Octocrylene (OC) is an ingredient used in many sunscreens and cosmetics worldwide. Our group evaluated the toxicity of OC in corals. Adult Pocillopora damicornis coral was treated with OC at concentrations of 5, 50, 300 and 1000 µg/L. Most polyps were closed at concentrations of 300 µg/L and higher. Further, metabolomic profiling provided crucial information regarding OC accumulation in coral tissues and OC toxicity. First, we demonstrated that OC was transformed into fatty acid conjugates via oxidation of the ethylhexyl chain, yielding very lipophilic OC analogs that accumulate in coral tissues. Second, the differential analysis of coral profiles revealed higher levels of 15 acylcarnitines, suggesting abnormal fatty-acid metabolism related to mitochondrial dysfunction. The formation of OC analogs suggests that OC concentrations measured in the environment and organisms may have been largely underestimated. Overall, these results call for an in-depth evaluation of OC toxicity and the reevaluation of the actual OC accumulation rate in the ocean's food chain, including OC-fatty acid conjugates. FOR TOC ONLY

Metabolomic profiling of the hexacoral Pocillopora damicornis exposed to solar filters revealed a metabolomic signature of stress in this coral. It was demonstrated that the concentration of the known steroid (3β, 5α, 8α)-5, 8-epidioxy-ergosta-6, 24(28)-dien-3-ol (14) increased in response to octocrylene (OC) and ethylhexyl salicylate (ES) at 50 µg/L. Based on the overall coral response, we hypothesize that steroid 14 mediates coral response to stress. OC also specifically altered mitochondrial function at this concentration and above, while ES triggered a stress/inflammatory response at 300 µg/L and above as witnessed by the significant increases in the concentrations of polyunsaturated fatty acids, lysophosphatidylcholines and lysophosphatidylethanolamines. Benzophenone-3 increased the concentration of compound 14 at 2 mg/L, while the concentration of stress marker remained unchanged upon exposition to the other solar filters tested. Also, our results seemed to refute earlier suggestions that platelet-activating factor is involved in the coral inflammatory response. Coral reefs are experiencing an unprecedented planet-wide decline 1. This decline has been attributed to several anthropogenic factors, including global warming, overfishing, and pollution. Widely used for skin protection against cancer, solar filters are regularly released in the sea from populated coastal zones or in sites dedicated to touristic activities including a bathing zone. Nonetheless, the impacts of solar filters on corals have been relatively understudied to date. An early article from Danovaro and coworkers 2 demonstrated that solar filters can induce coral bleaching by promoting viral infections. More recently, it was shown that several UV filters in the benzophenone class, along with octocrylene (OC), exert direct detrimental effects on corals 3-7. Additionally, it has been shown that other ingredients in sunscreens and cosmetics exacerbate the toxicity of the UV filters OC and octinoxate 8 , while Fel et al. reported that many UV filters, including OC have little or no effect on corals 9. According to Downs et al., benzophenone-3 (BP3) induced concentration-dependent planulae coral bleaching, DNA-AP lesions, ossification of the planula, and planulae mortality, and these adverse effects were exacerbated by light 3. In our previous work, we compared the metabolomic profiles of exposed and unexposed corals and demonstrated that OC triggers mitochondrial dysfunction that results in the accumulation of acylcarnitines 7. Also of great concern were both the accumulation of OC derivatives in coral tissues and the concentration at which the toxicity was detected. In a 1-week exposure experiment, 19 OC derivatives were found in the coral tissue, and the response-inducing concentration was 50 µg/L, a concentration only 5 to 10 times higher than the highest environmental concentrations reported in the literature 10,11. Since wild corals are exposed to solar filters for longer periods of time, it has been hypothesized that OC does impact corals ...

The presence of pharmaceutical and personal care product (PPCP) residues in the aquatic environment is an emerging issue due to their uncontrolled release through gray water, and accumulation in the environment that may affect living organisms, ecosystems and public health. The aim of this study is to assess the toxicity of benzophenone-3 (BP-3), bis-ethylhexyloxyphenol methoxyphenyl triazine (BEMT), butyl methoxydibenzoylmethane (BM), methylene bis-benzotriazolyl tetramethylbutylphenol (MBBT), 2-ethylhexyl salicylate (ES), diethylaminohydroxybenzoyl hexyl benzoate (DHHB), diethylhexyl butamido triazone (DBT), ethylhexyl triazone (ET), homosalate (HS) and octocrylene (OC) on marine organisms from two major trophic levels, including autotrophs (Tetraselmis sp.) and heterotrophs (Artemia salina). In general, results showed that both HS and OC were the most toxic UV filters for our tested species, followed by a significant effect of BM on Artemia salina due to BM—but only at high concentrations (1 mg/L). ES, BP3 and DHHB affected the metabolic activity of the microalgae at 100 µg/L. BEMT, DBT, ET, MBBT had no effect on the tested organisms, even at high concentrations (2 mg/L). OC toxicity represents a risk for those species, since concentrations used in this study are 15–90 times greater than those reported in occurrence studies for aquatic environments. For the first time in the literature, we report HS toxicity on a microalgae species at concentrations complementing those found in aquatic environments. These preliminary results could represent a risk in the future if concentrations of OC and HS continue to increase.

Organic UV filters are continuously released in aquatic ecosystems due to their widespread use, especially in touristic coastal environments. Generally, organic UV filters are poorly soluble in water and tend to accumulate in the sediment compartment. This represents a conceivable risk for sediment-dwelling organisms and a potential for transfer of the UV filters up the food chain. This study aimed to assess the potential transfer of seven UV filters including benzophenone-3 (BP3), bis-ethylhexyloxyphenol methoxyphenyl triazine (BEMT), butyl methoxydibenzoylmethane (BM), methylene bis-benzotriazolyl tetramethylbutylphenol (MBBT), 2-ethylhexyl salicylate (ES), diethylhexyl butamido triazone (DBT), and octocrylene (OC) from artificial spiked sediment (10 µg·g−1 dry weight) to sediment-dwelling worms. All UV filters were detected in the worms after 28 days of exposure, but only BP3 was apparently bioaccumulated, with a biota sediment accumulation factor (BSAF) of 12.38 ± 4.65. However, metabolomic profiling revealed that OC was metabolized by the worms into 11 fatty acid conjugates, demonstrating that OC did also accumulate in the worms in the form of OC–fatty acid conjugates. Here, the sole quantification of the parent organic UV filter underestimated the accumulation factor and the exposure of organisms. In general, it is therefore important to pair the conventional method (BSAF calculus) with other techniques, such as metabolomics, to assess the actual potential for bioaccumulation of xenobiotics including transformed xenobiotics.

The environmental fate and behavior of nanoplastics (NPs) and their toxicity against aquatic organisms are under current investigation. In this work, relevant physicochemical characterizations were provided to analyze the ecotoxicological risk of NPs in the aquatic compartment. For this purpose, heteroaggregates of 50 nm polystyrene nanospheres and natural organic matter were prepared and characterized. The kinetic of aggregation was assimilated to a reaction-limited colloid aggregation mode and led to the formation of heteroaggregates in the range of 100–500 nm. Toxicities of these heteroaggregates and polystyrene nanospheres (50 and 350 nm) were assessed for a large range of concentrations using four benthic and one planktonic algal species, in regards to particle states in the media. Heteroaggregates and nanospheres were shown to be stable in the exposure media during the ecotoxity tests. The algal species exhibited very low sensitivity (growth and photosynthetic activity), with the noteworthy exception of the planktonic alga, whose growth increased by more than 150% with the heteroaggregates at 1 µg L−1. Despite the lack of a strong direct effect of the NPs, they may still impair the functioning of aquatic ecosystems by destabilizing the competitive interactions between species. Moreover, further work should assess the toxicity of NPs associated with other substances (adsorbed pollutants or additives) that could enhance the NP effects.

Due to their various properties as polymeric materials, plastics have been produced, used and ultimately discharged into the environment. Although some studies have shown their negative impacts on the marine environment, the effects of plastics on freshwater organisms are still poorly studied, while they could be widely in contact with this pollution. The current work aimed to better elucidate the impact and the toxicity mechanisms of two kinds of commercial functionalized nanoplastics, i.e., carboxylated polystyrene microspheres of, respectively, 350 and 50 nm (PS350 and PS50), and heteroaggregated PS50 with humic acid with an apparent size of 350 nm (PSHA), all used at environmental concentrations (0.1 to 100 µg L−1). For this purpose, two relevant biological and aquatic models—amphibian larvae, Xenopus laevis, and dipters, Chironomus riparius—were used under normalized exposure conditions. The acute, chronic, and genetic toxicity parameters were examined and discussed with regard to the fundamental characterization in media exposures and, especially, the aggregation state of the nanoplastics. The size of PS350 and PSHA remained similar in the Xenopus and Chironomus exposure media. Inversely, PS50 aggregated in both exposition media and finally appeared to be micrometric during the exposition tests. Interestingly, this work highlighted that PS350 has no significant effect on the tested species, while PS50 is the most prone to alter the growth of Xenopus but not of Chironomus. Finally, PSHA induced a significant genotoxicity in Xenopus.

The presence of pharmaceutical and personal care products' (PPCPs) residues in the aquatic environment is an emerging issue due to their uncontrolled release, through grey water, and accumulation in the environment that may affect living organisms, ecosystems and public health.The aim of this study is to assess the toxicity of benzophenone-3 (BP-3), bis-ethylhexyloxyphenol methoxyphenyl triazine (BEMT), butyl methoxydibenzoylmethane (BM), methylene bisbenzotriazolyl tetramethylbutylphenol (MBBT), 2-Ethylhexyl salicylate (ES), diethylaminohydroxybenzoyl hexyl benzoate (DHHB), diethylhexyl butamido triazone (DBT), ethylhexyl triazone (ET), homosalate (HS), and octocrylene (OC) to marine organisms from two major trophic levels including autotrophs (Tetraselmis sp.) and heterotrophs (Artemia salina). In general, EC50 results show that both HS and OC are the most toxic for our tested species, followed by a significant effect of BM on Artemia salina but only at high concentrations (1 mg/L) and then an effect of ES, BP3 and DHHB on the metabolic activity of the microalgae at 100 µg/L. BEMT, DBT, ET, MBBT had no effect on the tested organisms, even at high concentrations (2mg/L). OC toxicity represent a risk for those species since it is observed at concentrations only 15 to 90 times 2 higher than the highest concentrations reported in the natural environment and HS toxicity is for the first time reported on microalgae and was very important on Tetraselmis sp. at concentrations close to the natural environment concentrations. Keywords UV-filtersToxicity tests Marine microalgae Artemia salinaMarine environment Instar II III) was determined after 48 h of exposure by counting dead larvae (Fig. 1). At the highest 130 8 concentration tested (2 mg/L), HS, BM, and OC demonstrated a significant effect on Nauplii 131 survival (p < 0.05) with mortality values reaching 54 ± 16%, 64 ± 19% and 88 ± 16%, respectively. 132 At lower concentrations of these filters no significant effect was detected. For BP3, BEMT, MBBT, 133 ES, DHHB, DBT and ET no toxicity was observed, even at the highest concentration. 134 135 136 137

The objective of this work was to study the effect of octocrylene on Stylophora pistillata and to compare the metabolomic response of this coral species to that obtained with Pocillopora damicornis. When S. pistillata coral was exposed to octocrylene, it accumulated octocrylene derivatives similar to P. damicornis. Octocrylene−fatty acid conjugates were found, as well as octocrylene heterosides. Furthermore, the tissue concentrations of various acylcarnitines and three sphingoid bases increased significantly. This phenomenon was indicative of mitochondrial dysfunction and the induction of cellular senescence processes in exposed corals. Overall, the responses of the two corals to octocrylene pollution were consistent. The proven impact of octocrylene on a second coral species suggests that potential environmental octocrylene pollution could impact many reef-building species. Furthermore, this work demonstrates that octocrylene may be modified in vivo by many organisms and that levels of octocrylene contamination in the food chain have probably been underestimated until now.