I spent six years working in the statistical modeling team at the UK’s Health and Safety Laboratory. A large part of my job was working with the laboratory’s chemists, looking at occupational exposure to various nasty substances to see if an industry was adhering to safe limits. The laboratory gets sent tens of thousands of blood and urine samples each year (and sometimes more exotic fluids like sweat or saliva), and has its own team of occupational hygienists who visit companies and collect yet more samples.
The sample collection process is known as “biological monitoring.” This is because when the occupational hygienists get home and their partners ask “How was your day?,” “I’ve been biological monitoring, darling” is more respectable to say than “I spent all day getting welders to wee into a vial.”
In 2010, I was lucky enough to be given a job swap with James, one of the chemists. James’s parlour trick is that, after running many thousands of samples, he can tell the level of creatinine in someone’s urine with uncanny accuracy, just by looking at it. This skill was only revealed to me after we’d spent an hour playing “guess the creatinine level” and James had suggested that “we make it more interesting.” I’d lost two packets of fig rolls before I twigged that I was onto a loser.
The principle of the job swap was that I would spend a week in the lab assisting with the experiments, and then James ...