Effects, uptake, and fate of 2,4,6‐trinitrotoluene aged in soil in plants and worms

Abstract

Abstract-The present study was aimed at providing data to be used at predicting exposure-based effects of 2,4,6-trinitrotoluene (TNT) aged in soil on endpoint organisms representing two trophic levels. These data can be used to define criteria or reference values for environmental management and conducting specific risk assessment. Long-term exposure tests were conducted to evaluate sublethal toxicity and uptake of aged soil-based explosives, with TNT as the main contaminant. In these tests, plants were exposed for 55 d, and biomass and explosives residues were determined. Worms were exposed for 28 and 42 d, and biomass, number, and tissue residues were determined. Biomass of Lolium perenne significantly decreased with soil-TNT concentration, and an effective concentration causing a 20% decrease in biomass (EC20) for TNT metabolites of 3.75 mg/kg was calculated. The concentrations of TNT metabolites in shoots and roots were significantly related to concentrations in soil, as were concentrations of hexahydro-1,3,5-trinitro-1,3,5 triazine (RDX) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX). The mean bioconcentration factors, indicating the potential of a chemical to accumulate in an organism, were 0.9 for TNT metabolites, 71.8 for RDX, and 12.2 for HMX in L. perenne shoots. Biomass of Eisenia fetida adults significantly decreased with soil-TNT concentration, and an EC20 for TNT of 3.70 mg/kg was calculated. The TNT, RDX, and HMX levels in E. fetida were below detection.

Soils contaminated with explosives: Environmental fate and evaluation of state-of-the-art remediation processes (IUPAC Technical Report)

“…For Medicago sativa, Echinochloa crusgall L., and Lolium perenne L., EC 20 values for TNT range from 43 to 62 mg/kg while DNT was found to be more phytotoxic (EC 20 values ranging from 3 to 24 mg/kg) than TNT [212]. Similarly, Best et al [227] determined that the EC 20 value for TNT metabolites was 3.75 mg/kg for Lolium perenne. Robidoux et al [214] determined that Hordeum vugare was not affected by HMX fractions (up to 1866 ± 438 mg/kg) while Best et al [215] determined that Lolium perenne was not impacted by RDX up to 1540 mg/kg.…”

“…Of the studies conducted, root elongation, seedling emergence, biomass production, and photosynthesis parameters have been used as phytotoxicity indicators. The majority of studies have been undertaken using agricultural species (Table 6) with more recent studies investigating phytotoxic effects on rye grass [212,226,227] and Arabidopsis [228]. While impacts on the aforementioned indicator parameters have been reported, few studies have determined NOEC, LOEC, EC 20 , or EC 50 values for explosive compounds (Table 5).…”

Toxicity and Uptake of 2,4,6-Trinitrotoluene (TNT) in Contaminated Soils to Eisenia fetida

“…매우 높은 농도 편차를 보인다 (Best et al, 2008). 또한 TNT는 토양내 장기간 잔존하며, 지표수 및 지하수를 따 라 확산이 쉽게 이루어지므로 인근 토양, 지하수, 하천 등 에 서식하는 생태계 뿐만 아니라 인체에도 직, 간접적인 영향을 미칠 수 있다 (Gong et al, 1999;Lachance et al, 2004).…”

“…독성평가 자료는 오염 기준치 설정, 환경관리 기준치 참 조값, 위해성 평가수행에 대한 해당오염물질의 영향을 예 측하는데 이용될 수 있다 (Best et al, 2008). 지렁이는 환경오염물질에 대하여 빠르고 민감하게 반응하므로 토양 오염을 평가할 수 있는 훌륭한 지표생물로 사용되어져 왔 다 (Best et al, 2008;Kuperman et al, 2009;Lachance et al, 2004;Renoux et al, 2000).…”

“…지렁이는 환경오염물질에 대하여 빠르고 민감하게 반응하므로 토양 오염을 평가할 수 있는 훌륭한 지표생물로 사용되어져 왔 다 (Best et al, 2008;Kuperman et al, 2009;Lachance et al, 2004;Renoux et al, 2000). 지렁이는 토양내 TNT 오염에 대하여 민감성을 가지는 것으로 알려져 있는 데, Renoux et al(2000)은 TNT의 LC 50 이 약 143 mg/ kg 이상, LOEC가 약 140 mg/kg으로 보고하였으며, *Corresponding author : wshin@mail.knu.ac.kr Received : 2015.…”