Review of Decontamination Techniques for the Inactivation of Bacillus anthracis and Other Spore-Forming Bacteria Associated with Building or Outdoor Materials.

Since the intentional release of Bacillus anthracis spores through the U.S. Postal Service in the fall of 2001, research and development related to decontamination for this biological agent have increased substantially.

Impact of sporicidal fumigation with methyl bromide or methyl iodide on electronic equipment.

The effect of sporicidal fumigation with methyl bromide or methyl iodide on the functionality of valuable electronic equipment was evaluated using desktop computers as surrogates under target conditions of 200-250 mg/L fumigant for 48 h at 24-30 °C and 75-85% RH. Methyl iodide fumigation damaged light-emitting diodes and optical films in computer displays that were powered-on during fumigation. After five months of post-fumigation operation, five out of six methyl-bromide-fumigated and all six methyl-iodide-fumigated DVD ± RW optical drives failed.

Surfactant-induced bacterial community changes correlated with increased polycyclic aromatic hydrocarbon degradation in contaminated soil.

Bioremediation as a method for removing polycyclic aromatic hydrocarbons (PAHs) from contaminated environments has been criticized for poor removal of potentially carcinogenic but less bioavailable high molecular weight (HMW) compounds. As a partial remedy to this constraint, we studied surfactant addition at sub-micellar concentrations to contaminated soil to enhance the biodegradation of PAHs remaining after conventional aerobic bioremediation. We demonstrated increased removal of four- and five-ring PAHs using two nonionic surfactants, polyoxyethylene(4)lauryl ether (Brij 30) and polyoxyethylene sorbitol hexaoleate (POESH), and analyzed bacterial community shifts associated with those conditions.

Improving Polycyclic Aromatic Hydrocarbon Biodegradation in Contaminated Soil Through Low-Level Surfactant Addition After Conventional Bioremediation.

Efficacy of bioremediation for soil contaminated with polycyclic aromatic hydrocarbons (PAHs) may be limited by the fractions of soil-bound PAHs that are less accessible to PAH-degrading microorganisms. In previous test-tube-scale work, submicellar doses of nonionic surfactants were screened for their ability to enhance the desorption and biodegradation of residual PAHs in soil after conventional bioremediation in a laboratory-scale, slurry-phase bioreactor. Polyoxyethylene sorbitol hexaoleate (POESH) was the optimum surfactant for enhancing PAH removal, especially the high-molecular weight PAHs.

Screening Nonionic Surfactants for Enhanced Biodegradation of Polycyclic Aromatic Hydrocarbons Remaining in Soil After Conventional Biological Treatment.

A total of five nonionic surfactants (Brij 30, Span 20, Ecosurf EH-3, polyoxyethylene sorbitol hexaoleate, and R-95 rhamnolipid) were evaluated for their ability to enhance PAH desorption and biodegradation in contaminated soil after treatment in an aerobic bioreactor. Surfactant doses corresponded to aqueous-phase concentrations below the critical micelle concentration in the soil-slurry system. The effect of surfactant amendment on soil (geno)toxicity was also evaluated for Brij 30, Span 20, and POESH using the DT40 B-lymphocyte cell line and two of its DNA-repair-deficient mutants.

Identification of anthraquinone-degrading bacteria in soil contaminated with polycyclic aromatic hydrocarbons.

Quinones and other oxygenated polycyclic aromatic hydrocarbons (oxy-PAHs) are toxic and/or genotoxic compounds observed to be cocontaminants at PAH-contaminated sites, but their formation and fate in contaminated environmental systems have not been well studied. Anthracene-9,10-dione (anthraquinone) has been found in most PAH-contaminated soils and sediments that have been analyzed for oxy-PAHs. However, little is known about the biodegradation of oxy-PAHs, and no bacterial isolates have been described that are capable of growing on or degrading anthraquinone.

Bioavailability of (Geno)toxic Contaminants in Polycyclic Aromatic Hydrocarbon-Contaminated Soil Before and After Biological Treatment.

Contaminated soil from a former manufactured-gas plant site was treated in a laboratory-scale bioreactor. Desorbability and biodegradability of 14 polycyclic aromatic hydrocarbons (PAHs) and 4 oxygenated PAHs (oxy-PAHs) were investigated throughout a treatment cycle. Desorbability was determined using a mixed-function sorbent (Oasis HLB) or a hydrophobic sorbent (Tenax) in dialysis tubing suspended in the soil slurry.