Evaluation of ecotoxicological effects of benzophenone UV filters: Luminescent bacteria toxicity, genotoxicity and hormonal activity

Ecotoxicological assessment of UV filters benzophenone-3 and TiO2 nanoparticles, isolated and in a mixture, in developing zebrafish (Danio rerio)

The increasing use of UV filters, such as benzophenone-3 (BP-3) and titanium dioxide nanoparticles (TiO2 NPs), has raised concerns regarding their ecotoxicological effects on the aquatic environment. The aim of the present study was to examine the embryo-larval toxicity attributed to BP-3 or TiO2 NPs, either alone or in a mixture, utilizing zebrafish (Danio rerio) as a model after exposure to environmentally relevant concentrations of these compounds. Zebrafish embryos were exposed to BP-3 (10, 100, or 1000 ng/L) or TiO2 NPs (1000 ng/L) alone or in a mixture (BP-3 10, 100, or 1000 ng/L plus 1000 ng/L of TiO2 NPs) under static conditions for 144 hr. After exposure, BP-3 levels were determined by high-performance liquid chromatography (HPLC). BP-3 levels increased in the presence of TiO2 NPs, indicating that the BP-3 degradation decreased in the presence of the NPs. In addition, in the presence of zebrafish, BP-3 levels in water decreased, indicating that zebrafish embryos and larvae might absorb BP-3. Data demonstrated that, in general, environmentally relevant concentrations of BP-3 and TiO2 NPs, either alone or in a mixture, did not significantly induce changes in heart and spontaneous contractions frequencies, levels of reactive oxygen species (ROS), morphological and morphometric parameters as well as mortality rates during 144 hr exposure. However, the groups exposed to TiO2 NPs alone and in a mixture with BP-3 at 10 ng/L exhibited an earlier significant hatching rate than the controls. Altogether, the data indicates that a potential ecotoxicological impact on the aquatic environment exists.

Aquatic toxicity, bioaccumulation potential, and human estrogen/androgen activity of three oxo-Liquid Organic Hydrogen Carrier (oxo-LOHC) systems

The Liquid Organic Hydrogen Carrier (LOHC) technology offers a technically attractive way for hydrogen storage. If LOHC systems were to fully replace liquid fossil fuels, they would need to be handled at the multi-million tonne scale. To date, LOHC systems on the market based on toluene or benzyltoluene still offer potential for improvements. Thus, it is of great interest to investigate potential LOHCs that promise better performance and environmental/human hazard profiles. In this context, we investigated the acute aquatic toxicity of oxygen-containing LOHC (oxo-LOHC) systems. Toxic Ratio (TR) values of oxo-LOHC compounds classify them baseline toxicants (0.1 < TR < 10). Additionally, the mixture toxicity test conducted with D. magna suggests that the overall toxicity of a benzophenone-based system can be accurately predicted using a concentration addition model. The estimation of bioconcentration factors (BCF) through the use of the membrane-water partition coefficient indicates that oxo-LOHCs are unlikely to be bioaccumulative (BCF < 2000). None of the oxo-LOHC compounds exhibited hormonal disrupting activities at the tested concentration of 2 mg/L in yeast-based reporter gene assays. Therefore, the oxo-LOHC systems seem to pose a low level of hazard and deserve more attention in ongoing studies searching for the best hydrogen storage technologies.

Prenatal exposure to benzophenone-type UV filters and the associations with neonatal birth outcomes and maternal health in south China

Benzophenone (BP)-type UV filters are commonly added to sunscreens and cosmetics to protect against UV radiation for human skin and hair. As a result, BPs are ubiquitous in the environment and human body, and their endocrine-disrupting characteristics have been a hot topic of discussion. However, our knowledge regarding the detrimental effects of prenatal exposure to BPs on pregnant women and their offspring remains limited. To fill this gap, we determined five BP derivatives in 600 serum samples obtained from pregnant women. All the target analytes, except 2,4-dihydroxybenzophenone (BP-1), have achieved a 100 % detection rate. The most prevalent compound was 2-hydroxy-4-methoxybenzophenone (BP-3), with a median concentration of 0.545 ng/mL. Significant and positive correlations were observed among BP derivatives, indicating both endogenous metabolism and common external sources. Utilizing Bayesian kernel machine regression (BKMR) and quantile-based g-computation (QGC) models, we found relationships between BP exposure and reduced neonatal birth weight (BW) and birth chest circumference (BC) during the third trimester. Notably, the adverse effect of BPs on birth size was sex-specific. Moreover, triglyceride (TG) was identified as a potential mediator of the effect of BPs on blood pressure, and co-exposure to BPs was linked to disruptions in thyroid hormone levels and glucose regulation. Further research is warranted to unravel the toxicity of BPs and their detrimental effects on pregnant women and fetuses.

Photostability evaluation of manidipine tablets and structural determination of its photoproducts

Manidipine (MP) is a dihydropyridine drug, which is treated for the reduction of high blood pressure. The aim of this study is to clarify the photochemical behavior of MP in the case of ultraviolet light (UV) irradiation for MP tablets (Calslot® tablets). The tablets and its altered forms (powders and suspensions) were UV-irradiated using a black light, and residual amounts of active pharmaceutical ingredients (APIs) were monitored by high-performance liquid chromatography (HPLC). Due to the photoproducts of MP were detected in HPLC chromatograms, the elucidation of their chemical structures was carried out utilizing electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS). As a result, APIs in Calslot® tablets were almost completely photodegraded in the case that Calslot® tablets were suspended in an aqueous media along with the generation of some MP photoproducts. LC-ESI-MS/MS analysis clarified the chemical structures of three MP photoproducts, indicating that they were a pyridine analogue, benzophenone and a hydrolysate. Benzophenone was a main MP photoproduct. It was possible that MP might be firstly oxidized to form its pyridine analogue, followed by the oxidation of a dimethyl methylene moiety. This moiety seemed to be eliminated as a benzophenone, and the cleavage of an ester bond of the residual moiety resulted in the generation of a hydrolysate. Finally, toxicological potencies of MP and its photoproducts were predicted in silico toxicity evaluation, suggesting some of biological effects of the photoproducts might be altered compared with MP.

Computational study on the endocrine-disrupting metabolic activation of Benzophenone-3 catalyzed by cytochrome P450 1A1: A QM/MM approach

Predicting the metabolic activation mechanism and potential hazardous metabolites of environmental endocrine-disruptors is a challenging and significant task in risk assessment. Here the metabolic activation mechanism of benzophenone-3 catalyzed by P450 1A1 was investigated by using Molecular Dynamics, Quantum Mechanics/Molecular Mechanics and Density Functional Theory approaches. Two elementary reactions involved in the metabolic activation of BP-3 with P450 1A1: electrophilic addition and hydrogen abstraction reactions were both discussed. Further conversion reactions of epoxidation products, ketone products and the formaldehyde formation reaction were investigated in the non-enzymatic environment based on previous experimental reports. Binding affinities analysis of benzophenone-3 and its metabolites to sex hormone binding globulin indirectly demonstrates that they all exhibit endocrine-disrupting property. Toxic analysis shows that the eco-toxicity and bioaccumulation values of the benzophenone-3 metabolites are much lower than those of benzophenone-3. However, the metabolites are found to have skin-sensitization effects. The present study provides a deep insight into the biotransformation process of benzophenone-3 catalyzed by P450 1A1 and alerts us to pay attention to the adverse effects of benzophenone-3 and its metabolites in human livers.

Effects of the sunscreen ultraviolet filter oxybenzone (benzophenone-3) on the seagrass Posidonia oceanica (L.) Delile and its associated N2 fixers

Oxybenzone/benzophenone-3 (BP-3) is one of the most detrimental organic ultraviolet filters for marine biota, leading to legislative measures banning its presence in commercial sunscreen formulations of several countries. It remains poorly explored how this contaminant is currently threatening the persistence of critical ecosystems for conservation in the Mediterranean, such as Posidonia oceanica meadows, but it is essential for promoting sustainable coastal tourism. Our investigation aimed to determine the effects of BP-3 on P. oceanica under a short-term laboratory setup, recreating summer conditions while testing three environmentally relevant concentrations for Mallorca, Spain (minimum: 53.6 ng L-1, maximum: 557.5 ng L-1 and increased: 1115 ng L-1) and a control (0 ng L-1). Primary productivity was unaffected by the treatments, however, a reduction in leaf chlorophyll content and nitrogen fixation activity associated with rhizomes was evidenced under BP-3 addition. This may be related with oxidative damage, as reactive oxygen species production and catalase activity in P. oceanica leaves were the highest even at minimum BP-3 concentrations. Alkaline phosphatase rates showed inverted trends between old leaves and rhizomes, being enhanced in the former under BP-3 addition and reduced in the latter. These results are of great relevance for the future management of P. oceanica meadows, elucidating that even minimum concentrations of BP-3 reported in coastal waters of Mallorca can induce elevated levels of oxidative stress in the seagrass, that lead to impairments in its photosynthetic pigments production and supply of essential nutrients through belowground tissues.

Microbial consortia degrade several widely used organic UV filters, but a number of hydrophobic filters remain recalcitrant to biodegradation

Organic UV filters are important ingredients in many personal care products, including sunscreens. Evaluating the biodegradability of organic UV filters is key to estimate their recalcitrance and environmental fate and thus central to their overall environmental risk assessment. In order to further understand the degradation process, the aim was to investigate whether specific consortia could degrade certain UV filters. Several bacterial strains were isolated from enrichment cultures actively degrading octocrylene (OC), butyl methoxydibenzoylmethane (BM), homosalate (HS), and 2-ethylhexyl salicylate (ES) and were utilized to construct an in-house consortium. This synthetic consortium contained 27 bacterial strains and degraded OC, BM, HS, and ES 60-80% after 12 days, but not benzophenone-3 (BP3), methoxyphenyl triazine (BEMT), methylene bis-benzotriazolyl tetramethylbutylphenol (MBBT), diethylhexyl butamido triazone (DBT), ethylhexyl triazone (EHT), or diethylamino hydroxybenzoyl hexyl benzoate (DHHB). Furthermore, several commercial microbial mixtures from Greencell were tested to assess their degradation activity toward the same organic UV filters. ES and HS were degraded by some of the commercial consortia, but to a lesser extent. The rest of the tested UV filters were not degraded by any of the commercial bacterial mixes. These results confirm that some organic UV filters are recalcitrant to biodegradation, while others are degraded by a specific set of microorganisms.

Acute toxicity assessment of nine organic UV filters using a set of biotests

UV filters in environmental compartments are a source of concern related to their ecotoxicological effects. However, little is known about UV filters' toxicity, particularly those released into the environment as mixtures. Acute toxicity of nine organic UV filters benzophenone-1, benzophenone-2, benzophenone-3, 4-methoxy benzylidene camphor, octocrylene, ethylhexyl methoxycinnamate, 2-ethylhexyl salicylate, homosalate, and butyl methoxydibenzoylmethane was determined. UV filter solutions were tested as single, binary, and ternary mixtures of various compositions. Single solutions were tested using a set of bio tests, including tests on saline crustaceans (Artemia franciscana), freshwater crustaceans (Daphnia magna), marine bacteria (Aliivibrio fischeri), and freshwater plants (Lemna minor). The tests represent different stages of the trophic chain, and hence their overall results could be used to risk assessment concerning various water reservoirs. The toxicity of binary and ternary mixtures was analyzed using the standardized Microtox® method. Generally, organic UV filters were classified as acutely toxic. Octocrylene was the most toxic for Arthemia franciscana (LC50 = 0.55 mg L-1) and Daphnia magna (EC50 = 2.66-3.67 mg L-1). The most toxic against freshwater plants were homosalate (IC50 = 1.46 mg L-1) and octocrylene (IC50 = 1.95 mg L-1). Ethylhexyl methoxycinnamate (EC50 = 1.38-2.16 mg L-1) was the most toxic for marine bacteria. The least toxic for crustaceans and plants were benzophenone-1 (EC50 = 6.15-46.78 mg L-1) and benzophenone-2 (EC50 = 14.15-54.30 mg L-1), while 4-methoxy benzylidene camphor was the least toxic for marine bacteria (EC50 = 12.97-15.44 mg L-1). Individual species differ in their sensitivity to the tested organic UV filters. An assessment of the toxicity of mixtures indicates high and acute toxicity to marine bacteria after exposition to a binary mixture of benzophenone-2 with octocrylene, 2-ethylhexyl salicylate, or homosalate. The toxicity of mixtures was lower than single solutions predicting antagonistic interaction between chemicals.

Graphical abstract

Lymnaea stagnalis and Ophryotrocha diadema as Model Organisms for Studying Genotoxicological and Physiological Effects of Benzophenone-3

Benzophenone-3 (BP-3) is a lipophilic organic compound that occurs naturally in flower pigments. Since it adsorbs ultraviolet (UV) radiation in the UVA and UVB regions, it is one of the most common UV filters found in sunscreen and cosmetic products. We explored by in vivo micronuclei (MNi) assay the genotoxic effects of BP-3 on hemocytes from the freshwater gastropod Lymnaea stagnalis. We also studied its possible toxic effects on life-history traits: body growth in L. stagnalis and egg production of both L. stagnalis and the marine polychaete worm Ophryotrocha diadema. Adult individuals were exposed to increasing concentrations of BP-3 (0.025, 0.050, 0.100, and 0.200 mg/L) once a week for 4 weeks. In L. stagnalis, exposure to BP-3 at concentrations of both 0.2 and 0.1 mg/L produced genotoxic effects on the micronuclei frequencies, but only concentrations of 0.2 mg/L affected the NBUDs frequencies. Similarly, negative effects on body growth were observed at the concentrations of 0.2 and 0.1 mg/L and a significant reduction of egg production at 0.2 mg/L. In O. diadema, a negative correlation between egg production and increasing BP-3 concentrations was observed. Our findings suggest the need for more stringent measures to reduce the presence of BP-3 in the environment.

The binding mechanism of benzophenone-type UV filters and human serum albumin: The role of site, number, and type of functional group substitutions

Benzophenone-type UV filters (BPs) are common in natural aquatic environments. They can cause endocrine disruption or other adverse effects once they enter the human body via the food chain or drinking water. The primary cause of BPs accumulation and toxicity is the transport of BPs into the human body. Functional group substitutions can have a significant impact on the interactions of BPs and transporters, resulting in a variety of impact effects. Therefore, we explored the interaction between human serum albumin (HSA, a typical transporter) and ten typical BPs [benzophenone (BP1), 2-hydroxybenzophenone (BP2), 4-hydroxybenzophenone (BP3), 2,2'-dihydroxybenzophenone (BP4), 2,4-dihydroxybenzophenone (BP5), 4,4'-dihydroxybenzophenone (BP6), 2,4,4'-trihydroxybenzophenone (BP7), 2,2',4,4'-tetrahydroxybenzophenone (BP8), 2-hydroxy-4-methoxybenzophenone (BP9), and 2,2'-dihydroxy-4-methoxybenzophenone (BP10)] to study the role of functional group substitutions in binding. The results showed that BPs could bind to HSA at site 2, with binding constants ranging from 2.01 × 10³ to 4.57 × 10⁵ L/mol. Compared to BP1, hydroxyl and methoxy substitutions enhanced the BPs-HSA binding. The combined effect of the number and site of hydroxyl substitution at BPs determined the binding strength between BPs and HSA. It was more accessible to bind HSA when BPs were substituted with para-hydroxyl (4-hydroxyl) groups than with ortho-hydroxyl (2-hydroxyl) groups. Moreover, the additional para-methoxy (4-methoxy) group increased the BP-HSA binding strength by approximately 47 times under the same hydroxyl substitution conditions. Theoretical calculations revealed that functional group substitutions increased the intermolecular binding force by increasing the negative electrostatic potential surface area of BPs, which significantly increased the electrostatic and dispersion forces between the BPs and HSA. This BPs-HSA binding decreased the α-helix of HSA and influenced the ratio of other secondary structures, including β-sheet, β-turn, and random coil of HSA. This study provides a theoretical and experimental foundation for understanding the human health risks associated with BPs.

Primary and ultimate degradation of benzophenone-type UV filters under different environmental conditions and the underlying structure-biodegradability relationships

Ten common benzophenone-based UV filters (BPs), sharing the same basic structure and differing only in their substituents, were investigated with respect to their primary and ultimate biodegradability. This study was carried out in order to gain deeper insights into the relationship between structure and biodegradability. The primary biodegradation of the selected BPs was studied in river water at environmentally relevant concentrations (1 µg/L) while varying specific, crucial environmental conditions (aerobic, suboxic, supplementation of nutrients). For this purpose, both batch and column degradation tests were performed, which allowed a systematic study of the effects. Subsequently, the ultimate biodegradation, i.e. the potential to achieve full mineralization of BPs, was examined according to OECD guideline 301 F. The results indicate that mineralization is limited to derivatives in which both aromatic rings contain substituents. This hypothesis was supported by docking simulations showing systematic differences in the orientation of BPs within the active site of the cytochrome P450 enzyme. These differences in orientation correspond to the substitution pattern of the BPs. This study provides valuable insights for assessing the environmental hazards of this class of trace organic compounds.

Occurrence, effects, and ecological risks of chemicals in sanitizers and disinfectants: A review

In response to the novel coronavirus referred to as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) – a virus that causes COVID-19 disease has led to wide use of sanitizers and disinfectants. This, in turn, triggered concerns on their potential deleterious effects to human health and the environment due to numerous chemicals incorporated in both product categories. Here, the current state of science regarding the occurrence and ecological effects of different classes of chemicals in these products (e.g., ultraviolent filters, fragrances, etc.) are summarized in different natural (e.g., rivers) and engineered (e.g., wastewater treatment plants) systems. Data collected in the literature suggests chemicals incorporated in sanitizers and disinfectants are present in the environment, and a large portion are toxic to fish, algae, and daphnia. Using the risk quotient approach based on occurrence data, we found eight chemicals that posed the highest risk to aquatic organisms in freshwater systems were benzalkonium chloride, 4-chloro-m-cresol, sodium ortho phenyl phenate, hydrogen peroxide, 1, 2-propanediol, 4-Methyl-benzilidine-camphor, ethylhexyl methoxy cinnamate, and octocrylene. Considering limited occurrence and effects information for most chemicals, further studies on environmental monitoring and potential consequences of long-term exposure in aquatic ecosystems are recommended.

Synthesis of cross-linked magnetic chitosan beads immobilised with bacteria for aerobic biodegrading benzophenone-type UV filter

Bacterial immobilisation is a technique by which bacteria are embedded into or adsorbed onto a carrier material thereby increasing bacterial tolerance to harsh environments. This technique can be used to enhance bacterial activity and to degrade pollutants. Immobilised bacterial beads that contain nanomagnetic particles allow bead recycling and reuse. In this study, our objective was to produce cross-linked nanomagnetic chitosan beads (MCBs) for the biodegradation of benzophenone-type UV filter chemicals such as 2,4-dihydroxybenzophenone (BP-1) and oxybenzone (BP-3). We found that the optimal concentration for creating these MCBs to be 1.2% by weight chitosan and 10% by weight nano-magnetite. We selected and isolated six benzophenone-n (BPs)-biodegrading bacteria identified to be various Pseudomonas spp., a Gordonia sp., and Rhodococcus zopfii; these were used to create MCBs that were able to effectively biodegrade BP-1 or BP-3 as a sole carbon source. Both BPs were effectively biodegraded and mineralised over 8 days in the presence of the selected MCB-immobilised bacterial strains. The highest pseudo-first-order constant rates for BP biodegradation were 8.7 × 10^-3 h^-1 for BP-1 (strain BP1-D) and 1.02 × 10^-3 h^-1 for BP-3 (strain BP3-1). The mechanical strength of the MCBs was measured to be above 90% based on recovered weight. The MCBs released their bacteria at rates in the range of 10⁴-10⁵ CFU/day. We also determined the pathway through which the BPs were being aerobically biodegraded based on the GC/MS profiles of the intermediates. Our findings provide a novel strategy for treating BPs via the use of reusable and recyclable MCBs that are cheap, easy and fast to synthesise.

Transformation and toxicity dynamics of polycyclic aromatic hydrocarbons in a novel biological-constructed wetland-microalgal wastewater treatment process

In this study, a novel wastewater treatment process combining sequencing batch reactor, constructed wetland and microalgal membrane photobioreactor (BCM process) was proposed, and its performance on removal, transformation and toxicity reduction of polycyclic aromatic hydrocarbons (PAHs) was intensively explored. Satisfactory PAHs removal (90.58%-97.50%) was achieved and molecular weight had significant impact on the removal pathways of different PAHs. Adsorption dominated the removal of high molecular weight PAHs, while the contribution ratio of microbial degradation increased with the decrease of molecular weight of PAHs. More importantly, it was reported for the first time that substituted PAHs (SPAHs) produced by microbial degradation of PAHs would lead to increased toxicity during the BCM process. High PAHs (75.37%-88.52%) and SPAHs removal (99.56%-100.00%) were achieved in the microalgae unit due to its abundant cytochrome P450 enzyme, which decreased the bacterial toxicity by 90.93% and genotoxicity by 93.08%, indicating that microalgae played significance important role in ensuring water security. In addition, the high quantitative relationship (R² = 0.98) between PAHs, SPAHs and toxicity exhibited by regression model analysis proved that more attention should be paid to the ecotoxicity of derivatives of refractory organic matters in wastewater treatment plants.

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.

Mediterranean seagrass Posidonia oceanica accumulates sunscreen UV filters

Certain ultra-violet filter (UVF) components of solar creams have negative impacts on coral reefs and have been prohibited in international tourism destinations (i.e., Hawaii, Florida, and Palau) to protect coral reefs. In the Mediterranean coasts which are also hotspots of international tourism and where endemic seagrass Posidonia oceanica forms extensive meadows, the accumulation of UVF components have not been studied. We report for the first time, that the rhizomes of P. oceanica internally accumulated UVFs BP3, BP4, AVO, 4MBC and MeBZT and the paraben preservative MePB. The components BP4 and MePB occurred in higher concentrations reaching up to 129 ng g^-1 dw and 512 ng g^-1 dw, respectively. This work emphasizes the need for more experimental studies on the effects of UVFs on seagrasses and check if we should follow suit to prohibit certain UVFs to protect this species as what has been done in other regions to protect corals.

Environmental Fate and Toxicity of Sunscreen-Derived Inorganic Ultraviolet Filters in Aquatic Environments: A Review

An increasing number of inorganic ultraviolet filters (UVFs), such as nanosized zinc oxide (nZnO) and titanium dioxide (nTiO2), are formulated in sunscreens because of their broad UV spectrum sunlight protection and because they limit skin damage. However, sunscreen-derived inorganic UVFs are considered to be emerging contaminants; in particular, nZnO and nTiO2 UVFs have been shown to undergo absorption and bioaccumulation, release metal ions, and generate reactive oxygen species, which cause negative effects on aquatic organisms. We comprehensively reviewed the current study status of the environmental sources, occurrences, behaviors, and impacts of sunscreen-derived inorganic UVFs in aquatic environments. We find that the associated primary nanoparticle characteristics and coating materials significantly affect the environmental behavior and fate of inorganic UVFs. The consequential ecotoxicological risks and underlying mechanisms are discussed at the individual and trophic transfer levels. Due to their persistence and bioaccumulation, more attention and efforts should be redirected to investigating the sources, fate, and trophic transfer of inorganic UVFs in ecosystems.

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.

Micropollutants and biological effects as control indexes for the operation and design of shallow open-water unit ponds to polish domestic effluent

Additional control indexes should be considered for the operation and design of post-treatment systems, as the wastewater treatment objectives are developing toward protecting the safety of ecological environments. In this study, two control indexes were selected and examined systematically in pilot-scale shallow open-water unit (SOWU) ponds for domestic effluent polishing: micropollutants and biotoxicities. The total risk quotient (RQTotal ≤ 1) and effect-based trigger value (EBT) were set as the thresholds for known micropollutants and biological effects, respectively. The results showed that RQTotal of micropollutants (n = 46) could be mitigated to an acceptable level and the luminescent bacteria toxicity was in compliance with the EBT after SOWU polishing in the warm season. The reduction of micropollutants and biotoxicities in the SOWUs both fit the k-C* model well (R2 > 0.9) in the warm and cold seasons. Finally, the k-C* model integrated with the control indexes was developed to design the SOWU dimensions, and the results indicated that a pond area of 21.7-108.5 m2 was required for every 1 m3/d of effluent when micropollutants were set as the control index, while a pond area of 3.6-18.2 m2 was required when luminescent bacteria toxicity was set as the control index.

Sunscreens’ UV Filters Risk for Coastal Marine Environment Biodiversity: A Review

Considering the rapid growth of tourism in recent years and the acknowledgement that exposure to solar UV radiation may cause skin cancer, sunscreens have been widely used by beachgoers in recent decades. UV filters contained in sunscreens, however, were recently identified as emerging pollutants in coastal waters since they accumulate in the marine environment with different adverse effects. In fact, exposure to these components was proven to be toxic to most invertebrate and vertebrate marine species. Some UV filters are linked to the production of significant amounts of reactive oxygen species (ROS), such as hydrogen peroxide, and the release of inorganic micronutrients that may alter the status of coastal habitats. Bioaccumulation and biomagnification have not yet been fully addressed. This review highlights recent progress in research and provides a comprehensive overview of the toxicological and ecotoxicological effects of the most used UV filters both on the abiotic and biotic compartments in different types of coastal areas, to gain a better understanding of the impacts on coastal biodiversity.

Variation and comparison of biotoxicity during typical biological treatment of dyeing wastewater

In present study, dyeing wastewater samples were collected from three typical dyeing wastewater treatment plants in Wujiang, Shengze and Shanghai, China. Physicochemical properties and biotoxicity indicators (luminescent bacteria acute toxicity and umu genotoxicity) were tested and the relationships among them were analyzed. The results revealed that two biotoxicity indicators varied significantly among different treatment units of three plants. After treatment by plant A, luminescent bacteria acute toxicity of dyeing wastewater reduced effectively, while umu genotoxicity increased significantly. Two biotoxicity indicators exhibited decrease and increase trends during the treatment processes of plant B and plant C, respectively. Correlation analysis indicated that there was little correlation among biotoxicity indicators and physicochemical properties, meanwhile two kinds of biotoxicity indicators were relatively independent. Therefore, it was recommended that comprehensive evaluation of dyeing wastewater toxicity needs the combination of various biotoxicity indicators, and the relationship among biotoxicity indicators and physicochemical properties of dyeing wastewater should be established individually. The results of this study would offer a general understanding and evaluation of biotoxicity during actual dyeing wastewater treatment processes and provide database for toxicity reduction and management of dyeing wastewater.

A systematic review and ecological risk assessment for organic ultraviolet filters in aquatic environments

Organic ultraviolet filters (OUVFs) are used in a wide range of manufactured products including personal care (e.g. sunscreens) and plastic items. This review summarizes the available data regarding the toxic effects of OUVFs on marine and freshwater organisms and generates the predicted no-effect concentration (PNEC) values necessary for assessing ecological risk. Through a systematic search of the literature, 89 studies were identified and ecotoxicological data extracted. Collectively, these studies described toxicity testing with 39 OUVF from 10 structural classes, with derivatives of benzophenones (49%) and camphors (16%) most studied. There was a bias towards selecting freshwater species (61%), and evaluating single OUVF effects (87%) rather than OUVF mixtures. Short-term (acute) experimentation (58%) was marginally more common than long-term (chronic) testing (42%). Reproductive, developmental, genetic, and neurological toxicity were the most commonly identified effects in aquatic organism, and were associated with molecular interactions with steroid receptors, DNA, or the production of reactive oxygen species. Species sensitivity distribution and/or assessment factors were used to calculate PNECs for 22 OUVFs and the risk quotients for 12 OUVFs. When using maximum concentrations, high risk was observed for six OUVFs in marine environments (4-methylbenzylidene-camphor, octocrylene, padimate-O, benzophenone-1, and oxybenzone, ethylhexyl-4-methoxycinnamate), and for four OUVFs in freshwater environments (ethylhexyl-4-methoxycinnamate, octocrylene, avobenzone and oxybenzone). When using median concentrations, a risk to marine environments was observed for oxybenzone. The results of this review underline that there is limited knowledge of the pathological effects of OUVFs and their metabolites in aquatic environments, and this inhibits the development of informed water-quality guidelines.

LQFM184: A Novel Wide Ultraviolet Radiation Range Absorber Compound

The use of sunscreen has become an indispensable daily routine since UV radiation is a critical environmental stress factors for human skin. This study focused on the design, synthesis, thermal/chemical stability and efficacy/safety evaluations of a new heterocyclic derivative, namely LQFM184, as a photoprotective agent. The compound showed stability when submitted under oxidative and high-temperature conditions. It also revealed an absorption at 260-340 nm (UVA/UVB), with a main band at 298 nm and a shoulder close to 334 nm. LQFM184 showed capacity to interact with other existing UV filters, promoting an increase in the sun protection factor. In relation to acute toxicity, its estimated LD₅₀ was >300-2000 mg kg^-1 , probably with a low potential of inducing acute oral systemic toxicity hazard. In addition, our data showed that this compound did not have eye irritation, skin sensitization or phototoxicity potentials. Taken together, these findings make LQFM184 a promising ingredient to be used, alone or in association with other UV filters, in cosmetic products such as sunscreens with a broad spectrum of protection.

Toxicity of UV filters on marine bacteria: Combined effects with damaging solar radiation

Organic UV filters are of emerging concern due to their occurrence and persistence in coastal ecosystems. Because marine bacteria are crucial in the major biogeochemical cycles, there is an urgent need to understand to what extent these microorganisms are affected by those chemicals. This study deciphers the impact of five common sunscreen UV filters on twenty-seven marine bacteria, combining both photobiology and toxicity analysis on environmentally relevant species. Seven bacteria were sensitive to different organic UV filters at 1000 μg L^-1, including octinoxate and oxybenzone. This is the first report demonstrating inhibition of bacterial growth from 100 μg L^-1. None of the UV filters showed any toxicity at 1000 μg L^-1 on stationary phase cells, demonstrating that physiological state was found to be a key parameter in the bacterial response to UV-filters. Indeed, non-growing bacteria were resistant to UV filters whereas growing cells exhibited UV filter dependent sensitivity. Octinoxate was the most toxic chemical at 1000 μg L^-1 on growing cells. Interestingly, photobiology experiments revealed that the toxicity of octinoxate and homosalate decreased after light exposure while the other compounds were not affected. In terms of environmental risk characterization, our results revealed that the increasing use of sun blockers could have detrimental impacts on bacterioplanktonic communities in coastal areas. Our findings contribute to a better understanding of the impact of the most common UV filters on bacterial species and corroborate the importance to consider environmental parameters such as solar radiation in ecotoxicology studies.

Removal of organic micropollutants from biologically treated greywater using continuous-flow vacuum-UV/UVC photo-reactor

Despite growing apprehension regarding the fate of organic micropollutants (MPs) of emerging concern, little attention has been paid to their presence in domestic greywater, where they mainly originate from personal care products. Many MPs are not fully removed in conventional greywater treatments and require additional treatment. Vacuum-UV radiation (VUV) can generate ·OH in situ, via water photolysis, initiating advanced oxidation process (AOP) without any chemical addition. Despite growing interest in VUV-based AOP, its performance in real-life grey- or wastewater matrices has hardly been investigated. The present study investigates the removal of triclosan (TCS) and oxybenzone (BP3), common antibacterial and UV-filter MPs, in deionized water (DIW) and in treated greywater (TGW) using combined UVC/VUV or UVC only radiation in a continuous-flow reactor. Degradation kinetics of these MPs and their transformation products (TPs) were addressed, as well as bacterial growth inhibition of the resulting reactor's effluent. In DIW, MP degradation was much faster under the combined UVC/VUV irradiation. In TGW, the combined radiation successfully removed both MPs but at lower efficiency than in DIW, as particles and dissolved organic matter (DOM) acted as radical scavengers. Filtration and partial DOM removal prior to irradiation improved the process efficiency and reduced energy requirements under the combined radiation (from 1.6 and 167 to 1.1 and 6.0 kWh m^-3·^ּorder^-1 for TCS and BP3, respectively). VUV radiation also reduced TP concentrations in the effluent. As a result, bacterial growth inhibition of triclosan solution irradiated by VUC/VUV was lower than that irradiated by UVC light alone, for UV dose > 120 mJ cm^-2.

The treatability of trace organic pollutants in WWTP effluent and associated biotoxicity reduction by advanced treatment processes for effluent quality improvement

As increasing attention is paid to surface water protection, there has been demand for improvements of domestic wastewater treatment plant (WWTP) effluent. This has led to the application of many different advanced treatment processes (ATPs). In this study, the treatability of trace organic pollutants in secondary effluent (SE) and associated biotoxicity reduction by four types of ATPs, including coagulation, granular activated carbon (GAC) adsorption, ultraviolet (UV) photolysis and photocatalysis, and ozonation, were investigated at the bench-scale. The ATPs showed different removal capacity for the 48 chemicals, which were classified into seven categories. EDCs, herbicides, bactericides and pharmaceuticals were readily degraded, and insecticides, flame retardants, and UV filters were relatively resistant to removal. During these processes, the efficiency of the ATPs in reducing four biological effects were investigated. Of the four biological effects, the estrogenic activity from SE was not detected using the yeast estrogen screen. In contrast with genotoxicity and photosynthesis inhibition, bacterial cytotoxicity posed by SE was the most difficult biological effect to reduce with these ATPs. GAC adsorption and ozonation were the most robust treatment processes for reducing the three detected biotoxicities. UV photolysis and photocatalysis showed comparable efficiencies for the reduction of genotoxicity and photosynthesis inhibition. However, coagulation only performed well in genotoxicity reduction. The effect-based trigger values for the four bioassays, that were derived from the existing environmental quality standards and from HC5 (hazardous concentration for 5% of aquatic organisms), were all used to select and optimize these ATPs for ecological safety. Conducting ATPs in more appropriate ways could eliminate the negative effects of WWTP effluent on receiving water bodies.

Differential toxicity of the UV-filters BP-3 and BP-4 in Chlamydomonas reinhardtii: A flow cytometric approach

Due to the concern about the negative effects of exposure to sunlight, UV-filters are being introduced in all kind of cosmetic formulas. Wastewater treatment plants are not able to remove and/or degrade them; consequently they find their way into rivers, lakes and oceans. These chemicals are acquiring a concerning status due to their increasingly common use and the potential risk for the environment. Benzophenone-3 (BP-3) and Benzophenone-4 (BP-4) are broad-spectrum UV-filters used for the same purpose in personal care products, insecticides and plastic bags; however, after 96 h of exposure to several concentrations of these UV-filters, the growth of C. reinhardtii was more affected by BP-3 than by BP-4, being the 96 h-EC₅₀ for growth 5 mg L^-1 and 38 mg L^-1, respectively. Based on these values Chlamydomonas reinhardtii cultures were exposed during 24 h to 2.5, 5 and 10 mg L^-1 of BP-3 and 19, 38 and 76 mg L^-1 of BP-4. A cytometric panel was carried out to evaluate the effect of sublethal concentrations of these UV-filters, thus several cytotoxicity biomarkers were analysed, including chlorophyll a fluorescence, viability, metabolic activity, oxidative stress, cytoplasmic and mitochondrial membrane potentials, and intracellular pH. BP-3 and BP-4 affect C.reinhardtii cells in a different way, showing differences for three of the examined parameters. Chlorophyll a fluorescence and mitochondrial membrane potential showed a significant increase (p < 0.05) in BP-3 and a significant decrease in BP-4, whereas viability only decreased significantly in the highest concentrations of BP-3. Regarding to the other parameters analysed, a similar pattern of cytotoxicity was observed. Growth rate, vital population and metabolic activity (esterase activity) and intracellular pH decreased significantly and cytoplasmic membrane potential and ROS levels increased significantly in cultures exposed to both pollutants.

Urinary concentration of personal care products and polycystic ovary syndrome: A case-control study

Polycystic ovary syndrome (PCOS) is one of the most common endocrine disorder among females of reproductive age. Many emerging contaminants in personal care products have been confirmed with endocrine disruptive effects. We performed a case-control study to explore the association between the concentrations of certain emerging contaminants (organic UV filters, bisphenol A, and triclosan) and the risk of PCOS. Urine samples were collected from 40 women with PCOS (case group) and 83 healthy women (control group). No significant differences were found in detection rate or total concentrations of analytes in women with PCOS and controls (p > 0.05). In addition, no association was found between certain emerging contaminants and PCOS either in an unadjusted binary logistic regression model or in a model adjusted for potential confounders. However, with stratification according to body mass index, one organic UV filter - octocrylene(OC) was significantly associated with PCOS in women with BMI ≥ 24 (adjusted OR = 1.512, 95% CI: 1.043, 2.191). It's the first time to investigate the association between exposure of organic UV filters and PCOS risk. We conclude that there is positive association between OC and PCOS risk in obese and overweight women.

Bioaccumulation and Biomagnification of 2-Ethylhexyl-4-dimethylaminobenzoate in Aquatic Animals

2-Ethylhexyl-4-dimethylaminobenzoate (EHDAB) is a commonly used organic ultraviolet filter. The bioaccumulation and biomagnification of EHDAB were investigated in two aquatic animals, the larvae of midge (Chironomus riparius) and crucian carp (Carassius carassius), and the metabolic enzyme responses in fish liver were determined. EHDAB in the larvae of midge reached a steady state within 10 days of sediment exposure. The biota-sediment accumulation factors ranged from 0.10 to 0.54, and were inversely proportional to the exposure concentrations. The EHDAB-contaminated larvae were used to feed the crucian carp. Within 28 days of feeding exposure, the EHDAB levels in fish tissues gradually increased with the increase of the exposure concentration, exhibiting an apparent concentration-dependence and time-dependence. The liver and kidneys were the main organs of accumulation, and the biomagnification factors of EHDAB ranged from 8.97 to 11.0 and 6.44 to 10.8, respectively. In addition, EHDAB significantly increased the activities of cytochrome P450 (CYP) 1A, CYP3A and glutathione S-transferase in the fish liver. Our results indicate that EHDAB may pose a risk of biomagnification in an aquatic environment and influence the biological processes of exposed organisms.

Biotoxicity of Water-Soluble UV Photodegradation Products for 10 Typical Gaseous VOCs

Ultraviolet (UV) photodegradation is increasingly applied to control volatile organic compounds (VOCs) due to its degradation capabilities for recalcitrant compounds. However, sometimes the UV photodegradation products are also toxic and can affect human health. Here, 10 VOCs at 150~200 ppm in air were treated using a laboratory-scale UV reactor with 185/254 nm irradiation, and the biotoxicity of their off-gas was studied by investigating their off-gas absorption solutions. The CO₂ increase and VOC decrease were 39~128 ppm and 0~42 ppm, respectively, indicating that the VOCs and their products were mineralized in off-gas absorption solutions. The total organic carbon (TOC) of the absorption solutions are 4~20 mg∙L⁻¹. Luminescent bacteria and Daphnia magna were used to detect the acute toxicity, and an umu assay was used to determine the genotoxic potential. Trichloroethylene showed a highest toxicity to luminescent bacteria, while chlorobenzene had the lowest toxicity. Water-soluble UV photodegradation products for styrene are very toxic to Daphnia magna. In the umu assay, the genotoxicities of off-gas absorption solutions of trichloroethylene, methylbenzene, ethyl acetate, butyl alcohol, and styrene were 51.26, 77.80, 86.89, 97.20, and 273.62 mg (4-NQO)·L⁻¹ respectively. In addition, the analysis of the genotoxicity/TOC and intermediates products indicated that the off-gas absorption solutions of styrene, trichloroethylene, and butyl alcohol contain many highly toxic substances.

Occurrence and assessment of the risk of ultraviolet filters and light stabilizers in Victorian estuaries

This reconnaissance study was undertaken to examine the occurrence of common ultraviolet filters (UVF) and light stabilizers (UVLS), and preservatives in four different estuaries in Port Philip Bay, Victoria, for the first time. In total, 11 UV filters, 10 UV stabilizers, 12 preservatives and a metabolite, and one fragrance were screened in grab samples of water and sediment using a combination of solid phase extraction and gas and liquid chromatography mass spectrometry measurement techniques. In that context, 16 of the UVF and UVLS and 5 of the preservatives screened were observed in water and/or sediment samples. There are no marine water quality guideline values for any of the fragrances, preservatives and UV filters and light stabilizers in Australia's current national water quality guidelines, so potential risk was assessed using the risk quotient (RQ) and toxic unit (TU) concepts. In that context, only two chemicals (OC and EHMC) had both an RQ above 1 and a log₁₀TU above - 3, suggesting that few of the screened chemicals would have posed an individual, short-term risk to organisms in the waters studied at the time of sampling. However, the detection of common UV filters, such as 4MBC, EHMC, OC and the common preservatives 2-PE, MP, and PB in these Victorian estuaries highlights that the existence of personal care products in the environment is not just an issue for more densley populated countries in the northern hemisphere, but also potentially of concern in Australia. And, in that context, more sampling campaigns in Port Philip Bay are of paramount importance to assess the potential risk posed by these compounds to aquatic ecosystems.

Safety of benzophenone to be used as flavouring

Benzophenone [FL-no: 07.032] has been evaluated as a flavouring substance, in FGE.69, by the EFSA Panel on Food Additives, Flavourings, Processing Aids and Materials in Contact with Food in 2008. Benzophenone was evaluated also by JECFA (2011) and by IARC (2013) based on studies that were not considered in the EFSA opinion on FGE.69. Therefore, the Commission requested the CEF Panel to carry out a review of existing literature on the safety of this flavouring substance. In the framework of the evaluation of benzophenone as a food contact material, the CEF Panel established a tolerable daily intake (TDI) of 0.03 mg/kg body weight (bw) per day (2009). In the present Opinion, the Panel considered the already existing evaluations by EFSA, JECFA, IARC and available literature data on benzophenone toxicity. Moreover, new data on the use levels of benzophenone as a flavouring substance have been provided. The Panel considers that there is no concern with respect to genotoxicity. The Panel considers the endocrine activities of benzophenone and its metabolite 4-hydroxybenzophenone as weak and not directly related to the observed toxic effects including the neoplastic effects in rodents. The Panel confirms that the conservative approach taken by EFSA (2009) to derive a TDI of 0.03 mg/kg bw for benzophenone is appropriate to cover the non-neoplastic effects in the chronic toxicity studies and the neoplastic effects induced in the rodent carcinogenicity studies. The TDI is in the same order of magnitude as the chronic dietary exposure of adults and children to benzophenone (10-20 μg/kg bw per day) for the amount of added flavouring substance. The Panel considers that the calculated TDI and exposure estimate are based on conservative assumptions. The Panel concludes that there is no safety concern for benzophenone under the current condition of use as a flavouring substance.