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Coral reefs are globally declining due to various anthropogenic stressors. Amongst those, chemical pollutants, such as pesticides from agricultural runoff, sewage or an overabundance of personal care products in coastal waters due to intense tourism, may be considered as a local stressor for reef-building corals. The extent to which such chemicals exhibit toxic effects towards corals at environmentally relevant concentrations is currently controversially discussed and existing studies are often based on varying and sometimes deficient test methods. To address this uncertainty, we adapted available methods into a reliable and comprehensive acute coral toxicity test method for the reef-building coral Montipora digitata. The toxicities of the four substances benzophenone-3 (BP-3), Diuron (DCMU), copper (Cu2+ as CuCl2, positive control) and dimethylformamide (DMF, solvent) were assessed in a 96 h semi-static test design. Endpoints such as maximum quantum yield, bleaching, tissue loss and mortality were evaluated with respect to their suitability for regulatory purposes. Overall, the endpoints bleaching and mortality yielded sensitive and robust results for the four tested substances. As the test method follows the principles of internationally standardized testing methods (ISO, OECD), it can be considered suitable for further validation and standardization. Once validated, a standardized test method will help to obtain reproducible toxicity results useful for marine hazard and risk assessment and regulatory decision making. [ABSTRACT FROM AUTHOR]

Objective: The aim of this work was to review the principals of environmental hazard and risk assessment (ERA) of cosmetic UV filters registered under EU REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals). Furthermore, effects as obtained from non‐standardized testing methods and organisms from scientific literature were compared against the predicted no effect concentrations (PNECs) as derived based on standardized test methods for the various environmental compartments under REACH. Methods: The REACH dossiers at the ECHA webpage were screened for available information related to basic physico–chemical data (i.e. water solubility, octanol–water partitioning coefficient), PNECs and associated data (data basis, assessment factors (AFs)). Scientific literature was screened for available ecotoxicity data and the adverse effect levels were compared against the derived PNECs under REACH. Current approaches for environmental risk assessments of UV filters were evaluated for its applicability for a direct release scenario. Results: Under REACH, PNECs were derived for all hazardous UV filters. Although, PNECs were often derived for various environmental compartments (i.e. freshwater, marine water, sediment, soil), results from literature focused on aquatic data. Effects as observed within scientific literature matches in principle with the hazardous profile of the UV filters. Effects levels both on the acute and the chronic toxicity as retrieved from the non‐standardized test organisms (literature) were above the derived PNECs under REACH. Currently, ERAs performed for cosmetic UV filters under REACH are solely tonnage driven and thus do not fully capture the use in sunscreens and associated leisure activities. Conclusion: Existing EU REACH regulation is considered as sufficient to evaluate the environmental safety of UV filters used in sunscreens. To cover the direct release of UV filters due to various leisure activities into the aquatic freshwater and marine environment, an additional application‐based ERA is considered necessary. For UV filters used in sunscreens, derived PNECs under REACH were evaluated against results from per reviewed scientific literature. This evaluation revealed that the PNECs derived from standard testing methods are protective for the environment. Existing environmental risk assessments as carried out under REACH in principal are fit for purpose, however may require some improvements related to the direct release of UV filter into the environment. [ABSTRACT FROM AUTHOR]

Phenolic benzotriazoles (BTZs) are used globally as light stabilizers in various plastic products to protect them from photooxidative degradation. The same physical–chemical properties that confer their functionality, like a sufficient photostability and a high octanol–water partition coefficient, also raise concerns on their potential for environmental persistence and bioaccumulation based on in silico predictive tools. To evaluate their bioaccumulation potential in aquatic organisms, standardized fish bioaccumulation studies according to OECD TG 305 were conducted with four of the most commonly used BTZs: UV 234, UV 329, UV P, and UV 326. The resulting growth‐ and lipid‐corrected BCF values revealed that UV 234, UV 329, and UV P were below the bioaccumulation threshold (BCF ≤ 2000), but UV 326 is considered very bioaccumulative (BCF ≥ 5000) with respect to the bioaccumulation criteria under REACH. Comparing these experimentally derived data with quantitative structure activity related or other calculated values using a logarithmic partitioning coefficient octanol–water (log Pow) driven mathematical formula revealed significant discrepancies demonstrating the weakness of current in silico approaches for this group of substances. Furthermore, available environmental monitoring data demonstrate that these rudimentary in silico approaches can lead to unreliable bioaccumulation estimates for this chemical class due to considerable uncertainties in underlying assumptions (e.g., concentration and route of exposure). However, using more sophisticated in silico methods (i.e., CATALOGIC base‐line model), the derived BCF values were better aligned with the experimentally derived ones. This paper studies the routing algorithms in the low earth orbit satellite network. Considering that the evaluation of inter‐satellite links in previous studies is relatively simple and the security of data transmission paths is poor, a linear programming routing algorithm based on a mathematical model and a multi‐object optimization Dijkstra algorithm are proposed. The simulation results show that they perform well in many respects. [ABSTRACT FROM AUTHOR]

In order to protect European Union (EU) drinking water resources from chemical contamination, criteria for identifying persistent, mobile, and toxic (PMT) chemicals and very persistent and very mobile (vPvM) chemicals under the EU REACH Regulation were proposed by the German Environment Agency (Umweltbundesamt—UBA). Additionally, new hazard classes for PMT and vPvM substances in the revised EU classification, labeling, and packaging (CLP Regulation) are intended. Therefore, a reliable approach in the identification of potential drinking water resource contaminants is needed. The scientific basis of the property‐based PMT/vPvM criteria, focusing on mobility, which dictates the migration of chemical drinking water sources, was evaluated, and a critical analysis of the deviation of sorption metrics from simple behavior was carried out. Based on our evaluation, a Koc may be used for nonionic substances on a screening level only, requiring a higher tier assessment. It is considered inappropriate for hydrophilic and ionizable chemicals, particularly for soils with low organic carbon contents. The nonextractable residue formation is complex and not well understood but remains significant in limiting the mobility of chemicals through soils and sediments. In order to inform the EU commission's work on the introduction of new hazard classes for PMT and vPvM substances into the European legislation, the derivation of a tiered approach is proposed, which utilizes the weight of evidence available, with adoption of appropriate higher tier models commensurate with the nature of the substance and the data available. Integr Environ Assess Manag 2023;19:775–791. © 2022 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC). Key Points: A Koc may be used for nonionic substances on a screening level only, requiring a higher tier assessment.The log Koc is considered inappropriate for hydrophilic and ionizable chemicals, particularly for soils with low organic carbon contents.Therefore, for the introduction of new hazard classes for PMT/vPvM substances into CLP, the derivation of a tiered approach is proposed, which utilizes the weight of evidence available, with adoption of appropriate higher tier models commensurate the nature of the substance and the data available. [ABSTRACT FROM AUTHOR]

Organic solvents are often used in aquatic toxicity tests to facilitate the testing of hydrophobic or poorly water-soluble substances such as ultraviolet (UV) filters, pesticides, or polycyclic aromatic hydrocarbons (PAHs). Knowledge of intrinsic effects (i.e., measured as standardized and non-standardized endpoints) of such carrier solvents in non-standardized organisms (i.e., corals), is critical to regulatory processes. Therefore, we exposed the reef-building coral Montipora digitata to the most commonly used carrier solvents ethanol, methanol, dimethyl sulfoxide, and dimethylformamide in the range of 10–100 µL L−1 for 16 days. The effects on mortality, photobiological, morphological, and oxidative stress markers were evaluated. In our study, all solvents resulted in significant morphological and/or oxidative stress responses, but not in mortality. Moreover, ethanol led to a rapid increase in turbidity, thus questioning its suitability as a carrier solvent in aquatic studies in general. Based on our observations, we could rank the solvent effects as follows: dimethylformamide < dimethyl sulfoxide ≈ methanol ≤ ethanol, with dimethylformamide showing the least and ethanol the most pronounced effects. We conclude that the use of solvents in toxicity studies with corals, particularly by examining non-standardized (e.g., morphological, physiological) endpoints, should be taken with caution and requires further elaboration. [ABSTRACT FROM AUTHOR]

Coral reefs have been declining globally at a historically unprecedented rate. Ultraviolet (UV) filters used in sunscreens may contribute to this decline at local scales, which has already led to bans on various organic UV filters in some regions. However, the underlying studies for these bans demonstrated significant flaws in the experimental design due to a lack of validated and standardized testing methods for corals. This study aimed to investigate options for the development of a standard acute toxicity test for the larval stage of scleractinian corals. Planula larvae of two brooding (Leptastrea purpurea and Tubastraea faulkneri) and two spawning (Acropora digitifera and A. millepora) species were exposed to the organic UV filter benzophenone-3 (BP3) for 48 h under static conditions. We observed interspecific variations in toxicity, with A. digitifera being the most sensitive (LC50 = 0.75 µg L−1) and T. faulkneri the least sensitive (LC50 = 2951.24 µg L−1) species. Inhibition of settlement was found to be a useful endpoint leading to an EC50 of 1.84 µg L−1 in L. purpurea larvae. Although the analytical challenges of measuring lipophilic substances in small volume test setups remain, the here applied test design and selected endpoints are suitable for further validation and subsequent standardization. [ABSTRACT FROM AUTHOR]

Ultraviolet (UV) filters used in sunscreens are among the anthropogenic substances that may enter the marine environment by both indirect (via wastewater) and direct pathways (leisure activities). Owing to the recent global decline in coral population, the impact of those UV filters on the coral health is currently under increased investigation. First results from scientists suggest that some of the filters may be toxic to various coral life stages, but an initial cross comparison with existing data from other freshwater organisms does not indicate that corals are specifically more susceptible to UV filters than other standard species. In fact, the available data leading to this conclusion is still vague and based on toxicity and bioaccumulation tests with corals, which are both still at the research stage. To facilitate a proper hazard assessment, robust experimental procedures for coral ecotoxicological studies are considered mandatory. In other words, additional steps should be taken to standardize and validate such new test systems to generate reliable results, which then can be used in regulatory decision making. Furthermore, to facilitate a more detailed and site‐specific environmental risk assessment in the marine area, an application‐based exposure scenario must be developed. Until these data and tools become available, environmental hazard and risk assessments may be carried out using existing data from freshwater organisms and existing tonnage‐based exposure scenarios as a potential surrogate. Integr Environ Assess Manag 2021;17:926–939. © 2021 SETAC KEY POINTS: UV filters are key ingredients in sunscreens, with a similar function but decidedly different in their physicochemical properties and environmental hazard profiles.Environmental risk assessments of UV filters are currently based on toxicity data from standard test organisms (i.e., algae, Daphnia, fish) and tonnage‐based exposure scenarios, making it difficult to assess their impacts on corals.Results indicate that this approach could also safeguard corals, although uncertainty exists linked to data quality and scenarios used.Standardized coral toxicity tests and application‐based exposure scenarios would certainly help to clarify existing uncertainties. [ABSTRACT FROM AUTHOR]

The amphibian metamorphosis assay represents an OECD Level 3 and EDSP Tier 1 ecotoxicity test assessing thyroid activity of chemicals in African clawed frog (Xenopus laevis). To evaluate the effectiveness of snout‐vent length (SVL) normalization of hindlimb length (HLL), correlation between the HLL and SVL or body weight was evaluated in the control groups of 10 individual studies from three laboratories. Two studies required separate analysis of the Nieuwkoop‐Faber (NF) stage ≤60 and >60 animals creating a total of 12 data sets. On study day 7, significant positive correlation between HLL and SVL or body weight was observed in eight and seven of the 10 data sets, respectively (r = 0.608‐0.843 and 0.583‐0.876). On study day 21, significant positive correlation between HLL and SVL or body weight was found in three and four of the 12 data sets, respectively (r = 0.452, 0.480 and 0.553 and r = 0.621, 0.546, 0.564 and 0.378). Significant positive correlation between HLL and SVL was found in three of five studies, including ≤NF stage 60 data (r = 0.564, 0.546 and 0.621). In one of eight studies, including >NF stage 60 data, the positive correlation between HLL and body weight was determined (r = 0.378). Negative or no correlation between HLL and SVL or body weight was found in the other late stage data sets. Therefore, use of SVL‐normalized HLL to assess thyroid‐mediated effects in X. laevis tadpoles is not warranted. HL stage relative to body stage should be considered. To evaluate normalized hindlimb length (HLL), the correlation between HL and either snout‐vent length or body weight was evaluated in the controls from 10 independently performed amphibian metamorphosis assay studies at study days 7 and 21. Based on the analysis, the HLL should not be used to assess thyroid axis activity, but a comparison of the developmental stage of the HL with the developmental stage of the rest of the larval body could be used more effectively to assess asynchronous development indicative of hypothalamic‐pituitary‐thyroid axis activity. [ABSTRACT FROM AUTHOR]

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. Unlabelled Image • Saturated solutions of octocrylene could not be reliably produced by passive dosing. • Experimental data for OCR: BCF = 858 L kg−1 (zebrafish), BMF: 0.0335 (rainbow trout) • Experimental BCF is in good agreement with BCF-estimation using OECD tools. [ABSTRACT FROM AUTHOR]

The bioaccumulation assessment of chemicals is challenging because of various metrics and criteria, multiple lines of evidence and underlying uncertainty in the data. Measured in vivo laboratory and field bioaccumulation data are generally considered preferable; however, quantitative structure-activity relationships (QSARs), mass balance models and in vitro data can also be considered. This case study critically evaluates in vivo, in vitro and in silico data and provides new data for the bioaccumulation assessment of triclosan (TCS). The review focusses on measured fish bioconcentration factors (BCFs) because this is the most commonly used regulatory metric. Reported measured fish BCFs range from about 20 to 8700 L/kg-ww spanning a range of possible bioaccumulation assessment outcomes, i.e. from “not bioaccumulative” to “very bioaccumulative”. Estimated biotransformation rate constants for fish obtained from in vivo, in vitro and in silico methods show general consensus fostering confidence in the selection of plausible values to confront uncertainty in the measured fish BCF tests. Other measurements (lines of evidence) from various species are also collected and reviewed. The estimated biotransformation rate constants and selected chemical property data are used to parameterize bioaccumulation models for aquatic species. Collectively the available lines of evidence are presented using a weight of evidence approach for assessing the bioaccumulation of TCS in aquatic species. Acceptable quality measured data and model predictions for TCS BCFs and bioaccumulation factors are lower than 2000 L/kg. Biomagnification factors are < 1 (kg/kg). The general consistency in the acceptable quality data is largely explained by the relatively efficient rates of TCS biotransformation in a range of species including measurements of significant in vitro activity of phase II conjugation reactions. The review demonstrates the value of combining models and measurements and, when necessary, applying multiple lines of evidence for chemical assessment. [ABSTRACT FROM AUTHOR]

A larval amphibian growth and development assay was performed to evaluate the potential effects of environmentally-relevant concentrations of triclosan (TCS) on amphibian development and growth. Xenopus laevis were exposed to TCS 0.0 (control), 6.3, 12.5 and 25.0 μg l-1 (estimated maximum tolerable concentration) until 10 weeks post-metamorphosis. At median metamorphosis time (Nieuwkoop and Faber stage 62), five larvae per replicate were collected for snout-vent length, hind limb length and body weight measurements, and histopathological examination of thyroid glands. Endpoints evaluated at test termination were based on draft guidance (USEPA, ) and included: survival; snout-vent length; body weight; gender; nuptial pad development (males); and liver, kidney, gonad and gonadal ducts histopathology. Exposure to TCS did not decrease survival, induce general signs of toxicity, affect median metamorphosis time or alter sex ratios. Exposure to TCS 12.5 and 25 μg l-1 increased growth during the metamorphic stages relative to the control, but did not influence growth during the post-metamorphic phase. Overall, several statistically significant findings were found in larvae exposed to TCS, such as a decrease in the prevalence of stage 3 Müllerian ducts in the anterior trunk sections of TCS 25.0 μg l-1 dose group females as compared to controls; most were not considered toxicologically relevant. Copyright © 2017 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

In the natural development of terrapins it occurs regularly that the eggs undergo embryonal development in a vertical position. Here from rises the question whether these vertically aligned eggs develop in the same way and show comparable hatching rates as horizontally aligned eggs do. For this matter, six clutches of the Red-bellied short-necked turtle (Emydura subglobosa) (Kreft, 1876) were incubated partly horizontally and vertically in order to investigate the efects on development, hatching success and anomaly rate of the hatchlings. The results show that the orientation of the eggs does not afect the development of the embryos, the hatching success or the number of scute anomalies. [ABSTRACT FROM AUTHOR]

Bei der natürlichen Eiablage von Wasserschildkröten kommt es immer wieder vor, dass Eier eine Embryonalentwicklung in senkrechter Lage vollziehen. Hieraus resultierte die Fragestellung, ob sich derartig senkrecht orientierte Eier in gleicher Weise entwickeln und vergleichbare Schlupfraten aufweisen, wie waagrecht orientierte. Daher wurden insgesamt sechs Gelege der Rotbauch-Spitzkopfschildkröte Emydura subglobosa (KREFFT, 1876) anteilig waagerecht bzw. senkrecht bebrütet, um Auswirkungen auf Entwicklung, Schlupf und Anomalienrate bei den Schlüpflingen zu untersuchen. Die Ergebnisse zeigten, dass die Lage der Eier keine Auswirkungen auf die Entwicklung des Embryos, die Schlupfrate oder die Anzahl auftretender Schildanomalien hatte. [ABSTRACT FROM AUTHOR]

The article offers information on the turtle fauna in Hogle Zoo, Salt Lake City, Utah in November 2015. Topics discussed include two female spotted turtles Clemmys guttata that were enclosed in a long aquaterrarium, an agile female yellow-botched map turtle Graptemys flavimaculata which has a mainly carnivorous diet, and the generally inactive Gopher tortoise Gopherus agassizzi. Also noted is the pancake tortoise Malacochersus tornieri that hide between rocks when danger arises.

A few days of visiting the island of Silhouette, the third largest granite island of the Seychelles, facilitated a trip to the bay of Grand Barbe on 29 Nov. 2015. A demanding 4.5-hour hike from the eastern to the western side of the island took us to the now-abandoned settlement of Grand Barbe where a total of five adult Arnold's Giant Tortoises, A. g. arnoldi (B already in 2007. Right upon arriving at the bay, one male specimen was spotted foraging for food. Owing to the stay being as brief as just one hour, no further specimens could be found. It may be safe to presume, however, that the other specimens were still present in this area, because previous observations indicate their home ranges to be relatively small. These A. g. arnoldi represent the only giant tortoises left on Silhouette Island, as all others have been evacuated from the island in early 2011. It was therefore all the more exciting to encounter these animals in the wild. [ABSTRACT FROM AUTHOR]

Im Rahmen eines mehrtätigen Aufenthaltes auf der Insel Silhouette, der drittgrößten Granitinsel der Seychellen, konnte am 29.11.2015 die Bucht von Grand Barbe besichtigt werden. Nach einer anspruchsvollen Wanderung von der Ostseite der Insel auf die Westseite wurde nach rund 4.5 h die mittlerweile verlassene Siedlung Grand Barbe erreicht, wo bereits 2007 insgesamt 5 adulte Arnold´s Riesenschildkröten A. g. arnoldi (Bour, 1982) gesehen wurden. Bereits unmittelbar nach der Ankunt an der Bucht wurde ein männliches Exemplar aufgefunden, welches gerade auf Nahrungssuche war. Aufgrund der kurzen Aufenthaltsdauer von lediglich einer Stunde, konnten an dem Tag keine weiteren Tiere aufgefunden werden. Jedoch war davon auszugehen, dass sich auch die anderen Tiere in diesem Gebiet auh ielten, da die bisher beobachteten Aktionsradi vergleichsweise klein waren. Bei den A. g. arnoldi handelt es sich um die einzigen auf der Insel Silhouette verbliebenen Riesenschildkröten, während alle anderen Tiere Anfang 2011 die Insel verlassen mussten. Umso erfreulicher war nun das Aui nden der Tiere in freier Wildbahn. [ABSTRACT FROM AUTHOR]

From 1997 until 2013 the habitat of the Seychelles wolf snake, Lycognathophis seychellensis (SCHLEGEL, 1837), at the Vallee de Mai, Praslin, Seychelles was observed during several field excursions. At total of 10 day excursions were carried out during November and December. Only two individuals of the Seychelles wolf snake could be found within the park area during a trip on November 25th, 2008. One of the individuals was bright in colouration whereas the other one was rather blackish. Both snakes were found by accident and were very shy. [ABSTRACT FROM AUTHOR]

Since the mid of the 20th century a relatively large population of the Dice snake Natrix tessellata (LAURENTI, 1768) it present at the lake Alpnachersee. During an excursion to the lake Alpnachersee, which is a side chain of the Lake Lucerne leaded by the Schildkröten-Interessengemeinschaft Schweiz (SIGS) individuals of this species could be observed in the habitat at short distance. The excursion took place at the Lopper mountain in the late morning of June 6th, 2010. Within a few meters of the lakeshore several Dice snakes could be observed either basking or mating. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Effects of Triclocarban, Triclosan, and Methyl Triclosan on Thyroid Hormone Action and Stress in Frog and Mammalian Culture Systems," by A. Hinther, C. M. Bromba, J. E. Wulff, and C. C. Helbing, published in volume 45 of the journal.

Coral reefs are globally declining due to various anthropogenic stressors. Amongst those, chemical pollutants, such as pesticides from agricultural runoff, sewage or an overabundance of personal care products in coastal waters due to intense tourism, may be considered as a local stressor for reef-building corals. The extent to which such chemicals exhibit toxic effects towards corals at environmentally relevant concentrations is currently controversially discussed and existing studies are often based on varying and sometimes deficient test methods. To address this uncertainty, we adapted available methods into a reliable and comprehensive acute coral toxicity test method for the reef-building coral Montipora digitata . The toxicities of the four substances benzophenone-3 (BP-3), Diuron (DCMU), copper (Cu 2+ as CuCl 2 , positive control) and dimethylformamide (DMF, solvent) were assessed in a 96 h semi-static test design. Endpoints such as maximum quantum yield, bleaching, tissue loss and mortality were evaluated with respect to their suitability for regulatory purposes. Overall, the endpoints bleaching and mortality yielded sensitive and robust results for the four tested substances. As the test method follows the principles of internationally standardized testing methods (ISO, OECD), it can be considered suitable for further validation and standardization. Once validated, a standardized test method will help to obtain reproducible toxicity results useful for marine hazard and risk assessment and regulatory decision making.