Urinary triclosan levels were found to be negatively associated with bone mineral density (BMD) and positively associated with osteoporosis in women, according to study results published in The Journal of Endocrinology & Metabolism.
Multiple factors may contribute to decreased BMD and osteoporosis. Triclosan, one of the known endocrine-disrupting chemicals, is an antimicrobial used in many personal care products, such as soap, hand sanitizer, toothpaste, and mouthwash. There are limited data regarding the association between triclosan exposure and human bone health.
The researchers analyzed the data obtained from 3 National Health and Nutrition Examination Surveys conducted between 2005 and 2010 in which urinary triclosan concentration and lumbar spine and proximal femur BMD were available. The goal of the study was to explore the association between urinary triclosan concentration and BMD levels in women.
The study enrolled 8829 women aged ≥20 years. Following exclusion due to missing data, 1848 women with complete data were included in the study. For each participant, a single spot urine specimen was collected and analyzed.
The weighted percentage of osteoporosis was 3.93% in total femur (91 participants), 4.82% in femoral neck (111 participants), 2.17% in trochanter (60 participants), 4.09% in the intertrochanter region (91 participants), and 6.36% overall (143 participants).
After adjustment for covariates, there were significant associations between tertile 3 of triclosan concentration and lower BMD in regions of total femur (β=-0.016; 95% CI, -0.032 to 0.000), intertrochanter (β=-0.022; 95% CI, -0.042 to -0.002), and lumbar spine (β=-0.014; 95% CI, -0.029 to 0.001), relative to tertile 1. This association was stronger in postmenopausal women and was not present in premenopausal women.
As for the association between urinary triclosan and osteoporosis, compared with women at tertile 1, women at tertile 3 were almost 2.5-fold more likely to have increased prevalence of osteoporosis in the intertrochanter region (odds ratio, 2.464; 95% CI, 1.190-5.105). However, there were no significant associations between different levels of urinary triclosan with osteoporosis in the other 3 regions or overall.
Other than the cross-sectional design, which is not able to indicate cause and effect associations, there were additional study limitations, including measurement of triclosan in spot urine sample, which may not represent intra-individual variability and long-term exposure. In addition, there was a lack of long-term repeated BMD measurements, which is important to assess bone health status.
“Higher [triclosan] exposure was associated with lower BMD in total femur, intertrochanter and lumbar spine, and higher prevalence of osteoporosis in intertrochanter. The association was more pronounced in postmenopausal women,” concluded the researchers.
Cai S, Zhu J, Sun L, et al. Association between urinary triclosan with bone mass density and osteoporosis in the US adult women, 2005-2010 [published online June 25, 2019]. J Clin Endocrinol Metab. doi:10.1210/jc.2019-00576