A method, utilizing brine shrimp (Artemia salina Leach), is proposed as a simple bioassay for natural product research. The procedure determines LC (50) values in microg/ml of active compounds and extracts in the brine medium. Activities of a broad range of known active compounds are manifested as toxicity to the shrimp. Screening results with seed extracts of 41 species of Euphorbiaceae were compared with 9KB and 9PS cytotoxicities. The method is rapid, reliable, inexpensive, and convenient as an in-house general bioassay tool.

Degradation of 11 pyrethroids was measured over approximately 100 days in three sediment/water systems under aerobic and anaerobic conditions at 25 °C in the dark. The three California sediments represented a range of textures and organic matter. Test compounds were bifenthrin, cypermethrin, ζ-cypermethrin, cyfluthrin, β-cyfluthrin, deltamethrin, esfenvalerate, fenpropathrin, γ-cyhalothrin, λ-cyhalothrin, and permethrin. A non-standard design was employed to keep conditions essentially the same for all compounds. The test compounds were applied as two test mixtures (six active ingredients per mixture, with bifenthrin common to both) at approximately 50 μg of test compound/kg of sediment (dry weight). Extracts of sediment/water were cleaned up by solid-phase extraction, concentrated, and analyzed by gas chromatography/mass spectrometry (except deltamethrin) against matrix-matched standards, with cyfluthrin-d6 as an internal standard. Deltamethrin was analyzed by liquid chromatography/tandem mass spectrometry using deltamethrin-phenoxy-(13)C6 as an internal standard. Similar degradation rates of bifenthrin and for related isomeric compounds (e.g., cyfluthrin and β-cyfluthrin) were generally measured in both mixtures for each sediment. First-order half-lives under aerobic conditions ranged from 2.9 to greater than 200 days, with a median value of 18 days. Under anaerobic conditions, the range was from 20 to greater than 200 days, with a median value of 70 days.

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There have been many attempts to compile comprehensive lists of flame retardants. However, this goal has proven challenging due to the heterogeneity of compounds that can be used as flame retardants coupled with changes in formulation chemistry over time. Flame retardants have been the focus of many recent existing hazard, exposure, and risk assessments. These assessments have been class-based or for individual chemical substances. Here, diverse sets of publicly available data sources from governmental organizations and the open literature were compiled to develop an inventory of chemicals used as flame retardants and organohalogen flame retardants. The chemical substances from these data sources were mapped to appropriate chemical identifiers via manual curation and deduplicated. Despite different data sources containing a large number of overlapping chemical substances, compiling information from multiple data sources was found to increase the breadth of potential flame retardant chemistries. The flame retardant and organohalogen flame retardant inventories were developed as a resource for scientists interested in better understanding properties of flame retardant and organohalogen flame retardant classes.