 Many atmospheric chemicals occur in the gas phase as well as in liquid cloud droplets and aerosol particles Therefore, it is necessary to understand the distribution between the phases According to Henry's law, the equilibrium ratio between the abundances in the gas phase and in the aqueous phase is constant for a dilute solution Henry's law constants of trace gases of potential importance in environmental chemistry have been collected and converted into a uniform format The compilation contains 17 350 values of Henry's law constants for 4632 species, collected from 689 references It is also available at http://wwwhenrys-laworg 

/pdf/compilation-of-henry-s-law-constants-version-4-0-for-water-58il9q0ogv.pdf

Compilation of Henry's law constants (version 4.0) for water as solvent

http://www.kiwiscience.com/JournalArticles/EnvironPoll2011.pdf

A review of biochars’ potential role in the remediation, revegetation and restoration of contaminated soils

Bioremediation of high molecular weight polycyclic aromatic hydrocarbons: a review of the microbial degradation of benzo[a]pyrene.

The chemical interactions of hydrophobic organic contaminants (HOCs) with soils and sediments (geosorbents) may result in strong binding and slow subsequent release rates that significantly affect remediation rates and endpoints The underlying physical and chemical phenomena potentially responsible for this apparent sequestration of HOCs by geosorbents are not well understood This challenges our concepts for assessing exposure and toxicity and for setting environmental quality criteria Currently there are no direct observational data revealing the molecular-scale locations in which nonpolar organic compounds accumulate when associated with natural soils or sediments Hence macroscopic observations are used to make inferences about sorption mechanisms and the chemical factors affecting the sequestration of HOCs by geosorbents Recent observations suggest that HOC interactions with geosorbents comprise different inorganic and organic surfaces and matrices, and distinctions may be drawn along these lines,

Sequestration of hydrophobic organic contaminants by geosorbents

https://digital.csic.es/bitstream/10261/22454/3/SUPERCRITICAL%20FLUID%20EXTRACTION.pdf

Supercritical fluid extraction: Recent advances and applications

PAH loss during bioremediation of manufactured gas plant site soils

Bioconcentration and biokinetics of heavy metals in the earthworm

The propensity for groundwater ecosystems to recover from contamination by organic chemicals (in this case, coal-tar waste) is of vital concern for scientists and engineers who manage polluted sites. The microbially mediated cleanup processes are also of interest to ecologists because they are an important mechanism for the resilience of ecosystems. In this study we establish the long-term dynamic nature of a coal-tar waste-contaminated site and its microbial community. We present 16 years of chemical monitoring data, tracking responses of a groundwater ecosystem to organic contamination (naphthalene, xylenes, toluene, 2-methyl naphthalene and acenaphthylene) associated with coal-tar waste. In addition, we analyzed small-subunit (SSU) ribosomal RNA (rRNA) genes from two contaminated wells at multiple time points over a 2-year period. Principle component analysis of community rRNA fingerprints (terminal-restriction fragment length polymorphism (T-RFLP)) showed that the composition of native microbial communities varied temporally, yet remained distinctive from well to well. After screening and analysis of 1178 cloned SSU rRNA genes from Bacteria, Archaea and Eukarya, we discovered that the site supports a robust variety of eukaryotes (for example, alveolates (especially anaerobic and predatory ciliates), stramenopiles, fungi, even the small metazoan flatworm, Suomina) that are absent from an uncontaminated control well. This study links the dynamic microbial composition of a contaminated site with the long-term attenuation of its subsurface contaminants.

/pdf/subsurface-ecosystem-resilience-long-term-attenuation-of-4dcchkd6fy.pdf

Subsurface ecosystem resilience: long-term attenuation of subsurface contaminants supports a dynamic microbial community

The determination of a short-term LC 50 toxicity value for a chemical is a useful indicator of the potential biological effect of the chemical if released into the environment. However, it is possible that adverse effects of the chemical may occur at sublethal concentrations far below LC 50 values. Using the earthworm Eisenia fetida (Savigny) as an indicator organism for soil ecosystems, concentrations of 10 organic chemicals were evaluated for sublethal effects on earthworm growth and reproduction. Following short-term exposure to sublethal concentrations of carbaryl and dicldrin, E. fetida was allowed to resume growth and reproduction to determine whether such effects were permanent. The effect on earthworm populations as a representative soil organism could be a sentinel for the effects of more destructive soil processes.

Growth and reproduction of the earthworm Eisenia fetida exposed to sublethal concentrations of organic chemicals.

The toxicity and uptake of polycyclic aromatic hydrocarbons (PAHs) by earthworms were measured in soil samples collected from manufactured-gas plant sites having a wide range in PAH concentrations (170-42,000 mg/kg) and soil characteristics. Samples varied from vegetated soils to pure lampblack soot and had total organic carbon contents ranging from 3 to 87%. The biota-soil accumulation factors (BSAFs) observed for individual PAHs in field-collected earthworms (Aporrectodea caliginosa) were up to 50-fold lower than the BSAFs predicted using equilibrium-partitioning theory. Acute toxicity to the earthworm Eisenia fetida was unrelated to total PAH concentration: Mortality was not observed in some soils having high concentrations of total PAHs (>42,000 mg/kg), whereas 100% mortality was observed in other soils having much lower concentrations of total PAHs (1,520 mg/kg). Instead, toxicity appeared to be related to the rapidly released fraction of PAHs determined by mild supercritical CO2 extraction (SFE). The results demonstrate that soils having approximately 16,000 mg rapidly released total PAH/kg organic carbon can be acutely toxic to earthworms and that the concentration of PAHs in soil that is rapidly released by SFE can estimate toxicity to soil invertebrates.

Supercritical carbon dioxide extraction as a predictor of polycyclic aromatic hydrocarbon bioaccumulation and toxicity by earthworms in manufactured-gas plant site soils

Edward F. Neuhauser

Papers

PAH loss during bioremediation of manufactured gas plant site soils

Bioconcentration and biokinetics of heavy metals in the earthworm

Subsurface ecosystem resilience: long-term attenuation of subsurface contaminants supports a dynamic microbial community

Growth and reproduction of the earthworm Eisenia fetida exposed to sublethal concentrations of organic chemicals.

Supercritical carbon dioxide extraction as a predictor of polycyclic aromatic hydrocarbon bioaccumulation and toxicity by earthworms in manufactured-gas plant site soils