Photochemical response of the scleractinian coral Stylophora pistillata to some sunscreen ingredients

Abstract

Ultraviolet (UV) filters and preservatives, which are common constituents of sunscreens and other cosmetics, are reported as a threat for coastal coral reef ecosystems; however, few studies have assessed the effects of these compounds on coral health. This study presents the chronic effects (of measured, long-term and low concentrations) of some preservatives (ethylparaben, butylparaben), mineral UV filter (zinc oxide, ZnO) and organic UV filters (terephthalylidene dicamphor sulfonic acid, drometrizole trisiloxane, ethylhexyltriazone, butylmethoxydibenzoylmethane and 2-ethylhexyl 2-cyano-3,3diphenylacrylate) on the maximal photosynthetic efficiency (F v /F m) of the symbionts associated with the scleractinian coral Stylophora pistillata. It first shows that for many organic filters, measured concentrations were significantly lower than nominal concentrations, due to the lipophilic nature of the compounds. In addition, the F v /F m was more sensitive to ZnO than all other sunscreen ingredients, with exposure to 90 lg L-1 ZnO for 35 d, reducing F v /F m by 38% compared with controls. The other UV filters tested showed no adverse effect on coral symbionts or animal tissue up to the concentration corresponding to their water solubility limit (and even above). Similarly, no adverse effect was observed in our conditions with the preservative ethylparaben, but the preservative butylparaben decreased the F v /F m by 25% at the highest concentration of 100 lg L-1. None of the sunscreen ingredients were as toxic to corals as the reference pollutants tributyltin, diuron and monuron, which significantly inhibited F v /F m at 10, 1 and 0.1 lg L-1 , respectively. Overall, this study highlights the need to improve our knowledge on the in situ concentrations of UV filters and preservatives as well as their individual and combined effects on corals.

Aqueous aging of a silica coated TiO2 UV filter used in sunscreens: investigations at the molecular scale with dynamic nuclear polarization NMR

“…The SiO 2 coating protects the consumer from TiO 2 driven photoreactivity, however the present data show that upon release into the aqueous environment this protective coating disappears, exposing the bare TiO 2 core and possibly resulting in detrimental environmental effects against several types of biota, including coral reefs. [14][15][16][17][18][19] Indeed, although the nanocomposite is included within an organic formulation in the nal sunscreen product, the organic matrix has a limited lifetime and in some cases may detach from the mineral composite aer periods of as short as 24 h, 21,35 exposing the SiO 2 and allowing dissolution to proceed from that point on.…”

“…[14][15][16][17] including the coral reefs that they are supposed to help preserve. 18,19 As a matter of fact, the apparent safety of mineral UV lters is intimately linked to the presence of coatings around the core of these particles. This is especially true for TiO 2 , because of its marked photocatalytic properties, which contribute to most of the potential adverse effects of this material.…”

Assessing Sunscreen Lifecycle to Minimize Environmental Risk Posed by Nanoparticulate UV-Filters – A Review for Safer-by-Design Products

“…The UV-filters can be organic or mineral in nature, and provide the desired solar protection factor (SPF) that is labeled on the product packaging (Steinberg, 2007). Some organic UV-filters found in many sunscreens have been blamed for having endocrine disrupting capacities inducing adverse effects on fecundity and reproduction (Schlumpf et al, 2004;Kunz and Fent, 2006;Calafat et al, 2008;Bluthgen et al, 2012), as well as causing adverse effects on marine systems (Calafat et al, 2008;Danovaro et al, 2008;Kunz and Fent, 2009;Sanchez-Quiles and Tovar-Sanchez, 2014;Downs et al, 2016;Sendra et al, 2017;Fel et al, 2019;Rodriguez-Romero et al, 2019;Tovar-Sanchez et al, 2019). While mineral UVfilters may offer an alternative to synthetic organic UV-filters, their toxicity, fate, and overall impact on the environment are still under consideration, and their resulting acceptance by the consumers is largely related to the potential risks of nanotechnology-based products.…”

The World Coral Conservatory (WCC): A Noah's ark for corals to support survival of reef ecosystems

“…• Biomedical and cosmetic applications: corals offer very interesting aspects concerning aging and regeneration, for which the sequencing of 1,000 transcriptomes will improve our knowledge regarding candidate genes contributing to longevity and the extraordinary resistance to UV exposure. Further, corals can become ecological sentinels, and tests using coral cultures can become an industrial standard of ecotoxicity for cosmetics and other xenobiotics [71];…”