Main Content

The World of Protozoa, Rotifera, Nematoda and Oligochaeta

Ref ID : 6130

Sabine G. Dodard, Justin Powlowski, and Geoffrey I. Sunahara; Biotransformation of 2,4,6-trinitrotoluene (TNT) by enchytraeids (Enchytraeus albidus) in vivo and in vitro. Environmental Pollution 131:263-273, 2004

Reprint

In File

Notes

2,4,6-Trinitrotoluene (TNT) is toxic to soil invertebrates, but little is known about its toxicokinetic behavior in soil. Tissue residure analysis was used to evaluate whether the presence of TNT and its reduced metabolites in soil invertebrates was due to uptake of these compounds from the soil into the organism, or due to microbial transformation of TNT associated with the organism followed by uptake. Adult white potworms (Enchytraeus albidus) were exposed to non-lethal concentrations of TNT in amended artificial soil for 21 days, or to TNT in solution for 20 hr. Soil exposure studies confirmed earlier reports that TNT was transformed in enchytraeids in vivo to 2- and 4-aminodinitrotoluenes. However, enchytraeid exposure to TNT in solution led to the additional presence of 2,4-diaminonitrotoluene as well as 2- and 4- hydroxyamino-dinitrotoluenes and azoxy-compounds, suggesting that TNT can be metabolized in vivo in the absence of soil. Incubation of unexposed enchytraeid homogenates with TNT led to a protein-dependent appearance of these metabolites in vitro after >/_16 hr rincubation. Cellular fractionation studies indicated that most of this activity resided in the 8000x g pellet, and was completely inhibited by broad-spectrum antibiotics. These studies demonstrate that enchytraeids can transform TNT in vivo and in vitro, at least in part, by bacteria associated with the host organism.