Widespread occurrence of bisphenol A diglycidyl ethers, p-hydroxybenzoic acid esters (parabens), benzophenone type-UV filters, triclosan, and triclocarban in human urine from Athens, Greece

Induction of chromosomal aberrations and micronuclei by 2-hydroxy-4-methoxybenzophenone (oxybenzone) in human lymphocytes

Oxybenzone or benzophenone-3 (2-hydroxy-4-methoxybenzophenone; BP-3) is a filter used in a variety of personal care products for protection of human skin and hair from damage by ultraviolet radiation. BP-3 is suspected to exhibit endocrine disruptive properties. Indeed, it was found to be able to interact with the endocrine system causing alteration of its homeostasis, with consequent adverse health effects. Moreover, it is ubiquitously present in the environment, mostly in aquatic ecosystems, with consequent risks to the health of aquatic organisms and humans. In the present study, we analyzed the cytogenetic effects of BP-3 on human lymphocytes using in vitro chromosomal aberrations and micronuclei assays. Blood samples were obtained from five healthy Italian subjects. Lymphocyte cultures were exposed to five concentrations of BP-3 (0.20, 0.10, 0.05, 0.025, and 0.0125 μg/mL) for 24 and 48 h (for chromosomal aberrations and micronuclei tests, respectively). The concentration of 0.10 µg/mL represents the acceptable/tolerable daily intake reference dose established by European Union, whereas 0.20, 0.05, 0.025, and 0.0125 µg/mL represent multiple and sub-multiple of this concentration value. Our results reported cytogenetic effects of BP-3 on cultured human lymphocytes in terms of increased micronuclei and chromosomal aberrations' frequencies at all tested concentrations, including concentrations lower than those established by European Union. Vice versa, after 48-h exposure, a significant reduction of the cytokinesis-block proliferation index value in cultures treated with BP-3 was not observed, indicating that BP-3 does not seem to produce effects on the proliferation/mitotic index when its concentration is equal to or less than 0.20 μg/mL.

The pH-dependent toxicity of triclosan to five aquatic organisms (Daphnia magna, Photobacterium phosphoreum, Danio rerio, Limnodrilus hoffmeisteri, and Carassius auratus)

Triclosan (TCS) is an antibacterial and antifungal agent widely used in personal care products, and it has been frequently detected in the aquatic environment. In the present study, the acute toxicity of TCS to Daphnia magna, Photobacterium phosphoreum, Danio rerio, and Limnodrilus hoffmeisteri was assessed under different pH conditions. Generally, TCS was more toxic to the four aquatic organisms in acidic medium. The LC₅₀ values for D. magna and D. rerio were smaller among the selected species, suggesting that D. magna and D. rerio were more sensitive to TCS. In addition, the oxidative stress-inducing potential of TCS was evaluated in Carassius auratus at three pH values. Changes of superoxide dismutase (SOD) and catalase (CAT) activity, glutathione (GSH) level, and malondialdehyde (MDA) content were commonly observed in all TCS exposure groups, indicating the occurrence of oxidative stress in the liver of C. auratus. The integrated biomarker response (IBR) index revealed that a high concentration of TCS induced great oxidative stress in goldfish under acidic condition. This work supplements the presently available data on the toxicity data of TCS, which would provide some useful information for the environmental risk assessment of this compound.

A fast and simple air-assisted liquid-liquid microextraction procedure for the simultaneous determination of bisphenols, parabens, benzophenones, triclosan, and triclocarban in human urine by liquid chromatography-tandem mass spectrometry

The increasing awareness and public concern with hazard exposure to endocrine-disrupting chemicals calls for methods capable to handle numerous samples in short analysis time. In this present study, a novel method combining air-assisted liquid-liquid microextraction and liquid chromatography coupled to mass spectrometry was developed and validated for the extraction, preconcentration, and determination of 7 bisphenols (bisphenol A, bisphenol S, bisphenol AP, bisphenol P, bisphenol F, bisphenol AF, bisphenol Z), 7 parabens (methyl-, ethyl-, propyl-, butyl-, benzyl-paraben, methyl-protocatechuic acid, and ethyl-protocatechuic acid), 5 benzophenones (benzophenone-1, benzophenone-2, benzophenone-3, benzophenone-8, and 4-hydroxybenzophenone), and two antimicrobials (triclosan and triclocarban) in human urine samples. Type and volume of solvent, extraction time (cycles), pH sample, ionic strength, agitation, and needle dimensions were evaluated. The matrix-matched calibration curves of all analytes were linear with correlation coefficients higher than 0.99 in the range level of 1.0-20.0 ng mL^-1. The relative standard deviation, precision, at three concentrations (1.0, 10.0 and 20.0 ng mL^-1) was lower than 15% with accuracy ranging from 90% to 114%. The biomonitoring capability of the new proposed method was confirmed with the analysis of 50 human urine samples randomly collected from Brazilian children. High urinary concentrations of several EDCs associated with usage of personal care products were found.

Urinary levels of triclosan and triclocarban in several Asian countries, Greece and the USA: Association with oxidative stress

Triclosan (TCS) and Triclocarban (TCC) are widely used as antimicrobial preservatives in personal care products (PCPs). Because of their potential for endocrine disrupting effects, human exposure to these chemicals is a concern. Biomonitoring studies of human exposure to TCS and TCC have shown widespread exposure of populations in western European countries and the USA. However, exposure to TCC and TCS by populations in Asian countries is less well known. In this study, concentrations of TCS and TCC were determined in human urine collected from seven Asian countries (China, India, Korea, Kuwait, Japan, Saudi Arabia, and Vietnam), and Greece and the USA. A total of 430 urine samples were analyzed for TCS and TCC, of which 355 (83%) and 82 (19%), respectively, contained measurable levels of these chemicals. The overall geometric mean [GM] concentrations of TCS and TCC, were 1.36 and 0.03ng/mL, respectively. The highest mean concentration of TCS was found in urine from China (100ng/mL) and the lowest concentration was found in urine from Vietnam (2.34ng/mL). We also analyzed urinary 8-OHdG, a marker of oxidative stress, to elucidate the association with TCS and TCC levels for samples from Saudi Arabia (n=130) and a positive correlation between Ln-transformed TCC levels and 8-OHdG was found, although this was not statistically significant. This is the first study to report urinary levels of TCS and TCC in several Asian countries, especially for Vietnam, Kuwait, and Japan.

Fate of triclocarban in agricultural soils after biosolid applications

Triclocarban [N-(4-chlorophenyl)-N-(3,4-dichlorophenyl) urea] (TCC) is an antimicrobial agent utilized in a variety of consumer products. It is commonly released into domestic wastewaters and upon treatment, it is known to accumulate in biosolids. This study examines the occurrence of TCC in biosolids and its long-term fate in biosolid-treated soils. TCC levels in the biosolids from a large waste water treatment plant (WWTP) over 2 years showed little variability at 18,800 ± 700 ng g^-1 dry wt. (mean ± SEM). Surface soil samples (top 10 cm) were collected from 26 commercial farms located in northern VA, US that had received biosolid applications from the WWTP. Samples were grouped as farms receiving no biosolids, farms with a single biosolid application, and those receiving multiple biosolid applications from 1992 to 2006. Our results illustrate that TCC soil residues remained years after biosolid application. The two most important parameters controlling TCC topsoil concentrations were the biosolid application rate and the period since the last application. No TCC removal was observed in farms where the time since biosolid application was between 7 and 9 months. TCC concentration analyzed 7 and 8 years after biosolid applications were 45.8 ± 6.1 and 72.4 ± 15.3 ng g^-1 dry wt., respectively, showing its persistence in soils and build-up upon multiple biosolid applications. A soil TCC half-life of 287.5 ± 45.5 days was estimated.

Exposure to benzophenones, parabens and triclosan among pregnant women in different trimesters

Humans are potentially exposed to many environmental pollutants, many of which may cause adverse health effects, especially to pregnant women and their fetuses. In this study, 11 environmental pollutants from three different chemical classes, including benzophenones, parabens and triclosan were measured in 627 urine samples collected from 209 pregnant women to evaluate exposure and trends as a function of pregnancy stage. Methylparaben (MeP), ethylparaben, propylparaben (PrP), butylparaben, 2,4-dihydroxybenzophenone (BP-1), 2-hydroxy-4-methoxybenzophenone (BP-3) and 4-hydroxybenzophenone were detected in >50% samples. The concentrations of BP-1 and BP-3 (Spearman's r=0.57, p<0.01) and those of MeP and PrP (Spearman's r=0.68, p<0.01) were found to be correlated. The urinary concentrations of BP-1 and BP-3 in the first trimester were significantly higher than those in the second or third trimester (Mann-Whitney U test, p<0.05). These findings provide valuable information for improving the prediction of maternal exposure to these emerging pollutants and for assessing their potential health risks to the mother as well as the offspring.

Occurrence of and human exposure to parabens, benzophenones, benzotriazoles, triclosan and triclocarban in outdoor swimming pool water in Changsha, China

The entry of personal care products (PCPs) into the environment has, in turn, caused negative influences to human health. Public swimming pools are places that have attracted increasing concerns. In this article, 35 outdoor swimming pools in Changsha City (China) were examined in view of the occurrence of 22 target PCPs contaminants, which fall into four categories: preservatives, UV filters, anticorrosion agents, and antimicrobials. Out of them, 16 compounds were detected in the collected samples. The preservatives was the most dominant category, with methyl paraben being the top compound (a.v. 0.85μg/L) followed by p-hydroxybenzoic acid (a.v. 0.13μg/L) and 1H-benzotriazole (a.v. 0.14μg/L). The correlations among 22 PCPs and their four categories were evaluated using the nonparametric Spearman correlations analysis. In the source tracing investigation, the level of PCPs in swimming pools was determined to be primarily associated with the consumption of these products while weakly related to the filling waters. The quantitative risk assessment revealed that the PCPs concentrations were at a safe level.

Potential Developmental and Reproductive Impacts of Triclocarban: A Scoping Review

Triclocarban (TCC) is an antimicrobial agent used in personal care products. Although frequently studied with another antimicrobial, triclosan, it is not as well researched, and there are very few reviews of the biological activity of TCC. TCC has been shown to be a possible endocrine disruptor, acting by enhancing the activity of endogenous hormones. TCC has been banned in the US for certain applications; however, many human populations, in and outside the US, exhibit exposure to TCC. Because of the concern of the health effects of TCC, we conducted a scoping review in order to map the current body of literature on the endocrine, reproductive, and developmental effects of TCC. The aim of this scoping review was to identify possible endpoints for future systematic review and to make recommendations for future research. A search of the literature until August 2017 yielded 32 relevant studies in humans, rodents, fish, invertebrates, and in vitro. Based on the robustness of the literature in all three evidence streams (human, animal, and in vitro), we identified three endpoints for possible systematic review: estrogenic activity, androgenic activity, and offspring growth. In this review, we describe the body of evidence and make recommendations for future research.

Daily intake and hazard index of parabens based upon 24 h urine samples of the German Environmental Specimen Bank from 1995 to 2012

In recent years, exposure to parabens has become more of a concern because of evidence of ubiquitous exposure in the general population, combined with evidence of their potency as endocrine disruptors. New human metabolism data from oral exposure experiments enable us to back calculate daily paraben intakes from urinary paraben levels. We report daily intakes (DIs) for six parabens based on 660 24 h urine samples from the German Environmental Specimen Bank collected between 1995 and 2012. Median DI values ranged between 1.1 μg/kg bw/day for iso-butyl paraben and 47.5 μg/kg bw/day for methyl paraben. The calculated DIs were compared with acceptable levels of exposure to evaluate the hazard quotients (HQs) that indicate that acceptable exposure is exceeded for values of >1. Approximately 5% of our study population exceeded this threshold for individual paraben exposure. The hazard index (HI) that takes into account the cumulative risk of adverse estrogenic effects was 1.3 at the 95th percentile and 4.4 at maximum intakes, mainly driven by n-propyl paraben exposure. HI values of >1 indicate some level of concern. However, we have to point out that we applied most conservative assumptions in the HQ/HI calculations. Also, major exposure reduction measures were enacted in the European Union after 2012.

Considering common sources of exposure in association studies - Urinary benzophenone-3 and DEHP metabolites are associated with altered thyroid hormone balance in the NHANES 2007-2008

Epidemiological studies have shown that thyroid hormone balances can be disrupted by chemical exposure. However, many association studies have often failed to consider multiple chemicals with possible common sources of exposure, rendering their conclusions less reliable. In the 2007-2008 National Health and Nutrition Examination Survey (NHANES) from the U.S.A., urinary levels of environmental phenols, parabens, and phthalate metabolites as well as serum thyroid hormones were measured in a general U.S. population (≥12years old, n=1829). Employing these data, first, the chemicals or their metabolites associated with thyroid hormone measures were identified. Then, the chemicals/metabolites with possible common exposure sources were included in the analytical model to test the sensitivities of their association with thyroid hormone levels. Benzophenone-3 (BP-3), bisphenol A (BPA), and a metabolite of di(2-ethylhexyl) phthalate (DEHP) were identified as significant determinants of decreased serum thyroid hormones. However, significant positive correlations were detected (p-value<0.05, r=0.23 to 0.45) between these chemicals/metabolites, which suggests that they might share similar exposure sources. In the subsequent sensitivity analysis, which included the chemicals/metabolite with potentially similar exposure sources in the model, we found that urinary BP-3 and DEHP exposure were associated with decreased thyroid hormones among the general population but BPA exposure was not. In association studies, the presence of possible common exposure sources should be considered to circumvent possible false-positive conclusions.

Benzophenone-type UV filters in surface waters: An assessment of profiles and ecological risks in Shanghai, China

Benzophenone-type UV filters (BP-UV filters) are frequently introduced into aquatic environment from several sources. The occurrence and fate of select BP-UV filters and their metabolites were investigated in this study. All target compounds were detected in water samples, except for 2, 3, 4-trihydroxybenzophenone (2, 3, 4-OH-BP). The concentration reached up 131ngL^-1 for 5-benzoyl-4-hydroxy-2-ethoxybenzenesulfonic acid (BP-4), 30.0ngL^-1 for 2-hydroxy-4-methoxybenzophenone (BP-3), and mean value of 158ngL^-1 for benzophenone (BP). Concentrations of BP-UV filters were not related to recreational waters but with high population frequencies. In addition, five BP-UV filters, namely 2,2',4,4'-tetrahydroxybenzophenone (BP-2), 2,3,4-OH-BP, 2,4-dihydroxybenzophenone (BP-1), 4-hydroxybenzophenone (4-OH-BP) and BP were investigated for probable sources, and found that they originate from BP-3 metabolism. There is a similar source for BP-3, BP-4, BP-1, 4-OH-BP and BP. Environmental risk assessment (ERA) showed that risk quotients (RQs) of BP-4, BP-3 and BP were 2.7, 0.8 and 0.5, respectively.

Comparison of methods for calculating the health costs of endocrine disrupters: a case study on triclosan

BACKGROUND

Socioeconomic analysis is currently used in the Europe Union as part of the regulatory process in Regulation Registration, Evaluation and Authorisation of Chemicals (REACH), with the aim of assessing and managing risks from dangerous chemicals. The political impact of the socio-economic analysis is potentially high in the authorisation and restriction procedures, however, current socio-economic analysis dossiers submitted under REACH are very heterogeneous in terms of methodology used and quality. Furthermore, the economic literature is not very helpful for regulatory purposes, as most published calculations of health costs associated with chemical exposures use epidemiological studies as input data, but such studies are rarely available for most substances. The quasi-totality of the data used in the REACH dossiers comes from toxicological studies.

METHODS

This paper assesses the use of the integrated probabilistic risk assessment, based on toxicological data, for the calculation of health costs associated with endocrine disrupting effects of triclosan. The results are compared with those obtained using the population attributable fraction, based on epidemiological data.

RESULTS

The results based on the integrated probabilistic risk assessment indicated that 4894 men could have reproductive deficits based on the decreased vas deferens weights observed in rats, 0 cases of changed T₃ levels, and 0 cases of girls with early pubertal development. The results obtained with the Population Attributable Fraction method showed 7,199,228 cases of obesity per year, 281,923 girls per year with early pubertal development and 88,957 to 303,759 cases per year with increased total T₃ hormone levels. The economic costs associated with increased BMI due to TCS exposure could be calculated. Direct health costs were estimated at €5.8 billion per year.

CONCLUSIONS

The two methods give very different results for the same effects. The choice of a toxicological-based or an epidemiological-based method in the socio-economic analysis will therefore significantly impact the estimated health costs and consequently the political risk management decision. Additional work should be done for understanding the reasons of these significant differences.

Exposure to bisphenols and phthalates and association with oxidant stress, insulin resistance, and endothelial dysfunction in children

BACKGROUND

The health effects of bisphenol A (BPA) and di-(2-ethylhexyl) phthalate (DEHP) have been studied extensively in children. The impact of other chemicals in these two classes has not been investigated as fully.

METHODS

We conducted a cross-sectional pilot study of 10-13 y old healthy children. We assessed descriptive, univariable, and multivariable associations of urinary metabolites of bisphenols and phthalates with oxidant stress, insulin resistance, body mass, and endothelial dysfunction. Possible associations with brachial artery distensibility, pulse wave velocity (markers of vascular stiffness), and serum endothelial cell-derived microparticle levels were also assessed.

RESULTS

We enrolled 41 participants, 12.1 ± 1.0 y, most of whom were Mexican Americans (42%) or other Hispanics (34%). Increased BPA levels were associated with increased levels of F2-isoprostane (ng/ml) (P = 0.02), with a similar trend for DEHP metabolites. Each log unit increase of high molecular weight (HMW) phthalate metabolites was associated with a 0.550 increase in Homeostatic Model Assessment of insulin resistance (HOMA-IR) units (P = 0.019) and altered circulating levels of activated endothelial cell-derived microparticles (% per ml) (P = 0.026). Bisphenol S (BPS), a replacement for BPA, was associated with increased albumin (mg):creatinine (g) ratio (P = 0.04). Metabolites of HMW phthalates were also associated with decreased brachial artery distensibility (P = 0.047).

CONCLUSION

Exposure to bisphenols and phthalates, including a BPA replacement, is associated with increased oxidant stress, insulin resistance, albuminuria, as well as disturbances in vascular function in healthy children.

Urinary concentrations of 25 phthalate metabolites in Brazilian children and their association with oxidative DNA damage

Exposure of humans to phthalates has received considerable attention due to the ubiquitous occurrence and potential adverse health effects of these chemicals. Nevertheless, little is known about the exposure of the Brazilian population to phthalates. In this study, concentrations of 25 phthalate metabolites were determined in urine samples collected from 300 Brazilian children (6-14years old). Further, the association between urinary phthalate concentrations and a biomarker of oxidative stress, 8-hydroxy-2'-deoxyguanosine (8OHDG), was examined. Overall, eleven phthalate metabolites were found in at least 95% of the samples analyzed. The highest median concentrations were found for monoethyl phthalate (mEP; 57.3ngmL^-1), mono-(2-ethyl-5-carboxypentyl) phthalate (mECPP; 52.8ngmL^-1), mono-isobutyl phthalate (mIBP; 43.8ngmL^-1), and mono-n-butyl phthalate (mBP; 42.4ngmL^-1). The secondary metabolites of di(2-ethylhexyl) phthalate (DEHP), and mEP, mIBP, and mBP were the most abundant compounds, accounting for >90% of the total concentrations. On the basis of the measured concentrations of urinary phthalate metabolites, we estimated daily intakes of the parent phthalates, which were 0.3, 1.7, 1.8, 2.1, and 7.2μg/kg-bw/day for dimethyl phthalate, di-n-butyl phthalate, diisobutyl phthalate, diethyl phthalate, and DEHP, respectively. Approximately one-quarter of the Brazilian children had a hazard index of >1 for phthalate exposures. Statistically significant positive associations were found between 8OHDG and the concentration of the sum of phthalate metabolites, sum of DEHP metabolites, mEP, mIBP, mBP, monomethyl phthalate, mono(3-carboxypropyl) phthalate, monobenzyl phthalate, monocarboxyoctyl phthalate, monocarboxynonyl phthalate, monoisopentyl phthalate, and mono-n-propyl phthalate. To the best of our knowledge, this is the first study to report the exposure of a Brazilian population to phthalates.

Acute toxicity variation of hydroxyl benzophenone UV filters during photoinduction-chlorination disinfection processes

Benzophenones (BPs), a group of widely used UV filters, exert multiple, significant toxicity effects. The 11 BPs were selected as target compounds, and the photobacterium acute toxicity test and an index for acute toxicity formation potential (ATFP) were used to evaluate the toxicity variation of BPs before and after a photoinduction-chlorination disinfection process. Orthogonal experiments were performed at different pH values and chlorine dosages. The characteristics of ATFP values for 11 BPs after a photoinduction-chlorination process can be summarized as follows: (1) The ATFPs decreased as the hydroxyl group number increased in BPs molecules. (2) For those BPs with the same hydroxyl group number, the ATFPs were higher when the hydroxyl groups were located at the 3- or 4-position than those at the 2-position; the BPs with hydroxyl groups distributed on two benzene rings had higher ATFPs than those on one ring. (3) Introducing a methoxyl group and sulfonic acid group into BP molecules increased the ATFP values. (4) The ATFPs were pH-dependent, the values of which were lowest at the neutral condition and highest at the acid condition. (5) The ATFPs increased and then decreased as the chlorine dosage increased. The results can be used as a reference to scientifically evaluate the environmental fate and potential risk of BPs in photoinduction-chlorination disinfection processes.

Migration of Parabens, Bisphenols, Benzophenone-Type UV Filters, Triclosan, and Triclocarban from Teethers and Its Implications for Infant Exposure

Parabens (p-hydroxybenzoic acid esters), bisphenols, benzophenone-type UV filters, triclosan, and triclocarban are used in a variety of consumer products, including baby teethers. Nevertheless, the exposure of infants to these chemicals through the use of teethers is still unknown. In this study, 59 teethers, encompassing three types, namely solid plastic, gel-filled, and water-filled (most labeled "bisphenol A-free"), were collected from the U.S. market and analyzed for 26 potential endocrine-disrupting chemicals (EDCs) from intact surfaces through migration/leaching tests performed with Milli-Q water and methanol. The total amount of the sum of six parent parabens (Σ₆ Parabens) leached from teethers ranged from 2.0 to 1990 ng, whereas that of their four transformation products (Σ₄ Parabens) ranged from 0.47 to 839 ng. The total amount of the sum of nine bisphenols (Σ₉ bisphenols) and 5 benzophenones (Σ₅ benzophenones) leached from teethers ranged from 1.93 to 213 ng and 0.59 to 297 ng, respectively. Triclosan and triclocarban were found in the extracts of teethers at approximately 10-fold less amounts than were bisphenols and benzophenones. Based on the amount leached into Milli-Q water, daily intake of these chemicals was estimated from the use of teethers by infants at 12 months of age. This is the first study to document the occurrence and migration of a wide range EDCs from intact surfaces of baby teethers.

Urinary Concentrations of the Antibacterial Agent Triclocarban in United States Residents: 2013-2014 National Health and Nutrition Examination Survey

Triclocarban is widely used as an antibacterial agent in personal care products, and the potential for human exposure exists. We present here the first nationally representative assessment of exposure to triclocarban among Americans ≥6 years of age who participated in the 2013-2014 National Health and Nutrition Examination Survey. We detected triclocarban at concentrations above 0.1 μg/L in 36.9% of 2686 urine samples examined. Triclocarban was detected more frequently in adolescents and adults than in children, and in non-Hispanic black compared to other ethnic groups. In univariate analysis, log-creatinine, sex, age, race, and body surface area (BSA) were significantly associated with the likelihood of having triclocarban concentrations above the 95^th percentile. In multiple regression models, persons with BSA at or above the median (≥1.86 m²) were 2.43 times more likely than others, and non-Hispanic black and non-Hispanic white were 3.71 times and 2.23 times more likely than "all Hispanic," respectively, to have urinary concentrations above the 95^th percentile. We found no correlations between urinary concentrations of triclocarban and triclosan, another commonly used antibacterial agent. Observed differences among demographic groups examined may reflect differences in physiological factors (i.e., BSA) as well as use of personal care products containing triclocarban.

Environmental occurrence and ecological risk assessment of organic UV filters in marine organisms from Hong Kong coastal waters

Organic UV filters, now considered to be emerging contaminants in aquatic ecosystems, are being intensively tracked in environmental waters worldwide. However, their environmental fate and impact of these contaminants on marine organisms remains largely unknown, especially in Asia. This work elucidates the occurrence and the ecological risks of seven UV filters detected in farmed fish, wild mussels and some other wild organisms collected from local mariculture farms in Hong Kong. For all of the organisms, ethylhexyl methoxycinnamate (EHMC) and octyl dimethyl p-aminobenzoic acid (OD-PABA) were the predominant contaminants with the highest concentrations up to 51.3 and 24.1ng/g (dw), respectively; lower levels were found for benzophenone-8 (BP-8), octocrylene (OC) and benzophenone-3 (BP-3) from <LOQ to <14.4ng/g (dw); 4-methylbenzylidene camphor (4-MBC) and 3-benzylidene camphor (3-BC) were rarely detected. Additionally, the detection frequencies and measured concentrations of all targets were clearly higher in mussels than in fish. Spatial distribution of studied UV filters indicated a positive correlation between their measured concentrations and the anthropogenic activities responsible for their direct emission. The ecological risk assessment specific to the marine aquatic environment was carried out. The risk quotient (RQ) values of EHMC and BP-3 were calculated as 3.29 and 2.60, respectively, indicating these two UV filters may pose significant risks to the marine aquatic environment.

Urinary biomarkers of exposure to 57 xenobiotics and its association with oxidative stress in a population in Jeddah, Saudi Arabia

Oxidative stress arises from excessive free radicals in the body and is a trigger for numerous diseases, such as cancer and atherosclerosis. Elevated exposure to environmental chemicals can contribute to oxidative stress. The association between exposure to xenobiotics and oxidative stress, however, has rarely been studied. In this study, urinary concentrations of 57 xenobiotics (antimicrobials, parabens, bisphenols, benzophenones, and phthalates metabolites) were determined in a population from Jeddah, Saudi Arabia, to delineate association with the oxidative stress biomarker, 8-hydroxy-2'-deoxyguanosine (8OHDG). We collected 130 urine samples and analyzed for 57 xenobiotics using liquid chromatography-tandem mass spectrometry (LC/MS/MS) methods. The association between unadjusted and creatinine- or specific gravity-adjusted concentrations of xenobiotics and 8OHDG was examined by Pearson correlations and multiple regression analysis. High concentrations of mCPP (a metabolite of di-n-octyl phthalate; DnOP) and mCMHP (a metabolite of diethylhexyl phthalate; DEHP) were found in urine. In addition, the concentrations of bisphenol S (BPS) were higher than those of bisphenol A (BPA). The concentrations of metabolites of DEHP, phthalic acid, BPA, BPS, and methyl-protocatechuic acid were significantly associated with 8OHDG. This is the first biomonitoring study to report exposure of the Saudi population to a wide range of environmental chemicals and provides evidence that environmental chemical exposures contribute to oxidative stress.

Triclosan: A review on systematic risk assessment and control from the perspective of substance flow analysis

Triclosan (TCS) is a broad spectrum antibacterial agent mainly used in Pharmaceutical and Personal Care Products. Its increasing use over recent decades have raised its concentration in the environment, with commonly detectable levels found along the food web-from aquatic organisms to humans in the ecosystem. To date, there is shortage of information on how to investigate TCS's systematic risk on exposed organisms including humans, due to the paucity of systematic information on TCS flows in the anthroposphere. Therefore, a more holistic approach to mass flow balancing is required, such that the systematic risk of TCS in all environmental matrices are evaluated. From the perspective of Substance Flow Analysis (SFA), this review critically summarizes the current state of knowledge on TCS production, consumption, discharge, occurrence in built and natural environments, its exposure and metabolism in humans, and also the negative effects of TCS on biota and humans. Recent risk concerns have mainly focused on TCS removal efficiencies and metabolism, but less attention is given to the effect of mass flows from source to fate during risk exposure. However, available data for TCS SFA is limited but SFA can derive logical systematic information from limited data currently available for systematic risk assessment and reduction, based on mass flow analysis. In other words, SFA tool can be used to develop a comprehensive flow chart and indicator system for the risk assessment and reduction of TCS flows in the anthroposphere, thereby bridging knowledge gaps to streamline uncertainties related to policy-making on exposure pathways within TCS flow-lines. In the final analysis, specifics on systematic TCS risk assessment via SFA, and areas of improvement on human adaptation to risks posed by emerging contaminants are identified and directions for future research are suggested.

Accumulation profiles of parabens and their metabolites in fish, black bear, and birds, including bald eagles and albatrosses

Although several studies have reported the ubiquitous occurrence of parabens in human specimens and the environment, little is known about the accumulation of these estrogenic chemicals in fish and birds. In this study, accumulation profiles of six parabens and their metabolites were determined in 254 tissue (including liver, kidney, egg, and plasma) samples from 12 species of fish and seven species of birds collected from inland, coastal, and remote aquatic ecosystems. In addition, liver and kidney tissues from black bears were analyzed. Methyl paraben (MeP) was found in a majority of the tissues, with the highest concentration (796ng/g (wet weight [wet wt])) found in the liver of a bald eagle from Michigan. 4-Hydroxy benzoate (HB) was the major metabolite, found in 91% of the tissue samples analyzed at concentrations as high as 68,600ng/g, wet wt, which was found in the liver of a white-tailed sea eagle from the Baltic Sea coast. The accumulation pattern of MeP and 4-HB varied, depending on the species. The mean concentrations of MeP measured in fishes from Michigan, New York, and Florida waters were <2.01 (fillet), 152 (liver), and 32.0 (liver) ng/g, wet wt, respectively, and the corresponding 4-HB concentrations were 39.5, 10,500, and 642ng/g, wet wt. The mean hepatic and renal concentrations of 4-HB in black bears were 1,720 and 1,330ng/g, wet wt, respectively. The concentrations of MeP and 4-HB were significantly positively correlated with each other in various tissues and species, which suggested a common source of exposure to these compounds in fish and birds. Trace concentrations of MeP and 4-HB also were found in the tissues of albatrosses from Midway Atoll, Northwestern Pacific Ocean, which suggested widespread distribution of these compounds in the marine environment.

Determination of endocrine-disrupting chemicals in human milk by dispersive liquid–liquid microextraction

Aim: Human populations are widely exposed to numerous so-called endocrine-disrupting chemicals, exogenous compounds able to interfere with the endocrine system. This exposure has been associated with several health disorders. New analytical procedures are needed for biomonitoring these xenobiotics in human matrices. A quick and inexpensive methodological procedure, based on sample treatment by dispersive liquid–liquid microextraction, is proposed for the determination of bisphenols, parabens and benzophenones in samples. Results: LOQs ranged from 0.4 to 0.7 ng ml-1 and RSDs from 4.3 to 14.8%. Conclusion: This methodology was satisfactorily applied in the simultaneous determination of a wide range of endocrine-disrupting chemicals in human milk samples and is suitable for application in biomonitoring studies.

Urinary benzophenone concentrations and their association with demographic factors in a South Korean population

Benzophenone (BP) and its derivatives are widely used in various cosmetics, personal care products, and food packaging ink. The use of BP has raised concerns about the potential health risks associated with its endocrine-disrupting effects. This study evaluated urinary concentrations of BP derivatives in a national sample of the South Koreans population aged 6-89 years. From July to September in each 2010 and 2011, 1576 urine samples were collected. Urinary concentrations of benzophenone-1 (BP-1), benzophenone-2 (BP-2), benzophenone-3 (BP-3), benzophenone-4 (BP-4), benzophenone-8 (BP-8), and 4-hydroxybenzophenone (4-OH-BP) were analyzed using liquid chromatography-mass spectrometry. The detection rate for BP-1 and 4-OH-BP were 56% [limit of detection (LOD) 0.59ng/mL] and 88% (LOD 0.04ng/mL), respectively, whereas those for BP-2, BP-3, BP-4, and BP-8 were all below 25%. The geometric means of urinary BP-1 and 4-OH-BP concentrations were 1.24ng/mL and 0.45ng/mL, respectively. Multiple linear regression analysis indicated that concentrations of BP-1 in and of 4-OH-BP in adults were associated with sex and age. The BP-1 and 4-OH-BP concentration of children and adolescents was associated with sex, age, income, and current area of residence. The correlation was observed between urinary concentrations of BP derivatives, which is an important indication of exposure biomarkers and the metabolic pathways from BP-3. This is the first national study to evaluate the presence of BP derivatives in urine samples from the South Korean population, stratified by demographic factors.

Occurrence of bisphenols, bisphenol A diglycidyl ethers (BADGEs), and novolac glycidyl ethers (NOGEs) in indoor air from Albany, New York, USA, and its implications for inhalation exposure

Bisphenols, bisphenol A diglycidyl ethers (BADGEs), and novolac glycidyl ethers (NOGEs) are used in the production of epoxy resins and polycarbonate plastics. Despite the widespread application of these chemicals in household products, studies on their occurrence in indoor air are limited. In this study, 83 indoor air samples were collected in 2014 from various locations in Albany, New York, USA, to determine the concentrations of bisphenols, BADGEs (refer to BADGE and its derivatives), and NOGEs (refer to NOGE and its derivatives) and to calculate inhalation exposure to these compounds. Among eight bisphenols measured, BPA, BPF, and BPS were found in bulk air (i.e., vapor plus particulate phases), at geometric mean (GM) concentrations of 0.43, 0.69 and 0.09 ng m(-3), respectively. Among 11 BADGEs and NOGEs determined, BADGE·2H2O was the predominant compound found in indoor air (detection rate [DR]: 85.5%), at concentrations as high as 6.71 ng m(-3). Estimation of inhalation exposure to these chemicals for various age groups showed that teenagers had the highest exposure doses to BPA, BPF, BPS, and BADGE·2H2O at 5.91, 9.48, 1.24, and 3.84 ng day(-1), respectively. The body weight-normalized estimates of exposure were the highest for infants, with values at 0.24, 0.39, 0.05, and 0.16 ng kg bw(-1) day(-1) for BPA, BPF, BPS, and BADGE·2H2O, respectively. This is the first survey to report inhalation exposure to bisphenols, BADGEs, and NOGEs.

The Association Between Urinary Benzophenone Concentrations and Personal Care Product Use in Korean Adults

Benzophenone (BP) derivatives are widely used in personal care products (PCPs) for protection from ultraviolet radiation. Because of their broad applications, BP derivatives have been found in various human bodily fluids. In the present study, we investigated the relationship between urinary concentrations of BP derivatives and PCP use in Korean adults. A urinary BP biomonitoring survey was conducted in Korea by the Ministry of Food and Drug Safety in 2014. BP derivatives (BP-1, BP-3, and 4-OH-BP) were measured in urine samples from 168 Korean adults (mean age, 43.2 ± 15.4 years) by high-performance liquid chromatography coupled with triple quadrupole tandem mass spectrometry. Information about the use of PCPs in the past 7 days was obtained by direct interviews. The mean levels of BP-1, BP-3, and 4-OH-BP were 0.87, 5.87, and 0.13 ng/g creatinine, respectively. The geometric mean levels of BP-1, BP-3, and 4-OH-BP were significantly higher in female than those in male. The medians of the urinary concentration of BP derivatives were significantly higher among users of the following PCPs than those in non-users; the PCPs included sunscreen, skin care products, functional cosmetics, makeup base, makeup, lip cosmetics, eye cosmetics, color cosmetics, perfume products, and nail products. A regression analysis revealed a significant linear association between urinary BP-3 concentrations and the number of additional cosmetic products used. These findings provide evidence of a positive association between exposure to PCPs and urinary BP derivative concentrations in Korean adults.

Urinary concentrations of parabens and their association with demographic factors: A population-based cross-sectional study

Parabens are broad-spectrum antimicrobial agents used in a range of consumer products, including personal care products, cosmetics, and food. Recently, the widespread use of parabens has raised concerns about the potential health risks associated with their endocrine-disrupting effect. In the present study, 2541 urine samples were collected and analyzed by liquid chromatography-mass spectrometry for the determination of the concentrations of methyl paraben (MeP), ethyl paraben (EtP), propyl paraben (PrP) and butyl paraben (BuP). The detection rate and geometric mean concentrations of parabens in the general population followed the order MeP (97.7%; 116ng/mL)>EtP (97.2%; 24.7ng/mL)>PrP (96.7%; 11.0ng/mL)>BuP (83.5%; 1.13ng/mL). The composition profiles showed that MeP and EtP accounted for >90% of the urinary paraben concentration. We performed statistical analysis in order to evaluate differences between demographic variables and urinary concentrations. Our results showed that adjusted proportional change of MeP, PrP, and BuP in adults were 2.67-6.13 times higher in females than in males. The urinary concentrations of PrP in adults increased significantly with age. The adjusted proportional changes of MeP and PrP in adults were associated with increased body mass index (BMI). The adjusted proportional changes of BuP and PrP in children and adolescents were 1.44 and 1.69 times higher in females than in males. However, there was no clear association between paraben concentrations and demographic variables in the children and adolescents groups. The estimated daily intake (EDIurine) of MeP and EtP in adults were 301μg/kg bw/day, which is lower than the acceptable daily intake (ADI; 10mg/kg bw/day). In summary, our results revealed that the general population in Korea was exposed to parabens during 2009-2010, and most Koreans are exposed to parabens. The urinary levels of parabens varied by age group with demographic factors in the Korean population. The results of study may be used to establish a nationally representative baseline of exposure to parabens in risk assessment.

Occurrence of phthalate diesters (phthalates), p-hydroxybenzoic acid esters (parabens), bisphenol A diglycidyl ether (BADGE) and their derivatives in indoor dust from Vietnam: Implications for exposure

Phthalate diesters (phthalates), esters of p-hydroxybenzoic acid (parabens), and bisphenol A diglycidyl ether (BADGE) are used in personal care products, food packages, household products, or pharmaceuticals. These compounds possess endocrine-disrupting potentials and have been reported to occur in the environment. Nevertheless, no previous studies have reported the occurrence of these compounds in indoor dust from Vietnam. In this study, nine phthalates, six parabens, and four BADGEs were determined in indoor dust samples collected from Hanoi, Hatinh, Hungyen, and Thaibinh, in Vietnam. Total concentrations of phthalates, parabens, and BADGEs in indoor dust ranged from 3440 to 106,000 ng/g (median: 22,600 ng/g), 40-840 ng/g (median: 123 ng/g), and 23 to 1750 ng/g (median: 184 ng/g), respectively. Based on the measured median concentration of phthalates, parabens, and BADGEs in indoor dust, we estimated human exposure doses to these compounds through indoor dust ingestion for various age groups. The exposure doses to phthalates, parabens, and BADGEs decreased with age and ranged from 19.4 to 90.4 ng/kg-bw/d, 0.113-0.528 ng/kg-bw/d, and 0.158-0.736 ng/kg-bw/d, respectively. This is the first study on the occurrence and human exposure of phthalates, parabens, and BADGEs in indoor dust from Vietnam.

Couples' urinary concentrations of benzophenone-type ultraviolet filters and the secondary sex ratio

The secondary sex ratio (SSR), defined as the ratio of males to females at birth, has been investigated in relation to endocrine disruptors to search for environmental toxicants perturbing human sex selection. Benzophenone (BP)-type ultraviolet (UV) filters, which are used in sunscreens and personal care products, have been reported to exert estrogenic and anti-androgenic activities. This study aimed to evaluate the association between maternal, paternal, and couple urinary concentrations of BP-type UV filters and the SSR, given the absence of previous investigation. The study cohort comprised 220 couples who were enrolled in the Longitudinal Investigation of Fertility and the Environment (LIFE) Study between 2005 and 2009 prior to conception and who had a singleton birth during the follow-up period. Couples' urinary concentrations of five BP-type UV filters (ng/mL) were measured using triple-quadrupole tandem mass spectrometry: 2,4-dihydroxybenzophenone (BP-1), 2,2',4,4'-tetrahydroxybenzophenone (BP-2), 2-hydroxy-4-methoxybenzophenone (BP-3), 2,2'-dihydroxy-4-methoxybenzophenone (BP-8), and 4-hydroxybenzophenone (4-OH-BP). Modified Poisson regression models were used to estimate the relative risks (RRs) of a male birth for each BP-type UV filter, after adjusting for potential confounders. When maternal and paternal urinary BP-type UV filter concentrations were modeled jointly, both maternal BP-2 (2nd vs 1st tertile, RR, 0.62, 95% confidence interval [CI], 0.43-0.91) and paternal BP-2 (3rd vs 1st tertile, RR, 0.67, 95% CI, 0.45-0.99; p-trend, 0.04) were significantly associated with an excess of female births. Contrarily, maternal 4-OH-BP was significantly associated with an excess of male births (2nd vs 1st tertile, RR, 1.87, 95% CI, 1.27-2.74; 3rd vs 1st tertile, RR, 1.80, 95% CI, 1.13-2.87; p-trend, 0.02). Our findings provide the first evidence suggesting that BP-type UV filters may affect the SSR. However, future corroboration is needed, given the exploratory design of this study.

Exposure of Preschool-Age Greek Children (RHEA Cohort) to Bisphenol A, Parabens, Phthalates, and Organophosphates

Phthalate esters (PEs), bisphenol A (BPA), and parabens (PBs), which are used in numerous consumer products, are known for their endocrine disrupting properties. Organophosphate chemicals (OPs), which form the basis of the majority of pesticides, are known for their neurotoxic activity in humans. All of these chemicals are associated with health problems to which children are more susceptible. Once they enter the human body, PEs, BPA, PBs, and OPs are metabolized and/or conjugated and finally excreted via urine. Hence, human exposure to these substances is examined through a determination of the urinary concentrations of their metabolites. This study assessed the exposure of Greek preschool-age children to PEs, BPA, PBs, and OPs by investigating the urinary levels of seven PEs metabolites, six PBs, BPA, and six dialkyl phosphate metabolites in five-hundred samples collected from 4-year-old children, subjects of the "RHEA" mother-child cohort in Crete, Greece. Daily intake of endocrine disruptors, calculated for 4 year old children, was lower than the corresponding daily intake for 2.5 year old children, which were determined in an earlier study of the same cohort. In some cases the daily intake levels exceeded the U.S. Environmental Protection Agency Tolerable Daily Intake (TDI) values and the EFSA Reference Doses (RfD) (e.g., for di-2-ethyl-hexyl phthalate, 3.6% and 1% of the children exceeded RfD and TDi, respectively). Exposure was linked to three main sources: PEs-BPA to plastic, PBs-diethyl phthalate to personal hygiene products, and OPs to food.

Occurrence and Profile Characteristics of the Pesticide Imidacloprid, Preservative Parabens, and Their Metabolites in Human Urine from Rural and Urban China

Knowledge of human exposure to imidacloprid, the most extensively used insecticide, and para-hydroxybenzoic acid esters (parabens), the most extensively used preservative, is insufficient. In this study, 295 urine samples collected from subjects in rural and urban areas in China were analyzed for imidacloprid and four parabens (namely, methyl paraben, ethyl paraben, propyl paraben, and butyl paraben) as well as their major metabolites (namely, 6-chloronicotinic acid (6-ClNA) and para-hydroxybenzoic acid (p-HB)). Imidacloprid was detected in 100% of the urine samples from rural Chinese subjects and 95% of the urine samples from urban Chinese subjects. Concentrations of urinary imidacloprid detected in rural Chinese subjects (geometric mean (GM) = 0.18 ng/mL) were slightly higher than those detected in urban Chinese subjects (GM = 0.15 ng/mL) when the effect of pesticide spraying was excluded. However, concentrations of urinary imidacloprid detected in rural adults increased significantly in the subsequent days of pesticide spraying (GM = 0.62 ng/mL), which could return to the normal levels within 3 days. In contrast, concentrations of urinary parabens detected in rural Chinese subjects (GM = 6.90 ng/mL) were lower than that in urban Chinese subjects (GM = 30.5 ng/mL). In addition, the metabolism characteristics of imidacloprid to 6-ClNA and parabens to p-HB were discussed preliminarily.

Use of pooled samples to assess human exposure to parabens, benzophenone-3 and triclosan in Queensland, Australia

Parabens, benzophenone-3 and triclosan are common ingredients used as preservatives, ultraviolet radiation filters and antimicrobial agents, respectively. Human exposure occurs through consumption of processed food and use of cosmetics and consumer products. The aim of this study was to provide a preliminary characterisation of exposure to selected personal care product chemicals in the general Australian population. De-identified urine specimens stratified by age and sex were obtained from a community-based pathology laboratory and pooled (n=24 pools of 100). Concentrations of free and total (sum of free plus conjugated) species of methyl, ethyl, propyl and butyl paraben, benzophenone-3 and triclosan were quantified using isotope dilution tandem mass spectrometry; with geometric means 232, 33.5, 60.6, 4.32, 61.5 and 87.7ng/mL, respectively. Age was inversely associated with paraben concentration, and females had concentrations approximately two times higher than males. Total paraben and benzophenone-3 concentrations are significantly higher than reported worldwide, and the average triclosan concentration was more than one order of magnitude higher than in many other populations. This study provides the first data on exposure of the general Australian population to a range of common personal care product chemical ingredients, which appears to be prevalent and warrants further investigation.

Metabolism and elimination of methyl, iso- and n-butyl paraben in human urine after single oral dosage

Parabens are used as preservatives in personal care and consumer products, food and pharmaceuticals. Their use is controversial because of possible endocrine disrupting properties. In this study, we investigated metabolism and urinary excretion of methyl paraben (MeP), iso-butyl paraben (iso-BuP) and n-butyl paraben (n-BuP) after oral dosage of deuterium-labeled analogs (10 mg). Each volunteer received one dosage per investigated paraben separately and at least 2 weeks apart. Consecutive urine samples were collected over 48 h. In addition to the parent parabens (free and conjugated) which are already used as biomarkers of internal exposure and the known but non-specific metabolites, p-hydroxybenzoic acid (PHBA) and p-hydroxyhippuric acid (PHHA), we identified new, oxidized metabolites with hydroxy groups on the alkyl side chain (3OH-n-BuP and 2OH-iso-BuP) and species with oxidative modifications on the aromatic ring. MeP represented 17.4 % of the dose excreted in urine, while iso-BuP represented only 6.8 % and n-BuP 5.6 %. Additionally, for iso-BuP, about 16 % was excreted as 2OH-iso-BuP and for n-BuP about 6 % as 3OH-n-BuP. Less than 1 % was excreted as ring-hydroxylated metabolites. In all cases, PHHA was identified as the major but non-specific metabolite (57.2-63.8 %). PHBA represented 3.0-7.2 %. For all parabens, the majority of the oral dose captured by the above metabolites was excreted in the first 24 h (80.5-85.3 %). Complementary to the parent parabens excreted in urine, alkyl-chain-oxidized metabolites of the butyl parabens are introduced as valuable and contamination-free biomarkers of exposure.

Reproductive endocrine-disrupting effects of triclosan: Population exposure, present evidence and potential mechanisms

Triclosan has been used as a broad-spectrum antibacterial agent for over 40 years worldwide. Increasing reports indicate frequent detection and broad exposure to triclosan in the natural environment and the human body. Current laboratory studies in various species provide strong evidence for its disrupting effects on the endocrine system, especially reproductive hormones. Multiple modes of action have been suggested, including disrupting hormone metabolism, displacing hormones from hormone receptors and disrupting steroidogenic enzyme activity. Although epidemiological studies on its effects in humans are mostly negative but conflicting, which is typical of much of the early evidence on the toxicity of EDCs, overall, the evidence suggests that triclosan is an EDC. This article reviews human exposure to triclosan, describes the current evidence regarding its reproductive endocrine-disrupting effects, and discusses potential mechanisms to provide insights for further study on its endocrine-disrupting effects in humans.

Effects of triclosan and triclocarban on the growth inhibition, cell viability, genotoxicity and multixenobiotic resistance responses of Tetrahymena thermophila

The information about adverse effects of emerging contaminants on aquatic protozoa is very scarce. The growth inhibition effect, cell viability, genotoxicity and multixenobiotic resistance (MXR) responses of two commonly used antimicrobial agents, triclosan (TCS) and triclocarban (TCC) to protozoan Tetrahymena thermophila were investigated in this study. The results revealed that TCS and TCC can inhibit the growth of T. thermophila with 24h EC50 values of 1063 and 295μgL(-1), respectively. The impairment of plasma membrane was observed after 2h exposure of TCS or TCC at the level of mg/L. Furthermore, it is noticeable that at environmentally relevant concentration (1.0μgL(-1)), both TCS and TCC can lead to statistically significant DNA damage in T. thermophila, while the inhibition of growth and change of cell viability cannot be observed. Our results firstly provide the evidence for genotoxic effects of TCS and TCC on the freshwater protozoan. Additionally, both TCS and TCC were found to inhibit the efflux transporter activities, with the inhibitory potencies of 39% and 40% (using verapamil as a model inhibitor), respectively. Particularly, TCC could significantly down-regulate the expression of MXR related gene Abcb15, which encodes the membrane efflux protein that acting as P-gp in T. thermophila. The results raise the awareness of potential aquatic ecological and human health risks from the exposure of TCS and TCC, as they might potentiate the toxic effects by chemosensitizing with co-existing toxicants.

Occurrence and human exposure of parabens and their chlorinated derivatives in swimming pools

As an emerging group of endocrine-disrupting chemicals, parabens have attracted growing attention due to their potential effects on human health. In the present study, the occurrence and distribution of eight parabens, four chlorinated parabens, and their common hydrolysis product, p-hydroxybenzoic acid (PHBA), were investigated in 39 swimming pools in Beijing, China. Methyl paraben and propyl paraben were the predominant compounds in swimming pools, accounting for 91.2 % of the total parabens. It is noteworthy that octyl paraben, a paraben with longer chain, was firstly detected in this study. There were several factors affecting the levels of parabens among the 39 swimming pools. The concentrations of parabens and chlorinated derivatives detected in indoor pools (144 ng L(-1)) were roughly 20-fold higher than those in outdoor pools (6.78 ng L(-1)). Hotel pools appear to present higher level of target compounds (361 ng L(-1)) than that in health club (228 ng L(-1)), municipal (130 ng L(-1)), school (75.6 ng L(-1)), and community pools (63.0 ng L(-1)). Moreover, the level of these compounds in pools during weekends (174 ng L(-1)) was much higher than that during weekdays (52.3 ng L(-1)). The dynamics of target compounds were also investigated to provide a general trend of the level of parabens in a school indoor swimming pool during a 14-week period. Human exposure assessment was conducted to estimate the potential risk of exposure to parabens and their chlorinated derivatives in swimming pools. Considering the total exposure dose of multiple parabens, human exposure to parabens from the water of swimming pools is negligible. However, the threat of these parabens to children in swimming pool should be concerned.

Acute toxicity of benzophenone-type UV filters for Photobacterium phosphoreum and Daphnia magna: QSAR analysis, interspecies relationship and integrated assessment

The hazardous potential of benzophenone (BP)-type UV filters is becoming an issue of great concern due to the wide application of these compounds in many personal care products. In the present study, the toxicities of BPs to Photobacterium phosphoreum and Daphnia magna were determined. Next, density functional theory (DFT) and comparative molecular field analysis (CoMFA) descriptors were used to obtain more detailed insight into the structure - activity relationships and to preliminarily discuss the toxicity mechanism. Additionally, the sensitivities of the two organisms to BPs and the interspecies toxicity relationship were compared. Moreover, an approach for providing a global index of the environmental risk of BPs to aquatic organisms is proposed. The results demonstrated that the mechanism underlying the toxicity of BPs to P. phosphoreum is primarily related to their electronic properties, and the mechanism of toxicity to D. magna is hydrophobicity. Additionally, D. magna was more sensitive than P. phosphoreum to most of the BPs, with the exceptions of the polyhydric BPs. Moreover, comparisons with published data revealed a high interspecies correlation coefficient among the experimental toxicity values for D. magna and Dugesia japonica. Furthermore, hydrophobicity was also found to be the most important descriptor of integrated toxicity. This investigation will provide insight into the toxicity mechanisms and useful information for assessing the potential ecological risk of BP-type UV filters.

Hepatic oxidative stress biomarker responses in freshwater fish Carassius auratus exposed to four benzophenone UV filters

Benzophenone (BP) type UV filters are widely used in many personal care products to protect human from UV irradiation. Despite the estrogenic potencies to fish and the environmental occurrences of BP derivatives in aquatic systems, little information is available regarding their effects on the antioxidant defense system in fish. In this work, the oxidative stress induced in livers of Carassius auratus was assessed using four biomarkers. The integrated biomarker response (IBR) was applied to assess the overall antioxidant status in fish. Moreover, liver tissues were also studied histologically. The changes in the activities of antioxidant enzymes and glutathione levels suggested that BPs generates oxidative stress in fish. The IBR index revealed that the hepatic oxidative toxicity followed the order BP-1>BP-2>BP-4>BP-3. The histopathological analysis revealed lesions caused by BPs. This investigation provides essential information for assessing the potential ecological risk of BP-type UV filters.