Coral Ecotoxicological Data Evaluation for the Environmental Safety Assessment of Ultraviolet Filters

Abstract

There is growing interest in the environmental safety of ultraviolet (UV) filters found in cosmetic and personal care products (CPCPs). The CPCP industry is assessing appropriate environmental risk assessment (ERA) methods to conduct robust environmental safety assessments for these ingredients. Relevant and reliable data are needed for ERA, particularly when the assessment is supporting regulatory decision‐making. In the present study, we apply a data evaluation approach to incorporate nonstandard toxicity data into the ERA process through an expanded range of reliability scores over commonly used approaches (e.g., Klimisch scores). The method employs an upfront screening followed by a data quality assessment based largely on the Criteria for Reporting and Evaluating Ecotoxicity Data (CRED) approach. The method was applied in a coral case study in which UV filter toxicity data was evaluated to identify data points potentially suitable for higher tier and/or regulatory ERA. This is an optimal case study because there are no standard coral toxicity test methods, and UV filter bans are being enacted based on findings reported in the current peer‐reviewed data set. Eight studies comprising nine assays were identified; four of the assays did not pass the initial screening assessment. None of the remaining five assays received a high enough reliability score ( R n ) to be considered of decision‐making quality (i.e., R1 or R2). Four assays were suitable for a preliminary ERA (i.e., R3 or R4), and one assay was not reliable (i.e., R6). These results highlight a need for higher quality coral toxicity studies, potentially through the development of standard test protocols, to generate reliable toxicity endpoints. These data can then be used for ERA to inform environmental protection and sustainability decision‐making. Environ Toxicol Chem 2021;40:3441–3464. © 2021 Personal Care Products Council. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

Towards the Development of Standardized Bioassays for Corals: Acute Toxicity of the UV Filter Benzophenone-3 to Scleractinian Coral Larvae

“…Downs et al [ 36 ] studied mortality and also deformation as sublethal endpoint in Stylophora pistillata planulae after exposure to BP3. However, the ecological relevance of sublethal effects of such morphological changes in planulae are yet to be demonstrated [ 52 ]. Compared to other acute coral larvae toxicity studies [ 67 , 87 , 88 ], which used a period of 24 h to investigate settlement in A. tenuis planulae, we chose a test duration of 48 h. This was due to the circumstance that for the species we tested, a 24 h period was insufficient to achieve ≥70% settlement (metamorphosis and attachment) within the negative control (data not shown), which is in agreement with previous settlement studies [ 73 , 89 , 90 ].…”

“…While most UV filter coral toxicity studies so far have not run positive controls with their experiments [ 49 , 50 , 52 ], we have included TBTO as a reference toxicant. However, we recommend using alternative reference toxicants as positive controls in future studies so that settlement inhibition can be induced besides mortality, and also due to TBTO’s toxicity towards humans [ 71 ].…”

“…23 [ 75 ], and additionally missing negative controls (only solvent controls were included). Wijgerde et al [ 46 ] used 0.01% DMSO; however, as only a solvent control was included (no negative medium control), observed effects in that control (33% mortality) made the study results unreliable [ 50 , 52 ]. Despite that, even if the solvent concentration is well below the maximum recommended level (0.01%; [ 75 ]), secondary effects cannot be ruled out since there is a paucity of studies assessing solvent effects on corals.…”

“…Quantitative comparisons with previous studies are difficult due to methodological and analytical inconsistencies, and due to the lack of analytical verification of exposure concentration in various previous studies as discussed in recent literature [ 49 , 50 , 51 , 52 ]. Up to this date, only two other studies performed toxicity assays with UV filters on coral larvae.…”

“…Based on these studies, policymakers in various locations (i.e., Hawaii, US Virgin Islands, Palau, Aruba and Bonaire) have already taken regulatory actions and banned the use of some organic UV filters including BP3, ethylhexyl methoxycinnamate (EHMC or octinoxate), octocrylene (OCR) and 4-methylbenzylidene camphor (4MBC) in sunscreens [ 49 , 50 , 51 ]. Those bans, however, are controversial as the underlying studies revealed several shortcomings (e.g., lack of analytical verification of exposure concentrations, inadequate controls, lack of environmental relevance) that question the reliability of some of the test results and the conclusions drawn within these studies [ 49 , 50 , 51 , 52 ]. Several recent review articles have compiled a comprehensive overview about the current status of coral toxicity research on UV filters and their shortcomings [ 48 , 49 , 51 ].…”