Triclosan and triclocarban exposure and thyroid function during pregnancy-A randomized intervention.
ABSTRACT: Triclosan and triclocarban (TCs) are broad-spectrum microbicides found in household and personal wash products. We sought to determine whether TC exposure from wash products or urinary triclosan level modified thyroid function during pregnancy or anthropometric measurements at birth. A randomized intervention of wash products with or without TCs, including toothpaste, enrolled pregnant women from 20 weeks' gestation. Urinary triclosan, TSH, T4 and T3 were assessed at enrollment, 36weeks' gestation and/or post-delivery; anthropometric measures at birth were ascertained from medical records. 78 and 76 mothers were assigned to the TC-containing and no-TC-containing product arms, respectively. No differences were observed in any thyroid function measure at any time point or in any anthropometric measurement at birth between either exposure arms or lowest and highest urinary triclosan quartile groups. TCs from wash products, primarily liquid and bar soaps, did not affect thyroid function measures during pregnancy or babies' anthropometric measures at delivery.
Project description:BACKGROUND:Triclosan and triclocarban (TCs) are broad-spectrum antimicrobials that, until recently, were found in a wide variety of household and personal wash products. Popular with consumers, TCs have not been shown to protect against infectious diseases. OBJECTIVES:To determine whether use of TC-containing wash products reduces incidence of infection in children less than one year of age. METHODS:Starting in 2011, we nested a randomized intervention of wash products with and without TCs within a multiethnic birth cohort. Maternal reports of infectious disease symptoms and antibiotic use were collected weekly by automated survey; household visits occurred every four months. Antibiotic prescriptions were identified by medical chart review. Urinary triclosan levels were measured in a participant subset. Differences by intervention group in reported infectious disease (primary outcome) and antibiotic use (secondary outcome) were assessed using mixed effects logistic regression and Fisher's Exact tests, respectively. RESULTS:Infectious illness occurred in 6% of weeks, with upper respiratory illness the predominant syndrome. Among 60 (45%) TC-exposed and 73 (55%) non-TC-exposed babies, infectious disease reports did not differ in frequency between groups (likelihood ratio test: p = 0.88). Medical visits with antibiotic prescriptions were less common in the TC group than in the non-TC group (7.8% vs. 16.6%, respectively; p = 0.02). CONCLUSIONS:Although randomization to TC-containing wash products was not associated with decreased infectious disease reports by mothers, TCs were associated with decreased antibiotic prescriptions, suggesting a benefit against bacterial infection. The recent removal of TCs from consumer wash products makes further elucidation of benefits and risks impracticable.
Project description:In 2016, the US Food and Drug Administration banned the use of specific microbicides in some household and personal wash products due to concerns that these chemicals might induce antibiotic resistance or disrupt human microbial communities. Triclosan and triclocarban (referred to as TCs) are the most common antimicrobials in household and personal care products, but the extent to which TC exposure perturbs microbial communities in humans, particularly during infant development, was unknown. We conducted a randomized intervention of TC-containing household and personal care products during the first year following birth to characterize whether TC exposure from wash products perturbs microbial communities in mothers and their infants. Longitudinal survey of the gut microbiota using 16S ribosomal RNA amplicon sequencing showed that TC exposure from wash products did not induce global reconstruction or loss of microbial diversity of either infant or maternal gut microbiotas. Broadly antibiotic-resistant species from the phylum Proteobacteria, however, were enriched in stool samples from mothers in TC households after the introduction of triclosan-containing toothpaste. When compared by urinary triclosan level, agnostic to treatment arm, infants with higher triclosan levels also showed an enrichment of Proteobacteria species. Despite the minimal effects of TC exposure from wash products on the gut microbial community of infants and adults, detected taxonomic differences highlight the need for consumer safety testing of antimicrobial self-care products on the human microbiome and on antibiotic resistance.
Project description:Triclosan (TCS) is one of the most common endocrine-disrupting chemicals (EDCs) present in household and personal wash products. Recently, concerns have been raised about the association between abnormal behavior in children and exposure to EDC during gestation. We hypothesized that exposure to TCS during gestation could affect brain development. Cortical neurons of mice were exposed in vitro to TCS. In addition, we examined in vivo whether maternal TCS administration can affect neurobehavioral development in the offspring generation. We determined that TCS can impair dendrite and axon growth by reducing average length and numbers of axons and dendrites. Additionally, TCS inhibited the proliferation of and promoted apoptosis in neuronal progenitor cells. Detailed behavioral analyses showed impaired acquisition of spatial learning and reference memory in offspring derived from dams exposed to TCS. The TCS-treated groups also showed cognition dysfunction and impairments in sociability and social novelty preference. Furthermore, TCS-treated groups exhibited increased anxiety-like behavior, but there was no significant change in depression-like behaviors. In addition, TCS-treated groups exhibited deficits in nesting behavior. Taken together, our results indicate that perinatal exposure to TCS induces neurodevelopment disorder, resulting in abnormal social behaviors, cognitive impairment, and deficits in spatial learning and memory in offspring.
Project description:BACKGROUND:Exposure to triclosan, an endocrine disrupting chemical, may affect thyroid hormone homeostasis and adversely affect neurodevelopment. OBJECTIVE:Using a longitudinal pregnancy and birth cohort, we investigated associations between triclosan exposures during different time windows, and cognitive test scores at 8 y of age in 198 children from the HOME Study. METHODS:We quantified triclosan in urine samples from mother-child pairs up to nine times between the second trimester of gestation and 8 y of age. The Wechsler Intelligence Scale for Children-IV [i.e., Full-Scale Intelligence Quotient (IQ)] assessment was administered to HOME Study children at 8 y of age. We estimated covariate-adjusted triclosan-IQ associations at each visit. We also tested whether associations between triclosan concentrations and cognitive test scores varied among exposure at different time periods. RESULTS:Full-Scale IQ was not significantly associated with urinary triclosan concentrations during gestation or childhood but was significantly associated with a 10-fold increase in maternal urinary triclosan concentration at delivery [-4.5?points (95% CI: -7.0, -2.0)]. Perceptual Reasoning Index (PRI) scores were significantly decreased in association with urinary triclosan concentrations at delivery and at 2 y of age. Associations between repeated triclosan concentrations and cognitive test scores significantly varied among exposure at different time periods for Full-Scale IQ, PRI, Verbal Comprehension Index, and Working Memory (triclosan-visit interaction p?0.04). CONCLUSION:Urinary triclosan concentrations at delivery, but not during mid to late pregnancy and childhood, were associated with significantly lower children's cognitive test scores at 8 y of age in this cohort of U.S. children. https://doi.org/10.1289/EHP2777.
Project description:Exposure to common environmental chemicals, including those found in personal care products has been linked to mammary cancer at high doses in animal models. Their effects at low doses at levels comparable to human exposure, especially during critical windows of development remain poorly understood. Using a Sprague-Dawley rat model, we investigated the effects of of three environmental chemicals – diethyl phthalate (DEP), methyl paraben (MPB) and triclosan (TCS) – on the transcriptome of normal developing mammary glands at low doses mimicking human exposure. Rats were exposed during three windows of early development – perinatal (gestation day (GD) 1 - 20 or postnatal day (PND) 1 - 20), prepubertal (PND 21 - 41) and pubertal (PND 42 - 62), as well as chronic exposure from birth to end of lactation (PND 1 - 146). Mammary gland whole-transcriptomes were profiled by Affymetrix rat gene 2.0 st arrays. Overall design: Female Sprague-Dawley rats were treated by oral gavage with low doses of diethyl phthalate (DEP), methyl paraben (MPB) or triclosan (TCS). These low doses were previously determined to produce urinary biomarker concentrations comparable to those reported for the US population (Teitelbaum SL et al, 2016). Control animals received the vehicle, olive oil (OIL). Exposure consisted of three short term windows – perinatal (gestation day (GD) 1 - 20 or postnatal day (PND) 1 - 20), prepubertal (PND 21 - 41) and pubertal (PND 42 - 62), as well as chronic exposure from birth to end of lactation (PND 1 - 146). There were 3-5 animals in each experimental group.
Project description:BACKGROUND:Triclosan is an antimicrobial chemical used in consumer products, and exposure is ubiquitous among pregnant women in the United States. Triclosan may reduce the levels of thyroid hormones that are important for fetal growth and development. OBJECTIVE:We investigated the relationship of prenatal triclosan exposure with birth anthropometry and gestational duration. METHODS:We used data from 378 mother-child pairs participating in the Health Outcomes and Measures of the Environment (HOME) Study, a prospective pregnancy and birth cohort from Cincinnati, OH. We measured triclosan concentrations in maternal urine samples collected at 16 and 26 weeks of pregnancy. We abstracted information on neonatal anthropometry and gestational duration from medical records. We used multivariable linear regression to estimate the covariate-adjusted association between the average of the two urinary triclosan concentrations and gestational age standardized weight z-score, length, head circumference, and gestational age at birth. RESULTS:Median urinary triclosan concentrations were 16ng/mL (range: <2.4 to 1501ng/mL). Each 10-fold increase in triclosan was associated with a predicted 0.15 standard deviation decrease (95% CI: -0.30, 0.00) in birth weight z-score, 0.4-cm decrease (95% CI: -0.8, 0.1) in birth length, 0.3-cm decrease (95% CI: -0.5, 0.0) in head circumference, and 0.3-week decrease (95% CI: -0.6, -0.1) in gestational age. Child sex did not modify the associations between triclosan and birth outcomes. CONCLUSIONS:In this cohort, maternal urinary triclosan concentrations during pregnancy were inversely associated with infants' birth weight, length, head circumference, and gestational age.
Project description:Exposure to common environmental chemicals, including those found in personal care products has been linked to mammary cancer at high doses in animal models. Their effects at low doses at levels comparable to human exposure remain poorly understood. Using a Sprague-Dawley rat model, we investigated the effects of three prevalently used environmental chemicals – diethyl phthalate (DEP), methyl paraben (MPB), triclosan (TCS) – and their mixture (MIX) on the transcriptome of normal developing mammary at levels mimicking human exposure. Rats were exposed from birth to adulthood in parous and nulliparous settings. We used affymetrix arrays to assess the influence of diethyl phthalate (DEP), methyl paraben (MPB), triclosan (TCS) and their mixture (MIX) on global gene expression profiles in rat mammary tissues, using doses comparable to human exposure. Exposure was from birth to adulthood (postnatal day 1 – 180) in parous and nulliparous rats. Overall design: Female Sprague-Dawley rats were treated by oral gavage with low doses of diethyl phthalate (DEP), methyl paraben (MPB), triclosan (TCS) or a mixture (MIX) of the three chemicals. These low doses were previously determined to produce urinary biomarker concentrations comparable to those reported for the US population (Teitelbaum SL, 2016). Control animals received the vehicle, olive oil (OIL). Exposure was from birth to adulthood (postnatal day 1 – 180) in parous and nulliparous rats. There were 5 animals in each experimental group.
Project description:BACKGROUND:Triclosan, an antimicrobial agent used in some consumer products, reduces endogenous thyroid hormone concentrations in rodents. Despite ubiquitous triclosan exposure and the importance of thyroid hormones for normal fetal development, few human studies have examined the impact of triclosan exposure on maternal, neonatal, or child thyroid hormones. METHODS:In the HOME Study, a prospective cohort from Cincinnati, OH, we measured urinary triclosan concentrations up to three times in pregnant women between 16weeks and delivery, and up to three times in children between age 1-3years. We quantified serum concentrations of thyroid stimulating hormone and total and free thyroxine and triiodothyronine in mothers at 16-weeks gestation (n=202), neonates at delivery (n=274), and children at age 3years (n=153). We estimated covariate-adjusted differences in thyroid hormones with a 10-fold increase in triclosan using linear regression and multiple informants models. RESULTS:Triclosan was not associated with thyroid hormones during pregnancy. We observed a few associations of triclosan concentrations with thyroid hormone concentrations in neonates at delivery and children at age 3years. Higher gestational triclosan, particularly around the time of delivery, was associated with lower cord serum total thyroxine (?: 0.3?g/dL; 95% CI: -0.6, -0.0). Childhood triclosan, particularly at age 1year, was positively associated with total thyroxine at age 3years (?: 0.7?g/dL; 95% CI: 0.3, 1.2). CONCLUSION:Our findings suggest that triclosan exposure may influence some features of neonatal and early child thyroid function. Given the large number of comparisons we made, these findings should be replicated in other cohorts.
Project description:Triclosan (TCS), an antibacterial agent, is identified in serum and urine of humans. Here, we show that the level of urinary TCS in 28.3% patients who had spontaneous abortion in mid-gestation were increased by 11.3-fold (high-TCS) compared with normal pregnancies. Oral administration of TCS (10?mg/kg/day) in mice (TCS mice) caused an equivalent urinary TCS level as those in the high-TCS abortion patients. The TCS-exposure from gestation day (GD) 5.5 caused dose-dependently fetal death during GD12.5-16.5 with decline of live fetal weight. GD15.5 TCS mice appeared placental thrombus and tissue necrosis with enhancement of platelet aggregation. The levels of placenta and plasma estrogen sulfotransferase (EST) mRNA and protein in TCS mice or high-TCS abortion patients were not altered, but their EST activities were significantly reduced compared to controls. Although the levels of serum estrogen (E2) in TCS mice and high-TCS abortion patients had no difference from controls, their ratio of sulfo-conjugated E2 and unconjugated E2 was reduced. The estrogen receptor antagonist ICI-182,780 prevented the enhanced platelet aggregation and placental thrombosis and attenuated the fetal death in TCS mice. The findings indicate that TCS-exposure might cause spontaneous abortion probably through inhibition of EST activity to produce placental thrombosis.
Project description:BACKGROUND:Exposure to triclosan, an antimicrobial chemical, is ubiquitous among pregnant women and may reduce thyroid hormone levels that are important for fetal neurodevelopment. Few studies have examined the association between prenatal triclosan exposure and children's neurobehavior. OBJECTIVE:We investigated the relationship of prenatal urinary triclosan concentrations with children's behavior and cognitive abilities at age three years in a prospective pregnancy and birth cohort in Canada. METHODS:We measured triclosan in urine samples collected at ~12?weeks of gestation in 794 Canadian women enrolled in a prospective pregnancy and birth cohort study (MIREC) from 2008 to 2011. Around age 3?years, we assessed children's cognitive abilities using the Wechsler Primary and Preschool Scale of Intelligence-III (WPPSI-III), and two scales of the Behavior Rating Inventory of Executive Function-Preschool (BRIEF-P). Parents reported children's problem and reciprocal social behaviors using the Behavior Assessment System for Children-2 (BASC-2) and Social Responsiveness Scale-2 (SRS-2), respectively. RESULTS:After adjusting for confounders using multivariable linear regression, triclosan was not associated with most of the 30 examined neurobehavioral scales. Each 10-fold increase in triclosan was associated with better WPPSI-III picture completion scores (?: 0.2; 95% CI: 0,0.5) and BASC-2 externalizing (?: -0.5; 95% CI: -1.1, 0) and hyperactivity (?: -0.6; 95% CI: -1.2, -0.1) scores, suggesting less externalizing and hyperactive behaviors. Child sex did not modify these associations. CONCLUSIONS:In this cohort, urinary triclosan concentrations measured once in early pregnancy were not associated with most assessed aspects of neurobehavior and weakly associated with a few others, but not in the hypothesized direction.