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Plastic pollution is a source of chemical to the environment and wildlife. Despite the ubiquity of plastic pollution and thus plastic additive in the environment, plastic additives have been studied to a limited extend. As a prerequisite to a study aiming to evaluate the leaching of a common additive used as an antioxidant (Irgafos® 168) from polyethylene microparticles, an inventory of the potential background contamination of the laboratory workplace was done. In this study, Irgafos® 168 (tris(2,4-ditert-butylphenyl) phosphite) and its oxidized form (tris (2,4ditert-butylphenyl) phosphate) were quantified in different laboratory reagents, including the plastic packaging and the powders, using Pyrolysis-GC/MS. At least one form of Irgafos® 168 was detected in all tested laboratory reagents with higher concentrations in caps and bottles as compared to the powders. Additionally, oxidized Irgafos® 168 was also found in the reverse osmosed and deionized water container used in the laboratory. The same profile of contamination, i.e. higher concentration of the oxidized form and higher concentrations in acidic reagents, was observed when comparing the reagent and their respective containers suggesting that the additive is leaching from the container into the powder. Overall, this study demonstrates that the antioxidant additive Irgafos® 168 is ubiquitous in the laboratory workplace. Plastic additives such as Irgafos® 168 can therefore largely interfere and biased ecotoxicological and toxicological studies especially using environmentally relevant concentrations of microplastics. The source, fate and effects of plastic additive from plastic debris should be carefully considered in future studies that require setting up methods to overcome these contaminations.

Coral reefs around the world are under threat due to anthropogenic impacts on the environment. It is therefore important to develop methods to monitor the status of the reefs and detect changes in the health condition of the corals at an early stage before severe damage occur. In this work, we evaluate underwater hyperspectral imaging as a method to detect changes in health status of both orange and white color morphs of the coral species Lophelia pertusa . Differing health status was achieved by exposing 60 coral samples to the toxic compound 2-methylnaphthalene in concentrations of 0 mg L −1 to 3.5 mg L −1 . A machine learning model was utilized to classify corals according to lethal concentration (LC) levels LC5 (5% mortality) and LC25 (25% mortality), solely based on their reflectance spectra. All coral samples were classified to correct concentration group. This is a first step towards developing a remote sensing technique able to assess environmental impact on deep-water coral habitats over larger areas.

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