In a fascinating story, Will Hayward explains his years-long effort to figure out what was causing constant skin rashes on his face, from the "false dawn" of rosacea to gruelling allergy strip tests that revealed the true culprit: methylisothiazolinone. Methylisothiazolinone is found in many consumer and industrial products and is controversial because of its allergenicity, which leads to stories like this (and maybe to the vast array of other names behind which its presence hides). — Read the rest
