Inhibition of soil microbial activity by nitrogen‐based energetic materials

• Published in: Environmental toxicology and chemistry 2017-11, Vol.36 (11), p.2981-2990
• Main Authors: Kuperman, Roman G., Minyard, Morgan L., Checkai, Ronald T., Sunahara, Geoffrey I., Rocheleau, Sylvie, Dodard, Sabine G., Paquet, Louise, Hawari, Jalal
• Format: Article
• Language: English
• Subjects: Acetone; Bacteria - drug effects; Bioavailability; Biological activity; Biomass; Carbon dioxide; Cell Respiration - drug effects; Contaminants; Dinitrotoluene; Ecological risk assessment; Energetic materials; Environmental protection; Explosives; Loam; Microbial activity; Microorganisms; Nitrogen; Nitrogen Compounds - toxicity; Nitroglycerin; Organic chemicals; Organic chemistry; Public domain; Respiration; Sandy loam; Sandy soils; Sassafras - drug effects; Slurries; Soil - chemistry; Soil contamination; Soil investigations; Soil Microbiology; Soil Pollutants - toxicity; Soil pollution; Soil toxicity; Soil water; Soils; Toxicity; Toxicity Tests
• ISSN: 0730-7268; 1552-8618
• DOI: 10.1002/etc.3862

We investigated individual toxicities of the nitrogen‐based energetic materials (EMs) 2,4‐dinitrotoluene (2,4‐DNT); 2‐amino‐4,6‐dinitrotoluene (2‐ADNT); 4‐amino‐2,6‐dinitrotoluene (4‐ADNT); and nitroglycerin (NG) on microbial activity in Sassafras sandy loam (SSL) soil, which has physicochemical characteristics that support very high qualitative relative bioavailability for organic chemicals. Batches of SSL soil for basal respiration (BR) and substrate‐induced respiration (SIR) assays were separately amended with individual EMs or acetone carrier control. Total microbial biomass carbon (biomass C) was determined from CO2 production increases after addition of 2500 mg/kg of glucose–water slurry to the soil. Exposure concentrations of each EM in soil were determined using US Environmental Protection Agency method 8330A. Basal respiration was the most sensitive endpoint for assessing the effects of nitroaromatic EMs on microbial activity in SSL, whereas SIR and biomass C were more sensitive endpoints for assessing the effects of NG in soil. The orders of toxicity (from greatest to least) were 4‐ADNT > 2,4‐DNT = 2‐ADNT > NG for BR; but for SIR and biomass C, the order of toxicity was NG > 2,4‐DNT > 2‐ADNT = 4‐ADNT. No inhibition of SIR was found up to and including the greatest concentration of each ADNT tested in SSL. These ecotoxicological data will be helpful in identifying concentrations of contaminant EMs in soil that present acceptable ecological risks for biologically mediated processes in soil. Environ Toxicol Chem 2017;36:2981–2990. Published 2017 Wiley Periodicals Inc. on behalf of SETAC.This article is a US government work and, as such, is in the public domain in the United States of America.