In vitro and in vivo screening for environmentally friendly benzophenone-type UV filters with beneficial tyrosinase inhibition activity

Organic UV filters: Occurrence, risks and (anti-)progestogenic activities in samples from the Czech aquatic environment and their bioaccumulation in fish

The occurrence, environmental risks and contribution of organic UV filters to detected (anti-)progestogenic activities were examined in samples of wastewater treatment plant influents and effluents, various surface waters and fish from the Czech Republic. Of the 20 targeted UV filters, 15 were detected in the WWTP influent samples, 11 in the effluents, and 13 in the surface water samples. Benzophenone-3, benzophenone-4, and phenyl benzimidazole sulfonic acid (PBSA) were found in all water samples. Octocrylene, UV-327 and 4-methylbenzylidene camphor exceeded the risk quotient of 1 at some sites. In the anti-progestogenic CALUX assay, 10 out of the 20 targeted UV filters were active. Anti-progestogenic activities reaching up to 7.7 ng/L, 3.8 ng/L, and 4.5 ng/L mifepristone equivalents were detected in influents, effluents, and surface waters, respectively. UV filters were responsible for up to 37 % of anti-progestogenic activities in influents. Anti-progestogenic activities were also measured in fish tissues from the control pond and Podroužek (pond with the highest number of detected UV filters) and ranged from 2.2 to 9.5 and 1.9 to 8.6 ng/g dw mifepristone equivalents, respectively. However, only benzophenone was found in fish, but it does not display anti-progestogenic activity and thus could not explain the observed activities.

Toxic effects and molecular mechanisms of estuarian crustaceans (Scylla paramamosain) exposed to five commonly used benzophenones

Benzophenones (BPs) are commonly used in personal care products like sunscreens and are increasingly being released into the environment, raising concerns about their potential ecotoxic effects. BPs as emerging environmental contaminants, little is known about their toxic effects on estuarine organisms. This study firstly investigated the toxic effects of five commonly used BPs on mud crabs (Scylla paramamosain). The crabs were exposed to varying concentrations of BPs for 14 days. The results showed that BPs caused damage to antioxidant systems in crabs. Transcriptome sequencing revealed that BP-3 and BP-1 had a greater impact on the crabs compared to the other BPs. Specifically, BP-1 and BP-3 caused severe damage to organelles and ribosomes. BP affected catalytic activity and hydrolase activity, BP-2 affected phosphoenolpyruate carboxykinase activity, and BP-4 affected tRNA aminoacylation and hydrolase activity. These findings can enhance our understanding of the ecotoxicity of BPs and may help to protect estuarine ecosystems.

Cosmetic UV filters in the environment-state of the art in EU regulations, science and possible knowledge gaps

OBJECTIVE

The aim of this work was to review the principals of environmental hazard and risk assessment (ERA) of cosmetic UV filters registered under EU REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals). Furthermore, effects as obtained from non-standardized testing methods and organisms from scientific literature were compared against the predicted no effect concentrations (PNECs) as derived based on standardized test methods for the various environmental compartments under REACH.

METHODS

The REACH dossiers at the ECHA webpage were screened for available information related to basic physico-chemical data (i.e. water solubility, octanol-water partitioning coefficient), PNECs and associated data (data basis, assessment factors (AFs)). Scientific literature was screened for available ecotoxicity data and the adverse effect levels were compared against the derived PNECs under REACH. Current approaches for environmental risk assessments of UV filters were evaluated for its applicability for a direct release scenario.

RESULTS

Under REACH, PNECs were derived for all hazardous UV filters. Although, PNECs were often derived for various environmental compartments (i.e. freshwater, marine water, sediment, soil), results from literature focused on aquatic data. Effects as observed within scientific literature matches in principle with the hazardous profile of the UV filters. Effects levels both on the acute and the chronic toxicity as retrieved from the non-standardized test organisms (literature) were above the derived PNECs under REACH. Currently, ERAs performed for cosmetic UV filters under REACH are solely tonnage driven and thus do not fully capture the use in sunscreens and associated leisure activities.

CONCLUSION

Existing EU REACH regulation is considered as sufficient to evaluate the environmental safety of UV filters used in sunscreens. To cover the direct release of UV filters due to various leisure activities into the aquatic freshwater and marine environment, an additional application-based ERA is considered necessary.

Comparison of developmental toxicity of benzophenone-3 and its metabolite benzophenone-8 in zebrafish

Benzophenone-3 (BP-3) as one of frequently used organic UV filters has been considered an emerging pollutant due to its toxicities. Benzophenone-8 (BP-8) is one of the main metabolites of BP-3 in organisms. Current reports show that BP-8 may be more toxic than BP-3. However, difference of their toxicities on embryonic development has rarely been reported. In this study, zebrafish embryos were chosen as the target organism to explore the developmental toxicities of BP-3 and BP-8. Non-targeted metabolomic analysis was performed to compare their modes of action. Results showed that BP-8 exposures led to higher bioaccumulation and lower hatching rate of zebrafish larvae than BP-3. Both BP-8 and BP-3 exposures caused behavioral abnormalities of zebrafish larvae, but no significant difference was found between them. At the metabolome level, 1 μg/L BP-3 and 1 μg/L BP-8 exposures altered neuroactive ligand-receptor interaction pathway and FoxO signaling pathway, respectively, which might be involved in the abnormal behaviors in zebrafish larvae. For higher exposure groups (30 and 300 μg/L), both BP-3 and BP-8 exposures changed metabolism of cofactors and vitamins of zebrafish larvae. Exposure of BP-3 altered the metabolism by pantothenate and CoA biosynthesis pathway, while BP-8 exposure changed riboflavin metabolism and folate biosynthesis. The above results indicated different modes of action of BP-3 and BP-8 in zebrafish embryonic development. This study sheds new light to biological hazards of BP-3 due to its metabolism in aquatic organisms.

Environmentally relevant concentrations of benzophenones triggered DNA damage and apoptosis in male Chinese rare minnows (Gobiocypris rarus)

Benzophenone-type ultraviolet (UV) filters (BPs) are commonly used as sunscreen agents, fragrance enhancers and plastic additives, and are great threats to aquatic organisms due to their high detected concentrations in the aquatic environment. However, few studies on their toxicity and mechanism in fish have been clearly reported. In this study, Chinese rare minnows (Gobiocypris rarus) were exposed to benzophenone (BP), 2,4-dihydroxybenzophenone (BP-1), and 5-benzoyl-4-hydroxy-2-methoxybenzenesulfonic acid (BP-4) at 5, 50, 500 µg/L for 28 d to assess their toxicity. Transcriptomics screening showed that cell cycle, DNA replication and repair were significantly altered pathways (p < 0.05). The altered transcripts were similar to those identified by RNA-seq. DNA damage and 8-OHdG levels were significantly increased at 50 and 500 μg/L groups (p < 0.05). The DNA methylcytosine level was not significantly changed exposure to BP, BP-1 and BP-4. TUNEL assays indicated that hepatic apoptosis was significantly improved at 500 μg/L BP and BP-4 and 50 and 500 μg/L BP-1 (p < 0.05), with the significantly increasing the activity of caspase-3, -8 and -9 (p < 0.05). Molecular docking analysis revealed that BP, BP-1 and BP-4 could bind differently to caspase-3 through different binding interactions. Therefore, BP-1 induced more serious oxidative DNA damage and apoptosis by activating caspase-3 than BP and BP-4, which will provide theoretical basis and data support for ecological evaluation of aquatic organisms induced by BPs.

First transcriptome of the copepod Gladioferens pectinatus subjected to chronic contaminant exposures

Contaminants are often at low concentrations in ecosystems and their effects on exposed organisms can occur over long periods of time and across multiple generations. Alterations to subcellular mechanistic pathways in response to exposure to contaminants can provide insights into mechanisms of toxicity that methods measuring higher levels of biological may miss. Analysis of the whole transcriptome can identify novel mechanisms of action leading to impacts in exposed biota. The aim of this study was to characterise how exposures to copper, benzophenone and diclofenac across multiple generations altered molecular expression pathways in the marine copepod Gladioferens pectinatus. Results of the study demonstrated differential gene expression was observed in cultures exposure to diclofenac (569), copper (449) and benzophenone (59). Pathways linked to stress, growth, cellular and metabolic processes were altered by exposure to all three contaminants with genes associated with oxidative stress and xenobiotic regulation also impacted. Protein kinase functioning, cytochrome P450, transcription, skeletal muscle contraction/relaxation, mitochondrial phosphate translocator, protein synthesis and mitochondrial methylation were all differentially expressed with all three chemicals. The results of the study also suggested that using dimethyl sulfoxide as a dispersant influenced the transcriptome and future research may want to investigate it's use in molecular studies. Data generated in this study provides a first look at transcriptomic response of G. pectinatus exposed to contaminants across multiple generations, future research is needed to validate the identified biomarkers and link these results to apical responses such as population growth to demonstrate the predictive capacity of molecular tools.

UV-filter pollution: current concerns and future prospects

UV-filters are widely used in cosmetics and personal care products to protect users' skin from redamage caused by ultraviolet (UV) radiation from the sun. Globally, an estimated 16,000 to 25,000 tonnes of products containing UV-filters were used in 2014 with modern consumption likely to be much higher. Beyond this use in cosmetics and personal care products, UV-filters are also widely used to provide UV-stability in industrial products such as paints and plastics. This review discusses the main routes by which UV-filters enter aquatic environments and summarises the conclusions of studies from the past 10 years that have investigated the effects of UV-filters on environmentally relevant species including corals, microalgae, fish, and marine mammals. Safety data regarding the potential impact of UV-filters on human health are also discussed. Finally, we explore the challenges surrounding UV-filter removal and research on more environmentally friendly alternatives to current UV-filters.

Transcriptome aberration in mice uterus associated with steroid hormone response and inflammation induced by dioxybenzone and its metabolites

Benzophenone-type UV filters have been implicated in multiple adverse reproductive outcomes, yet the underlying processes and molecular targets on the female reproductive tract remain largely unknown. Herein, we investigated the effect of dioxybenzone, one of the widely used congeners, and its demethylated (M1) and hydroxylated (M2) metabolites on transcriptome profiles of ICR mice uterus and identified potential cellular targets in human endometrial stromal cells (HESCs) separated from normal endometrium tissues. Dioxybenzone, M1 and M2 (20 mg/kg bw/d) significantly induced transcriptome aberration with the induction of 683, 802, and 878 differentially expressed genes mainly involved in cancer, reproductive system disease and inflammatory disease. Compared to dioxybenzone, M1 and M2 exhibited a transcriptome profile more similar to estradiol in mice uterus, and subsequently promoted thicker endometrial columnar epithelial layer through upregulation of estrogen receptor target genes-Sprr2s. Dioxybenzone, M1 and M2 (0.1 or 1 μM) also exhibited estrogenic disrupting effect via increasing the mRNA expressions and production of the growth factors responsible for epithelial proliferation, including Fgfs and Igf-1 in HESCs. Additionally, the mRNA expressions of several inflammatory cytokines especially IL-1β in mice uterus and HESCs was significantly upregulated by dioxybenzone and its metabolites. Overall, we revealed that dioxybenzone and its metabolites triggered transcriptome perturbation dually associated with abnormal steroid hormone response and inflammation, both as key determinants to reproductive health risks.