Health & Environmental Research Online (HERO)


Benzo(a)pyrene (BaP)


1,857 References Were Found:

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Chronic Administration of Benzo(a)pyrene Induces Memory Impairment and Anxiety-Like Behavior and Increases of NR2B DNA Methylation

Authors: Zhang, W; Tian, F; Zheng, J; Li, S; Qiang, Mei (2016) PLoS ONE 11:e0149574. HERO ID: 3123894

[Less] BACKGROUND: Recently, an increasing number of human and animal studies have reported . . . [More] BACKGROUND: Recently, an increasing number of human and animal studies have reported that exposure to benzo(a)pyrene (BaP) induces neurological abnormalities and is also associated with adverse effects, such as tumor formation, immunosuppression, teratogenicity, and hormonal disorders. However, the exact mechanisms underlying BaP-induced impairment of neurological function remain unclear. The aim of this study was to examine the regulating mechanisms underlying the impact of chronic BaP exposure on neurobehavioral performance.

METHODS: C57BL mice received either BaP in different doses (1.0, 2.5, 6.25 mg/kg) or olive oil twice a week for 90 days. Memory and emotional behaviors were evaluated using Y-maze and open-field tests, respectively. Furthermore, levels of mRNA expression were measured by using qPCR, and DNA methylation of NMDA receptor 2B subunit (NR2B) was examined using bisulfate pyrosequencing in the prefrontal cortex and hippocampus.

RESULTS: Compared to controls, mice that received BaP (2.5, 6.25 mg/kg) showed deficits in short-term memory and an anxiety-like behavior. These behavioral alterations were associated with a down-regulation of the NR2B gene and a concomitant increase in the level of DNA methylation in the NR2B promoter in the two brain regions.

CONCLUSIONS: Chronic BaP exposure induces an increase in DNA methylation in the NR2B gene promoter and down-regulates NR2B expression, which may contribute to its neurotoxic effects on behavioral performance. The results suggest that NR2B vulnerability represents a target for environmental toxicants in the brain.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Western diet enhances benzo(a)pyrene-induced colon tumorigenesis in a Polyposis In Rat Coli (PIRC) rat model of colon cancer

Authors: Harris, KL; Pulliam, SR; Okoro, E; Guo, Z; Washington, MK; Adunyah, SE; Amos-Landgraf, JM; Ramesh, A (2016) Oncotarget 7:28947-28960. HERO ID: 3121803

[Less] Consumption of Western diet (WD), contaminated with environmental toxicants, has been implicated as . . . [More] Consumption of Western diet (WD), contaminated with environmental toxicants, has been implicated as one of the risk factors for sporadic colon cancer. Our earlier studies using a mouse model revealed that compared to unsaturated dietary fat, the saturated dietary fat exacerbated the development of colon tumors caused by B(a)P. The objective of this study was to study how WD potentiates B(a)P-induced colon carcinogenesis in the adult male rats that carry a mutation in the Apc locus - the polyposis in rat colon (PIRC) rats. Groups of PIRC rats were fed with AIN-76A standard diet (RD) or Western diet (WD) and received 25, 50, or 100 μg B(a)P/kg body weight (wt) via oral gavage for 60 days. Subsequent to exposure, rats were euthanized; colons were retrieved and preserved in 10% formalin for counting the polyp numbers, measuring the polyp size, and histological analyses. Blood samples were collected and concentrations of cholesterol, triglycerides, glucose, insulin and leptin were measured. Rats that received WD + B(a)P showed increased levels of cholesterol, triglycerides, and leptin in comparison to RD + B(a)P groups or controls. The colon tumor numbers showed a B(a)P dose-response relationship. Adenomas with high grade dysplasia were prominent in B(a)P + WD rats compared to B(a)P + RD rats and controls (p < 0.05). The larger rat model system used in this study allows for studying more advanced tumor phenotypes over a longer duration and delineating the role of diet - toxicant interactions in sporadic colon tumor development.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Testicular and epididymal toxicity induced by benzo(a) pyrene, alcohol, and their combination in Wistar rats

Authors: Reddy, KP; Reddy, PS (2016) Toxicology Research 5:420-433. HERO ID: 3123583

[Less] Alcoholism and cigarette smoking are pervasive problems that have been implicated in human health. In . . . [More] Alcoholism and cigarette smoking are pervasive problems that have been implicated in human health. In this study, independent and combinative toxicities of alcohol and benzo(a) pyrene (BaP) were tested for reproductive toxicity in rats. Male Wistar rats were exposed to BaP (100 mu g per kg body weight) on alternative days and alcohol (2 g per kg body weight per day) daily, either individually or in combination for 60 days. Exposure to BaP or alcohol significantly decreased the fertility index and reduced the number of implantations associated with elevated pre- and post-implantation losses. The relative weights of testes, epididymis, seminal vesicles, and prostate gland were significantly decreased in BaP or alcohol administered rats. Exposure to BaP or alcohol significantly decreased daily sperm production, sperm density, percentages of motile, viable, HOS-tail swelled sperm, testicular 3 beta- and 17 beta-hydroxysteroid dehydrogenase activity levels, mRNA levels of steroidogenic acute regulatory protein, and serum testosterone levels. Further, in silico studies revealed the binding of BaP at the hydrophobic tunnel of StAR protein. Additional studies disclosed stable interactions of BaP with the amide group of ASN150 and the hydroxyl group of THR263 by forming three hydrogen bonds. Our results also showed that treatment of rats with BaP or alcohol caused a marked increase in levels of superoxide anions, hydrogen peroxide, and lipid peroxidation in testis and epididymis. Conversely, glutathione levels and activity levels of superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase in testis as well as epididymis decreased significantly in the experimental rats. Under the same conditions, increased fragmented DNA levels were observed in sperm. The results of the present study indicate that exposure to BaP or alcohol adversely affected the male reproductive functions, which may be, at least in part, due to androgen deficiency and/or oxidative stress-related mechanisms. Consistently, the present results also showed higher reproductive toxicity upon exposure to combinations of BaP and alcohol than upon their individual treatments. Therefore, this combination was classified as additive and synergistic responses of BaP and alcohol.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Polycyclic aromatic hydrocarbons: determinants of residential carpet dust levels and risk of non-Hodgkin lymphoma

Authors: Dellavalle, CT; Deziel, NC; Jones, RR; Colt, JS; De Roos, AJ; Cerhan, JR; Cozen, W; Severson, RK; Flory, AR; Morton, LM; Ward, MH (2016) Cancer Causes and Control 27:1-13. HERO ID: 3124204

[Less] PURPOSE: To investigate the risk of non-Hodgkin lymphoma (NHL) associated with residential . . . [More] PURPOSE: To investigate the risk of non-Hodgkin lymphoma (NHL) associated with residential carpet dust measurements of polycyclic aromatic hydrocarbons (PAHs).

METHODS: We evaluated the relationship between residential carpet dust PAH concentrations (benz(a)anthracene, benzo(a)pyrene, benzo(b)fluoranthene, benzo(k)fluoranthene, chrysene, dibenz(a,h)anthracene, and indeno(1,2,3-c,d)pyrene, and their sum) and risk of NHL (676 cases, 511 controls) in the National Cancer Institute Surveillance Epidemiology and End Results multicenter case-control study. As a secondary aim, we investigated determinants of dust PAH concentrations. We computed odds ratios (OR) and 95 % confidence interval (CI) for associations between NHL and concentrations of individual and summed PAHs using unconditional logistic regression, adjusting for age, gender, and study center. Determinants of natural log-transformed PAHs were investigated using multivariate least-squares regression.

RESULTS: We observed some elevated risks for NHL overall and B cell lymphoma subtypes in association with quartiles or tertiles of PAH concentrations, but without a monotonic trend, and there was no association comparing the highest quartile or tertile to the lowest. In contrast, risk of T cell lymphoma was significantly increased among participants with the highest tertile of summed PAHs (OR = 3.04; 95 % CI, 1.09-8.47) and benzo(k)fluoranthene (OR = 3.20; 95 % CI, 1.13-9.11) compared with the lowest tertile. Predictors of PAH dust concentrations in homes included ambient air PAH concentrations and the proportion of developed land within 2 km of a residence. Older age, more years of education, and white race were also predictive of higher levels in homes.

CONCLUSION: Our results suggest a potential link between PAH exposure and risk of T cell lymphoma and demonstrate the importance of analyzing risk by NHL histologic type.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Altered expression of histone deacetylases, inflammatory cytokines and contractile-associated factors in uterine myometrium of Long Evans rats gestationally exposed to benzo[a]pyrene

Authors: Laknaur, A; Foster, TL; Bobb, LE; Ramesh, A; Ladson, GM; Hood, DB; Al-Hendy, A; Thota, C (2016) Journal of Applied Toxicology 36:827-835. HERO ID: 3224992

[Less] Etiology of preterm birth (PTB) is multifactorial; therefore, decreasing the incidence of PTB is a major . . . [More] Etiology of preterm birth (PTB) is multifactorial; therefore, decreasing the incidence of PTB is a major challenge in the field of obstetrics. Epidemiological studies have reported an association between toxicants and PTB. However, there are no studies on the role of benzo[a]pyrene (BaP), an environmental toxicant, in the incidence of PTB. We first assessed the effects of BaP (150 and 300 µg kg(-1) body weight) dosed via gavage from day 14 to 17 of pregnancy on gestation length in Long Evans rats. We further assessed the histopathology of the uterus, expression of inflammatory cytokines, contractile-associated factors, histone deacetylases (HDACs) and NFқB-p65 in myometrium collected on day 22 postpartum versus vehicle-treated controls. In our study, rats exposed to BaP delivered prematurely (P < 0.05) compared to control. Hematoxylin and eosin staining of uterus showed squamous metaplasia, glandular and stromal hyperplasia in BaP-exposed rats versus control. The concentrations of BaP metabolites measured by high-pressure liquid chromatography were higher in uterine myometrium of BaP-exposed rats while they were undetectable in controls. Quantitative real-time polymerase chain reaction showed significant increases in mRNA expression of interleukin-1β and -8, tumor necrosis factor-α, connexin 43, cyclo-oxygenase-2 and prostaglandin F2α receptor as compared to controls (P < 0.05). Western blot analysis revealed that BaP exposure caused decreases in class I HDACs 1 and 3 and increases in class II HDAC 5, cyclo-oxygenase-2 and nuclear translocation of NFκB-p65 relative to controls. Our results suggest that gestational exposure to BaP increases incidence of PTB through epigenetic changes that causes increases in the expression of contractile-associated factors through the NFκB pathway. Copyright © 2015 John Wiley & Sons, Ltd.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Subchronic exposure of benzo(a)pyrene interferes with the expression of Bcl-2, Ki-67, C-myc and p53, Bax, Caspase-3 in sub-regions of cerebral cortex and hippocampus

Authors: He, J; Ji, X; Li, Y; Xue, X; Feng, G; Zhang, H; Wang, H; Gao, M (2016) Experimental and Toxicologic Pathology 68:149-156. HERO ID: 3160685

[Less] Benzo[a]pyrene [B(a)P], a representative substance of the polycyclic aromatic hydrocarbons, is an ubiquitous . . . [More] Benzo[a]pyrene [B(a)P], a representative substance of the polycyclic aromatic hydrocarbons, is an ubiquitous environmental contaminant. However, the mechanism of B(a)P neurotoxicity is still not clear. The aim of this study was to investigate the molecular mechanism by assay the expression of Bcl-2, C-myc, Ki-67 oncogene and p53, Bax, Caspase-3 proapoptotic gene in sub-regions of cerebral cortex and hippocampus in brain. Mice were administrated with subchronic intraperitoneal injection and oral gavage of B(a)P (2.5, 5, 10mg/kg body weight) for 13 weeks. We observed that B(a)P induced the significant increase in relative brain weights and the slight proliferation phenomenon in hippocampus in the experiment. Significant increase of C-myc, Ki-67 and p53, Bax, Caspase-3 and dramatic decrease of Bcl-2 protein levels were observed through immunohistochemical analysis. The relative higher interference of Bcl-2, C-myc, Ki-67 and p53, Bax, Caspase-3 proteins was observed in hippocampus sub-regions of dentate gyrus, cornu ammonis 3 and cornu ammonis 1. The relative lower interference of the examined genes was found in cerebral cortex sub-regions of frontal cortex, temporal cortex and parietal cortex. The results showed a region-difference manner with accompanying dose-dependent manner in brain hippocampus and cerebral cortex induced by B(a)P. These findings indicate that B(a)P-induced subchronic neural toxicity may occur through the enhancement in Bcl-2, C-myc, Ki-67 oncogenes and p53, Bax, Caspase-3 proapoptotic genes expression.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Association of environmental benzo[a]pyrene exposure and DNA methylation alterations in hepatocellular carcinoma: A Chinese case-control study

Authors: Tian, M; Zhao, B; Zhang, Jie; Martin, FL; Huang, Q; Liu, L; Shen, H (2016) Science of the Total Environment 541:1243-1252. HERO ID: 3124556

[Less] Epidemiological studies implicate environmental risk factors and epigenetic alterations in the multistage . . . [More] Epidemiological studies implicate environmental risk factors and epigenetic alterations in the multistage process of hepatocellular carcinoma (HCC) development. However, associations between environmental factors and DNA methylation of tumour suppressor genes (TSGs) in HCC development remain ambiguous. Understanding how possible interactions influence risk may provide insights into the complexity of hepato-carcinogenesis. For this study, blood samples were collected from HCC patients (n=90) and healthy volunteers (n=99) from Xiamen (China) and data for selected environmental risk factors [e.g., benzo[a]pyrene (B[a]P), hepatitis B or C virus (HBV or HCV) infection, smoking and alcohol consumption] were recorded; factors identified as significantly higher (P<0.05) amongst case subjects compared to controls were identified. In order to assess associations for epigenetic alterations and HCC risk factors, serum DNA methylation of TSGs was quantified using high-resolution melting (HRM) analysis. Our results clearly indicate elevated methylation patterns for detoxification gene [glutathione-S-transferase Pi (GSTP)] promoter regions in cases compared to control subjects. Additionally, GSTP promoter hypermethylation and B[a]P diol epoxide-albumin (BPDE-Alb) were positively correlated with HCC incidence. Our epidemiological and in vitro cell model studies indicated that GSTP promoter DNA methylation regulates this gene's expression. Moreover, GSTP also plays an important role in B[a]P detoxification and potential protective role against B[a]P-induced liver cell toxicity and hepato-carcinogenesis.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Low-dose benzo[a]pyrene aggravates allergic airway inflammation in mice

Authors: Yanagisawa, R; Koike, E; Win-Shwe, TT; Ichinose, T; Takano, H (2016) Journal of Applied Toxicology 36:1496-1504. HERO ID: 3121875

[Less] Benzo[a]pyrene (BaP) reportedly has mutagenic and adjuvant activities. We aimed to determine the effects . . . [More] Benzo[a]pyrene (BaP) reportedly has mutagenic and adjuvant activities. We aimed to determine the effects of low-dose BaP administration on allergic airway inflammation and mediastinal lymph node (MLN) cell activation/proliferation in mice. Male C3H/HeJ mice were intratracheally administered ovalbumin (OVA) every 2 weeks and/or BaP (0, 0.05, 1 and 20 pmol per animal per week) once per week for 6 weeks. The cellular profile of bronchoalveolar lavage (BAL) fluid, histological changes, inflammatory cytokines/chemokines in the lungs, OVA-specific immunoglobulin (Ig) in serum and MLN cell activation/proliferation were examined. BaP administration of 20 pmol with OVA enhanced neutrophil and macrophage accumulation in the lungs. Compared with OVA administration, BaP administration with OVA tended to enhance pulmonary eosinophilia and goblet cell hyperplasia. Furthermore, it increased the levels of interleukin (IL)-5, IL-13, IL-33, monocyte chemoattractant protein-1 and eotaxin in the lungs, and OVA-specific IgG1 in serum, although not dose-dependently. Compared with the vehicle group, IL-6 and tumor necrosis factor-alpha levels were higher in the OVA + 1 pmol BaP group and IL-12 production was higher in the OVA + 20 pmol BaP group. Ex vivo studies showed that co-exposure to OVA and BaP activated the MHC class II and CD86 expression in MLN cells. Exposure to BaP with OVA increased IL-4, IL-5 and interferon gamma levels in culture supernatants of OVA-re-stimulated MLN cells. In conclusion, low-dose BaP can, at least in part, enhance allergic airway inflammation by facilitating Th2 responses and activating MLN cells; a high BaP dose may contribute to activating both Th1 and Th2 responses. Copyright © 2016 John Wiley & Sons, Ltd.

The "refereed" or "peer review" status of a journal comes from the Ulrichsweb Global Serials Directory (http://ulrichsweb.serialssolutions.com/), as supplied by the publisher. The term refers to the system of critical evaluation of manuscripts/articles by professional colleagues or peers. The content of refereed publications is sanctioned, vetted, or otherwise approved by a peer-review or editorial board. The peer-review and evaluation system is utilized to protect, maintain, and raise the quality of scholarly material published in serials. Publications subject to the referee process are assumed, then, to contain higher quality content than those that are not.
Peer Reviewed Journal Article

Dose-response modeling with summary data from developmental toxicity studies

Authors: Fox, JR; Hogan, KA; Davis, A (2016) Risk Analysis. HERO ID: 3392311

[Less] Dose-response analysis of binary developmental data (e.g., implant loss, fetal abnormalities) is best . . . [More] Dose-response analysis of binary developmental data (e.g., implant loss, fetal abnormalities) is best done using individual fetus data (identified to litter) or litter-specific statistics such as number of offspring per litter and proportion abnormal. However, such data are not often available to risk assessors. Scientific articles usually present only dose-group summaries for the number or average proportion abnormal and the total number of fetuses. Without litter-specific data, it is not possible to estimate variances correctly (often characterized as a problem of overdispersion, intralitter correlation, or “litter effect”). However, it is possible to use group summary data when the design effect has been estimated for each dose group. Previous studies have demonstrated useful dose-response and trend test analyses based on design effect estimates using litter-specific data from the same study. This simplifies the analysis but does not help when litter-specific data are unavailable. In the present study, we show that summary data on fetal malformations can be adjusted satisfactorily using estimates of the design effect based on historical data. When adjusted data are then analyzed with models designed for binomial responses, the resulting benchmark doses are similar to those obtained from analyzing litter-level data with nested dichotomous models.

Technical Report
Technical Report

Benzo[a]pyrene in drinking water (Draft)

Author: Health Canada (2015) Ottawa, Ontario: Health Canada. HERO ID: 2927617