Metabolic Fate of 2,4-Dichlorophenol and Related Plant Residues in Rats

Abstract

This study compared the metabolic fate of [(14)C]-DCP, [(14)C]-residues from radish plants, and purified [(14)C]-DCP-(acetyl)glucose following oral administration in rats. A rapid excretion of radioactivity in urine occurred for [(14)C]-DCP, [(14)C]-DCP-(acetyl)glucose, and soluble residues, 69, 85, and 69% within 48 h, respectively. Radio-HPLC profiles of 0-24 h urine from rats fed [(14)C]-DCP and [(14)C]-DCP-(acetyl)glucose were close and qualitatively similar to those obtained from plant residues. No trace of native plant residues was detected under the study conditions. The structures of the two major peaks were identified by MS as the glucuronide and the sulfate conjugates of DCP. The characterization of a dehydrated glucuronide conjugate by MS and NMR of DCP was unusual. In contrast to soluble residues, bound residues were mainly excreted in feces, 90% within 48 h, whereas total residues were eliminated in both urine and feces. For total residues, the radioactivity in feces was higher than expected from the percentage of soluble and bound residues in radish plants. This result highlighted that less absorption took place when residues were present in the plant matrix as compared to plant-free residues and DCP.

Nontarget Screening of Novel Urinary Biomarkers for Occupational Exposure to Toxic Chemicals from Coking Industry Using HPLC-QTOF-MS

“…Additionally, phenols and their sulfate conjugates were detected in the urine of workers from coking sites, which are a group of compounds that cannot be overlooked in coking sites . Phenols are typically excreted as glucuronide and sulfate conjugates through urine. , This led to significantly higher levels of PCP, propylphenol isomer, and trimethylphenol sulfate isomer in the urine of workers at the coking sites. Of particular concern is PCP, which has been identified as a carcinogen .…”

“…43 Phenols are typically excreted as glucuronide and sulfate conjugates through urine. 44,45 This led to significantly higher levels of PCP, propylphenol isomer, and trimethylphenol sulfate isomer in the urine of workers at the coking sites. Of particular concern is PCP, which has been identified as a carcinogen.…”

Coking-Produced Aromatic Compounds in Urine of Exposed and Nonexposed Populations: Exposure Levels, Source Identification, and Model-Based Health Implications

“…Phenolic compounds, including CPs and NPs, were also detected in urine samples, representing 0.91% and 1.78% of the total concentration within the occupational exposure group (Figure S2). CPs and NPs can be metabolized by CBs and NBs, respectively. − Moreover, they have also been detected in coking sites in their original forms. , Upon entering the human body, they are subsequently excreted as conjugates in urine . Levels of CPs were significantly higher in the occupational exposure group (0.87 μg·g –1 Cr) compared to the nonoccupational exposure (0.74 μg·g –1 Cr) and control groups (0.61 μg·g –1 Cr) (Figure S1).…”

“…2,21 Upon entering the human body, they are subsequently excreted as conjugates in urine. 59 Levels of CPs were significantly higher in the occupational exposure group (0.87 μg•g −1 Cr) compared to the nonoccupational exposure (0.74 μg•g −1 Cr) and control groups (0.61 μg• g −1 Cr) (Figure S1). Among these, PCP concentrations were elevated in the occupational exposure group compared to nonoccupational exposure and control groups (p < 0.001).…”

Effective synthesis of sulfate metabolites of chlorinated phenols

“…However, there is considerable evidence that sulfates and glucuronides are important biotransformation products of chlorophenols and other chlorinated environmental pollutants in many species, including fish (Cravedi et al, 1999; Layiwola et al, 1983; Oikari and Anas, 1985; Stehly and Hayton, 1989), rats (Chadwick et al, 1981; Hawkins et al, 1980; Hissink et al, 1997; Hissink et al, 1996; Klos and Dekant, 1994; Pascal-Lorber et al, 2012) and humans (Pekari et al, 1991; Renner and Mucke, 1986; Ye et al, 2005). Particularly noteworthy is an investigation of saw-mill workers exposed to chlorophenols, which suggests that sulfation is a dominant urinary excretion pathway for low concentrations of chlorophenols (Pekari et al, 1991).…”