title: Evaluation of tissue and cellular biomarkers to assess 2,4,6-trinitrotoluene (TNT) exposure in earthworms: effects-based assessment in laboratory studies using Eisenia andrei.
abstract: The lysosomal neutral red retention time (NRRT) assay, a biomarker for lysosomal membrane stability, and the total immune activity (TIA) assay, a measure of non-specific immune system activity, were used in laboratory studies to assess the toxic effects of 2,4,6-trinitrotoluene (TNT) on earthworms (Eisenia andrei) in vivo. The results were compared with the concentration of TNT and its metabolites in earthworm tissue, as well as standard sublethal toxicity endpoints including growth (i.e. weight change) and reproduction effects from previously published studies. Filter paper experiments indicated a significant decrease in NRRT at >or=1.8 micro g TNT cm(-2), whereas sublethal (weight loss) and lethal effects to earthworms were detected at >or=3.5 and 7.1 micro g TNT cm(-2), respectively. Experiments in artificial soil showed that NRRT effects could be detected at lower TNT concentrations (>or=55 mg TNT kg(-1) soil dry weight) compared with other sublethal endpoints (effects on growth and reproduction). The TIA biomarker did not significantly respond to TNT. Copper (as CuSO4, filter paper contact tests) and 2-chloroacetamide (soil tests), which were used as reference toxicants, also decreased the NRRT. The use of the NRRT assay linked with tissue concentrations of TNT metabolites in earthworms was identified as a potentially appropriate biomarker approach for TNT exposure assessment under laboratory conditions and a novel tool for effects-based risk assessment.
authors.affiliation: Applied Ecotoxicology Group, Biotechnology Research Institute, National Research Council of Canada, 6100 Royalmount Avenue, Montreal, Quebec, H4P 2R2, Canada. Pierre-Yves.Robidoux@nrc.ca
authors.forename: Pierre Yves
authors.initials: PY
authors.lastname: Robidoux
authors.forename: Claus
authors.initials: C
authors.lastname: Svendsen
authors.forename: Manon
authors.initials: M
authors.lastname: Sarrazin
authors.forename: Jalal
authors.initials: J
authors.lastname: Hawari
authors.forename: Sonia
authors.initials: S
authors.lastname: Thiboutot
authors.forename: Guy
authors.initials: G
authors.lastname: Ampleman
authors.forename: Jason M
authors.initials: JM
authors.lastname: Weeks
authors.forename: Geoffrey I
authors.initials: GI
authors.lastname: Sunahara
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000032:analysis; D004784:Environmental Monitoring; D007107:Immune System / Q000187:drug effects; D008247:Lysosomes / Q000378:metabolism; D009499:Neutral Red; D009835:Oligochaeta / Q000187:drug effects* / Q000276:immunology / Q000378:metabolism*; D018570:Risk Assessment; D012989:Soil Pollutants / Q000493:pharmacokinetics / Q000633:toxicity; D014303:Trinitrotoluene / Q000493:pharmacokinetics* / Q000633:toxicity*
chemical_list: D015415:Biomarkers; D012989:Soil Pollutants; D014303:Trinitrotoluene; D009499:Neutral Red