The utility of silicone wristbands in characterizing exposure to parabens found in commercial lotions.

Silicone wristbands are increasingly used as a wearable exposure tool to assess inhalation and dermal exposure to semi-volatile organic chemicals present in indoor environments. However, little research has investigated their utility in detecting exposures specifically related to personal care product (PCP) use. Here, we assessed exposure to methyl-, ethyl-, and propylparabens after applying a lotion containing a known amount of each chemical. A convenience sample of 20 adults wore a wristband and collected all urine excreted for three days over two consecutive weeks, keeping their PCP use consistent. During one of these periods, participants were provided with a lotion containing a known amount of parabens and asked to apply it daily (4.57 g applied over three days, with one pump of lotion each day). Urine and wristband samples were extracted and analyzed for parabens via LC-MS/MS. Parabens present in the lotion were detected in 100 % of wristbands across both study periods, while urinary detection of these paraben ranged from 87 to 100 % across periods. Parabens were measured at higher levels in urine and wristbands collected during the lotion application phase. For every 10 % increase in wristband paraben concentrations, the total paraben mass excreted in urine increased an average of 4 % for methylparaben (95 % CI = 3-5 %, p < 0.0001), 4 % for ethylparaben (95 % CI = 3-5 %, p < 0.0001), and 6 % for propylparaben (95 % CI = 4-7 %, p < 0.0001). This study shows that wristband concentrations reflect differences in use of a PCP containing parabens. Differences in wristband concentrations between study periods were greater than differences in urinary biomarkers of exposure, possibly because wristbands represent total potential exposure from dermal and inhalation routes. As this investigation only required a difference of one pump of lotion applied daily, the sensitivity of wristbands to capture differences in PCP use is promising.