant). Occupational sources are
mainly in hairdressing. The first synthesis step consists of
the reaction of coconut fatty acids with 3-dimethylaminopropylamine,
giving cocamidopropyl dimethylamine. This
amido amine is converted into cocamidopropyl betaine by
reaction with sodium monochloroacetate. Both dimethylaminopropylamine
and cocamidopropyl dimethylamine
are thought to be the sensitizers.
