Studying a small number of physicians and nurses at two hospitals, one that used triclosan-based soap and one that used plain soap and water, researchers funded in part by the Natural Resources Defense Council have found that the use of “triclosan-containing antibacterial soaps in health care settings represents a substantial and potentially biologically relevant source of occupational triclosan exposure.” Julia McIsaac, et al., “Health Care Worker Exposures to the Antibacterial Agent Triclosan,” Journal of Occupational and Environmental Medicine (2014).

Measuring urine triclosan levels in the study participants, the researchers found a geometric mean total concentration of 92.92 ng/mL for the exposed and 36.65 ng/mL for the unexposed hospital subjects. This compares with a 15.5 ng/mL geometric mean total urine triclosan level in 2009-2010 NHANES adult participants. Acknowledging the study’s shortcomings, including that the use of triclosan-containing toothpaste by participants in the triclosanfree soap hospital “obscured the differences between the two hospitals,” the authors suggest that further biomonitoring studies take place with a larger sample size of randomly selected individuals to confirm their results. Still, because they assert that some laboratory research has associated triclosan exposure with adverse health effects, and the chemical may contribute to antibiotic resistance and is biopersistent in the environment, the authors suggest that precautionary measures be taken.