Outdoor Emissions
William J. Rea, Kalpana D. Patel in Reversibility of Chronic Disease and Hypersensitivity, Volume 4, 2017
Dispersants are called dispersants because that is what they do. They disperse oil; they do not destroy it. Dispersants sink the oil below the surface, making it harder to see. On August 20, scientists produced new evidence of vast undersea plumes of oil driving for miles. Another team confirmed the discovery of a massive 22 mile subsea oil plume the size of Manhattan and, most dismayingly, very little evidence that the oil was being broken down by microbes.475
Formulation strategies to modulate drug release from poloxamer based in situ gelling systems
Published in Expert Opinion on Drug Delivery, 2020
Hani Abdeltawab, Darren Svirskis, Manisha Sharma
Poloxamers are water-soluble tri-block copolymers with amphiphilic and surface-active properties. Poloxamers (Figure 1) are nonionic polymers, consisting of a central hydrophobic block of poly (propylene oxide) (PPO) and two hydrophilic terminal blocks of poly (ethylene oxide) (PEO). They have been employed as dispersants for pigments/inks, detergents, foaming agents and as anti-biofouling coatings [1]. Due to their biocompatibility poloxamers have been extensively used as excipients in pharmaceuticals such as, dispersing agent, emulsifiers, co-emulsifying agents, solubilizing agent, tablet lubricant, and wetting agent [2,3]. Over the last two decades, poloxamers based delivery platforms have grabbed the attention of formulation scientists and have been widely employed as drug carriers in ophthalmic [4], vaginal [5] and rectal drug delivery [6] due to the ease of administration and the ability to provide controlled release of drug following gelation [7,8].
Marine biofilm bacterial community response and carbon steel loss following Deepwater Horizon spill contaminant exposure
Published in Biofouling, 2019
Rachel L. Mugge, Jason S. Lee, Treva T. Brown, Leila J. Hamdan
Dispersant and dispersed oil induce different but sustained impacts on the composition of biofilms and metal loss. Dispersant is toxic to some populations of bacteria (Hamdan and Fulmer 2011), and dispersed oil droplets increase the solubility of oil in water, which may increase the toxicity of dispersed oil to marine microorganisms (Seidel et al. 2016). The distinct biofilm community that emerged in dispersed oil treatments in this study provides evidence that dispersed oil may favor taxonomic groups capable of withstanding its toxicity and metabolizing it. Concomitantly, metal loss and pitting in the dispersed oil treatments exceed other treatments that received the same contaminants separately. Dispersed oil may increase the potential for MIC, suggesting that exposure of marine biofilms on carbon steel surfaces to dispersed oil may have greater impacts on microbial communities and metal corrosion than previously thought.
Introducing a new standardized nanomaterial environmental toxicity screening testing procedure, ISO/TS 20787: aquatic toxicity assessment of manufactured nanomaterials in saltwater Lakes using Artemia sp. nauplii
Published in Toxicology Mechanisms and Methods, 2019
Seyed Ali Johari, Kirsten Rasmussen, Mary Gulumian, Mahmoud Ghazi-Khansari, Norihisa Tetarazako, Shosaku Kashiwada, Saba Asghari, June-Woo Park, Il Je Yu
Currently, regulatory use is essentially limited to the United States Environmental Protection Agency’s (USEPA) use of Artemia sp. for testing oil-spill dispersants. However, the Italian National Institute for Environmental Protection and Research, the Italian Water Research Institute, and the Italian Agency for Standardization in the Chemical sector proposed a protocol for testing immobilization/mortality of Artemia (APAT IRSA-CNR 2003). Several researchers have used Artemia sp. as a test organism for salt water aquatic nanotoxicology (Table 1). However, due to lack of an agreed and standardized protocol for testing aquatic toxicity using Artemia sp., data from these studies are effectively not reproducible. Moreover, important gaps in the description of the testing performed were identified (Libralato 2014), and Libralato proposed that, when reporting test results in future, parameters such as water oxygen saturation, pH, and conductibility should be stated. As that information could not be extracted from the literature reviewed it is not recorded in Table 1, but otherwise Table 1 reports on the degree to which Libralto's proposed parameters are reported in the reviewed literature.