Bench-scale testing of a novel soil PFAS treatment train for informed remedial planning and decision-making

Bench-scale batch tests were conducted to assess the potential applicability of a combined separation/concentration/destruction treatment train to address soils and sediments impacted by per- and polyfluoroalkyl substances (PFAS) contamination at Schriever Space Force Base with historic aqueous film-forming foam (AFFF). Specifically, a novel treatment train coupling soil washing (for treatment of impacted soil/sediment) with foam fractionation (for treatment of the wash water [WW] generated during soil washing) and electrochemical oxidation (ECO, for treatment of the foam fractionate generated during foam fractionation) was evaluated at the bench scale using site-specific materials. Results presented herein show that the AFFF-impacted sandy soils with low organic content were amenable to treatment via soil washing. However, the removal of hydrophobic PFAS, such as perfluorooctanesulfonic acid (PFOS), from the organic-rich sediments was challenging. Results from batch desorption experiments were within a factor of 2 of those generated by soil washing bench studies, suggesting that simple batch tests can potentially be used to reasonably predict the treatment efficacy of soil washing. Long-chained perfluoroalkyl acids (PFAAs) within the WW were removed more effectively in the foam fractionation studies as compared to short-chain PFAAs. Addition of a surfactant, such as cetrimonium bromide (CTAB), enhanced foaming but only marginally improved the treatment of short-chained PFAAs and in some cases inhibited PFOS removal. ECO reduced PFAS concentrations in the foam fractionate generated during foam fractionation by several orders of magnitude. However, generation of unwanted byproducts may warrant further treatment and/or disposal. Overall, results from this study provide a novel data set highlighting the site-dependent nature of these PFAS remedial technologies and how simple, low-cost bench tests can be reliably leveraged for informed decision-making during PFAS remedial planning.     

Cleanup levels for pcbs and their combustion products at an industrial facility

In 1991, a fire occurred at a foundry in western Pennsylvania. The fire started in capacitors that contained polychlorinated biphenyls (PCBs) and subsequent sampling has indicated that PCBs and products of their incomplete combustion, the polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs), were released as a result of the fire. This article develops and provides justification for site-specific cleanup levels for the PCBs, PCDDs, and PCDFs accidentally released into this industrial facility during the fire. Cleanup levels were calculated using standard risk assessment approaches and assumptions, and these riskbased values were compared with cleanup criteria used for other sites. Final criteria were established based on this comparison and a consideration of such site-specific factors as migration potential, industrial use patterns, and the small mass of material present.     

Sex pheromones and attractants in the Eucosmini and Grapholitini (Lepidoptera,Tortricidae)

Summary The geometric isomers (E,E)-, (E,Z)-, (Z,E)-, and (Z,Z)-8,10-dodecadien-1-yl acetate were identified as sex pheromone components or sex attractants in the tribes Eucosmini and Grapholitini of the tortricid subfamily Olethreutinae. Species belonging to the more ancestral Tortricinae were not attracted. Each one isomer was behaviourally active in males ofCydia andGrapholita (Grapholitini), either as main pheromone compound, attraction synergist or attraction inhibitor. Their reciprocal attractive/antagonistic activity in a number of species enables specific communication with these four compounds.Pammene, as well as otherGrapholita andCydia responded to the monoenic 8- or 10-dodecen-1-yl acetates. Of the tribes Olethreutini and Eucosmini,Hedya, Epiblema, Eucosma, andNotocelia trimaculana were also attracted to 8,10-dodecadien-1-yl acetates, but several otherNotocelia to 10,12-tetradecadien-1-yl acetates. The female sex pheromones ofC. fagiglandana, C. pyrivora, C. splendana, Epiblema foenella andNotocelia roborana were identified. (E,E)- and (E,Z)-8,10-dodecadien-1-yl acetate are producedvia a commonE9 desaturation pathway inC. splendana. CallingC. nigricana andC. fagiglandana females are attracted to wingfanning males.     

Fluctuating asymmetry and nutritional condition of Baltic cod (<Emphasis Type="Italic">Gadus morhua</Emphasis>) larvae

The level of fluctuating asymmetry (FA), defined as random deviations from perfect bilateral symmetry, is assumed to reflect the developmental instability (DI) of an organism. Because environmental and genetic stress may increase DI, FA has been used to assess the level of stress experienced by, for example, fish. In this study, left–right asymmetry of lapillar otoliths was related to nutritional condition as estimated from RNA/DNA ratios, in order to investigate the utility of FA to detect feeding-related stress in Baltic cod, Gadus morhua L., larvae. Cod larvae in intermediate and good nutritional condition showed similar values of FA, and these were more symmetric than for larvae in poor condition. As increased levels of FA were restricted to larvae in a condition comparable to that of larvae experiencing at least 3 days of starvation in laboratory experiments, it is suggested that FA is an insensitive indicator of short-term feeding success of larval cod. However, FA can be used to reveal severely starved larva populations and probably also populations that have been subjected to prolonged sub-optimal feeding conditions.     

The red and the black: habituation and the dear-enemy phenomenon in two desert Pheidole ants

Many species of territorial animals are more aggressive toward strangers than neighbors, a pattern of aggression referred to as the ’dear-enemy phenomenon.’ In many cases, the mechanism by which neighbors are discriminated from strangers and the function of neighbor-stranger discrimination remain controversial. We investigated the spatial patterns of inter-colony aggression within and between two Pheidole species of seed-harvesting ants in the Mojave Desert of California by quantifying aggression between colonies in standardized staged encounters. We also tested whether the level of fighting between workers of two colonies is affected by previous exposure to each other. We show that neighbors (i.e., colonies less that 2.6 m away) of either species are treated less aggressively than more distant colonies and that habituation may be a mechanism by which this discrimination is achieved. The variation in aggression among spatially distant colonies also suggests that additional genetic or environmental factors are involved in recognition. The function of the dear-enemy phenomenon in these ant species may be related to the greater risk to the resources of a colony presented by strange workers than workers from a neighboring colony. Received: 18 November 1999 / Received in revised form: 3 April 2000 / Accepted: 3 May 2000     

Host acceptance behaviour of the small ermine moth Yponomeuta cagnagellus: larvae and adults use different stimuli

Summary. The sugar alcohol dulcitol is a strong feeding stimulant for larvae of the small ermine moth Yponomeuta cagnagellus. In this paper we tested the hypothesis that dulcitol also acts as an oviposition stimulant for this species. We found that the sugar-alcohol dulcitol was present on the surface of the host Euonymus europaeus. We also showed that (as yet unidentified compounds) can be systemically transferred (i.e. by uptake and transport via the vascular system) from E. europaeus, to the non-host Crataegus monogyna and stimulate oviposition. However, no evidence was found that this stimulatory activity was due to dulcitol. Systemic enrichment of C. monogyna with dulcitol did not induce oviposition on this plant. Neither was the application of pure dulcitol on artificial twigs effective. In addition it was shown that when dulcitol was removed from host plant extracts, oviposition stimulatory activity was retained in the fraction without dulcitol. Synergism between dulcitol and other stimulants could not be demonstrated, however, high concentrations of dulcitol in combination with the main stimulant(s) showed a trend towards enhanced oviposition. It is concluded that the sugar alcohol dulcitol can only play a limited role in adult host acceptance behaviour. The hypothesis that a host shift in the genus Yponomeuta from Celastraceae to Rosaceae might have been facilitated by the presence of small amounts of dulcitol in Rosaceae therefore needs to be restricted to larval feeding behaviour. Received 20 August 1999; accepted 6 December 1999     

Comparison of percolation to batch and sequential leaching tests: Theory and data

Leaching tests are becoming more relevant in assessing solid waste material, particularly with respect to groundwater risks. In the field, water infiltration is the dominant leaching mechanism, which is simulated in the lab with batch and column tests. In this study, we compared percolation, through analytical solutions of the advection–dispersion equation, to laboratory batch and sequential leaching tests. The analytical solutions are supported with comprehensive data from various field and laboratory leaching of different solutes from waste materials and soils collected in long-term joint research projects funded by the German Federal Ministry for Education and Research and the Federal Environment Agency. The comparison of theory and data is facilitated if concentrations and cumulative release are plotted versus the liquid–solid ratios (LS). Both theory and data indicate that leaching behaviour is independent of duration and physical dimensions of the leaching tests. This holds even if field lysimeters are compared to laboratory columns of different size, different flow velocities as well as different contact times. In general, laboratory batch tests over predict effluent concentrations (for LS < K_d). Leaching of solutes from solid samples of certain materials (e.g. chloride from incineration ashes or sulphate from demolition waste) in column and lysimeter tests compares very well and agrees with the analytical solutions. Overall, reproducibility and agreement with theory of column tests are better than batch tests, presumably because the latter are prone to artefacts (e.g. in liquid–solid separation steps). Theory and data fit surprisingly well, despite the fact that the theory is based on the local equilibrium assumption; non-linear sorption and chemical reactions in the solid waste materials are not considered.     

The environmental and biosecurity characteristics of livestock carcass disposal methods: A review

Livestock mortalities represent a major waste stream within agriculture. Many different methods are used throughout the world to dispose of these mortalities; however within the European Union (EU) disposal options are limited by stringent legislation. The legal disposal options currently available to EU farmers (primarily rendering and incineration) are frequently negatively perceived on both practical and economic grounds. In this review, we assess the potential environment impacts and biosecurity risks associated with each of the main options used for disposal of livestock mortalities in the world and critically evaluate the justification for current EU regulations. Overall, we conclude that while current legislation intends to minimise the potential for on-farm pollution and the spread of infectious diseases (e.g. transmissible spongiform encephalopathies, bacterial pathogens), alternative technologies (e.g. bioreduction, anaerobic digestion) may provide a more cost-effective, practical and biosecure mechanism for carcass disposal as well as having a lower environmental footprint. Further social, environmental and economic research is therefore warranted to assess the holistic benefits of alternative approaches for carcass disposal in Europe, with an aim to provide policy-makers with robust knowledge to make informed decisions on future legislation.     

Preparation and Properties of Thermoplastic Starch/Montmorillonite Nanocomposite Using N-(2-Hydroxyethyl)formamide as a New Additive

N-(2-Hydroxyethyl)formamide (HF) was synthesized efficiently and used as a new additive to prepare thermoplastic starch/montmorillonite nanocomposite (TPS/MMT). Here, HF acted as both plasticizer for TPS and swelling agent for MMT. The hydrogen bond interaction among HF, starch and MMT was proven by Fourier-transform infrared (FT-IR) spectroscopy. By scanning electron microscope (SEM), starch granules were completely disrupted. Atomic force microscopy demonstrated that partially exfoliated TPS/MMT nanocomposite was formed. The crystallinity of corn starch, MMT, HF-plasticized TPS (HTPS) and TPS/MMT nanocomposite was characterized by X-ray diffraction (XRD). Thermal stability of HTPS and TPS/MMT was determined by thermogravimetric analysis (TGA). The water resistance of TPS/MMT nanocomposite increased compared with that of pure HTPS. Tensile strengths of TPS/MMT nanocomposites were higher than those of HTPS, but just the reverse for elongations at break.     

Levels and trends of polybrominated diphenylethers and other brominated flame retardants in wildlife

In this paper, we review the available data for polybrominated diphenylethers (PBDEs) and other flame retardants in wildlife, with the exception of fishes from Europe and North America which are covered in more detail elsewhere. More data are available for PBDEs than for other compounds, and these show that some of these compounds have become widely distributed in the environment, being found in samples from Europe, Australia, Azerbaijan, North America and the Arctic. Most available data relate to birds and their eggs and marine mammals, but the results of two food web studies are also included. The detection of PBDEs in pelagic marine mammals which feed in deep offshore waters, including baleen whales, indicate that these compounds have found their way into deep-water, oceanic food webs as well as the coastal/shallow sea examples described in detail. In the North Sea study, the most marked increase in lipid-normalised concentrations of six BDE congeners occurred during transfer from predatory fish to marine mammals. In the St. Lawrence Estuary study, marked differences in the ratios observed between species suggested that some fish species may be able to metabolise BDE99.A number of time trend studies have also been conducted, notably in guillemot eggs from Sweden (1969-2000), beluga whales from the Canadian Arctic (1982-1997 and 1989-2001) and from the St. Lawrence Estuary (1988-1999), and ringed seals from the Canadian Arctic (1981-2000). In the temperate latitudes, from these and other studies (e.g. in dated sediment cores), PBDE concentrations began to rise earlier than in those from high latitudes, in line with data for production and use. These trends have now slowed in many cases. Declines could be expected in Europe for many congeners following the cessation of manufacture and use of the penta-mix formulation in the EU, though these are not yet apparent in environmental samples. In Arctic biota, however, the rapidly rising concentrations seen currently in Canada could be expected to continue for some time, reflecting continued production and use of the penta-mix formulation in North America (>95% of the world total) and the impact of long-range atmospheric transport.