Immunotoxicity of explosives-contaminated soil before and after bioremediation

Soils from the Yorktown Naval Base contaminated with trinitrotoluene (TNT) and other explosives were used to prepare eluates before and after bioremed iation using microbial growth amendments in the presence (P1 eluates) or ab sence (P2 eluates) of exogenous white rot fungus. Effectiveness of bioremed iation was examined by several immunotoxicity assays-viability/growth of ly mphocytes, cytokine production, and expression of the interleukin-2 (IL-2) receptor-using human peripheral blood mononuclear cells exposed to the elua tes. Although TNT concentrations decreased in both P1 and P2 eluates relati ve to untreated baseline soil (BL) eluates, a recovery in lymphocyte growth /viability and IL-2 secretion was seen with P2 but not P1 eluates relative to BL eluates. IL-2 receptor levels were higher in cells exposed to BL and P2 eluates than when exposed to P1 eluates. Interferon-gamma, tumor necrosi s factor-beta, and IL-10 levels were highest in BL and P2 eluates and lowes t in P1 eluates. Taken together, these results suggest that treatment of th e soil with microbial growth amendments in the absence but not the presence of exogenous white rot fungi lead to partial bioremediation as assessed by lymphocyte functions.