Biomonitoring of exposure to bisphenols, benzophenones, triclosan, and triclocarban in pet dogs and cats

An evaluation of dogs' exposure to benzophenones through hair sample analysis

Introduction

Benzophenones (BPs) are used in various branches of industry as ultraviolet radiation filters, but they pollute the natural environment, penetrate living organisms, and disrupt endocrine balance. Knowledge of the exposure of domestic animals to these substances is extremely scant. The aim of the study was to investigate long-term exposure of companion dogs to BPs and relate this to environmental factors.

Material and Methods

Hair samples taken from 50 dogs and 50 bitches from under 2 to over 10 years old were analysed for BP content with liquid chromatography-tandem mass spectrometry.

Results

The results revealed that dogs are most often exposed to 2-hydroxy-4-methoxybenzophenone (BP-3) and 4-dihydroxybenzophenone (BP-1). Concentration levels of BP-3 above the method quantification limit (MQL) were noted in 100% of the samples and fluctuated from 4.75 ng/g to 1,765 ng/g. In turn, concentration levels of BP-1 above the MQL were noted in 37% of the samples and ranged from <0.50 ng/g to 666 ng/g. Various factors (such as the use of hygiene and care products and the dog's diet) were found to affect BP concentration levels. Higher levels of BP-3 were observed in castrated/spayed animals and in animals that required veterinary intervention more often.

Conclusion

The results obtained show that the analysis of hair samples may be a useful matrix for biomonitoring BPs in dogs, and that these substances may be toxic to them.

Feasibility of sulfated BPA and BPS as wastewater-based epidemiology biomarkers: Insights from wastewater and reported human urine analysis

In wastewater-based epidemiology (WBE), the selection of appropriate biomarkers presents a significant challenge. Recently, sulfated bisphenols have garnered attention as potential WBE biomarkers due to their increased stability in wastewater compared to glucuronide conjugates. This study aims to comprehensively assess the feasibility of employing sulfated BPA and BPS as WBE biomarkers by analyzing both WBE and human biomonitoring data. To conduct this research, wastewater samples were collected from six domestic wastewater treatment plants in Guangzhou, China, and urinary concentration of BPA and BPS were obtained from peer-reviewed literature. The results revealed that mean urinary concentrations of BPA and BPS, calculated using Monte Carlo simulations, significantly exceeded those reported in human biomonitoring studies. Furthermore, the per capita mass load ratio of sulfated BPA and BPS in human urine to the mass load in wastewater was found to be below 10 %. This outcome suggests that the excretion of BPA-S and BPS-S in urine does not make a substantial contribution to wastewater, hinting at the existence of other notable sources. Consequently, our study concludes that sulfated BPA-S and BPS-S are not suitable candidates as WBE biomarkers. This work provides a referenceable analytical framework for evaluating the feasibility of WBE biomarkers and emphasizes the necessity for caution when utilizing WBE to assess human exposure to chemicals.

Biomonitoring of benzophenones in guano samples of wild bats in Poland

Benzophenones (BPs) are substances used in the production of sunscreens, cosmetics, and personal care products. However, there is a lack of knowledge of BPs in wild animals. Therefore, the study aimed to assess the concentration of selected BPs commonly used in the cosmetic industry in guano samples collected from 4 colonies of greater mouse-eared bats (Myotis myotis). Liquid chromatography with tandem mass spectrometry (LC-MS/MS) was used to determine guano concentrations of benzophenone 1 (BP-1), benzophenone 2 (BP-2), benzophenone 3 (BP-3) and benzophenone 8 (BP-8). BP-1 levels above the method quantification limit (MQL) were noted in 97.5% of samples and fluctuated from <0.1 ng/g to 259 ng/g (mean 41.50 ng/g, median 34.8). The second most common was BP-3, which fluctuated from <0.1 ng/g to 19 ng/g (mean 6.67 ng/g, median 5.05), and its levels higher than MQL were observed in 40% of samples. BP-2 and BP-8 concentrations did not exceed the method detection limit (0.04 ng/g) in any analyzed sample. There were visible differences in the BP-1 and BP-3 levels among the studied bat colonies. Mean BP-1 concentration fluctuated from 11.23±13.13 ng/g to 76.71±65.51 ng/g and differed significantly between the colonies. Mean BP-3 concentration fluctuated from 5.03±6.03 ng/g to 9.18±7.65 mg/g, but it did not differ significantly between the colonies. The results show that guano is a suitable matrix for the assessment of wildlife exposure to BPs. This could be particularly advantageous in protected species, where not disturbing and stressing the animals are crucial.

Dilute-and-shoot coupled to mixed mode liquid chromatography-tandem mass spectrometry for the analysis of persistent and mobile organic compounds in human urine

In this work, a comprehensive method for the simultaneous determination of 33 diverse persistent and mobile organic compounds (PMOCs) in human urine was developed by dilute-and-shoot (DS) followed by mixed-mode liquid chromatography coupled with tandem mass spectrometry (MMLC-MS/MS). In the sample preparation step, DS was chosen since it allowed the quantification of all targets in comparison to lyophilization. For the chromatographic separation, Acclaim Trinity P1 and P2 trimodal columns provided greater capacity for retaining PMOCs than reverse phase and hydrophilic interaction liquid chromatography. Therefore, DS was validated at 5 and 50 ng/mL in urine with both mixed mode columns at pH = 3 and 7. Regarding figures of merit, linear calibration curves (r2 > 0.999) built between instrumental quantification limits (mostly below 5 ng/mL) and 500 ng/mL were achieved. Despite only 60% of the targets were recovered at 5 ng/mL because of the dilution, all PMOCs were quantified at 50 ng/mL. Using surrogate correction, apparent recoveries in the 70-130% range were obtained for 91% of the targets. To analyse human urine samples, the Acclaim Trinity P1 column at pH = 3 and 7 was selected as a consensus between analytical coverage (i.e. 94% of the targets) and chromatographic runs. In a pooled urine sample, industrial chemicals (acrylamide and bisphenol S), biocides and their metabolites (2-methyl-4-isothiazolin-3-one, dimethyl phosphate, 6-chloropyridine-3-carboxylic acid, and ammonium glufosinate) and an artificial sweetener (aspartame) were determined at ng/mL levels. The outcomes of this work showed that humans are also exposed to PMOCs due to their persistence and mobility, and therefore, further human risk assessment is needed.

Co-exposure to parabens and triclosan and associations with cognitive impairment in an elderly population from Shenzhen, China

Parabens and triclosan (TCS) have been extensively applied in personal care products (PCPs) as preservatives and antibacterial agents. However, their potentiality to disrupt the neurological system has induced increasing concern. The elderly population is at a higher risk of neurodegenerative disorder, although research on its association with PCP exposure remains scarce. Here, we measured the urinary levels of four parabens, TCS, and an oxidative stress marker among 540 participants from the Shenzhen aging-related disorder cohort during 2017-2018. The Mini-Mental State Examination (MMSE) was used to assess the cognitive status of participants. Their demographic, dietary, and behavioral factors were collected via questionnaire survey. Among the four paraben analogs, the median concentration of methyl parabens (MeP) was the highest (Low-risk group: 1.21 ng/mL, High-risk group: 1.64 ng/mL). TCS and 8-hydroxy-2'-deoxyguanosine (8-OHdG) were detected in more than 90% of the samples. Weighted quantile sum regression and quantile-based g-computation showed that the combined effect of all analytes was positively associated with the level of 8-OHdG. BtP, EtP and MeP were identified as the major contributors to the joint effect. After stratification by gender, females exhibited more pronounced changes in urinary 8-OHdG level than males. However, the positive correlation between co-exposure to parabens and TCS and cognitive impairment was not significant (p > 0.05) in both models, which warrants investigation with the larger sample size.

Domestic dogs as sentinels of children lead exposure: Multi-pathway identification and source apportionment based on isotope technique

Environmental lead exposure poses risks to children' health, thus exposure sources and pathways identification remain important concern and research scope. Due to sharing the same environment, domestic animals, especially dogs, have been used as useful sentinels to identify human lead exposure. However, more evidence is needed on whether domestic dogs could be used to identify the lead exposure pathways and sources of children. Thus, this study investigated the dietary habits, behaviors, and household environment of children and dogs in a typical coal-fired area in China. The lead levels and lead isotope ratios (Acronym: LIRs, expressed as ²⁰⁸Pb/²⁰⁶Pb and ²⁰⁷Pb/²⁰⁶Pb) in dogs' and children's blood, as well as in environmental media (food, PM_2.5, indoor/outdoor dust, drinking water and soil) were measured to explore the predominant lead pollution sources and exposure pathways of children. The results showed that the LIRs of children's blood (²⁰⁸Pb/²⁰⁶Pb = 2.0703 ± 0.0076, ²⁰⁷Pb/²⁰⁶Pb = 0.8501 ± 0.0052) were similar to those of dogs' blood (²⁰⁸Pb/²⁰⁶Pb = 2.0696 ± 0.0085, ²⁰⁷Pb/²⁰⁶Pb = 0.8499 ± 0.0052), as well as similar to the LIRs of environmental media, i.e. children's food (²⁰⁸Pb/²⁰⁶Pb = 2.0731 ± 0.0057, ²⁰⁷Pb/²⁰⁶Pb = 0.8491 ± 0.0036) and coal (²⁰⁸Pb/²⁰⁶Pb = 2.0683 ± 0.017, ²⁰⁷Pb/²⁰⁶Pb = 0.8515 ± 0.01). Children and dogs had similar lead exposure pathways, but the contributions of each exposure pathway were different, i.e., 83.1% vs. 76.9% for children and dogs via food ingestion, 1.4% vs. 5.6% via particulate matter exposure, and 15.5% vs. 17.5% via household dust exposure, respectively. The contribution of food via ingestion to lead exposure remains dominant, and coal combustion is a main lead exposure source for children and domestic dogs.

Evaluation of Parabens and Bisphenol A Concentration Levels in Wild Bat Guano Samples

Parabens and bisphenol A are synthetic compounds found in many everyday objects, including bottles, food containers, personal care products, cosmetics and medicines. These substances may penetrate the environment and living organisms, on which they have a negative impact. Till now, numerous studies have described parabens and BPA in humans, but knowledge about terrestrial wild mammals' exposure to these compounds is very limited. Therefore, during this study, the most common concentration levels of BPA and parabens were selected (such as methyl paraben-MeP, ethyl paraben-EtP, propyl paraben-PrP and butyl paraben-BuP) and analyzed in guano samples collected in summer (nursery) colonies of greater mouse-eared bats (Myotis myotis) using liquid chromatography with the tandem mass spectrometry (LC-MS-MS) method. MeP has been found in all guano samples and its median concentration levels amounted to 39.6 ng/g. Other parabens were present in smaller number of samples (from 5% for BuP to 62.5% for EtP) and in lower concentrations. Median concentration levels of these substances achieved 0.95 ng/g, 1.45 ng/g and 15.56 ng/g for EtP, PrP and BuP, respectively. BPA concentration levels did not exceed the method quantification limit (5 ng/g dw) in any sample. The present study has shown that wild bats are exposed to parabens and BPA, and guano samples are a suitable matrix for studies on wild animal exposure to these substances.

Temporal trends in risk of bisphenol A, benzophenone-3 and triclosan exposure among U.S. children and adolescents aged 6-19 years: Findings from the National Health and Nutrition Examination Survey 2005-2016

BACKGROUND

Phenolic compounds with potential adverse health effects are gradually being replaced. Little is known about the potential health risks of BPA, BP3, and TCS exposure in children and adolescents aged 6-19 years in the United States.

OBJECTIVES

To determine trends and rates of change in hazard indices (HI) for three phenolics in U.S. children and adolescents for BPA, BP3, TCS, and to assess changes in gender, race/ethnicity, age, and potential health risks.

METHODS

Metabolic biomonitoring data from field-collected urine samples from the National Health and Nutrition Examination Survey (NHANES) were utilized. Daily intake of three phenols (bisphenol A, benzophenone-3, and triclosan) between 2005 and 2016 in children and adolescents were obtained. Cumulative risk indicators, including hazard quotient (HQ), hazard index (HI), and maximum cumulative ratio (MCR), were used for the health risk assessment of the three phenols.

RESULTS

During this period, the change in LSGM HI was -2.9% per cycle [95% Cl: (-3.7%, -2.2%)], and the percentage of participants with HI > 0.1 decreased from 15.6% to 10.5%. Children (6-11 years) had higher mean HI values than adolescents (12-19 years), while female had higher LSGM HI values than male. MCR values were generally low and negatively correlated with HI. However, the average value of MCR increased from 1.722 to 2.107 during this period.

CONCLUSION

Exposure to phenolics among U.S. children and adolescents has changed in recent decades. However, gaps in data limit the interpretation of trends but legislative activity and advocacy campaigns by nongovernmental organizations may play a role in changing trends. Moreover, there are growing concerns about the potential health risks associated with exposure to multiple phenols in children and adolescents.

Assessment of exposure to volatile organic compounds through urinary concentrations of their metabolites in pet dogs and cats from the United States

Volatile organic compounds (VOCs) are ubiquitous environmental pollutants, exposure to which is associated with birth defects, neurocognitive and reproductive impairments, and cancer. Little is known, however, about VOC exposure in pet dogs and cats, which represent sentinels for human exposure as well as having value as companion animals. In this study, we determined 38 VOC metabolites (VOCMs) in urine samples collected from 47 dogs and 42 cats from the Albany area of New York State. Seventeen (in cats) to twenty (in dogs) VOCMs were found at detection frequencies (DFs) above 60%. The creatinine-adjusted geometric mean (GM) concentrations of individual VOCMs ranged from 5.43 (EMA) to 761 μg/g (3HPMA) in dog urine and 0.824 (SBMA) to 278 μg/g (ATCA) in cat urine. The ∑20 VOCM concentration in dog urine was 2280 μg/g (geometric mean) and the ∑17 VOCM concentration in cat urine was 847 μg/g. Eight individual VOCMs were significantly more abundant in dog than in cat urine, and the urinary concentrations of several VOCMs in dogs were comparable to those reported for human tobacco smokers. Metabolites of acrolein accounted for 43% of ∑20 VOCM concentration in dogs, whereas those of cyanide and benzene accounted for 60% of ∑17 VOCM concentration in cats. Based on acrylamide exposure doses, calculated hazard quotients were above 1 in 77% of dogs and 50% of cats studied, and cancer risk values (using a benchmark of 10^-6) from exposure to acrylamide exceeded 1 for all dogs and cats. This is the first study to report VOCM concentrations in urine collected from pet dogs and cats and highlights the need to identify sources and health implications of VOCs exposure in these animals.

Early life exposure to triclosan from antimicrobial daily necessities may increase the potential risk of autism spectrum disorder: A multicenter study in China

BACKGROUND

Autism spectrum disorders (ASD) are a group of complex neurodevelopmental disorders with unclear etiologies. Our recent work indicated that maternal exposure to triclosan (TCS) significantly increased the autistic-like behavior in rats, possibly through disrupting neuronal retinoic acid signaling. Although environmental endocrine disruptors (EEDs) have been associated with autism in humans, the relationship between TCS, one of the EEDs found in antibacterial daily necessities, and autism has received little attention.

OBJECTIVE

The aims of this multicenter study were to evaluate TCS concentrations in typically developing (TD) children and ASD children, and to determine the relationship between TCS levels and the core symptoms of ASD children.

METHODS

A total of 1345 children with ASD and 1183 TD children were enrolled from 13 cities in China. Ages ranged between 2 and 7 years. A questionnaire was used to investigate the maternal use of antibacterial daily necessities (UADN) during pregnancy. The core symptoms of ASD were evaluated using the Autism Behavior Checklist (ABC), Childhood Autism Rating Scale (CARS), Social Response Scale (SRS), and the Children Neuropsychological and Behavior Scale-Revision 2016 (CNBS-R2016). The TCS concentration was measured using LC-MS/MS.

RESULTS

Maternal UADN during pregnancy may be an unrecognized potential environmental risk factor for ASD (OR=1.267, P = 0.023). Maternal UADN during pregnancy strongly correlated with TCS levels in the offspring (Adjusted β = 0.277, P < 0.001). TCS concentration was higher in ASD children (P = 0.005), and positively correlated with ABC (Sensory subscales: P = 0.03; Social self-help subscales: P = 0.011) and SRS scale scores (Social awareness subscales: P = 0.045; Social communication subscales: P = 0.001; Autism behavior mannerisms subscales: P = 0.006; SRS total score: P = 0.003) in ASD children. This association was more pronounced in boys than in girls.

CONCLUSION

To our knowledge, this is the first case-control study to examine the correlation between TCS and ASD. Our results suggest that maternal UADN during pregnancy may be a potential risk of ASD in offspring. Further detection of TCS levels showed that maternal UADN during pregnancy may be associated with excessive TCS exposure. In addition, the level of TCS in children with ASD is higher than TD children. The higher levels of TCS in children with ASD may be significantly associated with more pronounced core symptoms, and this association was more significant in male children with ASD.

Integrated Exposomics/Metabolomics for Rapid Exposure and Effect Analyses

The totality of environmental exposures and lifestyle factors, commonly referred to as the exposome, is poorly understood. Measuring the myriad of chemicals that humans are exposed to is immensely challenging, and identifying disrupted metabolic pathways is even more complex. Here, we present a novel technological approach for the comprehensive, rapid, and integrated analysis of the endogenous human metabolome and the chemical exposome. By combining reverse-phase and hydrophilic interaction liquid chromatography (HILIC) and fast polarity-switching, molecules with highly diverse chemical structures can be analyzed in 15 min with a single analytical run as both column's effluents are combined before analysis. Standard reference materials and authentic standards were evaluated to critically benchmark performance. Highly sensitive median limits of detection (LODs) with 0.04 μM for >140 quantitatively assessed endogenous metabolites and 0.08 ng/mL for the >100 model xenobiotics and human estrogens in solvent were obtained. In matrix, the median LOD values were higher with 0.7 ng/mL (urine) and 0.5 ng/mL (plasma) for exogenous chemicals. To prove the dual-column approach's applicability, real-life urine samples from sub-Saharan Africa (high-exposure scenario) and Europe (low-exposure scenario) were assessed in a targeted and nontargeted manner. Our liquid chromatography high-resolution mass spectrometry (LC-HRMS) approach demonstrates the feasibility of quantitatively and simultaneously assessing the endogenous metabolome and the chemical exposome for the high-throughput measurement of environmental drivers of diseases.

From target analysis to suspect and non-target screening of endocrine-disrupting compounds in human urine

In the present work, a target analysis method for simultaneously determining 24 diverse endocrine-disrupting compounds (EDCs) in urine (benzophenones, bisphenols, parabens, phthalates and antibacterials) was developed. The target analysis approach (including enzymatic hydrolysis, clean-up by solid-phase extraction and analysis by liquid chromatography coupled to tandem mass spectrometry (LC–MS/MS)) was optimized, validated and applied to volunteers’ samples, in which 67% of the target EDCs were quantified. For instance, benzophenone-3 (0.2–13 ng g⁻¹), bisphenol A (7.7–13.7 ng g⁻¹), methyl 3,5-dihydroxybenzoate (8–254 ng g⁻¹), mono butyl phthalate (2–17 ng g⁻¹) and triclosan (0.3–9 ng g⁻¹) were found at the highest concentrations, but the presence of other analogues was detected as well. The developed target method was further extended to suspect and non-target screening (SNTS) by means of LC coupled to high-resolution MS/MS. First, well-defined workflows for SNTS were validated by applying the previously developed method to an extended list of compounds (83), and then, to the same real urine samples. From a list of approximately 4000 suspects, 33 were annotated at levels from 1 to 3, with food additives/ingredients and personal care products being the most abundant ones. In the non-target approach, the search was limited to molecules containing S, Cl and/or Br atoms, annotating 4 pharmaceuticals. The results from this study showed that the combination of the lower limits of detection of MS/MS and the identification power of high-resolution MS/MS is still compulsory for a more accurate definition of human exposome in urine samples.

Urinary and fecal excretion of aromatic amines in pet dogs and cats from the United States

Several primary aromatic amines (AAs) are known or suspected carcinogens. Despite this, the exposure of pet animals to this class of chemicals is unknown. In this study, we investigated the occurrence of 30 AAs and two tobacco chemical markers (nicotine and cotinine) in 63 pet urine (42 dog and 21 cat) and 77 pet feces (37 dog and 40 cat) samples collected from the Albany area of New York State. Eight of the 30 AAs (∑₈AAs) were found in > 38% of dog and cat urine samples, at median concentrations of 7.99 (range: 0.42-52.3 ng/mL) and 31.4 (2.63-75.9) ng/mL, respectively. Nine of the 30 AAs (∑₉AAs) were found in > 73% of dog and cat feces samples, at median concentrations of 278 (range: 61.7-613 ng/g) and 240 (55.4-645) ng/g dry wt, respectively. Among the 30 AAs, 2,6-dimethylaniline (2,6-DMA) accounted for the highest median concentrations in both urine and fecal samples. Median concentrations of nicotine and cotinine were below 0.92 ng/mL in urine and below 3.86 ng/g in feces of both dogs and cats. No significant relationship was found between AA concentrations and pet age or gender. The lack of significant Spearman's rank correlation between the concentrations of AA and nicotine in pet urine/feces suggested that sources other than tobacco smoke contributed to AA exposure in pets. Furthermore, the calculated fecal excretion rates of AAs were higher than the intake rates (estimated through reverse dosimetry), which indicates that cats and dogs are exposed to AA precursors such as azo dyes. Concentrations in urine and feces reflected exposure to direct and indirect exposure sources, respectively, of AAs.

Hair Sample Analysis as a Method of Monitoring Exposure to Bisphenol A in Dogs

Bisphenol A (BPA) is an organic substance widely used in the plastics industry. It penetrates food and environment and, as an endocrine disruptor, has detrimental effects on human organisms. Pet animals, which live in the immediate vicinity of humans, are also exposed to BPA; however, knowledge regarding the exposure of dogs to this substance is extremely scarce. This is the first study in which hair analysis has been used to biomonitor BPA in 30 dogs using liquid chromatography and tandem mass spectrometry techniques. The presence of BPA in concentration levels above the method detection limit (1.25 ng/g) was noted in 93.33% of samples. BPA concentration levels were found to range from 7.05 ng/g to 436 ng/g (mean 81.30 ng/g). Statistically significant differences in BPA concentration levels were found between animals with physiological weight and animals with abnormal weight (skinny and obese). In turn, differences between males and females, as well as between young, middle-aged and old dogs, were not statistically significant. The obtained results have clearly shown that hair analysis is a useful method to evaluate the exposure of dogs to BPA. This study also confirmed that dogs are exposed to BPA to a large extent, and this substance may play a role as a pathological factor in this animal species. However, many aspects connected to the influence of BPA on canine health status are unclear and need further study.

The Presence of Triclosan in Human Hair Samples in Poland-A Pilot Study

Triclosan (TCS) is an organic substance showing antibacterial action, which is commonly used in many branches of industry, including, among others, cosmetics, pharmaceuticals and the food industry. TCS may penetrate into living organisms and negatively affect the health of humans and animals. The majority of previous investigations on TCS biomonitoring in humans have been performed on urine, but currently, studies on hair samples are becoming increasingly important. The aim of this study was to evaluate TCS concentration levels in residents of Olsztyn, a city in northeastern Poland, using a liquid chromatography-mass spectrometry technique. The presence of TCS was observed in 96.7% of samples tested, with concentration levels from 37.9 pg/mg to 3386.5 pg/mg. The mean concentration level of TCS in the present study was 402.6 (±803.6) pg/mg, and the median value was 103.3 pg/mg. Although there were some differences in TCS concentration levels between males and females, humans of various ages and humans with colored and natural hair had no statistically significant differences in TCS concentration levels. The obtained results have clearly indicated that people living in northeastern Poland are exposed to TCS to a large degree, and hair analysis, despite some limitations, is a suitable method for TCS biomonitoring in humans.

Several typical endocrine-disrupting chemicals in human urine from general population in China: Regional and demographic-related differences in exposure risk

Endocrine-disrupting chemicals (EDCs) are ubiquitous in the environment, and human exposure to these pollutants has caused great public concern. Five groups of EDCs, including parabens, antimicrobials (triclosan (TCS) and triclocarban (TCC)), bisphenols (BPs), tetrabromobisphenol A and its alternatives (TBBPAs), and benzophenones, in urines of general populations from three cities with different economic levels in China were determined simultaneously to evaluate the coexposure levels of such chemicals. The total concentration of target compounds was approximately two times higher in the urines from Chengdu (a first-tier city; geometric mean: 2.50 μg/L) than that from Nantong (a second-tier city; 1.34 μg/L), and was one order of magnitude higher than that from Shehong (a fifth-tier city; 0.73 μg/L). Urinary target compounds were significantly correlated with gender, age, body mass index (BMI), education level, occupation, and diet. The estimated daily intakes of target chemicals ranged from 0.002 (benzophenones) to 10.2 µg/kg-bw/day (parabens). The exposure estimate showed that females were more vulnerable to exposure to these EDCs. This study profiles the regional and demographic-related differences in the concentrations and exposure risks of several typical EDCs in urines from general populations in three cities with different economic levels in China.

Concentrations of bisphenols, benzophenone-type ultraviolet filters, triclosan, and triclocarban in the paired urine and blood samples from young adults: Partitioning between urine and blood

Bisphenols (BPs), benzophenone-type UV filters (BP-type UV filters), triclosan (TCS), and triclocarban (TCC) are endocrine-disrupting chemicals (EDCs) and commonly used in consumer and personal care products. In the present study, seven BPs, eight BP-type UV filters, TCS, and TCC were quantified in 196 paired urine and blood samples collected from young adults in South China. Benzophenone-7 and benzophenone-9 were not detected in all samples, while other target compounds were widely detected in 39%-96% of the urine and 14%-96% of the blood samples, and the median concentrations ranged from <0.02 (specific gravity adjusted: < 0.02) to 2.33 (2.05) ng/mL and <0.01-2.66 ng/mL in the urine and blood samples, respectively. Females had higher levels of most target analytes, and gender-related differences (p < 0.05) were found in the blood levels of benzophenone-2 (females vs. males: 0.84 vs. <0.01 ng/mL), ΣBP (sum of BP-type UV filters; 1.61 vs. 0.98 ng/mL), TCS (3.89 vs. 1.69 ng/mL), and ΣTC (sum of TCS and TCC; 5.77 vs. 3.02 ng/mL). We calculated the portioning of the target compounds between blood and urine (B/U ratios). The B/U ratios of bisphenol F, benzophenone-2, benzophenone-6, 4-hydroxy benzophenone, TCS, and TCC were higher than 1, showing that these analytes have higher enrichment capacities in human blood. To the best of our knowledge, this is the first study to simultaneously analyze the concentrations of BPs, BP-type UV filters, TCS, and TCC in the paired urine and blood samples of young adults in South China.

Assessment of exposure to perfluoroalkyl substances (PFASs) in dogs by fur analysis

Poly- and perfluoroalkyl substances (PFASs) are a large group of chemicals commonly used in various branches of industry, which may adversely affect the living organisms. The aim of this study were to evaluate exposure of dogs to six selected PFASs: five perfluoroalkyl carboxylic acids (perfluorobutanoic acid - PFBuA, perfluoropentanoic acid - PFPeA, perfluorohexanoic acid - PFHxA, perfluoroheptanoic acid - PFHpA, perfluorooctanoic acid - PFOA) and perfluorooctane sulfonic acid (PFOS) through the analysis of fur samples. To our knowledge this is the first study concerning the use of fur samples to evaluation of exposure of domestic animals to PFASs. Relationship between PFASs concentration and age, gender and body weight of animals was also evaluated. Fur samples were collected from 30 dogs living in Olsztyn (Poland). All PFASs studied were detected in the canine fur samples. The highest concentrations were observed in the case of PFOA and PFBuA, detected at concentrations in the range between 1.51 and 66.7 ng/g and 0.98-26.6 ng/g, respectively. During the present study generally no statistically significant differences dependent on gender, age and body weight of animals were found. This study confirms the suitability of fur samples for biomonitoring of exposure to PFASs in domestic animals, what may be important in veterinary toxicology.

Triclosan-induced glycolysis drives inflammatory activation in microglia via the Akt/mTOR/HIF 1α signaling pathway

Exposure to triclosan (TCS) has been implicated in neurotoxicity including autism spectrum disorders in vivo and oxidative stress and cell apoptosis in vitro. Thus, the molecular mechanisms underlying TCS-induced neurotoxicity warrants further research. In this study, we try to address the mode of action that TCS induced the expression of inflammatory cytokines by shifting metabolism to glycolysis. BV-2 cells were treated with 20 μM TCS for 24 h, and the conditional medium from TCS-induced activated microglia reduced the viability of the murine hippocampal neurons cell line HT22. Protein expression levels in the nuclear factor kappa B (NF-κB) signaling pathway were measured through Western blotting, and the expression levels of inflammatory cytokine were measured using quantitative real-time PCR. The results showed that exposure to TCS enhanced NF-κB activation, increased inflammatory cytokine expression including interleukin (IL) 1β, IL-6, and tumor necrosis factor (TNF) α in the BV-2 cells. The glucose consumption and lactate production in BV2 cell increased sharply after exposure to TCS for 24 h. Based on our qPCR and Western blotting results, the expression of the key glycolysis enzymes-namely hexokinase 1, pyruvate kinase M2, and lactate dehydrogenase A-increased after treatment with 20 μM TCS. Furthermore, inhibiting glycolysis by 2-deoxy-D-glucose reduced the activation of NF-κB and the mRNA expression of the inflammatory cytokines in the TCS-activated BV-2 microglia. The expression of the proteins of the Akt/mTOR/HIF1α pathway examined through Western blotting, which regulates glycolysis, also increased in the BV2 cells exposed to TCS. Moreover, Akt and mTOR inhibition by using LY294002 and rapamycin, respectively, blocked inflammatory cytokine overexpression induced by TCS. In conclusion, TCS can induce glycolysis and directly drive inflammatory activation in microglia; with the mediation of the Akt/mTOR/HIF1α pathway.

The Different Facets of Triclocarban: A Review

In the late 1930s and early 1940s, it was discovered that the substitution on aromatic rings of hydrogen atoms with chlorine yielded a novel chemistry of antimicrobials. However, within a few years, many of these compounds and formulations showed adverse effects, including human toxicity, ecotoxicity, and unwanted environmental persistence and bioaccumulation, quickly leading to regulatory bans and phase-outs. Among these, the triclocarban, a polychlorinated aromatic antimicrobial agent, was employed as a major ingredient of toys, clothing, food packaging materials, food industry floors, medical supplies, and especially of personal care products, such as soaps, toothpaste, and shampoo. Triclocarban has been widely used for over 50 years, but only recently some concerns were raised about its endocrine disruptive properties. In September 2016, the U.S. Food and Drug Administration banned its use in over-the-counter hand and body washes because of its toxicity. The withdrawal of triclocarban has prompted the efforts to search for new antimicrobial compounds and several analogues of triclocarban have also been studied. In this review, an examination of different facets of triclocarban and its analogues will be analyzed.

Co-exposure and health risks of parabens, bisphenols, triclosan, phthalate metabolites and hydroxyl polycyclic aromatic hydrocarbons based on simultaneous detection in urine samples from guangzhou, south China

Polycyclic aromatic hydrocarbons (PAHs) and certain ingredients in personal care products, such as parabens, bisphenols, triclosan and phthalate metabolites, have become ubiquitous in the world. Concerns of human exposure to these pollutants have increased during recent years because of various adverse health effects of these chemicals. Multiple compounds including parabens, bisphenols, triclosan, phthalate metabolites (mPAEs) and hydroxyl PAHs (OH-PAHs) in urine samples from Guangzhou were determined simultaneously to identify the human exposure pathways without external exposure data combined with data analysis, and the toxicants posed the highest risk to human health were screened in the present study. The detection frequencies for the chemicals exceeded 90%. Among the contaminants, mPAEs showed the highest concentrations, followed by OH-PAHs, with triclosan present at the lowest concentrations. Mono-n-butyl phthalate, methylparaben, bisphenol A, and hydroxynaphthalene represented the most abundant mPAE, parabens, bisphenol, and OH-PAH compounds, respectively. The present PAHs are mainly exposed to human through inhalation, while the chemicals added to personal care products are mainly exposed to human through oral intake and dermal contact. The urine samples from suburban subjects showed significantly higher OH-PAH levels than the urine samples from urban subjects, and females had lower OH-PAH levels than males. Urinary concentrations of the analyzed contaminants were significantly correlated with age, body mass index, residence time, as well as the frequencies of alcohol consumption and swimming. Risk assessments based on Monte Carlo simulation indicated that approximately 30% of the subjects suffered non-carcinogenic risks from mPAEs and OH-PAHs, with mPAEs accounting for 89% of the total risk.

Characterization of triclosan and triclocarban in indoor dust from home micro-environments in Vietnam and relevance of non-dietary exposure

Contamination status, spatial variability, and exposure risk of triclosan (TCS) and triclocarban (TCC) in indoor dusts from different micro-environments were evaluated for the first time in Vietnam as well as in Southeast Asian region. TCS and TCC were measured in 89 dust samples collected from bedrooms, living rooms, and kitchens of private houses in four northern cities including Hanoi, Bac Ninh, Hung Yen, and Nam Dinh, by means of liquid chromatography-tandem mass spectrometry. Concentrations of TCS and TCC ranged from <5 to 1090 (median 33.2) and from <3 to 531 (median 19.3) ng g^-1, respectively. Concentrations of TCS and TCC in the kitchen and bedroom dusts were markedly higher than levels found in the living room samples, probably due to their applications in kitchen utensils, household cleaning reagents, and personal care products. A strong positive correlation between TCS and TCC concentrations was detected in the whole dataset (R² = 0.810, p < 0.001). For samples in which both TCS and TCC were quantified, TCS/TCC ratios ranged from 0.3 to 12 with a median value of 1.8, and did not show big differences between micro-environments. Human exposures to TCS and TCC through dust ingestion were estimated for various age groups with 95% CI daily intake doses ranging from (0.032-0.070) to (0.340-0.740) and from (0.017-0.033) to (0.175-0.345) ng kg-bw^-1 d^-1 for adults and infants respectively. Although our derived values were much lower than reference doses, more comprehensive risk assessment considering multiple exposure pathways of TCS and TCC is needed.

PI3K/Akt/FoxO pathway mediates glycolytic metabolism in HepG2 cells exposed to triclosan (TCS)

Triclosan (TCS) has been widely used as an antibacterial agent for the last several decades in personal care products. The toxicological effect of TCS has attracted more and more attention of researchers. The purpose of this study is to evaluate the cytotoxic effects of TCS in HepG2 cells and to elucidate the molecular mechanism focusing on regulation of the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt)/forkhead box O (FoxO) pathway in the glycolytic metabolism. In this study, we evaluated the adverse effect of TCS exposure on cell viability, reactive oxygen species (ROS) generation, superoxide dismutase (SOD) activity and mitochondrial membrane potential (MMP). In addition, the glycolysis process in HepG2 cells exposed to TCS was examined in terms of glucose consumption, lactate production and ATP generation. Furthermore, Affymetrix Human U133 plus 2.0 gene chips and gene function enrichment analysis were conducted to screen differential expression genes (DEGs) and potential signaling pathway. Expressions of the glycolysis-related proteins were measured and quantified with Western Blotting. The results showed that TCS could suppress the cell viability, induce oxidative stress, and cause mitochondrial damage. In addition, TCS exposure promoted the glycolysis process, as manifested by accelerated conversion of glucose to lactate and increased energy release. Western Blotting results confirmed that the expression levels of glycolysis related proteins were significantly elevated. The PI3K/Akt/FoxO pathway was identified to play a pivot role in TCS-induced glycolysis, which was further confirmed by inhibitor tests using specific inhibitors LY294002 and MK2206. In general, TCS can induce oxidative stress, cause oxidative damages and promote glycolysis in HepG2 cells, which was mediated by the PI3K/Akt/FoxO pathway.