Logo image
The fate of inhaled 14C-labeled PCB11 and its metabolites in vivo
Journal article   Open access   Peer reviewed

The fate of inhaled 14C-labeled PCB11 and its metabolites in vivo

Xin Hu, Andrea Adamcakova-Dodd and Peter S Thorne
Environment international, Vol.63, pp.92-100
02/2014
DOI: 10.1016/j.envint.2013.10.017
PMID: 24275706
url
https://doaj.org/article/0872b81aa82b4553a788e958ded74c16View
Open Access

Abstract

Background: The production ban of polychlorinated biphenyl (PCB) technical mixtures has left the erroneous impression that PCBs exist only as legacy pollutants. Some lower-chlorinated PCBs are still being produced and contaminate both indoor and ambient air. Objectives: To inform PCB risk assessment, we characterized lung uptake, distribution, metabolism and excretion of PCB11 as a signature compound for these airborne non-legacy PCBs. Methods: After delivering [(14)C]PCB11 to the lungs of male rats, radioactivity in 34 major tissues and 5 digestive matter compartments was measured at 12, 25, 50, 100, 200 and 720min postexposure, during which time the excreta and exhaled air were also collected. [(14)C]PCB11 and metabolites in lung, liver, blood, digestive matter, urine, feces, and adipose tissues were extracted separately to establish the metabolic profile of the disposition. Results: [(14)C]PCB11 was distributed rapidly to all tissues after 99.8% pulmonary uptake and quickly underwent extensive metabolism. The major tissue deposition of [(14)C]PCB11 and metabolites translocated from liver, blood and muscle to skin and adipose tissue 200min postexposure, while over 50% of administered dose was discharged via urine and feces within 12h. Elimination of the [(14)C]PCB11 and metabolites consisted of an initial fast phase (t½=9-33min) and a slower clearance phase to low concentrations. Phase II metabolites dominated in liver blood and excreta after 25min postexposure. Conclusions: This study shows that PCB11 is completely absorbed after inhalation exposure and is rapidly eliminated from most tissues. Phase II metabolites dominated with a slower elimination rate than the PCB11 or phase I metabolites and thus can best serve as urine biomarkers of exposure. Keywords: BW; Biodistribution; Biomarkers; CYP; GI; Inhalation; MeSO(2); Metabolism; OH-PCB; PCB; Persistent organic pollutants; Polychlorinated biphenyl; biological half-life; body weight; cytochrome P450; gastrointestinal; hydroxylated polychlorinated biphenyl; methylsulfonyl; polychlorinated biphenyl; t(½).
ISRP Project 7 Inhalation Toxicology Core ISRP Project 7 2015-2020 Synthesis Core

Details

Metrics

Logo image