Bioaccumulation and biomagnification of ultraviolet absorbents in marine wildlife of the Pearl River Estuarine, South China Sea

Review of the environmental fate and effects of two UV filter substances used in cosmetic products

Sunscreens containing UV filters, such as octocrylene (OCR) and butyl-methoxydibenzoylmethane (BMDBM), have been increasingly used to protect human skin against UV radiation. Both substances have been detected in monitoring studies in the freshwater and marine environment, and there has been concern about potential effects on aquatic organisms. In the present work, the environmental fate and occurrence, bioaccumulation and ecotoxicity including endocrine effects of OCR and BMDBM are reviewed focusing on the aquatic environment. The two UV filters have low water solubilities and a high sorption potential. The available data indicate that OCR is poorly biodegradable. BMDBM lacks anaerobic and inherent biodegradability. However, it was biodegraded to variable degrees in simulation studies. Measured concentrations in the freshwater and marine environment were found to vary considerably between sites, depending on the extent of recreational activities or wastewater discharges. While the bioconcentration factor of OCR in fish is below the threshold value for bioaccumulation according to EU REACH, the available data for BMDBM do not allow a definitive conclusion on its bioaccumulation potential. Analysis of the aquatic toxicity data showed that data quality was often limited, e.g. in the case of effect concentrations substantially exceeding maximum achievable dissolved concentrations. Up to their limit of water solubility, OCR and BMDBM showed no toxicity to microorganisms, algae, and corals, and no acute toxicity to daphnids and fish. In chronic daphnid tests, OCR was highly toxic, whereas BMDBM lacked toxicity. Reliable water-sediment toxicity tests are required to further evaluate possible effects on benthic invertebrates. The available data do not provide evidence for endocrine effects of the two UV filters on fish. In order to assess potential environmental risks caused by OCR and BMDBM, a validated exposure model for estimating direct emission of UV filters into the aquatic environment and data from systematic, longer-term monitoring studies are needed.

Avobenzone and nanoplastics affect the development of zebrafish nervous system and retinal system and inhibit their locomotor behavior

The use of cosmetics is growing with each passing day, arousing widespread attention to their ingredients. Avobenzone (AVO) and nanoplastics (NPs) are typical ingredients in cosmetics, which coexist in the aquatic environment and have a combined effect on aquatic organisms. In this study, the accumulation of AVO and NPs in zebrafish larvae and effects on gene expression and enzymatic activity related to nervous functions, and locomotor behavior were investigated. AVO and NPs accumulated continuously in zebrafish, and the combined exposure enhanced AVO accumulation. After recovery, the accumulated concentrations of AVO and NPs in zebrafish remained unchanged, suggesting that AVO and NPs could not be eliminated in 72 h. The genes regulated nervous system development were affected mainly by AVO exposure, while the genes regulated retinal system development were affected by NPs exposure. Single and combined exposures of AVO and NPs affected the activities of acetylcholinesterase and antioxidant enzymes in zebrafish, and superoxide dismutase activity could not return to normal level after 72 h of recovery period. The locomotor activity of zebrafish larvae was significantly inhibited by AVO and NPs, which might be related to the alterations in functions of nervous system development and retinal system development as well as the interference of neurotransmitter system and antioxidant system.

Bioaccumulation and trophic transfer of organic ultraviolet absorbents in the food web of a freshwater lake: Implications for risk estimation

Organic ultraviolet absorbents (UVAs) are increasingly reported in environmental matrices and organisms. However, available information on the bioaccumulation of UVAs in freshwater species is insufficient and their trophodynamics in lake food webs remain unknown. We measured the concentrations of twelve UVAs in the wild species from Lake Chaohu. Except for UV-320 not detected, the other UVAs were prevalent in the study species and their total concentrations were in the range of 5.44-131 ng/g dry weight, which were comparable to the concentrations reported in other waters. Compound and species-specific accumulations of UVAs in the organisms were observed. In the lake, the log-transformed concentrations of 4-methyl benzylidene camphor, octyl p-dimethylaminobenzoate, UV-326, and UV-327 related significantly to the trophic levels of species separately. The calculated trophic magnification factors (TMFs) of the four UVAs were 3.79, implying trophic magnification, and 0.18, 0.40 and 0.58, suggesting trophic dilution, respectively. These suggested that the magnification potential and the associated risks of individual UVAs in freshwater lake differed. To our knowledge, this is the first report of these TMFs in lake food webs. However, more investigation is needed to characterize their trophodynamic behaviors in lakes because food web characteristics likely affect trophic transfer of these chemicals.

Organic UV filters mixture exposure and childhood adiposity: A prospective follow-up study in China

BACKGROUND

UV filters are emerging contaminants with endocrine disrupting effects, but little is known about their health effects, especially for children.

OBJECTIVE

To assess the association between multiple organic UV filters exposure and adiposity measures and by gender in peripubertal children.

METHODS

This prospective follow-up study included 327 children aged 7-15 years old. Urinary organic UV filters including benzophenone derivatives (BP-2, BP-3), octyl dimethyl para-aminobenzoic acid (OD-PABA), ethylhexyl methoxycinnamate (EHMC) and its metabolite (4-MCA and 4'-MAP) were quantified. Six adiposity biometrics including height, weight, waist and hip circumferences, and triceps and subscapular skinfold thickness were measured with 1.5-year duration. The Bayesian kernel machine regression method was used to estimate the associations of UV filters mixture with adiposity measurements, and longitudinal analyses were then considered to further evaluate the associations between individual UV filters and trajectories of growth development using linear mixed models or generalized linear mixed models.

RESULTS

Exposure to mixture of UV filters was negatively associated with most adiposity measurements, with a reduction of 1.399 kg/m² (95% CI: -2.246 to -0.551 kg/m²) in BMI, 0.674 (95% CI: -1.045 to -0.304) in BMI z-score, 0.033 BF% (95% CI: -0.053 to -0.013), and 2.301 mm (95% CI: -3.823 to -0.78) in subscapular skinfold thickness at baseline, comparing the 75th percentile to the 25th level of UV filters mixture exposure. Consistent associations were found at follow-up. Both baseline and follow-up results suggested that EHMC was identified as the most important contributor to lower adiposity measurements, which was also confirmed by linear mixed models in longitudinal analyses. No significant effects were found in girls.

CONCLUSION

This study found that childhood organic UV filters exposure was negatively associated with adiposity measures in peripubertal boys, but not girls.

Continuous input of organic ultraviolet filters and benzothiazoles threatens the surface water and sediment of two major rivers in the Pearl River Basin

The extensive usage of organic ultraviolet filters (UV filters) and benzothiazoles (BTs) has caused continuous and widespread pollution in the aquatic environment. This study investigated the occurrence of nine organic UV filters and eight BTs in the surface water and sediment of two major drinking water source rivers in the Pearl River Basin (PRB). The detection frequencies of six organic UV filters and seven BTs were above 50% in surface water, while eight target compounds were as high as 100%. Composition profiles revealed that 2-Hydroxybenzothiazole (2-OH-BTH, 1112 ng/L) and 2-Mercaptobenzothiazole (2-SH-BTH, 426.3 ng/L) were the predominant compounds in surface water, while Octyl 4-methoxycinnamate (OMC, maximum concentration, 68.3 ng/g) and UV-329 (18.8 ng/g) were predominant in sediment. Significant positive correlations were observed between water quality parameters (temperature, total phosphorus (TP) and total nitrogen (TN)) and organic UV filters (UV-327 and UV-P), indicating the domestic discharge. The calculated annual flux of targets compounds indicated that West River (WR) promoted more BTs and UV filters to the PRB than North River (NR) (BTs: WR22, 88,517 kg/year; NR13, 15,660 kg/year; UV filters: WR22, 28,332 kg/year; NR13, 1128 kg/year). Significant relationship between the Gross Domestic Product (GDP) and annual flux of BTs (R² = 0.96, p < 0.001), and UV filters (R² = 0.88, p < 0.001) in the rivers were found by regression analysis. UV-329 was detected with medium risk (RQ > 0.1) in all WR surface water samples, and 2-SH-BTH was detected with high risk (RQ > 1) in half of the WR sediment samples. This study provides the first time reports on the organic UV filters and BTs in two major rivers in the Pearl River Basin, and further showed that these two types of contaminants are ubiquitous and with potential risks in surface water and sediment of PRB.

Simultaneous trace analysis of 10 benzophenone-type ultraviolet filters in fish through liquid chromatography-tandem mass spectrometry

We developed and validated a trace analytical method for the simultaneous determination of 10 benzophenone (BP)-type ultraviolet filters (BPs; BP, BP-1, BP-2, BP-3, BP-8, 2-hydroxybenzophenone [2-OHBP], 4-hydroxybenzophenone [4-OHBP], 4-methylbenzophenone [4-MBP], methyl-2-benzoylbenzoate [M2BB], and 4-benzoylbiphenyl [PBZ]) to analyze BPs in 110 commercial fish samples. The quick, easy, cheap, effective, rugged, and safe (QuEChERS) technique coupled with ultrahigh-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) was employed. The developed method exhibited satisfactory linearity (R² > 0.993), favorable precision with intraday and interday relative standard deviation ranges of 1.0%-26.6% and 2.3%-29.3%, respectively, and a limit of detection ranging from 0.001 to 0.1 ng/g. BP and 2-OHBP were detected in 100% of the samples; BP-3, 4-OHBP, PBZ, and 4-MBP were detected in >70% of the samples; M2BB was detected in 33% of the samples, and BP-2 and BP-8 were not detected. Higher mean (minimum-maximum) levels of 2-OHBP and BP were found in fish samples with low lipid content, ranging from 18 (1.1-218.3) to 10 (0.5-45.4) ng/g, and those with high lipid content, ranging from 22 (1.5-76.4) to 9.6 (5.2-18.5) ng/g; low levels of the remaining six BPs were found, ranging from 0.01 to 0.9 ng/g. The mean 2-OHBP levels were 21.3, 14.4, and 30.2 ng/g for fish samples obtained from aquaculture in Taiwan, the wild in Taiwan, and different countries, respectively, with levels up to 218.3 ng/g (field eel) for a sample from Indonesia. BPs may not pose a health risk to Taiwanese adults through the consumption of fish; however, additional studies are needed to examine the risk that these contaminants may pose to ecosystems and human health.

Influence of suspended sediment on the bioavailability of benzophenone-3: Focus on accumulation and multi-biological effects in Daphnia magna

The UV-filter benzophenone-3 (BP3) tends to associate with suspended sediment (SPS) due to hydrophobicity, which could alter its toxicological effects on non-target aquatic organisms. In this study, the freshwater cladoceran Daphnia magna (D. magna) was selected as a model organism to investigate the impacts of the source and composition of SPS on the accumulation and multiple toxicological effects (from the molecular level to individual level) of BP3. Among the three components of SPS, amorphous organic carbon (AOC) and minerals promoted the body burden of BP3, while black carbon (BC) inhibited the bioaccumulation. The inhibition effects of BP3 on swimming and feeding behaviors of D. magna were also enhanced due to the presence of AOC and BC. Compared with BP3 exposure alone, higher oxidative stress and neurotoxicity were observed in the presence of SPS containing AOC, BC and minerals, corresponding to that superoxide dismutase, catalase and glutathione-S-transferase activities were further induced, and acetylcholinesterase activity was inhibited. Furthermore, BP3 induced mRNA expression levels of the endocrine system (ecdysone receptor, cytochrome P450 CYP314) and metabolic system (toxicant nuclear receptor HR96, P-glycoprotein), and the presence of SPS containing AOC, BC and minerals exhibited an enhanced effect. Combined with all endpoints, evident relationship was observed between the bioaccumulation level and the response of individual behavior and molecular biomarkers. The results demonstrated that the effects of SPS compositions on bioaccumulation and toxicological effects of organic UV-filters should be considered in aquatic environments.

Human metabolism and kinetics of the UV absorber 2-(2H-benzotriazol-2-yl)-4,6-di-tert-pentylphenol (UV 328) after oral administration

2-(2H-Benzotriazol-2-yl)-4,6-di-tert-pentylphenol (UV 328; CAS: 25973-55-1) is an ultraviolet light (UV) absorber which belongs to the class of hydroxy phenol benzotriazoles. Therefore, UV 328 is added to plastics and other polymers due to its photostability to prevent discoloration and prolong product stability which may result in an exposure of consumers. However, information about the toxic effects on humans and the human metabolism are still lacking. In the present study, human metabolism pathways of UV 328 and its elimination kinetics were explored. For that purpose, three healthy volunteers were orally exposed to a single dose of 0.3 mg UV 328/kg bodyweight. UV 328 and its metabolites were investigated in blood and urine samples collected until 48 and 72 h after exposure, respectively. Thereby, previously published analytical procedures were applied for the sample analysis using dispersive liquid–liquid microextraction and subsequent measurement via gas chromatography coupled to tandem mass spectrometry with advanced electron ionization. UV 328 was found to be oxidized at its alkyl side chains leading to the formation of hydroxy and/or oxo function with maximum blood concentrations at 8–10 h after exposure for UV 328-6/3-OH, UV 328-4/3-OH and UV 328-4/3-CO. In contrast, a plateau for UV 328-4/3-CO-6/3-OH levels was reached around 10 h post-dosage. The highest blood levels were found for native UV 328 at 8 h after ingestion. Furthermore, biphasic elimination kinetics in blood were revealed for almost all detected metabolites. UV 328 and its metabolites did not occur in blood as conjugates. The renal elimination kinetics were very similar with the kinetics in blood. However, the prominence of the metabolites in urine was somewhat different compared to blood. In contrast, mostly conjugated metabolites occurred for renal elimination. In urine, UV 328-4/3-CO-6/3-OH was found to be the most dominant urinary biomarker followed by UV 328-6/3-OH and UV 328-4/3-OH. In total, approximately 0.1% of the orally administered dose was recovered in urine within 72 h. Although high levels of UV 328 in blood proved good resorption and high systemic availability of the substance in the human body, the urine results revealed a rather low quantitative metabolism and urinary excretion rate. Consequently, biliary excretion as part of the enterohepatic cycle and elimination via feces are assumed to be the preferred pathways instead of renal elimination.

Bioaccumulation of estrogenic hormones and UV-filters in red swamp crayfish (Procambarus clarkii)

Estrogenic hormones and organic ultraviolet-filters (UV-filters) have attracted increased attention as endocrine disrupting chemicals (EDCs) due to their potent estrogenicity and widespread occurrence in the environment. This study investigated the accumulation of three estrogenic hormones and five UV-filters in red swamp crayfish (Procambarus clarkii). Exposure experiments were conducted for 42 days with a mixture of EDCs at two environmentally-relevant design concentrations (i.e., 500 and 5000 ng L^-1). The aqueous-phase EDC concentrations decreased over time and were re-established every two days. Within 14 days of exposure, the five UV-filters were measured at 2.2 to 265 ng g^-1 (dry weight) in crayfish tail tissue. Only one estrogenic hormone, 17β-estradiol, was detected in the crayfish at 10.4-13.5 ng g^-1. No apparent changes were observed for EDC concentrations in the tail tissue over the next four weeks of exposure. The apparent bioaccumulation factors for the EDCs ranged from 23 L (kg tail tissue, dry weight)^-1 for 4-methylbenzylidene camphor to 1050 L (kg tail tissue, dry weight)^-1 for 2-ethylhexyl-4-methoxycinnamate. EDC input was stopped after 42 days, and the more hydrophobic UV-filters (i.e., octocrylene, 2-ethylhexyl-4-methoxycinnamate, homosalate) were found to be persistent throughout a 14-d elimination period. A lyticase-assisted yeast estrogen screen demonstrated that the residual estrogenic activity of water samples aligned with (or was lower than) predictions from targeted chemical analysis. These results suggest that the transformation products did not contribute significant estrogenicity, although further analysis of endocrine disruption outcomes in crayfish is recommended.

Multimedia distribution and trophic transfer of PPCPs in the middle and lower reaches of the Yarlung Zangbo River

The increasing human presence is having an impact on plateau ecosystems, but the special environment and lack of data make it difficult to assess the real ecological risks of pharmaceutical and personal care products (PPCPs) in the river of plateau. The occurrence, distribution and trophic transfer of nineteen PPCPs were investigated in the middle and lower reaches of the Yarlung Zangbo River on the Tibetan Plateau. All the targeted PPCPs were detected in filtrated water, and seventeen PPCPs were detected in the colloid, sediment and suspended particulate matter (SPM). The distribution coefficients of colloid-infiltration water (IFW) were 1-2 orders of magnitude larger than those in the SPM-IFW, which were 1-2 orders of magnitude greater than those in the sediment-IFW. Colloids are sinks for PPCPs with up to 78.55% of the water being in the colloidal phase, in which important factors such as protein and protein-like substances are found. PPCPs in the rivers of the plateau showed high bioaccumulation ability. The fugacity-based bioaccumulation model was established and revealed that the fish in the Tibetan Plateau ingested PPCPs mainly through water instead of food and excreted them mainly through metabolism. In addition, the trophic dilution effect in the food web was observed with trophic magnification factors ranging from 0.06 to 0.22. The positive correlation between the K_d in the colloid-IFW and the bioaccumulation factors implied that natural colloids can not only regulate the behaviour of PPCPs in the environment, but also play an important role in bioaccumulation, which may affect the scientific nature of biological risk assessment.

Risks of organic UV filters: a review of environmental and human health concern studies

Organic UV filters are compounds that absorb UV irradiation by their highly conjugated structure. With the developing consciousness over the last century of the skin damage UV radiation can cause, the demand for organic UV filters has risen, for use not only in sunscreens, but also in other personal care products. The massive production and usage of these organic UV filters has resulted in extensive release into the aquatic environment, and thereby making an important group of emerging contaminants. Considering the widespread occurrence of organic UV filters in not only ambient water, but also sediment, soil and even indoor dust, their threats towards the health of living organisms have been a subject of active investigation. In this review article, we present an overall review of existing knowledge on the risks of organic UV filters from the aspects of both environmental and human health impacts. As for the environment, some organic UV filters are proven to bioaccumulate in various kinds of aquatic organisms, and further to have adverse effects on different kinds of animal models. Toxicological studies including in vivo and in vitro studies are important and effective means to ascertain the effects and mechanisms of organic UV filters on both the ecosystem and humans. Subsequent concerns arise that these compounds will affect human health in the long term. This review concludes by suggesting future lines of research based on the remaining knowledge gaps.

Mild Effects of Sunscreen Agents on a Marine Flatfish: Oxidative Stress, Energetic Profiles, Neurotoxicity and Behaviour in Response to Titanium Dioxide Nanoparticles and Oxybenzone

UV filters are potentially harmful to marine organisms. Given their worldwide dissemination and the scarcity of studies on marine fish, we evaluated the toxicity of an organic (oxybenzone) and an inorganic (titanium dioxide nanoparticles) UV filter, individually and in a binary mixture, in the turbot (Scophthalmus maximus). Fish were intraperitoneally injected and a multi-level assessment was carried out 3 and 7 days later. Oxybenzone and titanium dioxide nanoparticles induced mild effects on turbot, both isolated and in mixture. Neither oxidative stress (intestine, liver and kidney) nor neurotoxicity (brain) was found. However, liver metabolic function was altered after 7 days, suggesting the impairment of the aerobic metabolism. An increased motility rate in oxybenzone treatment was the only behavioural alteration (day 7). The intestine and liver were preferentially targeted, while kidney and brain were unaffected. Both infra- and supra-additive interactions were perceived, with a toxicodynamic nature, resulting either in favourable or unfavourable toxicological outcomes, which were markedly dependent on the organ, parameter and post-injection time. The combined exposure to the UV filters did not show a consistent increment in toxicity in comparison with the isolated exposures, which is an ecologically relevant finding providing key information towards the formulation of environmentally safe sunscreen products.

Sunscreens: UV filters to protect us: Part 2-Increasing awareness of UV filters and their potential toxicities to us and our environment

BACKGROUND

Sunscreens are topical preparations containing one or more compounds that filter, block, reflect, scatter, or absorb ultraviolet (UV) light. Part 2 of this review focuses on the environmental, ecological effects and human toxicities that have been attributed to UV filters.

METHODS

Literature review using NIH databases (eg, PubMed and Medline), FDA and EPA databases, Google Scholar, the Federal Register, and the Code of Federal Regulations (CFR).

LIMITATIONS

This was a retrospective literature review that involved many different types of studies across a variety of species. Comparison between reports is limited by variations in methodology and criteria for toxicity.

CONCLUSIONS

In vivo and in vitro studies on the environmental and biological effects of UV filters show a wide array of unanticipated adverse effects on the environment and exposed organisms. Coral bleaching receives considerable attention from the lay press, but the scientific literature identifies potential toxicities of endocrine, neurologic, neoplastic and developmental pathways. These effects harm a vast array of aquatic and marine biota, while almost no data supports human toxicity at currently used quantities (with the exception of contact allergy). Much of these data are from experimental studies or field observations; more controlled environmental studies and long-term human use data are limited. Several jurisdictions have prohibited specific UV filters, but this does not adequately address the dichotomy of the benefits of photoprotection vs lack of eco-friendly, safe, and FDA-approved alternatives.

Occurrence and Gas-Particle Partitioning of Organic UV-Filters in Urban Air

A retrospective analysis of a comprehensive series of high-volume air samples (n = 70) collected during 2010-2011 in Toronto (Canada) was performed. Seven UV compounds were analyzed by gas chromatography-tandem mass spectrometry (GC-MS/MS) with sum of concentrations (gas + particle phase) ranging from 80 to 2030 pg/m³. Homosalate (HMS) was the most prevalent organic UV-filter in air (47% of the total concentration), followed by 2-ethylhexyl salicylate (EHS, ∼29%), E- and Z-2-ethylhexyl 4-methoxycinnamate (EHMC, ∼17%). Ambient air (gas + particle phase) concentrations of organic UV-filters showed a strong seasonality, with peak levels during the summer. An analysis of Clausius-Clapeyron slopes indicated that much of the ambient burden of organic UV-filters are explained by volatilization from terrestrial and aquatic surfaces and supplemented with human activities and use of lotions and sunscreens, containing organic UV-filters, in addition to its use in plastics, textiles, paints, and pesticides. The results showed that organic UV-filters exist mainly in the gas phase with some exceptions, for instance, octocrylene (OCR), which was associated with both gas and particle phases, and avobenzone (AVB), which was predominantly in the particle phase. Lastly, this study revealed the need for basic physical chemical property data for organic UV-filters, including information on transformation rates and products, for better evaluating their environmental fate and effects.

Toxic effects and transcriptome analyses of zebrafish (Danio rerio) larvae exposed to benzophenones

Sunscreen chemicals, such as benzophenones (BPs), are common environmental contaminants that are posing a growing health concern due to their increasing presence in water, fish, and human systems. Benzoresorcinol (BP1), oxybenzone (BP3), and dioxybenzone (BP8) are the most commonly used BPs for their ability to protect from sunburn by absorbing a broad spectrum of ultraviolet radiation. In this study, zebrafish larvae were used as an in vivo model to investigate the potential risks and molecular mechanisms of the toxic effects of BPs. The effects of these BPs on the gene expression in the aryl hydrocarbon receptor pathway, estrogen receptor pathway, and sex differentiation were detected using quantitative real-time PCR. All BPs were found to function as agonists of the estrogen receptors α and β1, indicating that these BPs likely undergo similar molecular metabolism in vivo, whereby they can activate cytochrome P450 genes and promote the expression of CYP19A and DMRT1. Furthermore, the gene expression profile of larvae after BP3 exposure was evaluated using a whole transcriptome sequencing approach. BP3 affected estradiol biosynthesis and sex differentiation. It also regulated gonadotropin-releasing hormone, thus interfering with the endocrine system. As a xenobiotic toxicant, BP3 upregulated the expression of cytochrome P450 genes (CYP1A and CYP3A65) and glutathione metabolism-related genes (GSTA, GSTM, and GSTP). It also interfered with the nervous system by regulating the calcium signaling pathway. These findings will be useful for understanding the toxicity mechanisms and metabolism of BPs in aquatic organisms and promote the regulation of these chemicals in the environment.

Dispersive liquid-liquid microextraction (DLLME) and external real matrix calibration for the determination of the UV absorber 2-(2H-benzotriazol-2-yl)-4,6-di-tert-pentylphenol (UV 328) and its metabolites in human blood

2-(2H-Benzotriazol-2-yl)-4,6-di-tert-pentylphenol (UV 328; CAS: 25973-55-1) is a benzotriazole ultraviolet light (BUV) absorber which is applied to plastics and other organic substances to prevent discoloration and enhance product stability. Therefore, UV 328 is frequently used as a plastic additive and may lead to an exposure of consumers. For a reliable assessment of UV 328 metabolism, an analytical method applying dispersive liquid-liquid microextraction (DLLME) followed by gas chromatography tandem mass spectrometry and advanced electron ionization was developed which allows the determination of UV 328 and six of its metabolites in human whole blood. Sample preparation was optimized with respect to DLLME parameters. A critical aspect of the procedure was the application of spiked human blood for calibration, which proved to be essential for achieving accurate results. Validation of the method resulted in limits of detection of 0.1 μg/L for all analytes. Variation coefficients ranged from 2 to 9% for intraday precision and from 3 to 11% for interday precision. Furthermore, relative recovery rates between 80 and 100% were calculated. Afterwards, the procedure was successfully applied to blood samples collected from a volunteer orally exposed to a single dose of UV 328. The method proved to be highly sensitive, repeatable and robust for all compounds and may further be used for studies to elucidate the human metabolism and kinetics of UV 328 and for biomonitoring of specific, environmental and occupational exposure to this UV stabilizer.

Effect of the UV filter, Benzophenone-3, on biomarkers of the yellow clam (Amarilladesma mactroides) under different pH conditions

This work aimed to investigate effects of the ocean contamination by the sunscreen Benzophenone-3 (BP3) and acidification, caused by CO₂ enrichment, to the yellow clam, Amarilladesma mactroides. Biochemical biomarkers were analyzed in tissues (gills, digestive gland, and mantle) of clams exposed to the environmental concentration of 1 μg/L BP3, at seawater natural pH (pH 8.1) and at lower pH (pH 7.6). The tissues responded in different ways considering their physiological roles. In general, BP3 altered activity of the enzymes, glutathione-S-transferase (GST) and glutathione cysteine ligase (GCL); but mostly increased the level of glutathione (GSH). These effects were enhanced by acidification, without augmenting lipid peroxidation (LPO). Carbonic anhydrase activity (CA) increased after BP3 exposure in the digestive gland and decreased in the gills at pH 7.6, while Ca²⁺-ATPase activity was affected by acidification only. Changing levels of these enzymes can alter shell formation and affect the bivalve maintenance in impacted environments.

Assessing bioaccumulation potential of personal care, household and industrial products in a marine echinoderm (Holothuria tubulosa)

A bioaccumulation study of 16 emerging contaminants including preservatives, UV-filters, biocides, alkylphenols, anionic surfactants and plasticizers, in Holothuria tubulosa Gmelin, 1791 specimens was developed. Water and sediments from their coastal habitat were also analyzed. Sediment-water distribution coefficients (log Kd) were in the range 0.78 to 2.95. A rapid uptake and bioaccumulation of pollutants was found. Compounds were detected in intestine and gonads of H. tubulosa after only eight days of exposure. Field-based bioconcentration (BCF) and biota-sediment accumulation factors (BSAF) were calculated. Log BCF > 1 were obtained for most of the compounds studied, indicating their tendency to accumulate in tissue of H. Tubulosa. BCF values decrease as follow: Triclocarban > anionic surfactants > benzophenone 3 > non-ionic surfactants > bisphenol A > parabens. These data provide a detailed accounting of the distribution patterns of some emerging contaminants in organisms at the lower trophic level, representing a potential source of contaminants for organisms in higher levels of the food chain.

Food-Borne Exposure of Juvenile Rainbow Trout (Oncorhynchus mykiss) to Benzotriazole Ultraviolet Stabilizers Alone and in Mixture Induces Specific Transcriptional Changes

Benzotriazole ultraviolet-stabilizers (BZT-UVs) are commonly used as additives to protect from light-induced degradation in a variety of consumer goods. Despite their widespread presence in aquatic ecosystems, information on the effects of these compounds remains largely unknown. The objectives of the present study were to evaluate the chronic effects of 2 BZT-UVs alone and in a mixture, 2-(2H-benzotriazol-2-yl)-4,6-bis(1-methyl-1-phenylethyl)phenol (UV-234) and 2-(2H-benzotriazol-2-yl)-4,6-di-tert-pentylphenol (UV-328), in juvenile rainbow trout (Oncorhynchus mykiss) chronically exposed (for 28 d) through the diet. Chemical analyses of livers from exposed trout suggested liver accumulation and potential metabolism of the 2 compounds. Hepatic RNA-sequencing analyses revealed specific effects of each compound on gene transcription profiles; UV-234 affected mainly genes involved in cellular metabolism, whereas UV-328 induced the transcription of ribosomal proteins and downregulated genes involved in immune responses. Both compounds regulated iron homeostasis genes in an opposite manner. The mixture of both BZT-UVs did not produce significant evidence of additive or synergistic effects. Environ Toxicol Chem 2020;39:852-862. © 2020 Her Majesty the Queen in Right of Canada. Environmental Toxicology and Chemistry © 2020 SETAC.

Dietary Bioaccumulation and Biotransformation of Hydrophobic Organic Sunscreen Agents in Rainbow Trout

The present study investigated the dietary bioaccumulation and biotransformation of hydrophobic organic sunscreen agents, 2-ethylhexyl-4-methoxycinnamate (EHMC) and octocrylene (OCT), in rainbow trout using a modified Organisation for Economic Co-operation and Development 305 dietary bioaccumulation test that incorporated nonbiotransformed reference chemicals. Trout were exposed to 3 dietary concentrations of each chemical to investigate the relationship between dietary exposure concentration and observed accumulation and depuration. Both EHMC and OCT were significantly biotransformed, resulting in mean in vivo whole-body biotransformation rate constants (k_MET ) of 0.54 ± 0.06 and 0.09 ± 0.01 d^-1 , respectively. The k_MET values generated for both chemicals did not differ between dietary exposure concentrations, indicating that chemical concentrations in the fish were not high enough to saturate biotransformation enzymes. Both somatic and luminal biotransformation substantially reduce EHMC and OCT bioaccumulation potential in trout. Biomagnification factors (BMFs) and bioconcentration factors (BCFs) of EHMC averaged 0.0035 kg lipid kg lipid^-1 and 396 L kg^-1 , respectively, whereas those of OCT averaged 0.0084 kg lipid kg lipid^-1 and 1267 L kg^-1 . These values are 1 to 2 orders of magnitude lower than the BMFs and BCFs generated for reference chemicals of similar log K_OW . In addition, for both chemicals, derived BMFs and BCFs fell below established bioaccumulation criteria (1.0 kg lipid kg lipid^-1 and 2000 L kg^-1 , respectively), suggesting that EHMC ad OCT are unlikely to bioaccumulate to a high degree in aquatic biota. Environ Toxicol Chem 2020;39:574-586. © 2019 SETAC.

Tissue Distribution, Growth Dilution, and Species-Specific Bioaccumulation of Organic Ultraviolet Absorbents in Wildlife Freshwater Fish in the Pearl River Catchment, China

Tissue distributions and body-size dependent and species-specific bioaccumulation of 12 organic ultraviolet absorbents (UVAs) were investigated in 9 species of wildlife freshwater fish from the Pearl River catchment, South China. The concentrations of the 12 UVAs were from 109 to 2320 ng/g lipid weight in the fish tissue samples. The UVAs 2-hydroxy-4-methoxybenzophenone (BP-3), octocrylene (OCR), UV531, and 5 benzotriazole UV stabilizers (UVP, UV329, UV234, UV328, and UV327) were detected in more than half of the fish tissue samples. The UVA UV531 showed an obvious potential for bioaccumulation in the wild freshwater fish, with an estimated bioaccumulation factor (log BAF) and a biota-sediment accumulation factor (BSAF) of 4.54 ± 0.55 and 4.88 ± 6.78, respectively. Generally, liver (989 ± 464 ng/g lipid wt) contained the highest level of UVAs, followed in decreasing order by belly fat (599 ± 318 ng/g lipid wt), swimming bladder (494 ± 282 ng/g lipid wt), dorsal muscle (470 ± 240 ng/g lipid wt), and egg (442 ± 238 ng/g lipid wt). The bioaccumulation of UVAs in the freshwater wild fish was species specific and compound dependent. Bottom-dwelling detritus-ingesting omnivorous fish contained obviously higher UVA concentrations, suggesting that detritus/sediment ingestion is a significant pathway for exposure of the wild freshwater fish to the UVAs. The UVAs UV531 and BP-3 demonstrated a potential for growth dilution. Metabolism might play a significant role in elimination of the UVAs in the fish tissues, with the highest rate of metabolism in the liver. The UVAs did not demonstrate obvious trophic magnification in the freshwater ecosystem of the Pearl River catchment. More research is warranted to elucidate maternal transfer of the UVAs. Environ Toxicol Chem 2020;39:343-351. © 2019 SETAC.

Organic ultraviolet (UV) filters in the South China sea coastal region: Environmental occurrence, toxicological effects and risk assessment

Organic ultraviolet (UV) filters are common ingredients of personal care products and occur ubiquitously in the aquatic environment; however, little is known about their distribution in and potential effects to the marine environment. This study reports the occurrence, toxicological effects and risk assessment of eleven commonly consumed UV filters in marine surface water collected from the South China Sea (SCS) coastal region. The concentrations of UV filters ranged from <MDL to 145 ng/L in the SCS, in which benzophenone-3, octocrylene and butyl methoxydibenzoylmethane were the most dominant compounds with their detection frequencies over 97%. Relatively higher levels of total UV filters were found near the highly industrialized and urbanized Pearl River Estuary (PRE) and the concentrations gradually decreased towards the SCS. In general, the environmental levels of UV filters were higher at the western marine waters in Hong Kong than the eastern marine waters. Significant negative correlations were observed between benzophenone-4 and water temperature, as well as ethylhexyl methoxycinnamate and salinity (P < 0.001; r < -0.5). Immobilization test of barnacle nauplius larvae (Balanus amphitrite) was conducted to assess the acute toxicity of organic UV filters to marine organisms. Benzophenone-8 and 4-methylbenzylidene camphor showed relatively higher toxicity with the 50% effect concentrations (EC₅₀) of 2.2 and 3.9 mg/L, respectively. A preliminary risk assessment was conducted by the results obtained from our field and laboratory studies. Results showed that the risk to cause immobilization in barnacle nauplius larvae in associated with exposure to current levels of organic UV filters in the SCS was minimal.

Piece-by-piece analysis of additives and manufacturing byproducts in plastics ingested by seabirds: Implication for risk of exposure to seabirds

The risk of marine organisms ingesting plastics has become a growing concern due to hazard chemicals in plastics. To identify compounds to which seabirds potentially have substantial exposure, 194 plastics fragments and pellets ingested by seabirds, i.e., northern fulmars from the Faroe Islands, and laysan albatross and black-footed albatross from Mukojima Island, were analyzed piece by piece. Four kinds of UV stabilizers, 2 brominated flame retardants, and styrene oligomers were detected at detection frequencies of 4.6%, 2.1%, and 2.1%, respectively. Concentrations ranging from not detected (n.d.) - 1700 μg/g were measured for UV stabilizers, n.d. - 1100 μg/g for flame retardants, and n.d. - 3200 μg/g for styrene oligomers. We found that these chemicals could be retained in plastics during drifting and fragmentation in the ocean and transported to seabirds. This type of transport via plastics can be direct pathway that introduces hazardous compounds to marine organisms.

Predicting mercury bioavailability in soil for earthworm Eisenia fetida using the diffusive gradients in thin films technique

In general, the diffusive gradients in thin films (DGT) technique is an effective tool for evaluating metal bioavailability; however, its applicability is subject to the type of metal and organism involved. In this study, the accumulated masses of Hg in DGT probes and in the earthworm species Eisenia fetida were monitored for 10 days, to test if the DGT technique can be used as a predicting method for the bioavailability of soil Hg to earthworms. In the Hg exposure tests using soils prepared with different peat moss concentrations of 5, 10, 15, and 20% and varying pH values of 4.6, 5.6, and 6.2, the experimentally determined DGT-soil accumulation factor (DSAF) and biota-soil accumulation factor (BSAF) both increased as the peat moss content decreased and the pH increased. According to a one compartment model, this was a result of the increased Hg uptake rate constant (k₁) and the relatively stable Hg elimination constant (k₂) under lower peat moss and higher pH conditions. It is interesting to note that the Hg uptake rates by DGT and earthworms were considerably higher for fresh soils than for aged soils, while porewater (and acid-extractable) Hg concentrations were rather similar between the two types of soils. Across diverse soil properties, steady-state Hg in earthworm tissue showed a strong positive correlation with DGT-measured Hg flux ([earthworm Hg] = 354(DGT-Hg flux)-34, r² = 0.88), while meager correlations were found between Hg concentration in earthworms and that in porewater (and acid-extractable). The overall results indicate that DGT-measured Hg flux is a better tool than conventional methods for predicting Hg bioavailability for earthworms inhabiting diverse types of soil.

Occurrence and Species-Specific Distribution of Plastic Debris in Wild Freshwater Fish from the Pearl River Catchment, China

Freshwater systems are an important source and vector of plastic debris found in oceans. However, plastic debris in freshwater organisms has not been well studied. The occurrence, characterization, polymer composition, and seasonal and spatial distribution of plastic debris were investigated in 9 species of wild freshwater fish from the Pearl River catchment, south China. Approximately 50% of the total fish (n = 279) belonging to 9 species were found to ingest plastic debris with an average abundance of 7.0 ± 23.8 items/individual, indicating wide plastic contamination in the Pearl River catchment. Plastic debris were predominantly transparent or white in color, fibers or fragments in shape, and polyethylene, polypropylene, ethylene-propylene copolymer (PE-PP), and polyethylene terephthalate (PET) in polymer composition. A species-specific distribution of the plastic debris was observed in terms of abundance, shape, and polymer composition. Redbelly tilapia had the highest (27.4 ± 54.0 items/individual), whereas common carp had the lowest (0.2 ± 0.4 items/individual) abundance of the plastic debris in their gastrointestinal tracts. Fibers of PET were predominant in the freshwater species except in barbel chubs, which had mostly PE-PP fragments. Omnivores and bottom-dwellers were more likely to ingest plastic debris. Seasonal variation was observed, with generally higher abundance of plastic debris in fish collected in the dry season than in the wet season. Environ Toxicol Chem 2019;38:1504-1513. © 2019 SETAC.

Evaluation of the bioaccumulation of octocrylene after dietary and aqueous exposure

Octocrylene is used as UV filter in personal care products with a high production volume and can be detected in surface water and biota. It is liquid at ambient temperature, highly lipophilic, has a high adsorption capacity to organic material and is considered as persistent in the environment. The very low water solubility complicates the evaluation of potential long-term effects in aquatic toxicity testing, since effect thresholds are often above the water solubility limit. Thus, the evaluation of the bioaccumulation potential becomes highly relevant for the assessment of long-term environmental effects. However, even the determination of the water solubility limit for a substance with such difficult properties is challenging. The following experiments are described, and results compared to available environmental monitoring data: A bioconcentration study with aqueous exposure (BCF) in zebrafish and a biomagnification study with dietary exposure (BMF) in rainbow trout, as well as supporting experiments to evaluate the water solubility. The growth and lipid corrected BCF determined by aqueous exposure was 858 L kg^-1 while the corrected BMF was 0.0335. The model-based estimation of the BCF from BMF (152-1182 L kg^-1) is in good agreement with the measured BCF value. Environmental monitoring data provide only limited information on the bioaccumulation potential of octocrylene, as only few investigations were made in biota and water in parallel and concentrations of octocrylene vary by several orders of magnitude during seasons. Based on the determined fish BCF data, we conclude that OCR is not bioaccumulative according to the criteria as laid down by ECHA, 2017. Furthermore, the low BMF value indicates no accumulation along the food chain.

Occurrence of substituted diphenylamine antioxidants and benzotriazole UV stabilizers in Arctic seabirds and seals

Substituted diphenylamine antioxidants (SDPAs) and benzotriazole UV stabilizers (BZT-UVs) are contaminants of emerging environmental concern. However, little is known about the occurrence of these contaminants in the Arctic. In this study, we investigated the levels of 11 SDPAs and 6 BZT-UVs in livers and eggs of two seabird species, the black-legged kittiwake (Rissa tridactyla) and northern fulmar (Fulmarus glacialis), as well as the liver of ringed seals (Pusa hispida) from Canadian high- and sub-Arctic sites. The concentrations of ΣSDPAs in seabird livers (median 336 pg g^-1, wet weight (ww)) were significantly higher than the eggs (median 24 pg g^-1, ww) and the seal livers (median 38 pg g^-1, ww), suggesting liver was a primary tissue of SDPA accumulation in seabirds and that seabirds were at greater risk of exposure to SDPAs than marine mammals in the Arctic. The predominant SDPA was monostyryl octyl-diphenylamine and this compound was detected in every seabird and seal sample, indicating the widespread distribution of this contaminant in Arctic food webs. Unlike SDPAs, the detection rate and concentrations of BZT-UVs in seals were higher than in seabirds. The compound 2-(2H-benzotriazol-2-yl)-4-(1,1,3,3-tetramethylbutyl)phenol (UV329) or its isomer 2-(2H-benzotriazol-2-yl)-4-(tert-butyl)-6-(sec-butyl) phenol (UV350) was the predominant BZT-UVs in seals, with the concentrations of ΣBZT-UVs between <method quantification limits and 1.66 × 10⁴ pg g^-1 (ww) (median: 2.36 × 10³ pg g^-1, ww). This is the first report of the different distribution patterns of SDPAs and BZT-UVs in wildlife from Canadian Arctic sites.

Massive coastal tourism influx to the Mediterranean Sea: The environmental risk of sunscreens

The Mediterranean region is, by far, the leading tourism destination in the world, receiving more than 330 million tourists in 2016. This tourism is undertaken mostly for seaside holidays, and during the summer season concentrates between 46% and 69% of the total international arrivals; this is equivalent to a density of 2.9 tourists per meter of Mediterranean coast, or double this number taking into account the local/permanent population in addition. Previous studies have reported not only the presence of sunscreen in the various environmental compartments (water, sediments and biota) of the Mediterranean Sea (MS) and other regions, but also show that sunscreen products are toxic for marine biota and are accumulated and biomagnificated. Here, we highlight that the environmental risk of these chemicals is likely to be exacerbated in the MS due to the massive influx of tourists and its densely populated coasts, the basin's limited exchanges with the ocean, the high residence time of surface waters, and its oligotrophic waters.

Concentrations and tissue-specific distributions of organic ultraviolet absorbents in wild fish from a large subtropical lake in China

Organic ultraviolet absorbents (UVAs) have been detected in various materials and biota, but little is known about the distributions of UVAs in the tissues of biota. In this study, tissue-specific UVA accumulation in six fish species from Lake Chaohu, China, was investigated. The sums of 12 UVA concentrations in muscles, gills, and livers were 7.65-120, 10.1-281, and 26.4-359 ng/g dry weight, respectively. Ethylhexyl methoxycinnamate, 4-methylbenzylidene-camphor, and 2-(2'-hydroxy-3',5'-di-tert-butylphenyl)-5-chlorobenzotriazole were the dominant UVAs. Ethylhexyl salicylate and homosalate have been found in the aquatic species firstly. UVAs were taken up to different degrees by different fish species. The UVA muscle bioconcentration factors were lower than predicted by the Estimation Programs Interface Suite model, suggesting that such models may overestimate UVA accumulation in fish. The tissue distribution patterns indicated that UVAs are easily transferred to the muscles after being absorbed through the gills. The liver was found to preferentially accumulate UVAs and have a high UVA accumulation capacity, implying liver damage may be caused by UVAs. This is the first time the partitioning of UVAs between the liver, muscle, and gills of freshwater fish has been studied. The data acquired will improve our understanding of the pharmacokinetics and toxicities of UVAs in aquatic organisms.

Environmental occurrence and hazard of organic UV stabilizers and UV filters in the sediment of European North and Baltic Seas

UV absorbing compounds are of emerging concern due to their large production volumes, their persistence or pseudo-persistence, and their potential adverse effects. This is the first study investigating the environmental occurrence and potential hazard of organic UV stabilizers and UV filters in the North and Baltic Sea surface sediments, including the connecting Skagerrak and Kattegat straits. In total, nineteen substances were identified over the entire study area, including the rarely studied compounds ethylhexyl triazone (EHT) and bisoctrizole (UV-360). Octocrylene (OC) was the predominant compound in this study with regard to detection frequency (79%) and concentrations (up to 9.7 ng/g dw). OC accounted for more than 65% of UV stabilizer contamination in the German Bight. The triazine derivative EHT was quantified in the Rhine-Meuse-Delta and the German Bight in concentrations up to 2.0 ng/g dw. In the Baltic Sea, benzotriazole UV stabilizers accounted for 60% of the contamination, with UV-360 as the main substance. The estimated environmental hazard quotients indicated a negligible impact on benthic and sediment-dwelling organisms in the North and Baltic Seas. Region-specific contamination pattern and riverine influences were revealed. The results suggest that both direct and indirect sources contribute to the UV stabilizer and UV filter contamination in the study area.

Occurrence, distribution and ecological risk of ultraviolet absorbents in water and sediment from Lake Chaohu and its inflowing rivers, China

The available information is insufficient to enable a reliable understanding of the global distribution and effect of organic ultraviolet absorbents (UVAs) on ecosystems. Little is known about the pollution of China's lakes by these chemicals. We conducted a survey of UVAs in water and sediment from Lake Chaohu and its inflowing rivers. The UVAs were widely present in this area and the concentrations of total 12 UVAs (Σ₁₂ UVAs) ranged between 162 and 587 ng/L in water and 9.70-178 ng/g in sediment. Benzophenone and benzophenone-3 were dominant in water, and benzophenone and octocrylene dominated in sediment. Higher concentrations of benzophenone were detected in the investigated water samples, although the contamination levels of UVAs in this study were comparable to those investigated in other areas. In addition to the inputs from the UVAs used as filters in cosmetics, the discharge from industries using UVAs as stabilizers also contributed much to the pollution in the study waters. Generally, the risk to aquatic organisms from exposure to UVAs in this area was low, but further research is needed to elucidate the fate of UVAs and to understand bioaccumulation and associated risks.

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.

Body size-dependent bioaccumulation, tissue distribution, and trophic and maternal transfer of phenolic endocrine-disrupting contaminants in a freshwater ecosystem

Parabens, bisphenol A (BPA), triclosan, and triclocarban are recognized endocrine-disrupting contaminants (EDCs); and their occurrence in the environment has attracted increasing concern. Body size-dependent bioaccumulation, tissue distribution, trophic magnification, and maternal transfer of methyl-, ethyl-, propyl-, and butylparabens; 2-phenylphenol (PHP); BPA; triclosan; and triclocarban were investigated in freshwater fish of the Pearl River catchment, China. Most of the EDCs were detected in more than half of the biota samples, ranging from not detected to 6750 ng g^-1 lipid weight, with median concentrations of 5 to 72 ng g^-1 lipid weight. Livers generally contained the highest EDC levels (1609 ± 1860 ng g^-1 lipid wt, mean ± standard deviation), followed in decreasing order by eggs (842 ± 1317 ng g^-1 lipid wt), belly fats (488 ± 465 ng g^-1 lipid wt), and dorsal muscles (240 ± 239 ng g^-1 lipid wt) of the wildlife. Body size-dependent bioaccumulation of the EDCs was observed in the freshwater fish, which varied according to species, tissue, and compound. The concentrations of triclosan, PHP, and BPA usually showed decreasing trends, whereas parabens mostly demonstrated increasing tendency with increasing fish weights, indicating effects of growth dilution and bioaccumulation, respectively. Potential biomagnification was shown by triclosan with trophic magnification factors of 3.0, 4.3, and 4.0 in liver, belly fat, and dorsal muscle, respectively. In addition, the potential of maternal transfer in the fish was primarily revealed for methyl- and propylparabens, PHP, triclosan, and BPA. Presence of the EDCs in the freshwater organisms of the Pearl River catchment warrants more attention considering the potential of trophic magnification and maternal transfer. Environ Toxicol Chem 2018;37:1811-1823. © 2018 SETAC.

Environmental effects of ozone depletion, UV radiation and interactions with climate change: UNEP Environmental Effects Assessment Panel, update 2017

The Environmental Effects Assessment Panel (EEAP) is one of three Panels of experts that inform the Parties to the Montreal Protocol. The EEAP focuses on the effects of UV radiation on human health, terrestrial and aquatic ecosystems, air quality, and materials, as well as on the interactive effects of UV radiation and global climate change. When considering the effects of climate change, it has become clear that processes resulting in changes in stratospheric ozone are more complex than previously held. Because of the Montreal Protocol, there are now indications of the beginnings of a recovery of stratospheric ozone, although the time required to reach levels like those before the 1960s is still uncertain, particularly as the effects of stratospheric ozone on climate change and vice versa, are not yet fully understood. Some regions will likely receive enhanced levels of UV radiation, while other areas will likely experience a reduction in UV radiation as ozone- and climate-driven changes affect the amounts of UV radiation reaching the Earth's surface. Like the other Panels, the EEAP produces detailed Quadrennial Reports every four years; the most recent was published as a series of seven papers in 2015 (Photochem. Photobiol. Sci., 2015, 14, 1-184). In the years in between, the EEAP produces less detailed and shorter Update Reports of recent and relevant scientific findings. The most recent of these was for 2016 (Photochem. Photobiol. Sci., 2017, 16, 107-145). The present 2017 Update Report assesses some of the highlights and new insights about the interactive nature of the direct and indirect effects of UV radiation, atmospheric processes, and climate change. A full 2018 Quadrennial Assessment, will be made available in 2018/2019.

Bioaccumulation and trophic transfer of metals, As and Se through a freshwater food web affected by antrophic pollution in Córdoba, Argentina

The concentration of metals (Al, Cr, Mn, Fe, Ni, Cu, Zn, Ag, Cd, Hg, Pb, U), As and Se in different ecosystem components (water, sediment, plankton, shrimp, and fish muscle) has been determined in a eutrophic reservoir in the Province of Córdoba (Argentina). Los Molinos Lake (LML) was sampled during the dry (DS) and wet seasons (WS) in order to examine the bioaccumulation and transfer of these inorganic elements through the food web. Stable nitrogen isotope (δ¹⁵N) was used to investigate trophic interactions. According to this, samples were divided into three categories: plankton, shrimp (Palaemonetes argentinus) and fish (Silverside, Odontesthes bonariensis). The bioaccumulation factor (BAF) was calculated for the organisms, and it was determined that the elements analyzed undergo bioaccumulation, especially in organisms such as plankton. The invertebrates were characterized by the highest BAF for Cu and Zn in both seasons, As (DS), and Cd and Hg (WS). The fish muscle was characterized by the highest BAF for Se (WS), Ag and Hg (DS). On the other hand, a significant decrease in Al, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Cd and U concentrations through the analyzed trophic web during both seasons was observed. Moreover, a significant increase in Hg levels was observed with increasing trophic levels in the DS, indicating its biomagnification. Despite the increasing impact of metals, As and Se pollution in the studied area due to urban growth and agricultural and livestock activities, no previous study has focused on the behavior and relationships of these pollutants with the biotic and abiotic components of this aquatic reservoir. We expect that these findings may be used for providing directions or guidance for future monitoring and environmental protection policies.