Disease relevance of HSDB 5293

• Characterization of a novel TOL-like plasmid from Pseudomonas putida involved in 1,2,4-trimethylbenzene degradation [1].
• Growth of E. coli was strongly affected by low concentrations of pseudocumene and its products [2].
• Fetal toxicity, expressed as significant reduction in fetal body weight, occurred at 600 and 1200 ppm mesitylene, and at 600 and 900 ppm pseudocumene [3].
• Significant decrease in maternal body weight gain and food consumption was observed at concentrations of 300 ppm mesitylene, 600 ppm pseudocumene, or greater [3].

High impact information on HSDB 5293

• The inhalation pharmacokinetics of dichloromethane and toluene as well as two de novo compounds (1,2,4-trimethyl benzene and ethyl benzene) were extrapolated from rat to human, using the present modeling methodology [4].
• A strain of Pseudomonas (P. putida HS1) was found to resemble P. putida (arvilla) mt-2 in its ability to degrade toluene, m- and p-xylene, 1,2,4-trimethylbenzene (pseudocumene), and 3-ethyltoluene via oxidation of a methyl substituent and reactions of the meta-fission pathway [5].
• On the basis of the favorable conditions provided by the two-liquid phase system, engineering of the initial pseudocumene concentration allowed exploiting the complex kinetics of the multistep reaction for the exclusive production of 3,4-dimethyl- benzaldehyde [6].
• A physiologically based toxicokinetic model was developed for inhalation exposure of 1,2,4-trimethylbenzene (TMB) in man [7].
• In summary, the no-observed-adverse-effect-level (NOAEL) for maternal toxicity was 100 ppm for mesitylene and 300 ppm for pseudocumene, and the NOAEL for developmental toxicity was 300 ppm for mesitylene and pseudocumene [3].

Chemical compound and disease context of HSDB 5293

• The developmental toxicity of two trimethylbenzene isomers, mesitylene (1,3,5-trimethylbenzene) and pseudocumene (1,2,4-trimethylbenzene) was studied in Sprague-Dawley rats following inhalation exposure [3].

Biological context of HSDB 5293

• Metabolic constants, Km (mg/l) and Vmax (mg/h/kg), the parameters for pseudocumene biotransformation by rats were estimated (3,4-DMBA - Km = 28, Vmax = 96; 2,4-DMBA - Km = 7, Vmax = 25; 2,5-DMBA - Km = 7, Vmax = 23) [8].
• METHODS: We assessed percutaneous absorption of ethylene glycol (EG), isopropyl alcohol (IA) and 1,2,4-trimethylbenzene (TMB), using static diffusion cells [9].

Anatomical context of HSDB 5293

• Following the inhalation exposure, pseudocumene concentrations were estimated in the brain, liver and lung homogenates, as well as in the brain (brainstem, hippocampus, temporal cortex, cerebellum) and blood (arterial, venous) structures [10].
• Inhalation exposure to pseudocumene for 90 days increased the total number of cell macrophages, polymorphonuclear leukocytes and lymphocytes number at all three test concentrations compared with the controls [11].

Associations of HSDB 5293 with other chemical compounds

• Neurotoxic effects of acute and subchronic inhalation exposure to trimethylbenzene isomers (pseudocumene, mesitylene, hemimellitene) in rats [12].
• In our earlier research on rats we have proved that inhalation exposure to pseudocumene or hemimellitene at concentrations close to the MAC value results in behavioral changes detectable many weeks after cessation of the exposure [13].
• Neurotoxic and sensory respiratory irritation effects of 1,2,4-trimethylbenzene (pseudocumene) in male rats and male Balb/C mice were investigated in condition of acute inhalation exposure [14].
• Subsequent peaks were identified by gas chromatography-mass spectrometry as styrene, myrcene, 1,2,4-trimethylbenzene, 1,8-cineole, and linalool in a proportion of 50: 21: 0.5: 27: 1.5, respectively [15].

Analytical, diagnostic and therapeutic context of HSDB 5293

• In the present work, the determination of 1,2,4-trimethylbenzene in the serum of a person exposed to the solvent vapor during the handling of liquid scintillation counting cocktails is described [16].
• Blood concentrations of pseudocumene were estimated by gas chromatography using the headspace technique [8].

References