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Man YB, Zhang F, Mo WY, Chow KL, Wong MH. Using food waste to cultivate safe, good-quality Sabah (giant hybrid) grouper: Dioxins and dioxin-like polychlorinated biphenyls. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 313:120122. [PMID: 36089147 DOI: 10.1016/j.envpol.2022.120122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 09/01/2022] [Accepted: 09/03/2022] [Indexed: 06/15/2023]
Abstract
Dioxins and dioxin-like polychlorinated biphenyls (dl-PCBs) in fish fillet counteract the health benefits of fish products. In this study, food waste was used as a protein alternative to replacing fishmeal commonly used in the commercial fish feed, aiming to cultivate Sabah grouper with acceptable levels of dioxins and dl-PCBs. The concentrations of dioxins and dl-PCBs, as well as the fish growth performance, were compared between the fish groups fed with food waste-based feed (FWBF) and commercial feed (Nanyu®, control). The results showed that the concentrations of polychlorinated dibenzo-p-dioxins (PCDDs) (1.22 pg/g dry weight (d.w.)) and non-ortho-dl-PCBs (13.0 pg/g d.w.) were significantly lower (p < 0.05) in the FWBF than in the control feed (commercial feed) (PCDDs: 2.35 pg/g d.w.; non-ortho-dl-PCBs: 27.2 pg/g d.w.). The growth performance of the fish group fed with the FWBF was comparable to that fed with the control feed. There were no significant differences between the WHO2005-TEQ values of different fish fillets (1.00, 1.11, and 1.10 pg WHO2005-TEQ/g d.w. for FWBF group, control feed group, and local market fish, respectively). Based on the guidelines provided by European Food Safety Authority (ESFA) and U.S. Environmental Protection Agency (USEPA), the fish fed with the FWBF were safe for human consumption (hazard index values: 0.284-0.522; cancer risk range: 2.59-2.97 × 10-5). The findings of this study suggest that food waste could serve as an alternative protein source for cultivating Sabah grouper with acceptable levels of dioxins and dl-PCBs.
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Affiliation(s)
- Yu Bon Man
- Consortium on Health, Environment, Education, and Research (CHEER), Department of Science and Environmental Studies, The Education University of Hong Kong, Tai Po, Hong Kong, PR China
| | - Feng Zhang
- Consortium on Health, Environment, Education, and Research (CHEER), Department of Science and Environmental Studies, The Education University of Hong Kong, Tai Po, Hong Kong, PR China
| | - Wing Yin Mo
- Department of Applied Science, School of Science and Technology, The Hong Kong Metropolitan University, Hong Kong, PR China
| | - Ka Lai Chow
- Department of Geography, Hong Kong Baptist University, Kowloon Tong, Hong Kong, PR China
| | - Ming Hung Wong
- Consortium on Health, Environment, Education, and Research (CHEER), Department of Science and Environmental Studies, The Education University of Hong Kong, Tai Po, Hong Kong, PR China.
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Sany SBT, Hashim R, Rezayi M, Rahman MA, Razavizadeh BBM, Abouzari-lotf E, Karlen DJ. Integrated ecological risk assessment of dioxin compounds. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2015; 22:11193-11208. [PMID: 25953606 DOI: 10.1007/s11356-015-4511-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Accepted: 04/07/2015] [Indexed: 06/04/2023]
Abstract
Current ecological risk assessment (ERA) schemes focus mainly on bioaccumulation and toxicity of pollutants in individual organisms. Ecological models are tools mainly used to assess ecological risks of pollutants to ecosystems, communities, and populations. Their main advantage is the relatively direct integration of the species sensitivity to organic pollutants, the fate and mechanism of action in the environment of toxicants, and life-history features of the individual organism of concern. To promote scientific consensus on ERA schemes, this review is intended to provide a guideline on short-term ERA involving dioxin chemicals and to identify key findings for exposure assessment based on policies of different agencies. It also presents possible adverse effects of dioxins on ecosystems, toxicity equivalence methodology, environmental fate and transport modeling, and development of stressor-response profiles for dioxin-like chemicals.
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Frawley R, DeVito M, Walker NJ, Birnbaum L, White K, Smith M, Maynor T, Recio L, Germolec D. Relative potency for altered humoral immunity induced by polybrominated and polychlorinated dioxins/furans in female B6C3F1/N mice. Toxicol Sci 2014; 139:488-500. [PMID: 24713691 DOI: 10.1093/toxsci/kfu041] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The use of brominated flame retardants and incineration of bromine-containing materials has lead to an increase in polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs) in the environment. Measurable amounts of PBDD/Fs have been detected in soil, seafood, and human breast milk and serum. Studies indicate that the relative potencies of some PBDD/Fs based on enzyme induction are equivalent to those of some polychlorinated dibenzo-p-dioxins and dibenzofurans. To assess the humoral immunity relative potencies of PBDD/Fs and compare them to their chlorinated analogs, female B6C3F1/N mice received a single oral exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), 2,3,7,8-tetrabromodibenzofuran (TBDF), 2,3,7,8-tetrachlorodibenzofuran (TCDF), 1,2,3,7,8-pentabromodibenzofuran (1PeBDF), 1,2,3,7,8-pentachlorodibenzofuran (1PeCDF), 2,3,4,7,8-pentabromodibenzofuran (4PeBDF), 2,3,4,7,8-pentachlorodibenzofuran (4PeCDF), 2,3-dibromo-7,8-dichlorodibenzo-p-dioxin (DBDCDD), or 2,3,7-tribromodibenzo-p-dioxin (TriBDD). Inhibition of the immunoglobulin M (IgM) antibody forming cell response was measured 4 days following immunization with sheep red blood cells. The data were fit to a Hill model to estimate the ED50 for inhibition. Expression of xenobiotic metabolizing enzyme (XME) and thyroxine transport protein (Ttr) genes in liver was measured by PCR to assess aryl hydrocarbon-mediated responses. TCDD, TBDF, TCDF, 1PeBDF, 4PeBDF, 4PeCDF, and DBDCDD suppressed the IgM antibody response and Ttr gene expression, and upregulated phase I XME genes. 1PeCDF suppressed the IgM antibody response but only upregulated phase I XME genes; TriBDD had no effect on antibody response. The rank order of potency (ED50) for these chemicals was TCDD>TBDF>4PeBDF>TCDF/4PeCDF/1PeBDF>1PeCDF. Whereas TCDD was the most potent compound tested, the brominated analogs were more potent than their chlorinated analogs, suggesting that these compounds should be considered in toxic equivalency factor evaluation and risk assessment.
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Affiliation(s)
- Rachel Frawley
- Division of the National Toxicology Program, National Institute of Environmental Health Sciences
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4
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Bursian SJ, Moore J, Newsted JL, Link JE, Fitzgerald SD, Bello N, Bhat VS, Kay D, Zhang X, Wiseman S, Budinsky RA, Giesy JP, Zwiernik MJ. Incidence of jaw lesions and activity and gene expression of hepatic P4501A enzymes in mink (Mustela vison) exposed to dietary 2,3,7,8-tetrachlorodibenzo-p-dioxin, 2,3,7,8-tetrachlorodibenzofuran, and 2,3,4,7,8-pentachlorodibenzofuran. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2012; 31:2545-2556. [PMID: 22865772 DOI: 10.1002/etc.1975] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2012] [Revised: 04/29/2012] [Accepted: 07/02/2012] [Indexed: 06/01/2023]
Abstract
This study assessed the effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), 2,3,4,7,8-pentachlorodibenzofuran (PeCDF), and 2,3,7,8 tetrachlorodibenzofuran (TCDF) on the incidence of jaw lesions and on hepatic cytochrome P4501A (CYP1A) endpoints in mink (Mustela vison). Adult female mink were assigned randomly to one of 13 dietary treatments (control and four increasing doses of TCDD, PeCDF, or TCDF) and provided spiked feed for approximately 150 d (60 d prior to breeding through weaning of offspring at 42 d post-parturition). Offspring were maintained on their respective diets for an additional 150 d. Activity of hepatic CYP1A enzymes in adult and juvenile mink exposed to TCDD, PeCDF, or TCDD was generally greater compared with controls, but changes in other CYP1A endpoints were less consistent. Histopathology of the mandible and maxilla of juvenile mink suggested a dose-related increase in the incidence of jaw lesions. The dietary effective doses (ED) for jaw lesions in 50% of the population (ED50) were estimated to be 6.6, 14, and 149 ng/kg body weight (bw)/d for TCDD, PeCDF, and TCDF, respectively. The relative potencies of PeCDF and TCDF compared with TCDD based on ED10, ED20, and ED50 values ranged from 0.5 to 1.9 and 0.04 to 0.09, respectively. These values are within an order of magnitude of the World Health Organization toxic equivalency factor (TEF(WHO)) values of 0.3 and 0.1 for PeCDF and TCDF, respectively.
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Affiliation(s)
- Steven J Bursian
- Department of Animal Science, Michigan State University, East Lansing, MI, USA.
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Seston RM, Giesy JP, Fredricks TB, Tazelaar DL, Coefield SJ, Bradley PW, Roark SA, Newsted JL, Kay DP, Zwiernik MJ. Dietary- and tissue-based exposure of belted kingfisher to PCDFs and PCDDs in the Tittabawassee River floodplain, Midland, MI, USA. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2012; 31:1158-1168. [PMID: 22362576 DOI: 10.1002/etc.1780] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2011] [Accepted: 12/23/2011] [Indexed: 05/31/2023]
Abstract
Concentrations of polychlorinated dibenzofurans (PCDFs) and other dioxin-like compounds in soils and sediments of the Tittabawassee River and associated floodplains downstream of Midland, Michigan, USA, are greater than upstream sites. As a result of these concentrations, which are some of the greatest ever reported, a site-specific exposure assessment of belted kingfisher breeding in the assessment area was conducted. To reduce the uncertainty associated with predicting exposure from abiotic matrices, concentrations of residues were quantified in site-specific prey items and in eggs and nestlings of belted kingfisher. Dietary exposure, expressed as the potential average daily dose, based on site-specific concentrations of PCDFs, polychlorinated dibenzo-p-dioxins (PCDDs), and 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (TEQ(WHO-Avian)) in prey items was consistently greater along the Tittabawassee River than in associated reference areas and further downstream sites in the Saginaw River. Concentrations of PCDD/DFs in eggs and nestlings of belted kingfisher varied among sampling areas, being greater in both eggs and nestlings nesting along the Tittabawassee River compared to those of belted kingfisher from upstream reference areas. Geometric mean concentrations of PCDD/DFs were 130 and 200 ng/kg wet weight in eggs and nestlings of belted kingfisher, respectively. These concentrations are the equivalent of 84 and 95 ng TEQ(WHO-Avian)/kg. Site-specific biomagnification factors for select PCDD/DF congeners ranged from <1.0 to 1.8 in belted kingfisher.
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Affiliation(s)
- Rita M Seston
- Department of Zoology, Center for Integrative Toxicology, Michigan State University, East Lansing, Michigan, USA.
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Moore JN, Zwiernik MJ, Newsted JL, Fitzgerald SD, Link JE, Bradley PW, Kay D, Budinsky R, Giesy JP, Bursian SJ. Effects of dietary exposure of mink (Mustela vison) to 2,3,7,8-tetrachlorodibenzo-p-dioxin, 2,3,4,7,8-pentachlorodibenzofuran, and 2,3,7,8-tetrachlorodibenzofuran on reproduction and offspring viability and growth. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2012; 31:360-369. [PMID: 22095843 DOI: 10.1002/etc.739] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2011] [Revised: 08/22/2011] [Accepted: 09/27/2011] [Indexed: 05/31/2023]
Abstract
This study assessed the effects of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), 2,3,4,7,8-pentachlorodibenzofuran (PeCDF), and 2,3,7,8-tetrachlorodibenzofuran (TCDF) on the reproductive performance of female mink (Mustela vison) and the viability and growth of their offspring. Nine adult female mink were randomly assigned to one of 13 dietary treatments (one control and four doses each of TCDD, PeCDF, and TCDF [2.1-8.4, 4.0-15 and 5.2-25 ng TCDD toxic equivalents (TEQ)/kg body wt/d]). Diets were fed from two months prior to breeding through weaning of offspring at six weeks of age. At least nine kits per treatment group were maintained on their diets through 27 weeks of age. There were no effects on litter size or viability of offspring. No consistent effects were observed on body mass or relative organ masses of animals at any age. 2,3,7,8-Tetrachlorodibenzo-p-dioxin and PeCDF accumulated in the liver and adipose tissue, but TCDF cleared rapidly. The lack of significant effects on reproduction and offspring viability contrasts with effects reported for mink exposed to environmentally derived PCB mixtures with equivalent TCDD potencies. This suggests that it may be inappropriate to apply toxicity reference values associated with PCB mixtures to animals also exposed to TCDD, PeCDF, or TCDF, and the World Health Organization TCDD toxic equivalency factors for some congeners may not be appropriate for mink.
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Affiliation(s)
- Jeremy N Moore
- Department of Animal Science, Michigan State University, East Lansing, Michigan, USA
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Fredricks TB, Zwiernik MJ, Seston RM, Coefield SJ, Tazelaar DL, Roark SA, Kay DP, Newsted JL, Giesy JP. Effects on tree swallows exposed to dioxin-like compounds associated with the Tittabawassee River and floodplain near Midland, Michigan, USA. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2011; 30:1354-1365. [PMID: 21360578 DOI: 10.1002/etc.511] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/25/2010] [Revised: 09/23/2010] [Accepted: 01/02/2011] [Indexed: 05/30/2023]
Abstract
Concentrations of dioxin-like compounds, primarily polychlorinated dibenzofurans (PCDFs) and polychlorinated dibenzo-p-dioxins (PCDDs), in soils and sediments downstream of Midland, Michigan (USA) were greater than upstream sites and prompted a site-specific hazard assessment of tree swallows breeding in the associated floodplains. Potential for adverse population-level effects from site-specific contaminant exposures were evaluated at study areas (SAs) along the Tittabawassee and Saginaw rivers downstream of Midland. The site-specific multiple lines of evidence approach to hazard assessment included endpoints for dietary- and tissue-based exposures, and population productivity measurements for tree swallows ([TS]; Tachycineta bicolor) measured during the 2005, 2006, and 2007 breeding seasons. Exposure to dioxin-like compounds in TS eggs were some of the greatest recorded and were similar among all upstream and downstream study sites. Conversely, concentrations in nestlings from SAs were significantly greater compared to reference areas (RAs). The pattern of relative concentrations of PCDD/DFs in eggs and nestlings at RAs was dominated by dioxin congeners, whereas at SAs it was dominated by furan congeners. No statistically significant differences were noted in exposure to PCDD/DFs or in population-level responses when compared among locations, and total clutch failures were rare. Hatching success and fledging success were weakly negatively correlated with concentrations of 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (TEQs) in individual eggs and nestlings, respectively. On-site concentrations of TEQs in floodplain soils were some of the greatest ever reported in the environment, and several lines of evidence indicate potential population-level effects on TS overall reproductive productivity.
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Seston RM, Fredricks TB, Tazelaar DL, Coefield SJ, Bradley PW, Roark SA, Newsted JL, Kay DP, Zwiernik MJ, Giesy JP. Dietary exposure of great blue heron (Ardea herodias) to PCDD/DFs in the Tittabawassee River floodplain, MI, USA. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2011; 74:494-503. [PMID: 21093913 DOI: 10.1016/j.ecoenv.2010.10.024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2010] [Revised: 10/12/2010] [Accepted: 10/14/2010] [Indexed: 05/30/2023]
Abstract
Concentrations of dioxin-like compounds, primarily polychlorinated dibenzofurans (PCDFs), in soils and sediments of the Tittabawassee River (TR) and associated floodplains downstream of Midland, Michigan (USA) were greater than upstream sites and prompted a site-specific risk assessment of great blue herons (GBH). Dietary exposure of GBH to PCDFs and polychlorinated dibenzo-p-dioxins (PCDDs) was evaluated based on site-specific concentrations of residues in prey items. Concentrations of ∑PCDD/DFs and 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (TEQ(WHO-Avian)) in prey items collected from the TR were consistently greater than those collected from associated reference areas (RAs) and further downstream in the Saginaw River (SR). The average daily dose (ADD(pot)) of ∑PCDD/DFs to GBH was 45- to 54-fold greater along the TR and 12-fold greater along the SR when compared to the RA. ∑PCDD/DFs were normalized to TEQ(WHO-Avian), and fold differences in the ADD(pot) increased, being 150- to 190-fold greater along the TR and 36-fold greater along the SR than they were in the RA. Greater fold changes in the ADD(pot) based on TEQ(WHO-Avian) between the RA and the TR and SR was due to prey items from the latter reaches having a greater relative toxic potency of ∑PCDD/DFs, primarily from greater amounts of 2,3,7,8-tetrachlorodibenzofuran but also 2,3,4,7,8-pentachlorodibenzofuran. Potential for adverse population-level effects from site-specific contaminant exposures were evaluated via comparison to selected toxicity reference values. The prediction of minimal to no risk of adverse population-level effects resultant from the assessment of site-specific dietary exposure of GBH to ∑PCDD/DFs along the TR and SR is consistent with site-specific assessments of tissue-based exposures as well as population condition.
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Affiliation(s)
- Rita M Seston
- Department of Zoology, Center for Integrative Toxicology, 3270 Anthony Hall, Michigan State University, East Lansing, MI 48824, USA.
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Seston RM, Fredricks TB, Tazelaar DL, Coefield SJ, Bradley PW, Newsted JL, Kay DP, Fitzgerald SD, Giesy JP, Zwiernik MJ. Tissue-based risk assessment of great blue heron (Ardea herodias) exposed to PCDD/DF in the Tittabawassee River floodplain, Michigan, USA. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2010; 29:2544-2558. [PMID: 20886642 DOI: 10.1002/etc.319] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Concentrations of dioxin-like compounds, primarily polychlorinated dibenzofurans (PCDFs), in soils and sediments of the Tittabawassee River (TR) and associated floodplains downstream of Midland, Michigan, USA, were greater than upstream sites and prompted a site-specific risk assessment of great blue herons (GBH). Tissue exposure of PCDF and polychlorinated dibenzo-p-dioxins (PCDDs) was assessed in multiple GBH tissue types, including blood plasma of adults and eggs, as well as blood plasma, adipose, liver, and muscle of nestlings. Adult GBH exposure was associated with foraging area and age class, with concentrations of PCDD/DF being greater in blood plasma of adult GBH foraging in the TR compared with those foraging in upstream reference areas and in older birds as compared with their younger cohorts. Concentrations of PCDD/DFs and dioxin-like polychlorinated biphenyls (PCBs) in eggs and nestling tissues of GBH collected from rookeries within the TR floodplain were generally similar among rookeries. Mean concentrations of PCDD/DFs in eggs of GBH ranged from 45 to 67 ng/kg, wet weight for the rookeries studied, with a maximum concentration of 210 ng/kg, wet weight observed. Adipose consistently had the greatest concentration of PCDD/DFs of all tissues collected from nestlings of GBH, ranging from 98 to 430 ng/kg, wet weight. Potential for adverse population-level effects from site-specific contaminant exposures were evaluated by comparison with selected toxicity reference values (TRVs). Minimal risk of adverse population-level effects were predicted when exposures measured in tissues of GBH collected from rookeries within the TR were compared with appropriate TRVs. This prediction is consistent with site-specific measures of population condition, which included clutch size and number of nestlings per successful nest.
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Affiliation(s)
- Rita M Seston
- Department of Zoology, Center for Integrative Toxicology, Michigan State University, East Lansing, Michigan 48824, USA.
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Budinsky RA, LeCluyse EL, Ferguson SS, Rowlands JC, Simon T. Human and rat primary hepatocyte CYP1A1 and 1A2 induction with 2,3,7,8-tetrachlorodibenzo-p-dioxin, 2,3,7,8-tetrachlorodibenzofuran, and 2,3,4,7,8-pentachlorodibenzofuran. Toxicol Sci 2010; 118:224-35. [PMID: 20705892 DOI: 10.1093/toxsci/kfq238] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The concentration dose response for aryl hydrocarbon receptor (AHR)-mediated CYP1A1 and CYP1A2 messenger RNA (mRNA) induction and enzyme activity was determined in primary cultures of rat and human hepatocytes for 2,3,7,8-tetrachlorodibenzo-p-dioxin, 2,3,4,7,8-pentachlorodibenzofuran, and 2,3,7,8-tetrachlorodibenzofuran. Eleven different congener concentrations from 0.00001 to 100 nM were used, thus spanning seven orders of magnitude. The Hill model was used to obtain values of EC(x) and maximal response from the individual data sets. No-observed effect concentration values were derived using several statistical methods including Dunnett's test, the Welch-Aspin test, and step-down bilinear regression. Thresholds were estimated using baseline projection methods and a "hockey stick" fitting method. Human hepatocytes were less responsive and less sensitive with respect to CYP1A1 activity and mRNA induction than rats. On the other hand, the human CYP1A2 response was more robust than the response in rats but generally less sensitive. These data allow an evaluation of relative species sensitivities for developing interspecies toxicodynamic adjustment factors, for assessing AHR activation thresholds, and for evaluating relative congener potencies. Overall, these data support the position that humans are less sensitive than rats to these AHR-dependent end points and support the use of a data-derived adjustment factor of 1.0 or less for extrapolating between rats and humans.
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Burgoon LD, Ding Q, N'jai A, Dere E, Burg AR, Rowlands JC, Budinsky RA, Stebbins KE, Zacharewski TR. Automated dose-response analysis of the relative hepatic gene expression potency of TCDF in C57BL/6 mice. Toxicol Sci 2009; 112:221-8. [PMID: 19675144 DOI: 10.1093/toxsci/kfp180] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
Toxic equivalency factors (TEFs) are assigned to dioxin-like chemicals based on relative potency (REP) values of individual adaptive and toxic responses compared to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Agilent 4x44K oligonucleotide microarrays were used to examine the hepatic gene expression potency of 2,3,7,8-tetrachlorodibenzofuran (TCDF), relative to TCDD with complementary histopathology, TCDD and TCDF tissue level analysis, and ethoxyresorufin-O-deethylase (EROD) assay data. Immature ovariectomized C57BL/6 mice were gavaged with 0.03, 0.1, 0.3, 1, 3, 10, 30, or 100 microg/kg TCDD, the World Health Organization TEF-adjusted doses (10 x TCDD dose) of TCDF (0.3, 1, 3, 10, 30, 100, or 300 microg/kg), or sesame oil vehicle and killed at 72 h. Two thousand two hundred eighty-eight and 1347 genes were differentially expressed (P1(t) > 0.90) at one or more doses by TCDD and TCDF, respectively. Automated dose-response modeling (ToxResponse Modeler) identified a total of 1027 and 837 genes with either a sigmoidal, exponential, linear, Gaussian, or quadratic dose-response relationship 72 h after treatment in TCDD and TCDF, respectively. Two hundred seventy genes exhibited a sigmoidal TCDD-induced dose-response (ED(50s) from 0.08 to 42.2 microg/kg) compared to only 179 sigmoidal responsive genes (ED(50s) from 0.74 to 299.9 microg/kg) elicited by TCDF. Of the 1027 TCDD dose-responsive genes, 654 were not examined further due to the lack of a dose response elicited by TCDF. Of the 373 genes that exhibited a TCDD and TCDF dose response, REPs were calculated for the 83 genes that exhibited comparable sigmoidal curve shapes and slopes. The median REP for these 83 genes was 0.10, with a maximum REP of 0.56 and a minimum of 0.01. REPs of 0.04 were also calculated for EROD and increase in relative liver weight (RLW) at 72 h. Collectively, the lower number of TCDF-induced genes compared to TCDD and the 0.04 REPs for EROD activity and increased RLW are not consistent with the TEF of 0.10 for the hepatotoxicity of TCDF in C57BL/6 mice at 72 h.
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Affiliation(s)
- Lyle D Burgoon
- Department of Biochemistry & Molecular Biology, Michigan State University, 501 Biochemistry Building, Wilson Road, East Lansing, MI 48824-1319, USA
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Moore JN, Newsted JL, Hecker M, Zwiernik MJ, Fitzgerald SD, Kay DP, Zhang X, Higley EB, Aylward LL, Beckett KJ, Budinsky RA, Bursian SJ, Giesy JP. Hepatic P450 enzyme activity, tissue morphology and histology of mink (Mustela vison) exposed to polychlorinated dibenzofurans. ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2009; 57:416-425. [PMID: 19458992 PMCID: PMC2700875 DOI: 10.1007/s00244-008-9241-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/22/2008] [Accepted: 09/08/2008] [Indexed: 05/27/2023]
Abstract
Dose- and time-dependent effects of environmentally relevant concentrations of 2,3,7,8-tetrachlorodibenzo-p-dioxin equivalents (TEQ) of 2,3,7,8-tetrachlorodibenzofuran (TCDF), 2,3,4,7,8-pentachlorodibenzofuran (PeCDF), or a mixture of these two congeners on hepatic P450 enzyme activity and tissue morphology, including jaw histology, of adult ranch mink were determined under controlled conditions. Adult female ranch mink were fed either TCDF (0.98, 3.8, or 20 ng TEQ(TCDF)/kg bw/day) or PeCDF (0.62, 2.2, or 9.5 ng TEQ(PeCDF)/kg bw/day), or a mixture of TCDF and PeCDF (4.1 ng TEQ(TCDF)/kg bw/day and 2.8 ng TEQ(PeCDF)/kg bw/day, respectively) for 180 days. Doses used in this study were approximately eight times greater than those reported in a parallel field study. Activities of the cytochrome P450 1A enzymes, ethoxyresorufin O-deethylase (EROD) and methoxyresorufin O-deethylase (MROD) were significantly greater in livers of mink exposed to TCDF, PeCDF, and a mixture of the two congeners; however, there were no significant histological or morphological effects observed. It was determined that EROD and MROD activity can be used as sensitive biomarkers of exposure to PeCDF and TCDF in adult female mink; however, under the conditions of this study, the response of EROD/MROD induction occurred at doses that were less than those required to cause histological or morphological changes.
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Affiliation(s)
- Jeremy N. Moore
- Department of Zoology, National Food Safety and Toxicology Center, Michigan State University, East Lansing, MI 48824 USA
- Department of Animal Science, Center for Integrative Toxicology, Michigan State University, East Lansing, MI 48824 USA
| | - John L. Newsted
- Department of Animal Science, Center for Integrative Toxicology, Michigan State University, East Lansing, MI 48824 USA
- ENTRIX, Inc., Okemos, MI 48823 USA
| | - Markus Hecker
- Department of Biomedical Veterinary Sciences and Toxicology Centre, University of Saskatchewan, Saskatoon, SK Canada S7N 5B3
- ENTRIX, Inc., Saskatoon, SK Canada S7N 5B3
| | - Matthew J. Zwiernik
- Department of Zoology, National Food Safety and Toxicology Center, Michigan State University, East Lansing, MI 48824 USA
- Department of Animal Science, Center for Integrative Toxicology, Michigan State University, East Lansing, MI 48824 USA
| | - Scott D. Fitzgerald
- Department of Pathobiology and Diagnostic Investigation, Diagnostic Center for Population and Animal Health, Michigan State University, East Lansing, MI 48824 USA
| | | | - Xiaowei Zhang
- Department of Zoology, National Food Safety and Toxicology Center, Michigan State University, East Lansing, MI 48824 USA
| | - Eric B. Higley
- Department of Zoology, National Food Safety and Toxicology Center, Michigan State University, East Lansing, MI 48824 USA
| | | | | | | | - Steven J. Bursian
- Department of Animal Science, Center for Integrative Toxicology, Michigan State University, East Lansing, MI 48824 USA
| | - John P. Giesy
- Department of Zoology, National Food Safety and Toxicology Center, Michigan State University, East Lansing, MI 48824 USA
- Department of Biomedical Veterinary Sciences and Toxicology Centre, University of Saskatchewan, Saskatoon, SK Canada S7N 5B3
- Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong SAR China
- School of Environment, Nanjing University, Nanjing, 210093 China
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Sequencing and characterization of mixed function monooxygenase genes CYP1A1 and CYP1A2 of Mink (Mustela vison) to facilitate study of dioxin-like compounds. Toxicol Appl Pharmacol 2009; 234:306-13. [DOI: 10.1016/j.taap.2008.10.017] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2008] [Revised: 10/20/2008] [Accepted: 10/20/2008] [Indexed: 11/21/2022]
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14
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Zwiernik MJ, Moore JN, Khim JS, Williams LL, Kay DP, Bursian S, Aylward LL, Giesy JP. Nondestructive scat sampling in assessment of mink (Mustela vison) exposed to polychlorinated dibenzofurans (PCDFs). ARCHIVES OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2008; 55:529-537. [PMID: 18227958 DOI: 10.1007/s00244-007-9131-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2007] [Accepted: 12/27/2007] [Indexed: 05/25/2023]
Abstract
The mink (Mustela vison) is often utilized as a sentinel species for ecological assessments at sites where contaminants of concern include dioxins and dioxin-like compounds. Utilizing mink scat as a nondestructive tool to determine internal exposure to dioxin-like compounds may allow for rapid, accurate estimates of exposure without the need to capture mink or their prey. To determine the relationships between concentrations of polychlorinated dibenzofurans (PCDFs) in tissues (liver and adipose) and those in scat, mink were fed PCDFs in scat during a controlled laboratory study for 180 days. Mink were fed a control diet, diets with three doses of 2,3,4,7,8-pentachlorodibenzofuran (2,3,4,7,8-PeCDF) or 2,3,7,8-tetrachlorodibenzofuran (2,3,7,8-TCDF), and a diet with an environmentally relevant mixture of the two congeners. Concentrations of PCDFs in liver and adipose were measured after 0, 90, and 180 days of exposure. Concentrations of the two PCDF congeners in mink scat were determined after 2, 23, 45, 90, and 180 days of exposure. Concentrations of both PCDF congeners in scat were significantly correlated with those in liver and adipose tissue (r(2) = 0.94-0.97, p < 0.01). This indicates that measurements of concentrations of both PCDFs in scat can be used to predict concentrations of PCDFs in liver and adipose. Assimilation and elimination characteristics of 2,3,4,7,8-PeCDF or 2,3,7,8,-TCDF and a mixture of the two congeners by mink could be predicted from concentrations of these congeners in scat. Overall, concentrations of PCDFs in mink scat can be used as a rapid and inexpensive nondestructive method to predict concentrations of PCDFs in mink when certain assumptions are met.
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Affiliation(s)
- Matthew J Zwiernik
- Zoology Department, Center for Integrative Toxicology, National Food Safety and Toxicology Center, Michigan State University, East Lansing, MI 48824, USA
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