Cytotoxicity of Dinitrotoluenes (2,4-DNT, 2,6-DNT ) to MCF-7 and MRC-5 Cells

Abstract

DNTs are considered possibly carcinogenic to humans (Group 2B) because there is inadequate evidence in humans for carcinogenicity though there is sufficient evidence in experimental animals. In this study, MCF-7 (breast) and MRC-5 (lung) cells were exposed to a serial dilution of 2,4 and 2,6 DNTs (control, 1–500 ppm) in 96 well tissue culture plates. After various time intervals (24, 48, 72 and 96 hrs) the plates were washed, and 100 μl fluorescein diacetate solution (10 μg/ml in PBS) was added column wise to each well, and incubated at 37°C for 30–60 min before reading the fluorescence with a spectrofluorometer at excitation and emission wavelengths of 485 and 538 nm respectively. Spectrofluorometeric readings were converted to percentages of cell survival. Regression analysis was conducted to determine the relationship between cell survival and exposed concentration. Linear equations derived from the regression analysis were used to calculate the LC 50 values. Results indicated that 2,6 DNT as more toxic to breast cells; LC50 values were 445 and 292 ppm at 24 and 48 hours respectively compared to 2,4 DNT showing LC50 values of 570 and 407 ppm at 24 and 48 hours, respectively. No significant differences in toxicity existed between the two chemicals with regard to lung cells. Contrary to the above observation, 2,4 DNT was more toxic to breast cells; LC50 values were 407 and 238 ppm at 24 and 48 hours respectively compared to lung cells showing LC50 values of 527 and 402 ppm at 24 and 48 hours respectively. No significant difference existed for 2,6 DNT between the two cell lines. Lungs cells were more resistant to the two chemicals.

Dose-related Effects Following Oral Exposure of 2,4-Dinitrotoluene on the Western Fence Lizard, Sceloporus occidentalis

“…2,4-Dinitrotoluene (2, is an explosive chemical that has a wide variety of uses. Specifically, 2,4-DNT is used in the production of polyurethane foam for bedding and furniture industries and as a gelatinizing agent in explosives, ammunition, and dyes [1,2]. Additionally, 2,4-DNT is an intermediate in the production of 2,4,6-trinitrotoluene and is released in the effluent following 2,4,6-trinitrotoluene manufacturing.…”

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2,4-dintitrotoluene (2, is an explosive frequently found in the soil of military installations. Because reptiles can be common on these sites, ecological risk assessments for compounds such as 2,4-DNT could be improved with toxicity data specific to reptiles.

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New insights into dissociation of deprotonated 2,4‐dinitrotoluene by combined high‐resolution mass spectrometry and density functional theory calculations

“…The contamination of water sources exposes fishes to physiological and biochemical changes that have a negative effect on the growth process in carp . That the risk of carcinogenicity has been widely studied in humans underscores the importance of detecting these compounds . The United States Environmental Protection Agency (US EPA) classifies DNT as a priority pollutant, and the standard detection methods are gas chromatography (GC) and high‐performance liquid chromatography (HPLC) .…”

2,4-Dinitrotoluene (DNT) Perturbs Yolk Absorption, Liver Development and Lipid Metabolism/Oxygen Transport Gene Expression in Zebrafish Embryos and Larvae

“…2,4-Dinitrotoluene (2,4-DNT) belongs to the family of nitrobenzene compounds, and it is widely used in the production of polyurethane, dyes, pesticides and rubber, and is the main component in specific explosive mixtures [1,2]. Exposure to 2,4-DNT can induce cancer in laboratory animals and may result in cancer in humans, as 2,4-DNT was classified as a group 2B human carcinogenic compound (possibly carcinogenic to humans) by the International Agency for Research on Cancer of the World Health Organization [3], and was listed as a priority pollutant by the U.S. Environmental Protection Agency [4].…”