Urinary paraben concentrations and their associations with anthropometric measures of children aged 3 years

Tiny pills, big impacts: A systematic review on the endocrine disrupting effects of paediatric pharmaceuticals

Endocrine disrupting chemicals (EDCs) may impact children's health, with medicines as a possible exposure source. Objective: to assess the potential impact of substances in paediatric medications and essential oils on children as EDC. It is a systematic review of five databases including Medline following the PECOT approach. The review focused on publications about children exposed to medication (active ingredients or excipients of interest) and having developed clinical signs of endocrine dysfunction. Out of 946 studies identified, 28 studies were included. They revealed that parabens, lavender essential oils and anti-epileptics are the most identified pharmaceutical products. The reported outcomes relate to puberty, thyroid disorders, obesity and growth. The evidence indicates potential risks, but the overall quality of available data is limited. This systematic review exposes a lack of robust evidence linking paediatric medication exposure to EDC, predominantly relying on case reports. It cautions about potential conflicts of interest.

Short-Half-Life Chemicals: Maternal Exposure and Offspring Health Consequences-The Case of Synthetic Phenols, Parabens, and Phthalates

Phenols, parabens, and phthalates (PPPs) are suspected or known endocrine disruptors. They are used in consumer products that pregnant women and their progeny are exposed to daily through the placenta, which could affect offspring health. This review aims to compile data from cohort studies and in vitro and in vivo models to provide a summary regarding placental transfer, fetoplacental development, and the predisposition to adult diseases resulting from maternal exposure to PPPs during the gestational period. In humans, using the concentration of pollutants in maternal urine, and taking the offspring sex into account, positive or negative associations have been observed concerning placental or newborn weight, children's BMI, blood pressure, gonadal function, or age at puberty. In animal models, without taking sex into account, alterations of placental structure and gene expression linked to hormones or DNA methylation were related to phenol exposure. At the postnatal stage, pollutants affect the bodyweight, the carbohydrate metabolism, the cardiovascular system, gonadal development, the age of puberty, sex/thyroid hormones, and gamete quality, but these effects depend on the age and sex. Future challenges will be to explore the effects of pollutants in mixtures using models and to identify the early signatures of in utero exposure capable of predicting the health trajectory of the offspring.

Human exposure characteristics of pharmaceutical and personal care product chemicals and associations with dietary habits

Considering the widespread presence of pharmaceutical and personal care products (PPCPs) in the environment and their adverse health effects, human exposure to PPCPs has caused worldwide concern. However, there remains insufficient information on the exposure assessment of the Chinese population. Based on this, the exposure levels of 13 PPCPs in the urine samples of 986 Chinese adults were measured, aiming to provide information on the prevalence of PPCP occurrence and investigate potential correlations between PPCP exposure and obesity. Results showed that the detection rates of these compounds in urine ranged from 28.12 % to 98.58 %, with median concentrations ranging below the limit of detection to 10.58 ng mL-1. Methyl-paraben (MeP) was the most dominant paraben and had the highest urinary concentration (median = 10.12 ng mL-1), while 4-hydroxy-benzophenone (4-OH-BP) was the dominant benzophenone derivative (median = 0.22 ng mL-1). In antibacterials, the urinary concentration of triclosan (mean = 42.00 ng mL-1) was much higher than that of triclocarban (mean = 0.63 ng mL-1). PPCP concentrations were significantly associated with sex, age, body mass index, education level, and annual household income (p < 0.050). Regression analysis of dietary habits showed that seafood and tea consumption may be significant exposure sources of PPCP exposure (p < 0.050). Furthermore, individual exposure to MeP (odds ratio (OR) < 1, p = 0.002) and 4-OH-BP (OR < 1, p = 0.009) exhibited a significantly negative association with obesity in females. Also, analysis results from quantile g-computation and Bayesian kernel machine regression models demonstrated that an inverse correlation between PPCP mixture exposure and obesity was significant in females. This study reports the extensive prevalence of PPCP exposure among adults from China, and may provide crucial insights into PPCP exposure dynamics. More epidemiological studies are need in the future, with a thorough knowledge of PPCP exposure.

Exposure Profile and Characteristics of Parabens and Alkylphenols in Plasma among Rural Adults in Central China

Parabens and alkylphenols pose serious hazards to human health, yet there are few studies on their exposure profiles and health risks in rural Chinese populations. In this study, 804 participants were selected from the Henan Rural Cohort in mid-eastern China. The plasma levels of parabens (methylparaben, ethylparaben, propylparaben, butylparaben (BuP)) and alkylphenols (4-tert-butylphenol (4-t-BP), 4-tert-octylphenol (4-t-OP)) were analyzed via liquid chromatography-tandem mass spectrometry. Linear regression models were used to investigate factors that may influence pollutant exposure levels. The correlation between contaminants was assessed using Spearman's correlation. The human contaminant intake was estimated using the estimated daily intake (EDI). The health risk was assessed using the hazard quotient (HQ). The detection frequency of four parabens and two alkylphenols exceeded 75%, with median concentrations of 0.444, 0.067, 0.078, 0.053, 8.810, and 6.401 ng/mL, respectively. Significant correlations were observed between parabens, as well as between 4-t-BP and 4-t-OP. Regarding gender, paraben concentrations were higher in women than in men, except for BuP. The EDI for pollutants except 4-t-OP was lower than their respective tolerable/acceptable daily intake. In total, 85.70% of participants had 4-t-OP HQ > 1. A widespread exposure to parabens and alkylphenols among the rural population was found. The high health risks of alkylphenol exposure indicate that alkylphenols should be used with caution.

Occurrence and bioaccumulation of parabens and their metabolites in the biota from a subtropical freshwater river ecosystem: Implications for human exposure

Widespread occurrence of parabens in the environment has been documented, whereas little information is available about the occurrence and bioaccumulation of parabens in the aquatic biota. In this study, plants (n = 14), plankton (n = 20), and fish muscle (n = 89) samples were collected from Dongjiang River Basin and analyzed for nine parabens and two of their metabolites using ultra-high performance liquid chromatogram-tandem mass spectrometry. All the samples contained notable concentrations of parabens and the metabolites, and the total concentrations of parabens (Σp-PBs; sum of nine parent compounds) ranged from 0.40 to 776 ng/g dry wt. MeP, EtP, and PrP were the predominant parent compounds in both plankton and fish, while in plants, MeP, BzP and EtP were the top three abundant chemicals. As the predominant metabolite, 4-HB was detected in 99% aquatic biota samples analyzed with the highest concentration (24800 ng/g, dry wt) detected in an alga. Significantly positively correlations among the concentrations of MeP, BzP, EtP and 4-HB in the fish muscle were found. Based on dry weight, bioaccumulation potentials of these chemical substances were estimated with bioaccumulation factor (BAF) values greater than 2000 L/kg, suggestive of bioaccumulative in aquatic biota. Based on the concentrations measured, the daily intake (EDI) of parabens through fish consumption was estimated with the mean EDIs as 4.20, 2.41, and 1.93 ng/kg bw/day for toddlers, children, and adults in urban, respectively. This study provides baseline information about the occurrence and fate of parabens in the aquatic environment.

Environmental exposure to paraben and its association with blood pressure: A cross-sectional study in China

Parabens (PBs) are the most widely used preservatives. Recent epidemiological studies have indicated that environmental exposure to parabens has adverse health effects, such as increased metabolic diseases risk. However, limited information is available on the cardiovascular effect of paraben exposure. Hence, we conducted a cross-sectional study investigating the associations between exposure to parabens with high blood pressure risk and blood pressure levels among the general Chinese population. In this study, we enrolled 1405 individuals from a medical center in Wuhan, China. Urinary methylparaben (MeP), ethylparaben (EtP), propylparaben (PrP) and butylparaben (BuP) concentrations were determined. Multivariable logistic and linear regression models were applied to analyze the associations between urinary parabens and high blood pressure risk and blood pressure level changes. Bayesian kernel machine regression (BKMR) models were applied to estimate the combined effect of the four parabens. Compared with the first quartile group, participants with the fourth quartile of EtP, PrP, and ∑parabens (∑PBs) concentrations had a 2.10-fold (95% CI: 1.40, 3.00), 1.83-fold (95% CI: 1.27, 2.62) and 1.84-fold (95% CI: 1.27, 2.65) increased the risk of hypertension, respectively. High urinary EtP, PrP, and ∑PBs levels were found to increase the levels of systolic and diastolic blood pressure (SBP and DBP), mean arterial pressure (MAP), and mid-blood pressure (MBP). BKMR models indicated the overall effects of the paraben mixture were significantly associated with high blood pressure risk and blood pressure level changes. Furthermore, after stratification by sex, the associations of EtP exposure and blood pressure levels were more pronounced in males. Our results suggest that environmental exposure to parabens might elevate blood pressure levels and increase the risk of high blood pressure.

A pilot study of several environmental endocrine disrupting chemicals in children with autism spectrum disorder in south China

Autism spectrum disorders (ASD) is a group of heterogeneous neurodevelopmental disorders. Evidence has implied that environmental pollutants are important factors related to ASD. In this study, several environmental endocrine-disrupting chemicals, including parabens, benzophenone-type ultraviolet filters, hydroxyl polycyclic aromatic hydrocarbons, triclosan and tetrabromobisphenol A were analyzed in blood plasma in ASD children (n = 34) and the control children (n = 28). The results showed that parabens were the most concentrated chemicals (2.18 ng/mL, median value), followed by hydroxyl polycyclic aromatic hydrocarbons (0.73 ng/mL), benzophenone-type ultraviolet filters (0.14 ng/mL), triclosan (0.13 ng/mL) and tetrabromobisphenol A (0.03 ng/mL). ASD children accumulated significantly lower 2-hydroxy-4-methoxybenzophenone, 2,4-dihydroxybenzophenone, 4-hydroxybenzophenone and triclosan but higher 2-hydroxyphenanthrene and tetrabromobisphenol A than the control children (0.02/0.09 ng/mL of 2-hydroxy-4-methoxybenzophenone, p < 0.05; 0.04/0.07 ng/mL of 2,4-dihydroxybenzophenone, p < 0.05; 0.03/0.04 ng/mL of 4-hydroxybenzophenone, p < 0.05; 0.13/1.22 ng/mL of triclosan, p < 0.01; 0.03 ng/mL/not detected of 2-hydroxyphenanthrene, p < 0.05; 0.03/0.004 ng/mL of tetrabromobisphenol A, p < 0.05). Gender differences in certain environmental endocrine-disrupting chemicals were evident, and the differences were more inclined toward boys. Positive associations between 2-hydroxy-4-methoxybenzophenone and triclosan, and tetrabromobisphenol A and 2-hydroxyphenanthrene were found in ASD boys. Binary logistic regression analysis showed that the adjusted odds ratio value of 2-hydroxyphenanthrene in ASD boys was 11.0 (1.45-84.0, p < 0.05). This is the first pilot study on multiple environmental endocrine-disrupting chemicals in children with ASD in China.

Exposure to endocrine disrupters and cardiometabolic health effects in preschool children: Urinary parabens are associated with wider retinal venular vessels

BACKGROUND AND AIM

Parabens are widely used as antimicrobial preservatives in personal care products. Studies investigating obesogenic or cardiovascular effects of parabens show discordant results, while data on preschool children are lacking. Paraben exposure during early childhood could have profound cardiometabolic effects later in life.

METHODS

In this cross-sectional study paraben concentrations [methyl (MeP), ethyl (EtP), propyl (PrP), butyl (BuP)] were measured by ultra-performance liquid chromatography/tandem mass spectrometry in 300 urinary samples of 4-6-year-old children of the ENVIRONAGE birth cohort. Paraben values below the limit of quantitation (LOQ) were imputed by censored likelihood multiple imputation. The associations between log-transformed paraben values and cardiometabolic measurements (BMI z-scores, waist circumference, blood pressure and retinal microvasculature) were analyzed in multiple linear regression models with a priori selected covariates. Effect modification by sex was investigated by including interaction terms.

RESULTS

Geometric means (geometric SD) of urinary MeP, EtP, and PrP levels above the LOQ were 32.60 (6.64), 1.26 (3.45), and 4.82 (4.11) μg/L, respectively. For BuP more than 96% of all measurements were below the LOQ. Regarding the microvasculature, we found direct associations between MeP and central retinal venular equivalent (β = 1.23, p = 0.039) and PrP with the retinal tortuosity index (x103)(β = 1.75, p = 0.0044). Furthermore, we identified inverse associations between MeP and ∑parabens with BMI z-scores (β = -0.067, p = 0.015 and β = -0.070, p = 0.014 respectively), and EtP with mean arterial pressure (β = -0.69, p = 0.048). The direction of association between EtP and BMI z-scores showed evidence for sex-specific differences with a direct trend in boys (β = 0.10, p = 0.060).

CONCLUSIONS

Already at young age paraben exposure is associated with potentially adverse changes in the retinal microvasculature.

Association of parabens and bisphenols with lung function in children aged 5-12 years from Shanghai, China

Epidemiological studies have reported potential effects of individual paraben or bisphenol exposure on lung function, but few studies have estimated their joint effects. We conducted a cross sectional survey to investigate the associations of parabens and bisphenols exposure with lung function in 205 children aged 5-12 years from Shanghai, China. Urinary concentrations of six parabens [methyl-, ethyl-, propyl-, butyl-, benzyl-, and heptyl-paraben (MeP, EtP, PrP, BuP, BzP, and HeP)] and seven bisphenols [bisphenol A (BPA), bisphenol AF (BPAF), bisphenol AP (BPAP), bisphenol B (BPB), bisphenol P (BPP), bisphenol S (BPS), and bisphenol Z (BPZ)] were assessed by the high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Lung function, including forced expiratory volume in 1 s (FEV₁), forced vital capacity (FVC), FEV₁/FVC, peak expiratory flow (PEF), and forced expiratory flow between 25% and 75% of forced vital capacity (FEF_25-75%), was further measured. Linear regression, bayesian kernel machine regression (BKMR), and weighted quantile sum regression (WQS) evaluated the individual and joint relationships of the parabens and bisphenols with the lung function parameters. Further, the analysis was stratified by child sex. Parabens (MeP, EtP, PrP, and BuP) and bisphenols (BPA, BPAP, BPB, and BPS) with detection rates >75% were included for analyses. In linear regressions, parabens (MeP, PrP, and BuP) were generally negatively associated with FEV₁, FVC, PEF, and FEF_25-75%, but no associations for bisphenols were found. The association of parabens with lung function was more pronounced in girls. The aforementioned negative associations between parabens and lung function were confirmed by both the BKMR and WQS, with MeP being considered most heavily weighing chemical. Our findings suggested that exposure to parabens, either individuals or as a mixture, were associated with decreased lung function in children aged 5-12 years, and these associations were stronger among girls. Considering the cross-sectional study design, large longitudinal studies are warranted to confirm our findings.

Paraben exposure through drugs in the neonatal intensive care unit: a regional cohort study

Background and objectives: Environmental factors influence the development of very preterm infants (VPIs, born at less than 32 weeks of gestation). It is important to identify all potential sources of paraben exposure in these vulnerable infants. We aimed to quantify paraben exposure via drug administration in a cohort of VPI cared for in neonatal intensive care units (NICUs). Methods: A prospective, observational study was carried out over a five-year period in a regional setting (two NICUs using the same computerized order-entry system). The main outcome was exposure to paraben-containing drugs. The secondary outcomes were: time of the first exposure, daily intake, number of infants exceeding paraben acceptable daily intake (ADI: 0-10 mg/kg/d), duration of exposure, and cumulative dose. Results: The cohort consisted of 1,315 VPIs [BW 1129.9 (±360.4) g]. Among them, 85.5% were exposed to paraben-containing drugs. In 40.4% of infants, the first exposure occurred during the second week of life. Mean paraben intake and duration of exposure were, respectively, 2.2 (±1.4) mg/kg/d and 33.1 (±22.3) days. The cumulative paraben intake was 80.3 (±84.6) mg/kg. The ADI was exceeded in 3.5% of exposed infants. Lower GA was associated with higher intake and longer exposure (p < 0.0001). The main molecules involved in paraben exposure were: sodium iron feredetate, paracetamol, furosemide, and sodium bicarbonate + sodium alginate. Conclusion: Commonly used drugs are potential source of parabens, and ADI can be easily exceeded in VPIs cared for in NICUs. Efforts are needed to identify paraben-free alternative formulations for these vulnerable infants.

Presence of Parabens in Different Children Biological Matrices and Its Relationship with Body Mass Index

Parabens have been accepted almost worldwide as preservatives by the cosmetic, food, and pharmaceutical industries. Since epidemiological evidence of the obesogenic activity of parabens is weak, the aim of this study was to investigate the association between parabens exposure and childhood obesity. Four parabens (methylparaben/MetPB, ethylparaben/EthPB, propylparaben/PropPB, and butylparaben/ButPB) were measured in 160 children's bodies between 6 and 12 years of age. Parabens measurements were performed with ultrahigh-performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS). Logistic regression was used to evaluate risk factors for elevated body weight associated with paraben exposure. No significant relation was detected between children's body weight and the presence of parabens in the samples. This study confirmed the omnipresence of parabens in children's bodies. Our results could be a basis for future research about the effect of parabens on childhood body weight using nails as a biomarker due to the ease of its collection and its non-invasive character.

Within-day variability, predictors, and risk assessments of exposure to parabens among Chinese adult men

BACKGROUND

Parabens, as suspected endocrine disruptors, are widely used in personal care products and pharmaceuticals. However, variability, predictors, and risk assessments of human exposure to parabens are not well characterized.

OBJECTIVE

To evaluate within-day variability, predictors, and risk assessments of exposure to parabens among Chinese adult men.

METHODS

We measured four parabens including methylparaben (MeP), ethylparaben (EtP), propylparaben (PrP), and butylparaben (BuP) in repeated urine samples from 850 Chinese adult men. We examined the variability by intraclass correlation coefficients (ICCs) and identified the predictors by multivariable linear mixed models. We assessed risks of paraben exposures based on the estimated daily intake (EDI).

RESULTS

The four parabens were detected in >76% of urinary samples. We observed fair to good to high reproducibility (ICCs: 0.71 to 0.86) for urinary paraben concentrations within one day. Use of facial cleanser was associated with higher four urinary paraben concentrations. Increasing age, taking medicine, intravenous injection, and interior decoration in the workplace were related to higher urinary concentrations of specific parabens. Smoking and drinking were associated with lower urinary concentrations of specific parabens. The maximum EDIs for the four parabens ranged from 13.76 to 848.68 μg/kg bw/day, and 0.9% of participants had the hazard quotient values > 1 driven by PrP exposure.

CONCLUSIONS

Urinary paraben concentrations were less variable within one day. Several lifestyle characteristics including use of facial cleanser and pharmaceuticals may contribute to paraben exposures.

Occurrence and profile characteristics of environmental phenols in human urine from a rural area in Northwestern China

Many environmental phenols, such as bisphenols, benzophenones and parabens, are known as endocrine disruptors and can adversely affect human health. However, the knowledge of human exposure to common environmental phenols in Chinese rural areas is insufficient. In this context, 181 urine samples were collected from participants in a rural area in Northwest China and were analyzed for nine bisphenols, three benzophenones and four parabens. Bisphenol A (BPA), bisphenol S, benzophenone-1 (BP-1), benzophenone-3 (BP-3), 4-hydroxybenzophenone, methylparaben (MeP), ethylparaben and propylparaben (PrP) were detected in more than 50% of the urine samples, with median concentrations of 0.938 ng/mL, 0.0111 ng/mL, 0.191 ng/mL, 1.30 ng/mL, 0.0320 ng/mL, 25.9 ng/mL, 4.31 ng/mL and 1.94 ng/mL, respectively. A significant positive correlation was observed between BP-1 and BP-3, as well as between MeP and PrP, indicating metabolic transformation and combined use, respectively. The concentrations of MeP and PrP in females were significantly higher than those in males, suggesting that females were exposed to more MeP and PrP than males. Urinary concentrations of BPA, BP-3, MeP and PrP could be influenced by age. Other demographic information, such as annual household income, education and occupation was not associated with the exposure level of the targeted phenols in adults. The estimated daily intakes of the analytes except BPA were all below their respective tolerable/acceptable daily intake levels. This study profiles the demographic differences in the exposure to environmental phenols in general populations from rural areas and provides information on risk assessments.

Impact of Paraben Exposure on Adiposity-Related Measures: An Updated Literature Review of Population-Based Studies

Parabens are alkyl esters of p-hydroxybenzoic acid that are commonly used in pharmaceutical and cosmetic products. Humans are exposed to parabens when they use these products and through diet. There are growing concerns that paraben exposure can adversely impact human health. The endocrine-disrupting and obesogenic properties of parabens have been observed in animal studies and in vitro, prompting the increase in population-based studies of paraben exposure and adiposity-related endpoints. In this review, we summarize epidemiological studies published between 2017 and 2022 that examined paraben exposure in utero, between birth and adolescence, and in adulthood, in relation to adiposity-related measures. Overall, these studies provide some evidence that suggests that paraben exposure, especially during critical development windows, is associated with adiposity-related measures. However, we have noted several limitations in these studies, including the predominance of cross-sectional studies, inconsistent sample collection procedures, and small sample sizes, which should be addressed in future studies.

Estimated daily intake of phthalates, parabens, and bisphenol A in hospitalised very low birth weight infants

Very low birth weight infants (VLBW, birth weight (BW) < 1500 g) are exposed to phthalates, parabens and bisphenol A (BPA) early in life. We estimated daily intake (EDI) of these excipients in 40 VLBW infants the first and fifth week of life while hospitalised. Based on urinary samples collected in 2010, EDI was calculated and compared to the tolerable daily intake (TDI) with hazard quotients (HQs) evaluated. A HQ > 1 indicates that EDI exceeded TDI with increased risk of adverse health effects. EDI was higher in VLBW infants compared to term-born infants and older children. VLBW infants born at earlier gestational age (GA), or with lower BW, had higher EDI than infants born at later GA or with higher BW. First week median EDI for BPA was higher than TDI in 100% of infants, in 75% for di(2-ethylhexyl) phthalate (DEHP), 90% for the sum of butyl benzyl phthalate (BBzP), di-n-butyl phthalate (DnBP), DEHP and di-iso-nonyl phthalate (DiNP) = ∑BBzP+DnBP+DEHP+DiNP, and in 50% of infants for propylparaben (PrPa), indicating increased risk of adverse effects. Fifth week EDI remained higher than TDI in all infants for BPA, in 75% for DEHP and ∑BBzP+DnBP+DEHP+DiNP, and 25% of infants for PrPa, indicating prolonged risk. Maximum EDI for di-iso-butyl phthalate was higher than TDI suggesting risk of adverse effects at maximum exposure. VLBW infants born earlier than 28 weeks GA had higher EDI, above TDI, for PrPa compared to infants born later than 28 weeks GA. Infants with late-onset septicaemia (LOS) had higher EDI for DEHP, ∑BBzP+DnBP+DEHP+DiNP and BPA, above TDI, compared to infants without LOS. More 75% of the infants' EDI for DEHP and ∑BBzP+DnBP+DEHP+DiNP, 25% for PrPa, and 100% of infants' EDI for BPA, were above TDI resulting in HQs > 1, indicating increased risk of adverse health effects.

Association of As, Pb, Cr, and Zn urinary heavy metals levels with predictive indicators of cardiovascular disease and obesity in children and adolescents

BACKGROUND

Although the basic causes of obesity and cardiovascular illness have been extensively researched, little is known about the influence of environmental variables such as heavy metals on obesity development and cardiovascular disease in children and adolescents. The assumption that arsenic (As), lead (Pb), chromium (Cr), and zinc (Zn) exposure impact obesity and predictors of cardiovascular disease was explored in this study.

METHOD

A questionnaire was used to gather demographic information as well as certain determinants of exposure to As, Pb, Cr, and Zn from 106 children and adolescents aged 6 to 18. Physical tests (height, weight, waist circumference (WC), BMI, BMI Z-score, Systolic blood pressure (SBP), Diastolic blood pressure (DBP)), blood samples for clinical trials (Fasting Blood Sugar (FBS), Total Cholesterol (TC), Triglyceride (TG), Low-Density Lipoprotein (LDL), High-Density Lipoprotein (HDL) (, and urine samples for urinary creatinine measurement and measures of As, Pb, Cr, and Zn in urine were obtained using the Inductively coupled plasma mass spectrometry (ICP/MS).

RESULTS

The average age of the participants in the research was 11.42 ± 3.68. The majority of the participants in the research were boys (56 people). As, Pb, and Zn mean concentrations (μg/L) were greater in obese adults (42.60 ± 22.59, 20.63 ± 14.64, 326 ± 164.82), respectively. After adjusting for possible confounding factors, the data revealed that adolescents aged 12-18 years had higher levels of As and Pb (8.69 and 5.02 μg/L) than children aged 6 to 11. As and Zn metals had significant association with FBS and lipid profile (TC, TG, LDL, HDL), lead had significant correlations with lipid profile, while Cr had significant correlations with WC, SBP, FBS, LDL, TC.

CONCLUSION

Childhood and adolescent exposure to As, Pb, Cr, and Zn can impact obesity and cardiovascular disease markers. The current research was a cross-sectional study, which necessitates group studies and case studies to evaluate causal relationships.

Increased Prevalence of Atopic Dermatitis in Children Aged 0-3 Years Highly Exposed to Parabens

The prevalence of allergic diseases, such as bronchial asthma, atopic dermatitis, nasal allergies (pollinosis), and food allergies, has been increasing in many countries. The hygiene hypothesis was recently considered from the perspective of exposure to antimicrobial agents and preservatives, such as parabens (CAS number, 94-13-3). It currently remains unclear whether parabens, which are included in many daily consumer products such as cosmetics, shampoos, and personal care products as preservative antimicrobial agents, induce or aggravate allergies. Therefore, the aim of the present study was to examine the relationship between exposure to parabens and the prevalence of allergic diseases in Japanese children. The cross-sectional epidemiology of 236 children aged 0-3 years who underwent health examinations in Shika town in Japan assessed individual exposure to parabens using urinary concentrations of parabens. The results obtained showed that the prevalence of atopic dermatitis was significantly higher in children with high urinary concentrations of parabens than in those with low concentrations (p < 0.001). This relationship remained significant after adjustments for confounding factors, such as age, sex, Kaup's index, and passive smoking (p < 0.001). In conclusion, the present results from a population study suggested a relationship between atopic dermatitis and exposure to parabens. A longitudinal study using a larger sample number and a detailed examination of atopic dermatitis, including EASI scores and exposure to parabens, will be necessary.

Dietary exposure to parabens and body mass index in an adolescent Spanish population

Parabens are alkyl esters of p-hydroxybenzoic acid which are extensively used in cosmetics, pharmaceuticals and foodstuffs due to their antimicrobial properties. The most commonly used parabens are methyl-(MeP), ethyl-(EtP), propyl-(PrP) and butyl-(BuP) paraben. Most human exposure to parabens is achieved through the consumption of food or pharmaceutical products and the use of personal care products. However, studies on dietary parabens exposure and the associated factors are very scarce. The main aim of the present study was to explore factors associated with dietary exposure to parabens in Spanish adolescents according to gender. Dietary data and anthropometric measures were collected from 585 adolescents (53.4% boys) aged 12-16 years. Parabens exposure through diet was assessed using a food frequency questionnaire with food products providing more than 95% of energy and macronutrient intake being included in analysis. Stepwise regression was used to identify the foods that most contributed to parabens intake. Logistic regression was used to evaluate factors predicting higher dietary exposure to parabens. The main contributors to dietary MeP, EtP, PrP and BuP exposure in adolescent boys were eggs (41.9%), canned tuna (46.4%), bakery and baked goods products (57.3%) and pineapple (61.1%). In adolescent girls, the main contributors were apples and pears (35.3%), canned tuna (42.1%), bakery and baked goods products (55.1%) and olives (62.1%). Overweight/obese girls were more likely to belong to the highest tertile of overall parabens intake (odds ratio [OR]: 3.32; 95% confidence interval [95% CI]: 1.21-9.15) and MeP (OR: 3.05; 95% CI: 1.14-8.12) than those with a body mass index lower than 25 kg/m². These findings suggest a positive association between dietary exposure to parabens and overweight/obesity in adolescent girls.

Paraben Compounds—Part I: An Overview of Their Characteristics, Detection, and Impacts

Parabens are widely used in different industries as preservatives and antimicrobial compounds. The evolution of analytical techniques allowed the detection of these compounds in different sources at µg/L and ng/L. Until today, parabens were already found in water sources, air, soil and even in human tissues. The impact of parabens in humans, animals and in ecosystems are a matter of discussion within the scientific community, but it is proven that parabens can act as endocrine disruptors, and some reports suggest that they are carcinogenic compounds. The presence of parabens in ecosystems is mainly related to wastewater discharges. This work gives an overview about the paraben problem, starting with their characteristics and applications. Moreover, the dangers related to their usage were addressed through the evaluation of toxicological studies over different species as well as of humans. Considering this, paraben detection in different water sources, wastewater treatment plants, humans and animals was analyzed based on literature results. A review of European legislation regarding parabens was also performed, presenting some considerations for the use of parabens.

Obesity and endocrine-disrupting chemicals

Obesity is now a worldwide pandemic. The usual explanation given for the prevalence of obesity is that it results from consumption of a calorie dense diet coupled with physical inactivity. However, this model inadequately explains rising obesity in adults and in children over the past few decades, indicating that other factors must be important contributors. An endocrine-disrupting chemical (EDC) is an exogenous chemical, or mixture that interferes with any aspect of hormone action. EDCs have become pervasive in our environment, allowing humans to be exposed daily through ingestion, inhalation, and direct dermal contact. Exposure to EDCs has been causally linked with obesity in model organisms and associated with obesity occurrence in humans. Obesogens promote adipogenesis and obesity, in vivo, by a variety of mechanisms. The environmental obesogen model holds that exposure to obesogens elicits a predisposition to obesity and that such exposures may be an important yet overlooked factor in the obesity pandemic. Effects produced by EDCs and obesogen exposure may be passed to subsequent, unexposed generations. This "generational toxicology" is not currently factored into risk assessment by regulators but may be another important factor in the obesity pandemic as well as in the worldwide increases in the incidence of noncommunicable diseases that plague populations everywhere. This review addresses the current evidence on how obesogens affect body mass, discusses long-known chemicals that have been more recently identified as obesogens, and how the accumulated knowledge can help identify EDCs hazards.

Associations of urinary concentrations of phthalate metabolites, bisphenol A, and parabens with obesity and diabetes mellitus in a Korean adult population: Korean National Environmental Health Survey (KoNEHS) 2015-2017

Phthalates and bisphenol A (BPA) have been suspected as risk factors for obesity and diabetes mellitus (DM) among humans. However, associations between phthalates and environmental phenols are often inconsistent across different populations. In this study, we recruited the adult population (n = 3782) of the Korean National Environmental Health Survey (KoNEHS) 2015-2017 (Cycle 3) and assessed the associations between urinary biomarkers of phthalate, BPA, and paraben exposure with obesity and DM. A potential collider issue with the use of urinary creatinine (Cr) or specific gravity (SG) exists when adjusting urinary dilution; therefore, a covariate-adjusted standardization (CAS) was employed for adjustment, and the results were compared. In the present population, the direction of the association often varied depending on the choices made to adjust urinary dilution. When using CAS, the direction of association resembled those of previously reported experimental observations. With Cr or SG adjustment, ORs for obesity decreased in the highest quartiles of monocarboxyoctyl phthalate (MCOP) [OR (95% CI) = Cr: 0.71 (0.54, 0.93); SG: 0.68 (0.52, 0.90)], monocarboxy-isononyl phthalate (MCNP) [OR (95% CI) = Cr: 0.67 (0.52, 0.87); SG: 0.68 (0.52, 0.89)], and mono(3-carboxylpropyl) phthalate (MCPP) in the urine [OR (95% CI) = Cr: 0.60 (0.47, 0.76); SG: 0.61 (0.48, 0.77)]; however, with CAS, these negative associations disappeared. Instead, mono-benzyl phthalate (MBzP) [OR (95% CI) = 1.31 (1.03, 1.66)], BPA [OR (95% CI) = 1.62 (1.27, 2.06)], or ethyl paraben (EtP) [OR (95% CI) = 1.51 (1.19, 1.91)] concentrations in the highest quartile showed positive associations with a higher risk of obesity. On the other hand, for DM, an overall decrease in ORs was observed for phthalate metabolites and BPA following SG adjustment and disappeared with CAS adjustment. In addition, the highest quartiles of BPA, methyl paraben (MeP), and ethyl paraben (EtP) showed a significantly higher risk of DM than those in the lowest quartiles following CAS [OR (95% CI) = BPA: 1.65 (1.06, 2.59); MeP: 1.68 (1.08, 2.60); and EtP: 2.74 (1.77, 4.24), respectively]. The present observations outline the importance of using an appropriate adjustment method for urinary dilution in association studies on obesity and DM. In addition, several phthalates, BPA, and parabens were identified as potential chemical risk factors for these outcomes. Further studies are warranted in other populations to confirm these observations.

Endocrine-Disrupting Chemicals' (EDCs) Effects on Tumour Microenvironment and Cancer Progression: Emerging Contribution of RACK1

Endocrine disruptors (EDCs) can display estrogenic and androgenic effects, and their exposure has been linked to increased cancer risk. EDCs have been shown to directly affect cancer cell regulation and progression, but their influence on tumour microenvironment is still not completely elucidated. In this context, the signalling hub protein RACK1 (Receptor for Activated C Kinase 1) could represent a nexus between cancer and the immune system due to its roles in cancer progression and innate immune activation. Since RACK1 is a relevant EDCs target that responds to steroid-active compounds, it could be considered a molecular bridge between the endocrine-regulated tumour microenvironment and the innate immune system. We provide an analysis of immunomodulatory and cancer-promoting effects of different EDCs in shaping tumour microenvironment, with a final focus on the scaffold protein RACK1 as a pivotal molecular player due to its dual role in immune and cancer contexts.

Identification of novel paraben-binding peptides using phage display

Parabens are alkyl esters of 4-hydroxybenzoic acid, which is derived from a family of synthetic esters of p-hydroxybenzoic acid. Among all the kinds of paraben, two parabens (methyl paraben, MP; and n-propyl paraben, PP) are the most generally used as preservatives in personal care products, such as cosmetics, pharmaceuticals, and food also, and are often presented together. However, a number of studies have reported that the toxicity of parabens affects the water environment, and human as well. This study utilized M13 phage display technology to provide easy, efficient, and relatively inexpensive methods to identify peptides that bind to MP and PP, respectively, to remove in wastewater. At first, biopanning was performed, to sort MP and PP specific binding phages, and three cases of experiment, including negative control (NC), which could sort unspecific binding phage, were conducted at the same time. Phage binding affinity tests were substituted by concentration reduction using antibody conjugated magnetic beads, and paraben concentration was measured by HPLC. Analysis showed that the MP concentration reduction of 38% was the highest in M4 phage, while the PP concentration reduction of 44% was the highest in P3 phage. We successfully screened two peptides specific to MP and PP, namely, MP4 and PP3, respectively; the results showed that the MP concentration reduction in MP4 was the highest at 44%, and the PP concentration reduction in PP3 was the highest at 39%, and their specificity was measured by the capture rate between target and control. In conclusion, the phage display technique shows applicability to the removal of parabens in water; furthermore, it also shows the possibility of the detection or removal of other chemicals.

Multispecies bioassay of propylparaben to derive protective concentrations for soil ecosystems using a species sensitivity distribution approach

Propylparaben is widely used as a preservative in pharmaceuticals and personal care products and is ultimately excreted by the human body. Thus, propylparaben reaches sewage and enters the soil environment by sludge fertilization and wastewater irrigation. However, there are few existing studies on the toxicity and risks of such chemicals in terrestrial environments. In this study, a multispecies bioassay for propylparaben was performed and protective concentrations (PCs) were derived based on toxicity values by probabilistic ecological risk assessment. Acute and chronic bioassays were conducted on 11 species in eight taxonomic groups (Magnoliopsida, Liliopsida, Clitellata, Entognatha, Entomobryomorpha, Chromadorea, Chlorophyceae, Trebouxiophyceae). Based on the toxicity values calculated, the PC₉₅ values for acute and chronic SSDs were 13 and 6 mg/kg dry soil, respectively. Toxicity varied among taxa, with soil algae emerging as the most sensitive to propylparaben. This may be attributable to differences in exposure pathways among species. The exposure pathway of propylparaben can be altered by adsorption to soil particles. As parabens are presently under-regulated globally in terms of their environmental effects, our findings can serve as the basis to propose standard values for environmental protection.

Effects of prenatal exposure to five parabens on neonatal thyroid function and birth weight: Evidence from SMBCS study

BACKGROUND

Parabens, suspected as endocrine-disrupting chemicals, are nearly ubiquitous in the human body and exposure to these chemicals during pregnancy may disrupt thyroid hormones homeostasis and even affect fetal growth, although the impacts are still unclear.

OBJECTIVES

We aimed to estimate associations of maternal urinary paraben concentrations with cord serum thyroid hormones and birth weight.

METHODS

A subset of 437 mother-newborn pairs were included from a prospective birth cohort with five parabens quantified in maternal urine and seven thyroid function indicators measured in cord serum samples. Multivariable linear regression models and elastic net regression (ENR) models were applied to explore associations between individual and mixtures of prenatal urinary paraben concentrations and thyroid hormones and birth weight, respectively.

RESULTS

Maternal urinary ethyl-paraben (EtP) concentrations were associated with increased cord serum total triiodothyronine levels (TT3) [percent change: 1.51%; 95% confidence interval (CI): 0.20%, 2.74%; p=0.017]. Urinary propyl-paraben (PrP) levels predicted higher thyroid peroxidase antibodies (percent change: 4.19%, 95%CI: 0.20%, 8.44%; p=0.041). Maternal urinary EtP and butyl-paraben (BuP) concentrations were significantly positively associated with birth weight [regression coefficient, (β)=40.9g, 95%CI: 3.99, 76.6; p=0.030; β=62.1g, 95%CI: 8.70, 115; p=0.023, for EtP and BuP, respectively]. In sex-stratified analyses, positive relationship between EtP levels and birth weight was observed in boys. Urinary EtP concentrations predicted higher TT3 levels in cord serum samples, assessing parabens as a chemical mixture with ENR models.

CONCLUSIONS

Prenatal exposure to parabens may affect thyroid hormone indicators with increased serum TT3 levels and associate with higher birth weight, especially in boys. The underlying biological mechanisms and effects of prenatal paraben exposures on disruption of thyroid function homeostasis and potential impacts of childhood growth and development needed to be further investigated.

A Novel HPLC Method for Simultaneous Determination of Methyl, Ethyl, n-propyl, Isopropyl, n-butyl, Isobutyl and Benzyl Paraben in Pharmaceuticals and Cosmetics

INTRODUCTION

The alkyl esters of p-hydroxybenzoic acid at the C-4 position, "the parabens," including methyl, ethyl, propyl, and butyl, are widely used as antimicrobial preservatives in foods, cosmetics, and pharmaceuticals. Official regulations on the use of these compounds make their analysis essential for the estimation of their exposure.

METHODS

On this basis, the presented study was realized to develop a simple, selective and cheap high-performance liquid chromatographic method for the quantitative determination of methylparaben, ethylparaben (EP), n-propyl paraben (NPP), isopropyl paraben (IPP), n-butyl paraben (NBP), isobutyl paraben (IBP) and benzyl paraben (BP) in pharmaceuticals and cosmetic products.

RESULTS

The chromatographic separation of the analytes was achieved under flow rate gradient elution conditions using a C18-bonded core-shell silica particle column (2.6 μm particle size, 150 × 3.0 mm from Phenomenex Co.). The samples were injected into the system as aliquots of 1.0 μL, and the compounds were detected by using a photodiode array detector set at 254 nm wavelength. With this technique, seven paraben derivatives can be determined in the concentration range of 250-2000 ng/mL. The recovery of the method is in the range of 99.95-13.84%, and the RSD is at a maximum value of 3.95%.

CONCLUSION

The proposed method was fully validated and successfully applied to different pharmaceutical and cosmetic samples (n=16), including syrups, suspensions, oral sprays, gels, etc. At least one paraben derivative was detected in six samples and was determined quantitatively. The maximum amount of a paraben derivative found in the analyzed samples was 321.7 ng/mL, which was MP. To the best of our knowledge, this is the first LC method, which is applicable both on pharmaceutical and cosmetic samples.

Amended Safety Assessment of Parabens as Used in Cosmetics

The Expert Panel for Cosmetic Ingredient Safety (Panel) assessed the safety of 21 parabens as preservatives in cosmetic products. All of these ingredients are reported to function in cosmetics as preservatives; however, 5 are reported to also function as fragrance ingredients. The Panel reviewed relevant data relating to the safety of these ingredients under the reported conditions of use in cosmetic formulations. The Panel concluded that 20 of the 21 parabens included in this report are safe in cosmetics in the present practices of use and concentration described in this safety assessment when the sum of the total parabens in any given formulation does not exceed 0.8%. However, the available data are insufficient to support a conclusion of safety for benzylparaben in cosmetics.

Urinary bisphenol A concentrations and adiposity measures at age 7 years in a prospective birth cohort

Bisphenol A (BPA) exposure during early life may increase risk of childhood obesity, however, prospective evidence of birth cohort is limited and inconclusive. We aimed to explore the associations of maternal and childhood BPA exposure with child adiposity measures, including body mass index, waist circumference and skinfold thickness and waist to height ratio of children at 7 years. 430 mother-child pairs were examined from a population-based prospective cohort in a rural area of East China. BPA concentrations of spot urine samples were quantified in mothers and their children aged 3 and 7 years. Maternal urinary BPA concentration was significantly positively associated with waist circumference in children aged 7 years (β = 0.508 cm, 95% CI: 0.067, 0.950). These significant associations were not modified by child sex, but they were only observed among girls in sex-stratified analyses. Risk of central obesity related to prenatal BPA exposure was significantly higher in the second and the third tertile than those in the first tertile (odds ratio, OR = 2.510, 95% CI = 1.146, 5.499; OR = 2.584, 95% CI = 1.186, 5.631, respectively; p for trend = 0.022). The present findings suggested that prenatal exposure to BPA may enhance waist circumference of children and thereby increase risk of central obesity in school-age girls.

Clinical epidemiology studies on potential effects of endocrine disrupting chemicals (EDCs) should exclude subjects with obesity as determined by BMI

Obesity as determined by BMI is a confounder in clinical evaluations of the effects of endocrine disrupting chemicals (EDCs). Validated regulatory tests are used to determine whether a chemical acts via a mode of action (MOA) that affects estrogen, androgen, thyroid or steroidogenic pathways. Test batteries for evaluating EDCs include QSAR, in vitro assays, and animal testing. Studies suggest that EDCs pose the greatest risk during prenatal and early infant development when organ systems are developing. Health effects include lowered fertility, endometriosis, and cancers associated with estrogenic activity. Epidemiology studies on adverse effects of EDCs in the general population are difficult to conduct due to very low exposures of EDCs in non-occupational cohorts, and lack of exposure measurements between cases and controls. In contrast with very low levels of hormonal perturbation from nano-molar to micro-molar exposures to EDCs, adipose tissue in obesity alters estrogen, testosterone, thyroid stimulating hormone, and inflammation levels. Obesity in pregnancy and gestational diabetes are associated with adverse outcomes in infants and children including autism, poor motor skills, lowered IQ, and altered birth weight. Neonatal effects of obesity are confounded by average lower socio-economic status. The already perturbed endocrine balance in overweight or obese persons renders them particularly worthy subjects for clinical epidemiology investigations on the possible effects of endocrine disrupting chemicals. However, inclusion of subjects with obesity requires accounting for potentially confounding effects of the hormonal influences arising from excess adiposity. If subjects with obesity are to be included in clinical epidemiological evaluations related to hormonal effects, the subjects should be classified by body fat percentage rather than by the much less exact measure of body mass index (BMI).

Exposure to endocrine-disrupting chemicals and anthropometric measures of obesity: a systematic review and meta-analysis

OBJECTIVE

Endocrine-disrupting chemicals (EDCs) are viewed as a major potential link between the environment and obesity development. We did a systematic review and meta-analysis to examine the association between exposure to EDCs and obesity.

DATA SOURCES, DESIGN AND ELIGIBILITY CRITERIA

PubMed, Scopus and Web of Science were searched from inception to 6 June 2018 for studies primarily addressing the association between exposure to EDCs after the age of 2 years and anthropometric measures of obesity or body fat. The Newcastle-Ottawa scale was used to assess the risk of bias.

DATA EXTRACTION AND SYNTHESIS

Two independent reviewers screened and conducted data extraction and synthesis. A third reviewer resolved disagreements.

RESULTS

A total of 73 studies investigating bisphenol A (32 286 individuals), organochlorine compounds (34 567 individuals), phthalates (21 401 individuals), polybrominated biphenyls (2937 individuals), polycyclic aromatic hydrocarbons (5174 individuals), parabens (4097 individuals), benzoic acid (3671 individuals) and polyfluoroalkyl substances (349 individuals) met our inclusion criteria. Most had a cross-sectional design and low or medium risk of bias. In qualitative analysis, bisphenol A and phthalates were consistently associated with general and abdominal obesity, in children and adults, and some studies suggested this association was age-dependent and gender-dependent. Meta-analysis indicated a significant association between exposure to bisphenol A and overweight (OR 1.254, 95% CI 1.005 to 1.564), obesity (OR 1.503, 95% CI 1.273 to 1.774) and increased waist circumference (OR 1.503, 95% CI 1.267 to 1.783) in adults, and between exposure to 2,5-dichlorophenol and obesity in children (OR 1.8, 95% CI 1.1018 to 3.184).

CONCLUSION

Most observational studies supported a positive association between obesity and exposure to EDCs. Although causality cannot be determined from these data, they underscore the need to limit human exposure to EDCs in light of the evidence from animal and cell-based studies indicating the effects of these chemicals on adiposity.

PROSPERO REGISTRATION NUMBER

CRD42018074548.

Biomonitoring of bisphenols A, F, S and parabens in urine of breastfeeding mothers: Exposure and risk assessment

In the present study we used human biomonitoring to assess the internal exposure and the risk to four parabens and three bisphenols in 103 Spanish breastfeeding mothers participating in the BETTERMIILK project. Urinary methylparaben (MP), ethylparaben (EP), propylparaben (PP) and butylparaben (BP) presented detection frequencies ranging from 12% (BP) to 92% (MP), while bisphenol A (BPA), bisphenol F (BPF) and bisphenol S (BPS) were detected in 76% (BPA) and 20% (BPF, BPS) of the mothers. Average paraben concentrations (geometric mean) ranged from 0.021 ng mL^-1 (BP) to 17.7 ng mL^-1 (MP), whereas bisphenols had geometric means concentrations from 0.042 ng mL^-1 (BPF) to 0.927 ng mL^-1 (BPA). Except for BPA, the estimated daily intakes (EDI) were calculated in order to interpret urinary levels in a risk assessment context. The obtained EDIs ranged from 0.00042 mg/kg/day for PP to 0.0434 mg/kg/day for MP and EP. A hazard quotient (HQ) was calculated for BPA (0.0049) and parabens (0.001-0.004), showing no risk in the studied population. Sociodemographic characteristics, food consumption, and usage patterns of personal care products (PCPs) were investigated as possible determinants of exposure. Use of makeup and skincare products were associated with higher concentrations of MP and PP, respectively. Regarding dietary habits, MP was also associated with the consumption of packaged and bakery products.

Exposure to parabens and prevalence of obesity and metabolic syndrome: An analysis of the Canadian Health Measures Survey

BACKGROUND

Parabens are group of widely used preservative agents in the cosmetic, food, and pharmaceutical industries. They are estrogenic and anti-androgenic, and thus have the potential to alter the hormonal regulation of energy metabolism, and in turn affect obesity and metabolic health. Compared to obesity alone, having metabolic syndrome (a cluster of cardiometabolic risk factors) further increases the risk of cardiovascular disease, diabetes, and certain cancers. We examined whether exposure to parabens was associated with obesity, metabolic syndrome or its components among Canadians.

METHODS

Methyl, ethyl, propyl, and butyl paraben concentrations were measured in the urine of 2,564 individuals participating in Cycle 4 (2014-2015) of the Canadian Health Measures Survey, a national biomonitoring survey. We assessed associations between specific gravity-corrected log10-transformed paraben concentrations and obesity, metabolic syndrome and its components (waist circumference, HDL cholesterol, triglycerides, fasting blood glucose and blood pressure) via Poisson regression with robust variance estimators for binary outcomes and via linear regression for outcomes expressed continuously. We stratified analyses by age (children aged 3 to 17 years vs. adults aged 18 years and older) and investigated the presence of effect modification by sex.

RESULTS

A 10-fold increase in propyl paraben concentration was associated with a 40% (95% CI: 3, 90) higher prevalence of metabolic syndrome among men, while ethyl paraben was associated with a 63% (95% CI: 2, 86) lower prevalence among women. Among women, methyl paraben was inversely associated with obesity, and methyl, propyl and ethyl parabens were associated with higher high density lipoprotein (HDL) cholesterol. No associations were observed among children.

CONCLUSIONS

This is the first study to report a positive association between parabens and metabolic syndrome in men. Protective associations among women previously reported for obesity were also observed for metabolic syndrome and HDL cholesterol. These results should be confirmed in longitudinal studies.

The Beast of Beauty: Environmental and Health Concerns of Toxic Components in Cosmetics

Cosmetic products are used in large quantities across the world. An increasing number of chemical compounds are being added to the formulation of cosmetic products as additives, fragrances, preservatives, stabilizers, surfactants, dye and shine to potentiate their quality, property and shelf life. Owing to their widespread use, active residues of cosmetic products are continuously introduced into the environment in several ways. Many of these chemicals are bioactive and are characterized by potential bioaccumulation ability and environmental persistence, thus exerting a major risk to humans and the health of ecosystems. Hence, the indiscriminate consumption of cosmetics may present a looming issue with significant adverse impacts on public health. This review intends to spotlight a current overview of toxic ingredients used in formulating cosmetics such as parabens, triclosan, benzalkonium chloride, 1,4-dioxane, plastic microbeads, formaldehyde, diazolidinyl urea, imidazolidinyl urea, sunscreen elements (organic and inorganic UV filters) and trace metals. Specific focus is given to illustrate the biological risks of these substances on human health and aquatic system in terms of genotoxicity, cytotoxicity, neurotoxicity mutagenicity, and estrogenicity. In addition to conclusive remarks, future directions are also suggested.

Urinary parabens in children from South China: Implications for human exposure and health risks

Parabens are extensively applied in cosmetics, drugs or food as preservatives and have become common pollutants in environmental media. However, data on human exposure to these chemicals is still limited, especially for children. This study aimed to investigate parabens in urine samples of children and to evaluate the cumulative risk of paraben exposure. Five short-chain parabens were measured in 255 urine samples collected from children in a kindergarten and elementary schools from South China. Methyl paraben (MeP), ethyl paraben (EtP) and n-propyl paraben (PrP) were widely detected in urine samples (detection rates > 94.9%), indicating their widespread exposure. The urinary median concentrations of MeP, EtP and PrP were 2.25, 0.33 and 0.50 μg/L, respectively. Significantly positive correlations (p < 0.01) were observed between MeP and PrP in urine, suggesting similar sources and/or metabolic pathways of these two chemicals. The median estimated daily intakes (EDIs) of parabens were determined to be 18.1 and 9.79 μg/kg-bw/day for kindergarten children and elementary school students, respectively. Estimation of human intake and exposure risks indicated potential risks of PrP exposure for elementary school students. This is the first study addressing paraben exposure in South China children.

Investigating exposure to endocrine disruptors via hair analysis of pregnant women

The aim of this study was the monitoring of the levels of parabens (PBs) and triclosan (TCS) in head hair samples of women collected during the first months of their pregnancy. Personal details concerning somatometric and demographic characteristics, dietary habits, use of personal care products and the medical and obstetrical history of the pregnant women as well as infants' somatometric characteristics and health condition were recorded through relevant questionnaires. Ninety five hair samples were collected, extracted by solid-liquid extraction and analysed using a liquid chromatography-mass spectrometry system (LC-MS). Analysis revealed high percentage of positive samples for all tested compounds (90-100% except from BePB (15.8%)). The mean concentration levels were 4501.2 pg/mg (17.6-27,437.0 pg/mg) for MePB; 510.1 pg/mg (11.0-4224.5 pg/mg) for EtPB; 22.9 pg/mg (2.1-66.6 pg/mg) for BePB; 237.1 pg/mg (1.8-2513.7 pg/mg) for BuPB and 245.0 pg/mg (8.8-8070.2 pg/mg) for TCS. Statistical analysis of both analytical results and questionnaires' data showed that the frequent use of personal care and hygiene products, such as makeup, hairspray and sunscreens, is correlated with higher levels of PBs in hair of the pregnant women. Additionally, positive correlation was observed between the BePB levels in hair and the infants' height. Finally, no other correlation was observed between endocrine disruptors' levels in maternal hair and infants' somatometric characteristics or health condition. Our study is the first one that determined PBs and TCS levels in hair samples, simultaneously. At the same time, correlation of the detected levels with the use of personal care products was accomplished, leading to significant association of BePB levels in hair of pregnant women with infants' height.

Anthropometric measures at age 3 years in associations with prenatal and postnatal exposures to chlorophenols

BACKGROUND

Chlorophenols (CPs), suspected as endocrine disrupting chemicals, exposure during early life may contribute to body size. However, limited human data with inconsistent findings have examined the developmental effects of CPs exposure.

OBJECTIVE

To explore associations between prenatal and postnatal CPs exposure and anthropometric parameters in children aged 3 years.

METHODS

A subset of 377 mother-child pairs with urinary five CP concentrations were enrolled from a prospective birth cohort. Generalized linear models were conducted to evaluate associations of CPs exposure with children's anthropometric measures.

RESULTS

Maternal urinary 2,4,6-trichlorophenol (2,4,6-TCP) concentrations were significantly negatively associated with weight z scores [regression coefficient (β) = -0.51, 95% confidence interval (CI): -0.96, -0.05; p = 0.01], weight for height z scores (β = -0.54, 95% CI: -1.02, -0.06; p = 0.01) and body mass index (BMI) z scores (β = -0.53, 95% CI: -1.03, -0.03; p = 0.01) of children aged 3 years, after adjustment for potential confounders and postnatal CPs exposure. In the sex-stratified analyses, these inverse associations remained among boys, while in girls, positive associations of prenatal 2,4,6-TCP exposure with weight for height z scores and BMI z scores were observed. Postnatal exposure to 2,5-diclorophenol (2,5-DCP) was positively associated with weight z scores (β = 0.26, 95% CI: 0.02, 0.50; p = 0.04), after controlling for possible confounders and maternal CPs exposure during pregnancy. Considering potential sex-specific effects, these associations were only observed in girls.

CONCLUSIONS

Our findings indicate that prenatal 2,4,6-TCP exposure and postnatal 2,5-DCP exposure may have adverse and sex-specific effects on children's physical development.

Associations of prenatal and childhood chlorpyrifos exposure with Neurodevelopment of 3-year-old children

Chlorpyrifos (CPF), an organophosphate insecticide, has been linked to adverse neurodevelopmental effects in animal studies. However, little is known about long-term neurotoxicity of early-life CPF exposure in humans. We aimed to evaluate the associations of both prenatal and early childhood CPF exposure with neurodevelopment of children. In this observational study based on Sheyang Mini Birth Cohort, pregnant women were recruited from an agricultural region between June 2009 and January 2010, and their children were followed up from birth to age three. Urinary 3,5,6-Trichloro-2-pyridinol (TCPy), a specific metabolite of CPF, was quantified using large-volume-injection gas chromatography-tandem mass spectrometry. Developmental quotients (DQs) of children in motor, adaptive, language, and social areas were assessed by trained pediatricians. Data from 377 mother-child pairs were used in the current study. Associations between CPF exposure and neurodevelopmental indicators were estimated using generalized linear models with adjustment for potential confounders. The median concentrations of TCPy in maternal and children's urine were 5.39 μg/L and 5.34 μg/L, respectively. No statistically significant association was found between maternal urinary TCPy concentrations and children neurodevelopment. While for postnatal exposure, we found lower motor area DQ score 0.61 [95% confidence interval (CI): -1.13, -0.09; p = 0.02] and social area DQ score 0.55 (95% CI: -1.07, -0.03; p = 0.04) per one-unit increase in the ln-transformed childhood urinary TCPy concentrations. Further stratification by sex indicated that the inverse associations were only observed in boys, but not in girls. Our findings suggest that adverse neurodevelopmental effects were associated with early childhood CPF exposure, but not prenatal exposure. Additional longitudinal studies are needed to replicate these results and to further understand the toxicological mechanisms of CPF.

Paraben Toxicology

Parabens now being formally declared as the American Contact Dermatitis Society (non)allergen of the year, the allergologic concerns regarding parabens raised during the past century are no longer a significant issue. The more recent toxicological concerns regarding parabens are more imposing, stemming from the gravity of the noncutaneous adverse health effects for which they have been scrutinized for the past 20 years. These include endocrine activity, carcinogenesis, infertility, spermatogenesis, adipogenesis, perinatal exposure impact, and nonallergologic cutaneous, psychologic, and ecologic effects. To assert that parabens are safe for use as currently used in the cosmetics, food, and pharmaceutical industries, all toxicological end points must be addressed. We seek to achieve perspective through this exercise: perspective for the professional assessing systemic risk of parabens by all routes of exposure. The data reviewed in this article strive to provide a balanced perspective for the consumer hopefully to allay concerns regarding the safety of parabens and facilitate an informed decision-making process. Based on currently available scientific information, claims that parabens are involved in the genesis or propagation of these controversial and important health problems are premature. Haste to remove parabens from consumer products could result in their substitution with alternative, less proven, and potentially unsafe alternatives, especially given the compelling data supporting the lack of significant dermal toxicity of this important group of preservatives.

Prenatal exposure to parabens and anthropometric birth outcomes: A systematic review

Parabens are ubiquitous substances commonly used as preservatives because of their antibacterial activity. The estrogenic activity of parabens may cause undesirable health effects and adverse birth outcomes. The objective of the present systematic review was to investigate the association between prenatal exposure to parabens and anthropometric birth outcomes. PubMed, Web of Science, Scopus, and Embase databases were systematically searched until April 18, 2018. Of 326 records that remained after removing duplicates, 6 original articles were included in the final analysis after excluding irrelevant articles. The included studies indicated that most of the pregnant mothers were exposed to parabens, especially methyl and propyl parabens. However, no definitive association was found between the prenatal urinary concentration of parabens and birth weight or head circumference. In addition, a positive but non-significant association was detected between birth length and maternal exposure to parabens. The present systematic review revealed that assessment of significant associations in current epidemiological studies is impermissible due to methodological limitations and absence of inter-study consistency. Furthermore, because of the complexity of the effect of environmental factors on health, future large-scale studies with proper study design are required to investigate the effect of parabens exposure on birth outcomes.

Parabens and triclosan in shellfish from Shenzhen coastal waters: Bioindication of pollution and human health risks

This work aimed to determine the concentrations of parabens and triclosan (TCS) in shellfish from coastal waters of Shenzhen, South China. A method of isotope dilution with high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was used to determine TCS and five paraben analogues, including methyl paraben (MeP), ethyl paraben (EtP), propyl paraben (PrP), butyl paraben (BuP), and benzyl paraben (BeP), in 186 shellfish samples covering eight species. Concentrations of parabens and TCS were 0.13-25.5 ng/g wet weight (ww) and <LOQ-6.51 ng/g ww, respectively, indicating their ubiquitous contamination in Shenzhen coastal waters. MeP was the most predominant paraben, followed by EtP and PrP. These three analogues accounted for more than 95% of the total concentrations of parabens. The "high" estimated daily intakes of parabens and TCS with the 95th percentage concentrations were estimated to be 2.15-26.1 and 0.41-10.3 ng/kg bw/day, respectively, much lower than the acceptable dietary intakes of parabens (1 × 10⁷ ng/kg bw/day) and TCS (200 ng/kg bw/day), indicating no significant human health risks from shellfish consumption in the studied region. To our knowledge, this is the first report on the occurrences of parabens and TCS in shellfish products from Shenzhen coastal waters.

Parabens and their effects on the endocrine system

Preservatives (ingredients which inhibit growth of microorganisms) are used to prolong shelf life of various foods, cosmetics, and pharmaceutical products. Parabens are one of the most popular preservatives used in the aforementioned products and is currently being used worldwide. Parabens are easily absorbed by the human body. Thus, it is important to discuss about their safety with respect to human physiology. In view of the current literature, which classifies parabens as a group of endocrine disrupting chemicals (EDCs), it seems that the precise assessment of their influence on the human endocrine system is particularly important. Disruption of the endocrine homoeostasis might lead to multidirectional implications causing disruption of fitness and functions of the body. Therefore, in this review article, we aimed to summarize the current literature on properties, occurrence, and metabolism of parabens as well as to present recent progress in knowledge about their influence on the human endocrine system.

Urinary concentrations of environmental phenols and their association with type 2 diabetes in a population in Jeddah, Saudi Arabia

A few epidemiologic studies suggest that exposure to bisphenol A (BPA) is associated with type 2 diabetes mellitus (T2DM). However, little is known about association between other phenolic endocrine disrupting chemicals (EDCs) and T2DM. In this case-control study, we measured urinary concentrations of 23 phenolic EDCs in 101 individuals from Jeddah, Saudi Arabia, to examine the association of parabens, antimicrobials, bisphenols, benzophenones and bisphenol A diglycidyl ethers with T2DM. Urine samples were collected from 54 T2DM cases and 47 non-diabetic individuals (controls), aged 28-68 years old, during 2015-2016. Unconditional logistic regression was performed to estimate odd ratios (ORs) for the association between diabetes and EDC exposures after adjusting for confounders including age, gender, nationality, smoking status and occupation. Age from 40 to 59 years (OR 5.56, 95% CI 2.20-14.0) and smoking status (OR 2.92, 95% CI 1.25-6.79) showed significant positive associations with T2DM. After adjusting for potential confounders, we found that T2DM cases had high urinary levels of parabens (i.e., methyl- (MeP), ethyl- (EtP), propyl- (PrP) and 4-hydroxy benzoic acid (4-HB)), bisphenols (i.e., bisphenols A (BPA) and F (BPF)), and benzophenone (i.e., 4-hydroxybenzophenone (4-OH-BP)) relative to the controls. Individuals in the 4th quartile for urinary concentrations of MeP, EtP, PrP, 4-HB and BPF and in the 3rd quartile for BPA and 4-OH-BP showed over a 6-fold increase in the odds of having diabetes compared with those in the first quartile. Overall, our study shows that urinary levels of multiple phenolic EDCs were associated with increased risk for diabetes. Further prospective studies are required to verify these associations.

Measurement of endocrine disrupting and asthma-associated chemicals in hair products used by Black women

BACKGROUND

Personal care products are a source of exposure to endocrine disrupting and asthma-associated chemicals. Because use of hair products differs by race/ethnicity, these products may contribute to exposure and disease disparities.

OBJECTIVE

This preliminary study investigates the endocrine disrupting and asthma-associated chemical content of hair products used by U.S. Black women.

METHODS

We used gas chromatography/mass spectrometry (GC/MS) to test 18 hair products in 6 categories used by Black women: hot oil treatment, anti-frizz/polish, leave-in conditioner, root stimulator, hair lotion, and relaxer. We tested for 66 chemicals belonging to 10 chemical classes: ultraviolet (UV) filters, cyclosiloxanes, glycol ethers, fragrances, alkylphenols, ethanolamines, antimicrobials, bisphenol A, phthalates, and parabens.

RESULTS

The hair products tested contained 45 endocrine disrupting or asthma-associated chemicals, including every targeted chemical class. We found cyclosiloxanes, parabens, and the fragrance marker diethyl phthalate (DEP) at the highest levels, and DEP most frequently. Root stimulators, hair lotions, and relaxers frequently contained nonylphenols, parabens, and fragrances; anti-frizz products contained cyclosiloxanes. Hair relaxers for children contained five chemicals regulated by California's Proposition 65 or prohibited by EU cosmetics regulation. Targeted chemicals were generally not listed on the product label.

CONCLUSIONS

Hair products used by Black women and children contained multiple chemicals associated with endocrine disruption and asthma. The prevalence of parabens and DEP is consistent with higher levels of these compounds in biomonitoring samples from Black women compared with White women. These results indicate the need for more information about the contribution of consumer products to exposure disparities. A precautionary approach would reduce the use of endocrine disrupting chemicals in personal care products and improve labeling so women can select products consistent with their values.

Parabens and measures of adiposity among adults and children from the U.S. general population: NHANES 2007-2014

BACKGROUND

Emerging experimental studies suggest that parabens could affect metabolism by altering the microbiome or signaling pathways involved in adipocyte differentiation. While human exposure to parabens is widespread, epidemiologic studies assessing the role of these chemicals on adiposity measures are scarce.

OBJECTIVE

We examined associations of parabens with adiposity measures among adults and children in the U.S. general population.

METHODS

We conducted covariate-adjusted linear and logistic regression models to examine associations between urinary biomarker concentrations of four parabens (butyl-BP, ethyl-EP, methyl-MP, and propyl paraben-PP) and measures of adiposity (obesity; body mass index, BMI or BMI z-score; and waist circumference) among 4730 adults (2007-2014) and 1324 children (2007-2012), participating in the National Health and Nutrition Examination Survey. We also assessed heterogeneity of associations by gender.

RESULTS

We generally observed significant inverse associations between adiposity measures and paraben biomarker concentrations among adults (BP, EP, MP, PP) and children (MP). For example, adjusted prevalence odds ratios (95% confidence intervals, CI) for obesity per a ten-fold increase in MP concentrations were 0.64 (95% CI: 0.55, 0.73) for adults and 0.71(95% CI: 0.52, 0.95) for children. Strength of inverse associations typically increased monotonically with increasing paraben exposure quartiles; and, in general, inverse associations were more pronounced among females. Associations remained when controlling for other phenolic compounds previously linked with adiposity measures.

CONCLUSIONS

In this cross-sectional study of adiposity measures and parabens, we observed consistent inverse associations in a representative sample of U.S adults and children. Further studies are warranted to confirm our findings, examine the potential role of paraben sequestration in adipose tissue, and elucidate mechanisms by which parabens could alter metabolism.