Crossover Control Study of the Effect of Personal Care Products Containing Triclosan on the Microbiome.
Commonly prescribed antibiotics are known to alter human microbiota. We hypothesized that triclosan and triclocarban, components of many household and personal care products (HPCPs), may alter the oral and gut microbiota, with potential consequences for metabolic function and weight. In a double-blind, randomized, crossover study, participants were given triclosan- and triclocarban (TCS)-containing or non-triclosan/triclocarban (nTCS)-containing HPCPs for 4 months and then switched to the other products for an additional 4 months. Blood, stool, gingival plaque, and urine samples and weight data were obtained at baseline and at regular intervals throughout the study period. Blood samples were analyzed for metabolic and endocrine markers and urine samples for triclosan. The microbiome in stool and oral samples was then analyzed. Although there was a significant difference in the amount of triclosan in the urine between the TCS and nTCS phases, no differences were found in microbiome composition, metabolic or endocrine markers, or weight. Though this study was limited by the small sample size and imprecise administration of HPCPs, triclosan at physiologic levels from exposure to HPCPs does not appear to have a significant or important impact on human oral or gut microbiome structure or on a panel of metabolic markers. IMPORTANCE Triclosan and triclocarban are commonly used commercial microbicides found in toothpastes and soaps. It is unknown what effects these chemicals have on the human microbiome or on endocrine function. From this randomized crossover study, it appears that routine personal care use of triclosan and triclocarban neither exerts a major influence on microbial communities in the gut and mouth nor alters markers of endocrine function in humans.
Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York, USA; Department of Microbiology, Cornell University, Ithaca, New York, USA.
Angela C
AC
Poole
Department of Medicine, Stanford University School of Medicine, Stanford, California, USA.
Lauren
L
Pischel
Department of Medicine, Stanford University School of Medicine, Stanford, California, USA.
Catherine
C
Ley
Department of Medicine, Stanford University School of Medicine, Stanford, California, USA.
Gina
G
Suh
Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York, USA.
Julia K
JK
Goodrich
Department of Medicine, Stanford University School of Medicine, Stanford, California, USA.
Thomas D
TD
Haggerty
Department of Molecular Biology and Genetics, Cornell University, Ithaca, New York, USA; Department of Microbiology, Cornell University, Ithaca, New York, USA.
Ruth E
RE
Ley
Department of Medicine, Stanford University School of Medicine, Stanford, California, USA; Department of Health Research and Policy, Stanford University School of Medicine, Stanford, California, USA.
Julie
J
Parsonnet
microbicide; microbiome; randomized double-blind crossover study; triclosan