EOSINOPHILIA-MYALGIA-SYNDROME AND TRYPTOPHAN PRODUCTION - A CAUTIONARY TALE

An epidemic of a new disease, termed eosinophilia-myalgia syndrome, oc curred in the USA in 1989. This syndrome was linked to the consumption of L-tryptophan manufactured by a single company utilizing a fermenta tion process. All the findings indicate that the illness was probably triggered by an impurity formed when the manufacturing conditions were modified. This outbreak highlights the need for close monitoring of t he chemical purity of biotechnology-derived products, and for rigorous testing of such products following any significant changes to the man ufacturing process.