Ruth Chepngetich, the women's marathon world record holder, is provisionally suspended for a positive doping test. Athletics Integrity Unit (AIU) said Chepngetich was tested positive for a banned diuretic hydrochlorothiazide (HCTZ) in March. Used as a masking agent, HCTZ has a minimum reporting level of 20 nanograms per millilitre (ng/mL) in urine but Chepngetich’s sample showed 3,800 ng/mL.