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1.
Environ Health ; 20(1): 87, 2021 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-34340709

RESUMO

BACKGROUND: Flaws in the science supporting pesticide risk assessment and regulation stand in the way of progress in mitigating the human health impacts of pesticides. Critical problems include the scope of regulatory testing protocols, the near-total focus on pure active ingredients rather than formulated products, lack of publicly accessible information on co-formulants, excessive reliance on industry-supported studies coupled with reticence to incorporate published results in the risk assessment process, and failure to take advantage of new scientific opportunities and advances, e.g. biomonitoring and "omics" technologies. RECOMMENDED ACTIONS: Problems in pesticide risk assessment are identified and linked to study design, data, and methodological shortcomings. Steps and strategies are presented that have potential to deepen scientific knowledge of pesticide toxicity, exposures, and risks. We propose four solutions: (1) End near-sole reliance in regulatory decision-making on industry-supported studies by supporting and relying more heavily on independent science, especially for core toxicology studies. The cost of conducting core toxicology studies at labs not affiliated with or funded directly by pesticide registrants should be covered via fees paid by manufacturers to public agencies. (2) Regulators should place more weight on mechanistic data and low-dose studies within the range of contemporary exposures. (3) Regulators, public health agencies, and funders should increase the share of exposure-assessment resources that produce direct measures of concentrations in bodily fluids and tissues. Human biomonitoring is vital in order to quickly identify rising exposures among vulnerable populations including applicators, pregnant women, and children. (4) Scientific tools across disciplines can accelerate progress in risk assessments if integrated more effectively. New genetic and metabolomic markers of adverse health impacts and heritable epigenetic impacts are emerging and should be included more routinely in risk assessment to effectively prevent disease. CONCLUSIONS: Preventing adverse public health outcomes triggered or made worse by exposure to pesticides will require changes in policy and risk assessment procedures, more science free of industry influence, and innovative strategies that blend traditional methods with new tools and mechanistic insights.


Assuntos
Exposição Ambiental , Regulamentação Governamental , Praguicidas/toxicidade , Animais , Tomada de Decisões , Exposição Ambiental/efeitos adversos , Exposição Ambiental/legislação & jurisprudência , Exposição Ambiental/prevenção & controle , Humanos , Medição de Risco
2.
Environ Res ; 186: 109470, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32305678

RESUMO

BACKGROUND: The presence of pesticides in honey and related products is an increasing concern for consumers and producers, although there is lack of data on the current burden of exposure of the general human population through these products. We present a protocol for a systematic review and meta-analysis of contamination to insecticides, herbicides and fungicides of products from honeybees, and an estimation of how much the consumption of these products contributes to the ADI (Acceptable Daily Intake) of selected substances. OBJECTIVES: We aim to systematically review and meta-analyse studies on the contamination to plant protection products in honey, royal jelly, beeswax and propolis, applying the Navigation Guide and WHO-ILO systematic review methodology as an organizing framework. DATA SOURCES: We will search electronic academic databases for potentially relevant records from PubMed, TOXNET and EMBASE. We will include quantitative studies analysing the contamination from insecticides, herbicides and fungicides in honey, propolis, royal jelly and beeswax. In particular, we will evaluate the presence of the following substances and classes of pesticides: Glyphosate, Chlorpyrifos, pyrethroid and neonicotinoid pesticides, fungicides and acaricides. STUDY APPRAISAL AND SYNTHESIS METHODS: At least two authors will independently screen titles and abstracts at a first stage of review, and full texts at a second stage, of potentially eligible records against the eligibility criteria; data extraction of included studies will then be performed by at least two authors, in blind. At least two authors will assess risk of bias and the quality of evidence, using the most suited tools currently available. The data on prevalence of contaminated samples and concentration of pesticides in the products will be combined using meta-analysis: when more than three studies reporting the necessary measures to fit the models are available, meta-analysis will be performed separately by product and by exposure; otherwise, weighted descriptive analysis will be performed. We will report the results using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines (PRISMA).


Assuntos
Mel , Inseticidas , Doenças Profissionais , Exposição Ocupacional , Resíduos de Praguicidas , Animais , Abelhas , Humanos , Exposição Ocupacional/análise , Organização Mundial da Saúde
3.
Environ Health ; 18(1): 42, 2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-31064415

RESUMO

In response to the recent review by Gillezeau et al., The evidence of human exposure to glyphosate: A review, Environmental Health 1/19/19, here we report additional glyphosate biomonitoring data from a repository of urine samples collected from United States farmers in 1997-98. To determine if glyphosate exposure could be identified historically, we examined urine samples from a biorepository of specimens collected from US dairy farmers between 1997 and 98. We compared samples from farmers who self-reported glyphosate application in the 8 h prior to sample collection to samples from farm applicators who did not report using glyphosate. Of 18 applicator samples tested, 39% showed detectable levels of glyphosate (mean concentration 4.04 µg/kg; range:1.3-12) compared to 0% detections among 17 non glyphosate applicator samples (p-value < 0.01). One of the applicator samples that tested positive for glyphosate also tested positive for AMPA. Concentrations of glyphosate were consistent with levels reported in the prior occupational biomonitoring studies reviewed by Gillezeau et al.Accurately detecting both glyphosate and AMPA in this small sample of Wisconsin farmers demonstrates a) glyphosate exposures among farmers were occurring 20 years ago, which was prior to the widespread planting of genetically engineered glyphosate tolerant crops first approved in 1996; and b) liquid chromatography tandem mass spectrometry (LC-MS/MS) can be used for sensitive characterization in cryopreserved urine samples. These data offer an important historical benchmark to which urinary levels from current and future biomonitoring studies can be compared.


Assuntos
Indústria de Laticínios , Glicina/análogos & derivados , Herbicidas/urina , Exposição Ocupacional/análise , Estudos de Coortes , Monitoramento Ambiental , Glicina/urina , Humanos , Wisconsin , Glifosato
4.
Environ Health ; 18(1): 15, 2019 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-30857531

RESUMO

BACKGROUND: Glyphosate-based herbicides (GBHs) are broad-spectrum herbicides that act on the shikimate pathway in bacteria, fungi, and plants. The possible effects of GBHs on human health are the subject of an intense public debate for both its potential carcinogenic and non-carcinogenic effects, including potential effects on the endocrine system The present pilot study examine whether exposure to GBHs at the dose of glyphosate considered to be "safe" (the US Acceptable Daily Intake - ADI - of 1.75 mg/kg bw/day), starting from in utero life, affect the development and endocrine system across different life stages in Sprague Dawley (SD) rats. METHODS: Glyphosate alone and Roundup Bioflow, a commercial brand of GBHs, were administered in drinking water at 1.75 mg/kg bw/day to F0 dams starting from the gestational day (GD) 6 (in utero) up to postnatal day (PND) 120. After weaning, offspring were randomly distributed in two cohorts: 8 M + 8F/group animals belonging to the 6-week cohort were sacrificed after puberty at PND 73 ± 2; 10 M + 10F/group animals belonging to the 13-week cohort were sacrificed at adulthood at PND 125 ± 2. Effects of glyphosate or Roundup exposure were assessed on developmental landmarks and sexual characteristics of pups. RESULTS: In pups, anogenital distance (AGD) at PND 4 was statistically significantly increased both in Roundup-treated males and females and in glyphosate-treated males. Age at first estrous (FE) was significantly delayed in the Roundup-exposed group and serum testosterone concentration significantly increased in Roundup-treated female offspring from the 13-week cohort compared to control animals. A statistically significant increase in plasma TSH concentration was observed in glyphosate-treated males compared with control animals as well as a statistically significant decrease in DHT and increase in BDNF in Roundup-treated males. Hormonal status imbalances were more pronounced in Roundup-treated rats after prolonged exposure. CONCLUSIONS: The present pilot study demonstrate that GBHs exposure, from prenatal period to adulthood, induced endocrine effects and altered reproductive developmental parameters in male and female SD rats. In particular, it was associated with androgen-like effects, including a statistically significant increase of AGDs in both males and females, delay of FE and increased testosterone in female.


Assuntos
Glicina/análogos & derivados , Herbicidas/toxicidade , Canal Anal/anatomia & histologia , Canal Anal/efeitos dos fármacos , Animais , Sistema Endócrino/efeitos dos fármacos , Ciclo Estral/efeitos dos fármacos , Feminino , Genitália Feminina/anatomia & histologia , Genitália Feminina/efeitos dos fármacos , Genitália Masculina/anatomia & histologia , Genitália Masculina/efeitos dos fármacos , Glicina/toxicidade , Humanos , Masculino , Troca Materno-Fetal , Projetos Piloto , Gravidez , Ratos Sprague-Dawley , Maturidade Sexual/efeitos dos fármacos , Testosterona/sangue , Tireotropina/sangue , Testes de Toxicidade Subcrônica , Glifosato
5.
J Mammary Gland Biol Neoplasia ; 23(3): 149-163, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29956080

RESUMO

Breast development occurs through well-defined stages representing 'windows of susceptibility' to adverse environmental exposures that potentially modify breast cancer risk. Systematic characterization of morphology and transcriptome during normal breast development lays the foundation of our understanding of cancer etiology. We examined mammary glands in female Sprague Dawley rats across six developmental stages - pre-pubertal, peri-pubertal, pubertal, lactation, adult parous and adult nulliparous. We investigated histology by Hematoxylin and Eosin and Mallory's Trichrome stain, proliferative and apoptotic rate by immunohistochemistry and whole-transcriptome by microarrays. We identified differentially expressed genes between adjacent developmental stages by linear models, underlying pathways by gene ontology analysis and gene networks and hubs active across developmental stages by coexpression network analysis. Mammary gland development was associated with large-scale changes in the transcriptome; particularly from pre-pubertal to peri-pubertal period and the lactation period were characterized by distinct patterns of gene expression with unique biological functions such as immune processes during pre-pubertal development and cholesterol biosynthesis during lactation. These changes were reflective of the shift in mammary gland histology, from a rudimentary organ during early stages to a secretory organ during lactation followed by regression with age. Hub genes within mammary gene networks included metabolic genes such as Pparg during the pre-pubertal stage and tight junction-related genes claudins and occludins in lactating mammary glands. Transcriptome profile paired with histology enhanced our understanding of mammary development, which is fundamental in understanding the etiologic mechanism of breast cancer, especially pertaining to windows of susceptibility to environmental exposures that may alter breast cancer risk.


Assuntos
Glândulas Mamárias Animais/metabolismo , Glândulas Mamárias Animais/patologia , Transcriptoma/genética , Animais , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Claudinas/genética , Feminino , Perfilação da Expressão Gênica/métodos , Lactação/genética , Ocludina/genética , Ratos , Ratos Sprague-Dawley , Junções Íntimas/genética
6.
Pharmacol Res ; 132: 176-187, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29408497

RESUMO

The spice turmeric (Curcuma longa L.) has a long history of use as an anti-inflammatory agent. The active component curcumin induces a variety of diverse biological effects and forms a series of degradation and metabolic products in vivo. Our hypothesis is that the field of toxicogenomics provides tools that can be used to characterize the mode of action and toxicity of turmeric components and to predict turmeric-drug interactions. Male Sprague-Dawley rats were treated for 4 days with turmeric root containing about 3% curcumin (comparable to what people consume in the fresh or dried root) or a fraction of turmeric enriched for curcumin (∼74%) and liver tissue collected for gene expression analysis. Two doses of each agent were added to the diet, corresponding to 540 and 2700 mg/kg body weight/day of turmeric. The transcriptomic effects of turmeric on rat liver tissue were examined using 3 programs, ToxFx Analysis Suite, in the context of a large drug database, Ingenuity Pathway and NextBio analyses. ToxFx analysis indicates that turmeric containing about 3% or 74% curcumin represses the expression of cholesterol biosynthetic genes. The dose of 400 mg/kg b.w./day curcumin induced the Drug Signature associated with hepatic inflammatory infiltrate. Ingenuity analysis confirmed that all 4 turmeric treatments had a significant effect on cholesterol biosynthesis, specifically the Cholesterol biosynthesis superpathway and Cholesterol biosynthesis 1 and 2. Among the top 10 up or downregulated genes, all 4 treatments downregulated PDK4; while 3 treatments downregulated ANGPTL4 or FASN. These findings suggest curcumin may enhance the anticancer effects of certain classes of statins, which we confirmed with biological assays. Given this enhancement, lower levels of statins may be required, and even be desirable. Our findings also warn of possible safety issues, such as potential inflammatory liver effects, for patients who ingest a combination of certain classes of statins and curcumin. Transcriptomic analysis suggests that turmeric is worthwhile to study to prevent and treat cancer and lipid disorders. Our approach lays new groundwork for studies of the mode of action and safety of herbal medicines and can also be used to develop a methodology to standardize herbal medicines.


Assuntos
Anticolesterolemiantes/farmacologia , Colesterol/metabolismo , Curcuma , Curcumina/farmacologia , Preparações de Plantas/farmacologia , Sinvastatina/farmacologia , Transcriptoma/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Sinergismo Farmacológico , Perfilação da Expressão Gênica , Humanos , Masculino , Raízes de Plantas , Ratos Sprague-Dawley
7.
Environ Health ; 17(1): 51, 2018 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-29843729

RESUMO

BACKGROUND: Glyphosate, formulated as Roundup, is the world's most widely used herbicide. Glyphosate is used extensively on genetically modified (GM) food crops designed to tolerate the herbicide, and global use is increasing rapidly. Two recent reviews of glyphosate's health hazards report conflicting results. An independent review by the International Agency for Research on Cancer (IARC) found that glyphosate is a "probable human carcinogen". A review by the European Food Safety Agency (EFSA) found no evidence of carcinogenic hazard. These differing findings have produced regulatory uncertainty. REGULATORY ACTIONS: Reflecting this regulatory uncertainty, the European Commission on November 27 2017, extended authorization for glyphosate for another 5 years, while the European Parliament opposed this decision and issued a call that pesticide approvals be based on peer-reviewed studies by independent scientists rather than on the current system that relies on proprietary industry studies. RAMAZZINI INSTITUTE RESPONSE: The Ramazzini Institute has initiated a pilot study of glyphosate's health hazards that will be followed by an integrated experimental research project. This evaluation will be independent of industry support and entirely sponsored by worldwide crowdfunding. The aim of the Ramazzini Institute project is to explore comprehensively the effects of exposures to glyphosate-based herbicides at current real-world levels on several toxicological endpoints, including carcinogenicity, long-term toxicity, neurotoxicity, endocrine disrupting effects, prenatal developmental toxicity, the microbiome and multi-generational effects.


Assuntos
Glicina/análogos & derivados , Herbicidas/efeitos adversos , Medição de Risco , Glicina/efeitos adversos , Humanos , Pesquisa , Glifosato
8.
Environ Health ; 17(1): 50, 2018 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-29843725

RESUMO

BACKGROUND: Glyphosate-based herbicides (GBHs) are broad-spectrum herbicides that act on the shikimate pathway in bacteria, fungi, and plants. The possible effects of GBHs on human health are the subject of an intense public debate for both its potential carcinogenic and non-carcinogenic effects, including its effects on microbiome. The present pilot study examines whether exposure to GBHs at doses of glyphosate considered to be "safe" (the US Acceptable Daily Intake - ADI - of 1.75 mg/kg bw/day), starting from in utero, may modify the composition of gut microbiome in Sprague Dawley (SD) rats. METHODS: Glyphosate alone and Roundup, a commercial brand of GBHs, were administered in drinking water at doses comparable to the US glyphosate ADI (1.75 mg/kg bw/day) to F0 dams starting from the gestational day (GD) 6 up to postnatal day (PND) 125. Animal feces were collected at multiple time points from both F0 dams and F1 pups. The gut microbiota of 433 fecal samples were profiled at V3-V4 region of 16S ribosomal RNA gene and further taxonomically assigned and assessed for diversity analysis. We tested the effect of exposure on overall microbiome diversity using PERMANOVA and on individual taxa by LEfSe analysis. RESULTS: Microbiome profiling revealed that low-dose exposure to Roundup and glyphosate resulted in significant and distinctive changes in overall bacterial composition in F1 pups only. Specifically, at PND31, corresponding to pre-pubertal age in humans, relative abundance for Bacteriodetes (Prevotella) was increased while the Firmicutes (Lactobacillus) was reduced in both Roundup and glyphosate exposed F1 pups compared to controls. CONCLUSIONS: This study provides initial evidence that exposures to commonly used GBHs, at doses considered safe, are capable of modifying the gut microbiota in early development, particularly before the onset of puberty. These findings warrant future studies on potential health effects of GBHs in early development such as childhood.


Assuntos
Microbioma Gastrointestinal/efeitos dos fármacos , Glicina/análogos & derivados , Herbicidas/efeitos adversos , Animais , Bactérias/classificação , Bactérias/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Glicina/efeitos adversos , Masculino , Projetos Piloto , Ratos , Ratos Sprague-Dawley , Glifosato
9.
Environ Health ; 17(1): 52, 2018 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-29843719

RESUMO

BACKGROUND: Glyphosate-based herbicides (GBHs) are the most widely used pesticides worldwide, and glyphosate is the active ingredient of such herbicides, including the formulation known as Roundup. The massive and increasing use of GBHs results in not only the global burden of occupational exposures, but also increased exposure to the general population. The current pilot study represents the first phase of a long-term investigation of GBHs that we are conducting over the next 5 years. In this paper, we present the study design, the first evaluation of in vivo parameters and the determination of glyphosate and its major metabolite aminomethylphosphonic acid (AMPA) in urine. METHODS: We exposed Sprague-Dawley (SD) rats orally via drinking water to a dose of glyphosate equivalent to the United States Acceptable Daily Intake (US ADI) of 1.75 mg/kg bw/day, defined as the chronic Reference Dose (cRfD) determined by the US EPA, starting from prenatal life, i.e. gestational day (GD) 6 of their mothers. One cohort was continuously dosed until sexual maturity (6-week cohort) and another cohort was continuously dosed until adulthood (13-week cohort). Here we present data on general toxicity and urinary concentrations of glyphosate and its major metabolite AMPA. RESULTS: Survival, body weight, food and water consumption of the animals were not affected by the treatment with either glyphosate or Roundup. The concentration of both glyphosate and AMPA detected in the urine of SD rats treated with glyphosate were comparable to that observed in animals treated with Roundup, with an increase in relation to the duration of treatment. The majority of glyphosate was excreted unchanged. Urinary levels of the parent compound, glyphosate, were around 100-fold higher than the level of its metabolite, AMPA. CONCLUSIONS: Glyphosate concentrations in urine showed that most part of the administered dose was excreted as unchanged parent compound upon glyphosate and Roundup exposure, with an increasing pattern of glyphosate excreted in urine in relation to the duration of treatment. The adjuvants and the other substances present in Roundup did not seem to exert a major effect on the absorption and excretion of glyphosate. Our results demonstrate that urinary glyphosate is a more relevant marker of exposure than AMPA in the rodent model.


Assuntos
Glicina/análogos & derivados , Herbicidas/toxicidade , Herbicidas/urina , Animais , Relação Dose-Resposta a Droga , Glicina/toxicidade , Glicina/urina , Humanos , Projetos Piloto , Ratos , Ratos Sprague-Dawley , Projetos de Pesquisa , Glifosato
10.
Environ Res ; 152: 233-243, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27810681

RESUMO

Exposure to environmental chemicals has been linked to altered mammary development and cancer risk at high doses using animal models. Effects at low doses comparable to human exposure remain poorly understood, especially during critical developmental windows. We investigated the effects of two environmental phenols commonly used in personal care products - methyl paraben (MPB) and triclosan (TCS) - on the histology and transcriptome of normal mammary glands at low doses mimicking human exposure during critical windows of development. Sprague-Dawley rats were exposed during perinatal, prepubertal and pubertal windows, as well as from birth to lactation. Low-dose exposure to MPB and TCS induced measurable changes in both mammary histology (by Masson's Trichrome Stain) and transcriptome (by microarrays) in a window-specific fashion. Puberty represented a window of heightened sensitivity to MPB, with increased glandular tissue and changes of expression in 295 genes with significant enrichment in functions such as DNA replication and cell cycle regulation. Long-term exposure to TCS from birth to lactation was associated with increased adipose and reduced glandular and secretory tissue, with expression alterations in 993 genes enriched in pathways such as cholesterol synthesis and adipogenesis. Finally, enrichment analyses revealed that genes modified by MPB and TCS were over-represented in human breast cancer gene signatures, suggesting possible links with breast carcinogenesis. These findings highlight the issues of critical windows of susceptibility that may confer heightened sensitivity to environmental insults and implicate the potential health effects of these ubiquitous environmental chemicals in breast cancer.


Assuntos
Poluentes Ambientais/toxicidade , Glândulas Mamárias Animais/efeitos dos fármacos , Parabenos/toxicidade , Triclosan/toxicidade , Animais , Anti-Infecciosos Locais/toxicidade , Relação Dose-Resposta a Droga , Feminino , Perfilação da Expressão Gênica , Glândulas Mamárias Animais/anatomia & histologia , Glândulas Mamárias Animais/crescimento & desenvolvimento , Conservantes Farmacêuticos/toxicidade , Ratos , Ratos Sprague-Dawley , Maturidade Sexual/efeitos dos fármacos , Transcriptoma/efeitos dos fármacos
12.
Environ Health ; 15(1): 97, 2016 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-27729050

RESUMO

Aneuploidy, defined as structural and numerical aberrations of chromosomes, continues to draw attention as an informative effect biomarker for carcinogens and male reproductive toxicants. It has been well documented that aneuploidy is a hallmark of cancer. Aneuploidies in oocytes and spermatozoa contribute to infertility, pregnancy loss and a number of congenital abnormalities, and sperm aneuploidy is associated with testicular cancer. It is striking that several carcinogens induce aneuploidy in somatic cells, and also adversely affect the chromosome compliment of germ cells. In this paper we review 1) the contributions of aneuploidy to cancer, infertility, and developmental abnormalities; 2) techniques for assessing aneuploidy in precancerous and malignant lesions and in sperm; and 3) the utility of aneuploidy as a biomarker for integrated chemical assessments of carcinogenicity, and reproductive and developmental toxicity.


Assuntos
Aneuploidia , Animais , Biomarcadores , Carcinógenos/toxicidade , Humanos , Masculino , Neoplasias/genética , Reprodução , Espermatozoides/fisiologia
13.
Am J Ind Med ; 59(7): 509-21, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27219869

RESUMO

BACKGROUND: Experimental rodent bioassays performed up to now have failed to provide conclusive confirmation of the carcinogenicity of extremely low frequency magnetic fields (ELFMF). OBJECTIVES: To evaluate the potential synergistic carcinogenic effects of concurrent exposure to ELFMF and formaldehyde in four groups of male and female Sprague-Dawley rats. METHODS: One group was exposed from prenatal life until natural death to S-50 Hz MF and to formaldehyde in drinking water from 6 weeks of age for 104 weeks, two groups were treated only with formaldehyde or only with MF and one group served as untreated control. RESULTS: Compared to untreated controls, exposure to MF and formaldehyde causes in males a statistically significant increased incidence of malignant tumors (P ≤ 0.01), thyroid C-cell carcinomas (P ≤ 0.01), and hemolymphoreticular neoplasias (P ≤ 0.05). No statistically significant differences were observed among female groups. CONCLUSIONS: Life-span exposure to MF and formaldehyde induces statistically significant carcinogenic effects in male rats. Am. J. Ind. Med. 59:509-521, 2016. © 2016 Wiley Periodicals, Inc.


Assuntos
Cocarcinogênese , Formaldeído/efeitos adversos , Neoplasias Hematológicas/etiologia , Campos Magnéticos/efeitos adversos , Neoplasias da Glândula Tireoide/etiologia , Animais , Carcinógenos , Feminino , Estimativa de Kaplan-Meier , Leucemia/etiologia , Linfoma/etiologia , Masculino , Ratos , Ratos Sprague-Dawley , Fatores Sexuais , Neoplasias da Glândula Tireoide/patologia
14.
Am J Ind Med ; 58(1): 46-60, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25351660

RESUMO

BACKGROUND: Experimental long-term carcinogenicity bioassays conducted on rats and mice proved that ionizing radiation can induce a variety of tumor types. However few studies have been conducted on rats. METHODS: This report deals with the effects of γ-radiation in groups of 416-1,051 6-weeks old Sprague-Dawley rats exposed to 0, 0.1, 1, or 3 Gy of γ-radiation delivered in a single acute exposure. The experiment lasted for the animals' lifespan and all were necropsied and underwent full histopathological evaluation. RESULTS: The results confirm the dose-related carcinogenic effects of γ-radiation for several organs and tissues. Moreover they indicate that exposure to 0.1 Gy induces a statistically significant increased incidence in Zymbal gland carcinomas and pancreas islet cell carcinomas in females. CONCLUSIONS: Our data show that exposure to γ-radiation induces carcinogenic effects at all tested doses.


Assuntos
Raios gama/efeitos adversos , Neoplasias/epidemiologia , Neoplasias/etiologia , Animais , Autopsia , Testes de Carcinogenicidade , Modelos Animais de Doenças , Relação Dose-Resposta à Radiação , Feminino , Masculino , Neoplasias/classificação , Modelos de Riscos Proporcionais , Doses de Radiação , Ratos , Ratos Sprague-Dawley , Projetos de Pesquisa
15.
Am J Ind Med ; 57(4): 383-97, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24436139

RESUMO

Aspartame (APM) is an artificial sweetener used since the 1980s, now present in >6,000 products, including over 500 pharmaceuticals. Since its discovery in 1965, and its first approval by the US Food and Drugs Administration (FDA) in 1981, the safety of APM, and in particular its carcinogenicity potential, has been controversial. The present commentary reviews the adequacy of the design and conduct of carcinogenicity bioassays on rodents submitted by G.D. Searle, in the 1970s, to the FDA for market approval. We also review how experimental and epidemiological data on the carcinogenic risks of APM, that became available in 2005 motivated the European Commission (EC) to call the European Food and Safety Authority (EFSA) for urgent re-examination of the available scientific documentation (including the Searle studies). The EC has further requested that, if the results of the evaluation should suggest carcinogenicity, major changes must be made to the current APM specific regulations. Taken together, the studies performed by G.D. Searle in the 1970s and other chronic bioassays do not provide adequate scientific support for APM safety. In contrast, recent results of life-span carcinogenicity bioassays on rats and mice published in peer-reviewed journals, and a prospective epidemiological study, provide consistent evidence of APM's carcinogenic potential. On the basis of the evidence of the potential carcinogenic effects of APM herein reported, a re-evaluation of the current position of international regulatory agencies must be considered an urgent matter of public health.


Assuntos
Aspartame/toxicidade , Carcinógenos/toxicidade , Qualidade de Produtos para o Consumidor/normas , Neoplasias/induzido quimicamente , Adoçantes não Calóricos/toxicidade , Animais , Testes de Carcinogenicidade/normas , Europa (Continente) , Humanos , Estados Unidos , United States Food and Drug Administration
16.
PLoS One ; 19(1): e0296699, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38232086

RESUMO

The cancer hazard associated with lifetime exposure to radiofrequency radiation (RFR) was examined in Sprague Dawley (SD) rats at the Ramazzini Institute (RI), Italy. There were increased incidences of gliomas and cardiac schwannomas. The translational relevance of these rare rat tumors for human disease is poorly understood. We examined the genetic alterations in RFR-derived rat tumors through molecular characterization of important cancer genes relevant for human gliomagenesis. A targeted next-generation sequencing (NGS) panel was designed for rats based on the top 23 orthologous human glioma-related genes. Single-nucleotide variants (SNVs) and small insertion and deletions (indels) were characterized in the rat gliomas and cardiac schwannomas. Translational relevance of these genetic alterations in rat tumors to human disease was determined through comparison with the Catalogue of Somatic Mutations in Cancer (COSMIC) database. These data suggest that rat gliomas resulting from life-time exposure to RFR histologically resemble low grade human gliomas but surprisingly no mutations were detected in rat gliomas that had homology to the human IDH1 p.R132 or IDH2 p.R172 suggesting that rat gliomas are primarily wild-type for IDH hotspot mutations implicated in human gliomas. The rat gliomas appear to share some genetic alterations with IDH1 wildtype human gliomas and rat cardiac schwannomas also harbor mutations in some of the queried cancer genes. These data demonstrate that targeted NGS panels based on tumor specific orthologous human cancer driver genes are an important tool to examine the translational relevance of rodent tumors resulting from chronic/life-time rodent bioassays.


Assuntos
Neoplasias Encefálicas , Glioma , Neurilemoma , Exposição à Radiação , Humanos , Ratos , Animais , Ratos Sprague-Dawley , Glioma/genética , Glioma/patologia , Mutação , Neurilemoma/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Isocitrato Desidrogenase/genética , Neoplasias Encefálicas/patologia
19.
Arch Ital Urol Androl ; 84(4): 189-96, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23427742

RESUMO

Many studies have drawn attention to the possible association between occupational exposure to asbestos and tumours of the urinary apparatus. Besides the main etiological agents recognised today--such as smoking, obesity and hypertension--experimental and epidemiological evidence converges on the view that tumours of the kidney and bladder are largely due to occupational exposure to industrial agents: these and their transformation products linger in the body and are eventually eliminated by those organs. That one such agent targeting the urinary system is asbestos has found confirmation in the discovery of asbestos fibres in the urine of populations at risk. We here present 23 cases of work exposure to asbestos in a range of exposure scenarios where the workers developed tumours of the kidney and bladder. The cases came to the attention of the Ramazzini Institute casually.


Assuntos
Amianto/efeitos adversos , Exposição Ocupacional/efeitos adversos , Neoplasias Urológicas/etiologia , Academias e Institutos , Humanos , Itália , Neoplasias Urológicas/epidemiologia
20.
Toxins (Basel) ; 14(5)2022 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-35622572

RESUMO

The term toxicant-associated fatty liver disease (TAFLD) has been proposed to describe fatty liver diseases connected to toxicants other than alcohol. Aflatoxins are mycotoxins commonly found as contaminants in foods and feeds, which are known liver toxicants and potential candidates as potential causes of TAFLD. Aflatoxin B1 (AFB1) was administered at low doses to Sprague-Dawley (SD) rats, alone or in combination with S-50 Hz an extremely low frequency electromagnetic field (ELFEMF), to study the evolution of TAFLD, preneoplastic and neoplastic lesions of the liver and the potential enhancing effect of lifespan exposure to ELFEMF. Steatosis, inflammation and foci of different types were significantly increased in both aflatoxin-treated males and females, which is consistent with a pattern of TAFLD. A significant increase in adenomas, cystic dilation of biliary ducts, hepatocellular hyperplasia and hypertrophy and oval cell hyperplasia were also observed in treated females only. The administration of low doses of AFB1 caused TAFLD in SD rats, inducing liver lesions encompassing fatty infiltration, foci of different types and adenomas. Furthermore, the pattern of change observed in preneoplastic liver lesions often included liver steatosis and steatohepatitis (TASH). ELFEMF did not result in any enhancing or toxic effect in the liver of SD rats.


Assuntos
Aflatoxinas , Fígado Gorduroso , Neoplasias Hepáticas , Aflatoxina B1/metabolismo , Aflatoxina B1/toxicidade , Animais , Campos Eletromagnéticos , Feminino , Hiperplasia , Masculino , Ratos , Ratos Sprague-Dawley
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