Determination of dioxin-like compounds utilizing in vitro bioassays such as ethoxyresorufin-O-deethylase (EROD) or chemical-activated luciferase expression (DR-CALUX) is an important tool to evaluate their Ah receptor-mediated toxic effects. The aim of this study is to describe advantages and limitations of these bioassays using rat hepatoma (H4IIE) wildtype and recombinant H4IIE cells in a 96 well microtiter plate format. We are using these bioassays for the evaluation of relative responses (REP) from several congeners of dioxins (e.g., 2,3,4,7,8-PCDF) or dioxin-like compounds (PCB-126, 2,3,4,7,8-PBDF) to 2,3,7,8-TCDD. In addition, total toxic equivalency factors (TEFs) of mixtures of these dioxin-like compounds from several kinds of matrices such as feed, sediment, or thermal waste residues are measured by both bioassays and additional chemical analysis. These samples were measured in a cross-validation study between two laboratories using the DR-CALUX technology in comparison to the H4IIE-EROD assay and chemical analysis. Improvement of the quality criteria of the newly developed DR-CALUX bioassays in comparison to the EROD bioassay was demonstrated (higher coefficient of determination r(2); better repeatability of TCDD and samples), while induction factor, limit of detection, and limit of quantification have been similar. The tested samples showed positive responses in both bioassays using different kinetics (EROD: 72 h; DR-CALUX: 24 h). Ratio of measured toxicity equivalent (TEQ) values varied around mean values of 0.89 (comparing both DR-CALUX laboratories, ranging from 0.68-3.1), 2.0 (comparing EROD and DR-CALUX, ranging from 0.57-8.1), and 1.6-2.5 (comparing EROD-TEQ and I-TEQ, mean 1.6, ranging from 1.0-3.9; for DR-CALUX/I-TEQ, 2.5; 0.61-8.3), respectively. This demonstrates that these bioassays can be used as alternative screening technology for monitoring I-TEQ values in various standards and matrices.
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http://dx.doi.org/10.1093/toxsci/69.1.125 | DOI Listing |
Chemosphere
December 2024
Department of Civil, Urban, Earth, and Environmental Engineering, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, Republic of Korea; UNIST Environmental Analysis Center, Ulsan National Institute of Science and Technology (UNIST), Ulsan, 44919, Republic of Korea. Electronic address:
Adv Nutr
December 2024
Division of AgriLife Research, Texas A&M Agriculture, Food and Nutrition Evidence Center, AgriLife Research, Fort Worth, TX, United States; Department of Nutrition, Texas A&M University, College Station, Texas, United States.
Determining dietary recommendations for seafood consumed during pregnancy, lactation, and childhood requires consideration of the known nutritional benefits and potential harm due to toxicant exposure as they relate to child outcomes. This study aimed to describe the scope of the evidence associated with seafood-related toxicant exposure and child outcomes and to identify toxicant-outcome pairs that may have sufficient evidence to conduct a systematic review. We included studies examining seafood toxicant exposure during pregnancy, lactation, and childhood, and child outcomes.
View Article and Find Full Text PDFHeliyon
October 2024
R &D Department, Shakheh Zeytoon Lian Co., Bushehr, Iran.
Discarded cigarette waste may leach toxic elements and can contaminate different environments. In this study, the levels of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in cigarette butts (CBs) leachates were determined, and the release rate of these pollutants from three CBs types such as smoked CBs with and without tobacco (SCBs and SFs) and unsmoked filters (USFs) were examined. The mean concentration levels of PCBs compounds were
Environ Int
December 2024
School of Public Health and Emergency Management, Southern University of Science and Technology, Shenzhen, Guangdong 518055, PR China. Electronic address:
Dioxin is a typical class of persistent organic pollutants (POPs) that could cause cancer. In China, the contribution of dietary dioxins to the cancer burden remains underexplored. This study evaluates the cancer risk and burden due to dietary dioxins and dioxin-like compounds among Chinese residents from 2000 to 2020.
View Article and Find Full Text PDFTalanta
February 2025
Water Management and Treatment Technologies Research Group, Climate Change and Sustainability Vice Presidency, TUBITAK Marmara Research Center, 41470, Gebze, Kocaeli, Turkey. Electronic address:
The polychlorinated dibenzo-p-dioxins/furans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (dl-PCBs) are worldwide contaminants, and they tend to accumulate in wide variety of matrices. Therefore, due to the highest accumulation rate and recalcitrancy, their precise quantification makes significant concern about their toxicological effects on both humans and organisms. The objective of the study is that using hydrogen carrier gas instead of helium in gas chromatography with triple quadrupole (GC-MS/MS) systems could contribute to improvements on the analysis of dl-PCBs and PCDD/Fs in environmental matrices.
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