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Wildlife Toxicity Assessments for Chemicals of Military Concern is a compendium of chemical-specific toxicity information with discussions on the rationale and development of Wildlife Toxicity Reference Values (TRVs) intended for use on terrestrial wildlife for risk assessment applications. Substances covered include military-related chemicals including explosives, propellants, pesticides and metals. Wildlife Toxicity Assessments for Chemicals of Military Concern is a much-needed resource designed to meet the needs of those seeking toxicological information for ecological risk assessment purposes. Each chapter targets a specific chemical and considers the current knowledge of the toxicological impacts of chemicals to terrestrial wildlife including mammalian, avian, amphibian and reptilian species. Provides detailed information on how Wildlife Toxicity Values (TRVs) for military chemicals of concern are derived and evaluated. Covers wildlife toxicity assessments of explosives, metals and environmental chemicals. Compiles relevant information on the environmental effects of chemicals on wildlife in relation to public and environmental health.

Nanoparticles (NPs) can potentially cause adverse effects on organ, tissue, cellular, subcellular, and protein levels due to their unusual physicochemical properties (e.g., small size, high surface area to volume ratio, chemical composition, crystallinity, electronic properties, surface structure reactivity and functional groups, inorganic or organic coatings, solubility, shape, and aggregation behavior). Metal NPs, in particular, have received increasing interest due to their widespread medical, consumer, industrial, and military applications. However, as particle size decreases, some metal‐based NPs are showing increased toxicity, even if the same material is relatively inert in its bulk form (e.g., Ag, Au, and Cu). NPs also interact with proteins and enzymes within mammalian cells and they can interfere with the antioxidant defense mechanism leading to reactive oxygen species generation, the initiation of an inflammatory response and perturbation and destruction of the mitochondria causing apoptosis or necrosis. As a result, there are many challenges to overcome before we can determine if the benefits outweigh the risks associated with NPs. WIREs Nanomed Nanobiotechnol 2010 2 544–568 This article is categorized under: Toxicology and Regulatory Issues in Nanomedicine > Toxicology of Nanomaterials

Abstract
Carbon nanotube (CNT) as a reinforcement enhances durability and performance of concrete composites. Exposure to some forms of CNT is known to cause adverse pathological outcomes. To understand potential toxicity arising from use of CNT-enabled concrete composites as it goes through various occupational life cycle stages, we evaluated 1) the physicochemical characteristics and toxicity of the as-produced CNT and 2) how particulate release during concrete manipulation (e.g., cutting) is altered by CNT incorporation. Physical dimensional profiling indicated a geometric mean length of 0.72 µm and 32 nm in diameter. The toxicity of the as-produced CNT was similar to an agglomerated CNT studied in our previous research, lacking the more severe toxicity associated with longer length and diameter CNT. Four concrete test samples, three different formulations with CNT and one without, were cut in a specialized chamber to simulate an occupational scenario. The mass median aerodynamic diameters from varying CNT incorporated composites did not change and was 5.23 µm in diameter. No free CNT was captured in the aerosols or was visible on the surface of the concrete. The toxicity of the released particulate is currently being investigate using in vitro screening tests designed to investigate mechanisms of potential toxicity. There were minimal changes in the particulate size distribution profiles after cutting, suggesting adding CNT to concrete may have subtle effects on the toxicity of the generated particulate.

Brominated flame retardants (BFRs) are chemicals used in e.g. electronic equipment, textiles and plastics for the prevention of fire. Over recent decades, concern has been raised regarding some heavily used BFRs, since the levels in the environment have been increasing. In the present thesis, persistent, bioaccumulative, and toxic (PBT) properties were studied for a structurally varied set of BFRs selected to represent more than 60 organic BFRs. The studied BFRs include: 2,4,4'-tribromodiphenyl ether (BDE 28), 2,2',3,4,4',5',6-heptabromodiphenyl ether (BDE 183), decabromodiphenyl ether (BDE 209), hexabromocyclododecane (HBCD), tetrabromobisphenol A (TBBPA), tetrabromobisphenol A 2-hydroxyethyl ether (TBBPA OHEE), 2,4,6-tribromophenol (246BrPh), 1,2-dibromo-4-(1,2-dibromoethyl)cyclohexane (TBECH), and hexabromobenzene (HxBrBz). It is likely that soil will act as a sink for BFRs. Therefore, studies of BFRs were performed on persistence in soil, and on bioaccumulation from soil in the earthworm Eisenia fetida. Large variation in the biodegradability in soil among the tested BFRs was observed. The studied brominated diphenyl ethers (BDE 28 and BDE 209) were very persistent under both aerobic and anaerobic conditions, while 246BrPh and TBECH degraded quickly in both aerobic and anaerobic soil. The bioaccumulation in earthworm from soil was high for HxBrBz, TBECH and for tested brominated diphenyl ethers with 4-6 bromine atoms (BDE 47, BDE 99, and BDE 153). Bioaccumulation was also studied in zebrafish after dietary exposure to a mixture of BFRs. It was shown that several metabolites were formed and retained in zebrafish, which highlights the importance of also searching for and identifying persistent degradation products. Maternal transfer was shown for all BFRs present in the female zebrafish. This shows that zebrafish young (fry) are exposed to these BFRs at approximately the same concentrations as female zebrafish during the early-life stages, when fish are usually most sensitive to organic contaminants. Toxicity of individual BFRs and a BFR mixture was studied in Nitocra spinipes using a silica gel-based system. Highest toxicities were observed for BDE 28, TBBPA, and TBBPA OHEE. In the mixture toxicity study, simultaneous exposure to low concentrations (individually causing no significant effect) of six BFRs significantly affected the survival of Nitocra spinipes. The results from the PBT studies presented in the thesis and literature data were compared with the criteria for PBT classification, as set in the European REACH legislation. Further, some BFRs with physico-chemical properties similar to those of identified PBTs were suggested to be prioritized for future PBT testing.