Environmental contamination status with common ingredients of household and personal care products exhibiting endocrine-disrupting potential

Antifungal climbazole alters androgenic pathways in mammalian cells

Among antifungal agents used in pharmaceuticals and personal care products, the synthetic azole climbazole (CBZ; 1-(4-Chlorophenoxy)-1-(imidazol-1-yl)-3,3-dimethylbutan-2-one) acts on the fungus Malassezia. Despite concerns surrounding its effects on health, based on alterations to reproduction and steroidogenesis found in fish, little is known about its mechanism of action as an endocrine disrupting chemical (EDC) in mammalian cells. In this study, using OECD test guidelines, we investigated the effects of CBZ (i) in H295R cells, on the production of estradiol and testosterone, as well as intermediate metabolites in steroidogenesis pathway, and (ii) in HeLa9903 and AR-EcoScreen cell lines, on the transactivation of estrogen and androgen receptors. Our results are the first evidence in H295R cells, that CBZ treatment (from 0.3 μM) decreased secreted levels of testosterone and estradiol. This was associated with reduced 17α-hydroxypregnenolone and 17α-hydroxyprogesterone levels. The altered levels of these metabolites were associated with a decrease in cytochrome P450 17α-hydroxylase/17,20-lyase (Cyp17A1) activity without any effect on its protein level. CBZ was also found to exert antagonistic effects toward androgen and estrogen α receptors. These results give insights into the toxicological mechanism of action of CBZ. Many azoles share structural similarities; therefore, caution should be adopted due to their potential toxicity.

Parabens and triclosan in red swamp crayfish (Procambarus clarkii) from China: Concentrations, tissue distribution and related human dietary intake risk

Parabens (PBs) and triclosan (TCS) are commonly found in pharmaceuticals and personal care products (PPCPs). As a result, they have been extensively found in the environment, particularly in aquaculture operations. Red swamp crayfish (Procambarus clarkii) consumption has significantly risen in China. Nevertheless, the levels of PBs and TCS in this species and the associated risk to human dietary intake remain undisclosed. This study assessed the amounts of five PBs, i.e., methyl-paraben (MeP), ethyl-paraben (EtP), propyl-paraben (PrP), butyl-paraben (BuP) and benzyl-paraben (BzP), as well as TCS in crayfish taken from five provinces of the middle-lower Yangtze River. MeP, PrP and TCS showed the highest detection rates (hepatopancreas: 46-86 %; muscle: 63-77 %) since they are commonly used in PPCPs. Significantly higher levels of ∑5PBs (median: 3.69 ng/g) and TCS (median: 7.27 ng/g) were significantly found in the hepatopancreas compared to the muscle (median: 0.39 ng/g for ∑5PBs and 0.16 ng/g for TCS) (p < 0.05), indicating bioaccumulation of these chemicals in the hepatopancreas. The estimated daily intake values of ∑5PBs and TCS calculated from the median concentrations of crayfish were 6.44-7.94 ng/kg bw/day and 11.4-14.0 ng/kg bw/day, respectively. Although no health risk was predicted from consuming crayfish (HQ <1), consumption of the hepatopancreas is not recommended.

In vitro blastocyst implantation and trophoblast migration are disrupted by the UV filter benzophenone-3 (BP3)

Benzophenone-3 (BP3) is a common ingredient in personal care products (PCPs) due to its well-established effectiveness in absorbing UV radiation. Sunscreen products are among the most widely used PCPs-containing BP3 applied to the skin, resulting in significant human exposure to BP3 primarily through a dermal application. In the present work, we have tested the action of three environmentally relevant concentrations of BP3 (2, 20 and 200 μg/L) on an in vitro model of implantation of murine blastocysts and on migration ability of the human trophoblast cell line Swan 71. We showed that BP3 caused a significant reduction of blastocyst expansion and a delayed hatching in a non-monotonic way. Besides, embryos displayed a delayed attachment in the three BP3 groups, resulting in a smaller implantation area on the 6th day of culture: BP3(2) (0.32 ± 0.07 mm2); BP3(20) (0.30 ± 0.08 mm2) and BP3(200) (0.25 ± 0.06 mm2) in comparison to the control (0.42 ± 0.07 mm2). We also found a reduced migration capacity of the human first-trimester trophoblast cell line Swan 71 in a scratch assay when exposed to BP3: the lowest dose displayed a higher uncovered area (UA) at 6h when compared to the control, whereas a higher UA of the wound was observed for the three BP3 concentrations at 18 and 24 h of exposure. The changes in UA provoked by BP3 restored to normal values in the presence of flutamide, an androgen receptor (AR) inhibitor. These results indicate that a direct impairment on early embryo implantation and a defective migration of extravillous trophoblast cells through the androgen receptor pathway can be postulated as mechanisms of BP3-action on early gestation with potential impact on fetal growth.

Assessment of nonylphenol exposure based on global urinary concentration data and its risk analysis

Nonylphenol (NP) has been recognized as a priority hazardous substance because of its estrogenic activity and ubiquity in the environment. Therefore, it is important to understand the daily intake of NP in humans and evaluate the potential health risks of NP. The median or average estimated daily intake (EDI) of NP was estimated based on urinary NP or alkyl-chain-oxidized NP metabolites concentration data from published epidemiological studies. In brief, we acquired 34 peer-reviewed publications, which contained 14235 samples from twelve countries or regions. The global average estimated daily intake of NP was 1.003 μg/(kg bw·day), which was lower than the tolerable daily intake recommended by the Danish Veterinary and Food Authority [5 μg/(kg bw·day)]. Korea had the highest exposure level [3.471 μg/(kg bw·day)] among different countries or regions. Compared with the adult [0.743 μg/(kg bw·day)] and pregnant women [0.806 μg/(kg bw·day)] groups, the children group had the highest estimated daily intake of NP at 2.368 μg/(kg bw·day). Besides, the global NP risk hazard quotient was 0.201, and the risk hazard quotients of all countries or regions were less than 1. However, the global HQ value of the 95th quantile population was 2.299, which was much higher than 1, the potential health risk cannot be ignored and needs to be confirmed by more research. To our knowledge, this is the first study to assess the overall NP exposure levels based on published biomonitoring data, and has important implications for assessing the potential effects of NP exposure on human health. In addition, OH-NP is a robust and sensitive novel biomarker for NP, there are fewer studies on the application of this biomarker, and more studies are needed in the future for quantitative exposure and risk assessment of NP.

Parabens as environmental contaminants of aquatic systems affecting water quality and microbial dynamics

Among different pollutants of emerging concern, parabens have gained rising interest due to their widespread detection in water sources worldwide. This occurs because parabens are used in personal care products, pharmaceuticals, and food, in which residues are generated and released into aquatic environments. The regulation of the use of parabens varies across different geographic regions, resulting in diverse concentrations observed globally. Concentrations of parabens exceeding 100 μg/L have been found in wastewater treatment plants and surface waters while drinking water (DW) sources typically exhibit concentrations below 6 μg/L. Despite their low levels, the presence of parabens in DW is a potential exposure route for humans, raising concerns for both human health and environmental microbiota. Although a few studies have reported alterations in the functions and characteristics of microbial communities following exposure to emerging contaminants, the impact of the exposure to parabens by microbial communities, particularly biofilm colonizers, remains largely understudied. This review gathers the most recent information on the occurrence of parabens in water sources, as well as their effects on human health and aquatic organisms. The interactions of parabens with microbial communities are reviewed for the first time, filling the knowledge gaps on the effects of paraben exposure on microbial ecosystems and their impact on disinfection tolerance and antimicrobial resistance, with potential implications for public health.

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.

Systematic evidence mapping informs a class-based approach to assessing personal care products and pubertal timing

BACKGROUND

Personal care products (PCPs) contain many different compounds and are a source of exposure to endocrine disrupting chemicals (EDCs), including phthalates and phenols. Early-life exposure to EDCs commonly found in PCPs has been linked to earlier onset of puberty.

OBJECTIVE

To characterize the human and animal evidence on the association between puberty-related outcomes and exposure to PCPs and their chemical constituents and, if there is sufficient evidence, identify groups of chemicals and outcomes to support a systematic review for a class-based hazard or risk assessment.

METHODS

We followed the OHAT systematic review framework to characterize the human and animal evidence on the association between puberty-related health outcomes and exposure to PCPs and their chemical constituents.

RESULTS

Ninety-eight human and 299 animal studies that evaluated a total of 96 different chemicals were identified and mapped by key concepts including chemical class, data stream, and puberty-related health outcome. Among these studies, phthalates and phenols were the most well-studied chemical classes. Most of the phthalate and phenol studies examined secondary sex characteristics and changes in estradiol and testosterone levels. Studies evaluating PCP use and other chemical classes (e.g., parabens) had less data.

CONCLUSIONS

This systematic evidence map identified and mapped the published research evaluating the association between exposure to PCPs and their chemical constituents and puberty-related health outcomes. The resulting interactive visualization allows researchers to make evidence-based decisions on the available research by enabling them to search, sort, and filter the literature base of puberty-related studies by key concepts. This map can be used by researchers and regulators to prioritize and target future research and funding to reduce uncertainties and address data gaps. It also provides information to inform a class-based hazard or risk assessment on the association between phthalate and phenol exposures and puberty-related health outcomes.