Ž . Mutation Research 444 1999 25–39 www.elsevier.comrlocatergentox Community address: www.elsevier.comrlocatermutres Cytotoxic and genotoxic effects of energetic compounds on bacterial and mammalian cells in vitro 1 Bernard Lachance a, ) , Pierre Yves Robidoux a , Jalal Hawari a , Guy Ampleman b , Sonia Thiboutot b , Geoffrey I. Sunahara a a Biotechnology Research Institute, National Research Council of Canada, 6100 Royalmount AÕenue, Montreal, Quebec, Canada H4P 2R2 ´ ´ b Defense Research Establishment Valcartier, Ministry of National Defense, 2459, Pie XI BlÕd., Val Belair, Quebec, Canada G3J 1X5 ´ ´ Received 14 October 1998; received in revised form 1 April 1999; accepted 28 April 1999 Abstract Ž . Ž . The mutagenicity and toxicity of energetic compounds such as 2,4,6-trinitrotoluene TNT , 1,3,5-trinitrobenzene TNB , Ž . Ž . hexahydro-1,3,5-trinitro-1,3,5-triazine RDX and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine HMX , and of aminornitro derivatives of toluene were investigated in vitro. Mutagenicity was evaluated with the Salmonella fluctuation Ž . test FT and the V79 Chinese hamster lung cell mutagenicity assay. Cytotoxicity was evaluated using V79 and TK6 human lymphoblastic cells. For the TK6 and V79 assays, TNB and 2,4,6-triaminotoluene were more toxic than TNT, whereas RDX Ž and HMX were without effect at their maximal aqueous solubility limits. The primary TNT metabolites 2-amino-4,6-di- . nitrotoluene, 4-amino-2,6-dinitrotoluene, 2,4-diamino-6-nitrotoluene and 2,6-diamino-4-nitrotoluene were generally less cytotoxic than the parent compound. The FT results indicated that TNB, TNT and all the tested primary TNT metabolites were mutagenic. Except for the cases of 4-amino-2,6-dinitrotoluene and 2,4-diamino-6-nitrotoluene in the TA98 strain, addition of rat liver S9 resulted in either no effect, or decreased activity. None of the tested compounds were mutagenic for the V79 mammalian cells with or without S9 metabolic activation. Thus, the FT assay was more sensitive to the genotoxic effects of energetic compounds than was the V79 test, suggesting that the FT might be a better screening tool for the presence of these explosives. The lack of mutagenicity of pure substances for V79 cells under the conditions used in this study does not preclude that genotoxicity could actually exist in other mammalian cells. In view of earlier reports and this study, mutagenicity testing of environmental samples should be considered as part of the hazard assessment of sites contaminated by TNT and related products. q 1999 Elsevier Science B.V. All rights reserved. Keywords: Explosive; Trinitrotoluene; Salmonella typhimurium; V79 mutagenicity assay; TK6 cytotoxicity assay 1. Introduction Contamination of soil and groundwater by 2,4,6- Ž . trinitrotoluene TNT and other energetic compounds ) Corresponding author. Tel.: q1-514-496-8087; fax: q1-514- 496-6265; E-mail: bernard.lachance@nrc.ca 1 Assigned NRCC Publication a41846. is an international problem having multiple facets. Field surveys have revealed that concentrations of these energetic contaminants can be sufficiently high to adversely impact environmental health, as de- wx scribed in a report by Ryon et al. 1 . Some of the major contaminants present on these sites, namely Ž . TNT, hexahydro-1,3,5-trinitro-1,3,5-triazine RDX Ž . and 2,4-dinitrotoluene 2,4-DNT are also considered by the U.S. EPA as possible human carcinogens, 1383-5718r99r$ - see front matter q 1999 Elsevier Science B.V. All rights reserved. Ž . PII: S1383-5718 99 00073-X