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).
But there was another clue: when he started working from home, it got better.
But despite this things seemed to just be getting worse until the day we went into lockdown. With weeks my skin massively improved. Occasionally it would still go a bit bad but in those early days of the pandemic my skin was better than it had been for years. I didn't understand it but I wasn't complaining! Then as the world started to reopen I started going out more and my skin gradually got worse again. This was particularly true when I returned to the office after a year and half last autumn. Suddenly I was back to square one, in fact, it was worse.
Turns out it was those godawful workplace air fresheners that automatically blast cheap industrial perfume every few minutes. Tssst! Tssst! Tssst!
An amusing coda: Hayward is an editor at the newspaper that published the story, so it's no wonder his employer very promptly got rid of the workplace allergen!