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1.
Toxicol Rep ; 8: 1856-1864, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34820291

RESUMO

Mycotoxins are secondary fungi metabolites that induce acute and chronic toxic effects in humans and animals. In the present study, nine mycotoxins including aflatoxins (AFB1, AFB2, AFG1 and AFG2), fumonisins (FB1 and FB2), Ochratoxin A (OTA), deoxynivalenol (DON), and zearalenone (ZEN) were determined in one hundred rice samples collected from Tehran using high performance liquid chromatography (HPLC) with fluorescence or photodiode array detector. In addition, possible risk to public health was investigated by assessing dietary exposure through rice consumption, the margin of exposure (MOE), respective risk of cancer and hazard index (HI) of the monitored mycotoxins in children and adults. The higher mean levels were determined for DON (102.22 µg.Kg-1), followed by FB1 (85.00 µg.Kg-1). For the rests of mycotoxins the levels did not exceed 20 µg.Kg-1. The estimated AFB1 intake for the adults and children through rice consumption exceeds the safe levels established for both carriers and non-carriers of hepatitis B virus. The mean and median determined exposure levels of OTA, DON ZEN and FB1, were found lower than the Provisional Maximum Tolerable Daily Intake (PMTDI) value for both adults and children of Tehran that consuming domestic and imported rice. The mean HI for adults and median HI for adults and children were below one, and mean HI for children was close to one. All the mean, median and maximum MoE values were <10,000 in adults and children, indicating a risk due to AFB1 exposure through rice consumption in Tehran. In addition, the calculated mean cancer risk in adult and child populations of Tehran were 0.27 and 0.64 cases per year per 105 individuals, respectively, that shows population in Tehran could be at risk of cancer due to AFB1 exposure through rice consumption as calculated. So further studies are necessary for the monitoring mycotoxins in rice and different food products as well as estimating average dietary exposure and cumulative exposure assessment of mycotoxins for main foods in IR Iran.

2.
Food Chem Toxicol ; 152: 112188, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33836210

RESUMO

This study aimed to evaluate the long-term low-dose effects of exposure to a mixture of 6 pesticide active substances (diquat, imazamox, imazethapyr, tepraloxydin, bentazone, acifluorfen) and to elucidate if chronic vitamin deficiency can influence their toxicity. Two hundred Wistar rats were divided in 4 groups: a vitamin-sufficiency control group, a vitamin-deficiency control group, a vitamin sufficiency test group and a vitamin-deficiency test group. The test groups were treated with the aforementioned pesticides at doses 100 times lower than the corresponding NOAEL. After 6 months, ten rats from each group were sacrificed and a complete evaluation of blood and urine biochemistry, biomarkers of oxidative stress, xenobiotic detoxification enzymes and lysosomal enzymes and organ histopathology was performed. The pesticides mixture and vitamin deficiency determined an increase in alkaline phosphatase levels and urinary calcium levels, abnormal serum lipid profile, and a decrease of total blood proteins levels, red blood cells, haematocrit and haemoglobin. The combination of the two stressors up-regulated CYP1A1, CYP1A2, CYP2B1 and GST levels. This study provides a new proof for the need to move forward from single chemical testing to a more complex approach to account for the multitude of stressors that can challenge the setting of real safety levels.


Assuntos
Deficiência de Vitaminas/fisiopatologia , Praguicidas/toxicidade , Fosfatase Alcalina/sangue , Fosfatase Alcalina/metabolismo , Animais , Deficiência de Vitaminas/sangue , Peso Corporal/efeitos dos fármacos , Peso Corporal/fisiologia , Cálcio/metabolismo , Cálcio/urina , Colesterol/sangue , Colesterol/metabolismo , Doença Crônica , Lipase/sangue , Lipase/metabolismo , Masculino , Tamanho do Órgão/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Ratos Wistar , Fatores de Tempo , Triglicerídeos/sangue , Triglicerídeos/metabolismo
3.
Food Chem Toxicol ; 146: 111844, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33152470

RESUMO

Cattle milk's health benefits can be compromised by the presence of contaminants. The levels of cadmium, copper, lead and zinc, and residues of dichlorodiphenyldichloroethylene (DDE), dichlorodiphenyldichloroethane (DDD), dichlorodiphenyltrichloroethane (DDT) were determined in soil, milk and cheese samples collected from cow farms from 3 Romanian areas with industrial and agriculture tradition. A new methodology was applied for the determination of the corrected estimated daily intake (cEDI) corresponding to the aggregate dietary exposure. For the risk assessment, we calculated the source hazard quotient (HQs) for each contaminant and the adversity specific hazard index (HIA). Cadmium, copper, lead and zinc, and the sum of DDT levels in soil samples were below maximum residue levels (MRLs). The MRLs of lead and DDD were exceeded in milk and cheese samples from all the 3 areas. The MRLs of copper and zinc were exceeded in cheese samples from area 2 and 3. HQs >10 for lead indicates increased risk, while HQ > 1 for copper and sum of DDT indicates moderate risk for both milk and cheese. By calculating the HIA, we identified a moderate and increase risk for nephrotoxicity, hepatotoxicity, hematotoxicity, cardiotoxicity and reproduction toxicity after consumption of the dairy products from the 3 areas.


Assuntos
Queijo/análise , Contaminação de Alimentos , Metais Pesados/química , Leite/química , Resíduos de Praguicidas/química , Praguicidas/toxicidade , Animais , Humanos , Poluentes do Solo/química
4.
Toxics ; 8(3)2020 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-32867022

RESUMO

Recent research has helped clarify the role of cadmium (Cd) in various pathological states. We have demonstrated Cd involvement in pancreatic cancer, as well as the bioaccumulation of Cd in the pancreas. Bioaccumulation and increased toxicity suggest that Cd may also be involved in other pancreas-mediated diseases, like diabetes. Cd falls into the category of "hyperglycemic" metals, i.e., metals that increase blood glucose levels, which could be due to increased gluconeogenesis, damage to ß-cells leading to reduced insulin production, or insulin resistance at target tissue resulting in a lack of glucose uptake. This review addresses the current evidence for the role of Cd, leading to insulin resistance from human, animal, and in vitro studies. Available data have shown that Cd may affect normal insulin function through multiple pathways. There is evidence that Cd exposure results in the perturbation of the enzymes and modulatory proteins involved in insulin signal transduction at the target tissue and mutations of the insulin receptor. Cd, through well-described mechanisms of oxidative stress, inflammation, and mitochondrial damage, may also alter insulin production in ß-cells. More work is necessary to elucidate the mechanisms associated with Cd-mediated insulin resistance.

5.
Toxicol Rep ; 7: 1090-1094, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32953461

RESUMO

Genotoxicity of the mixture of generic pesticides imidacloprid + imazalil + tebuconazole in a ratio of 14.0/1.7/1.0 by weight was assessed using Ames test (Salmonella typhimurium) and micronucleus test in vivo on mammalian bone marrow erythrocytes (CD-1 mice) supporting the data creation for the Real Life Risk Simulation (RLRS) approach. This pesticides' combination is used in the commercial formulation for seed treatment in advance of or immediately before sowing. Tested pesticides' technical grade active ingredients (TGAIs) showed no evidence of genotoxicity upon separate treatments. In combination, the three pesticides demonstrated negative results in the Ames test but induced a statistically significant, dose-depended increase in MN-PCEs in mice bone marrow at doses lower than those used separately. The observed effect may be mediated by the synergistic action of the tested TGAIs, their metabolites or impurities.

6.
Toxicol Rep ; 7: 1057-1065, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32923372

RESUMO

Greek fermentation and distillation industries produce traditional spirit beverages, such as tsipouro and tsikoudia, consumed both in bottles and bulk quantities by the general population or tourists. The same spirits are also produced by individuals at home since previous centuries, as a part of the local culture but mainly due to the Greek agricultural sector unique characteristics (small cultivation areas with great number of farmers). In this study, the concentrations of carcinogenic compounds: ethanol and acetaldehyde; and noncarcinogenic: higher alcohols (1-propanol, isobutanol, and isoamyl alcohol), esters (ethyl acetate), and methanol were measured to estimate the potential cancer risk and daily intake of these compounds. The margin of exposure (MOE) of carcinogenic compounds was found to be less than 500 (mean value), well below the toxic threshold of 10,000, above which there is not public concern, as suggested by the European Food Safety Authority. Additionally, through risk assessment of noncarcinogenic compounds, we identified two specific compounds in-bulk spirits (produced by individuals), namely ethyl acetate and isobutanol, with health risk index (HRI) greater than 1 (indicating a possibility to induce side effects by consumption of high amounts). Our results indicate that bottled spirits, which are produced in a controlled environment (alcohol industries), showed higher human safety level in terms of both carcinogenic and noncarcinogenic risk assessment studies, comparing to bulk beverages produced by individuals (with out strict regulations).

7.
Food Chem Toxicol ; 142: 111455, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32474022

RESUMO

In this study, two accurate, precise, selective and sensitive methods were developed for determining aflatoxin M1 (AFM1) in infant formula milk using immunoaffinity column clean-up followed by high performance liquid chromatography (HPLC) with fluorescence detection. The validated methods were used for determination of AFM1 in 29 samples of 6 different infant formula milk brands and the risk of AFM1 in infants aged zero to 6 months old was assessed using cancer risk, Margin of Exposure (MOE) and Hazard Index (HI). Only one sample (3.4%) was contaminated with AFM1. Although the results showed that MOE values for the mean and median exposure to AFM1 was <10,000 in infants, the additional cancer risk due to mean and median exposure to AFM1 in infant <6 months were 0.00010 and 0.00012 additional cases per year per 105 individuals, respectively, which indicates no health concern. In addition, HI values for the mean and median exposure to AFM1 for infants were quite below one which indicates no health concern. To the best of our knowledge, this is the first report on risk assessment of AFM1 in infant formula milk consumed by Iranian infants <6 months old, presenting a low risk for the evaluated groups.


Assuntos
Aflatoxina M1/toxicidade , Exposição Dietética , Contaminação de Alimentos/análise , Fórmulas Infantis/análise , Aflatoxina M1/análise , Humanos , Lactente , Recém-Nascido , Irã (Geográfico) , Medição de Risco
8.
Food Chem Toxicol ; 141: 111418, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32437891

RESUMO

Occupational, residential, dietary and environmental exposures to mixtures of synthetic anthropogenic chemicals after World War II have a strong relationship with the increase of chronic diseases, health cost and environmental pollution. The link between environment and immunity is particularly intriguing as it is known that chemicals and drugs can cause immunotoxicity (e.g., allergies and autoimmune diseases). In this review, we emphasize the relationship between long-term exposure to xenobiotic mixtures and immune deficiency inherent to chronic diseases and epidemics/pandemics. We also address the immunotoxicologic risk of vulnerable groups, taking into account biochemical and biophysical properties of SARS-CoV-2 and its immunopathological implications. We particularly underline the common mechanisms by which xenobiotics and SARS-CoV-2 act at the cellular and molecular level. We discuss how long-term exposure to thousand chemicals in mixtures, mostly fossil fuel derivatives, exposure toparticle matters, metals, ultraviolet (UV)-B radiation, ionizing radiation and lifestyle contribute to immunodeficiency observed in the contemporary pandemic, such as COVID-19, and thus threaten global public health, human prosperity and achievements, and global economy. Finally, we propose metrics which are needed to address the diverse health effects of anthropogenic COVID-19 crisis at present and those required to prevent similar future pandemics.


Assuntos
Poluentes Atmosféricos/toxicidade , Betacoronavirus , Infecções por Coronavirus/epidemiologia , Praguicidas/toxicidade , Pneumonia Viral/epidemiologia , Xenobióticos/toxicidade , Animais , Antivirais/uso terapêutico , COVID-19 , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/fisiopatologia , Dieta , Epidemias , Humanos , Sistema Imunitário/efeitos dos fármacos , Pandemias , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/fisiopatologia , Prevalência , Receptores de Hidrocarboneto Arílico/metabolismo , Fatores de Risco , SARS-CoV-2 , Transdução de Sinais/efeitos dos fármacos , Tempo
9.
Mol Med Rep ; 22(1): 20-32, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32319647

RESUMO

Italy is currently one of the countries seriously affected by the COVID­19 pandemic. As per 10 April 2020, 147,577 people were found positive in a total of 906,864 tests performed and 18,849 people lost their lives. Among all cases, 70.2% of positive, and 79.4% of deaths occurred in the provinces of Northern Italy (Lombardi, Emilia Romagna, Veneto and Piemonte), where the outbreak first started. Originally, it was considered that the high number of positive cases and deaths in Italy resulted from COVID­19 initially coming to Italy from China, its presumed country of origin. However, an analysis of the factors that played a role in the extent of this outbreak is needed. Evaluating which factors could be specific for a country and which might contribute the most is nevertheless complex, with accompanying high uncertainty. The purpose of this work is to discuss some of the possible contributing factors and their possible role in the relatively high infection and death rates in Northern Italy compared to other areas and countries.


Assuntos
COVID-19/epidemiologia , Surtos de Doenças , Humanos , Itália/epidemiologia , Pandemias , Fatores de Risco , SARS-CoV-2/isolamento & purificação
10.
Mol Med Rep ; 21(6): 2293-2295, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32236594

RESUMO

Covid­19 origin and transmission to humans. Covid­19 infection began in Wuhan (Hubei, China) in December, 2019. Although to date it is considered that Covid­19 originates from bats (96.2% overall genome sequence identity) (1), the type of intermediate animals that caused the transmission to humans remains unknown (2-4). Zhou et al (1) mentioned that 'Direct contact with intermediate host animals or consumption of wild animals was suspected to be the main route of SARS­CoV­2 transmission. However, the source(s) and transmission routine(s) of SARS­CoV­2 remain elusive' (1).


Assuntos
COVID-19/transmissão , COVID-19/veterinária , Surtos de Doenças , Doenças do Cão/transmissão , Animais , COVID-19/epidemiologia , Surtos de Doenças/veterinária , Doenças do Cão/virologia , Cães , Humanos , Itália/epidemiologia , SARS-CoV-2/genética , SARS-CoV-2/isolamento & purificação
11.
Int J Mol Med ; 45(6): 1631-1643, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32236624

RESUMO

The new outbreak of coronavirus from December 2019 has brought attention to an old viral enemy and has raised concerns as to the ability of current protection measures and the healthcare system to handle such a threat. It has been known since the 1960s that coronaviruses can cause respiratory infections in humans; however, their epidemic potential was understood only during the past two decades. In the present review, we address current knowledge on coronaviruses from a short history to epidemiology, pathogenesis, clinical manifestation of the disease, as well as treatment and prevention strategies. Although a great amount of research and efforts have been made worldwide to prevent further outbreaks of coronavirus­associated disease, the spread and lethality of the 2019 outbreak (COVID­19) is proving to be higher than previous epidemics on account of international travel density and immune naivety of the population. Only strong, joint and coordinated efforts of worldwide healthcare systems, researchers, and pharmaceutical companies and receptive national leaders will succeed in suppressing an outbreak of this scale.


Assuntos
Betacoronavirus/patogenicidade , Infecções por Coronavirus/virologia , Coronavirus/patogenicidade , Surtos de Doenças , Pneumonia Viral/virologia , Betacoronavirus/fisiologia , COVID-19 , Coronavirus/fisiologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/terapia , Humanos , Pandemias/prevenção & controle , Pneumonia Viral/epidemiologia , Pneumonia Viral/prevenção & controle , Pneumonia Viral/terapia , SARS-CoV-2
12.
Food Chem Toxicol ; 140: 111346, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32334109

RESUMO

Toxic stimuli (stressors) exposure limits are typically based on single toxic stimuli experiments, but are presently used for both toxic stimuli in isolation and in combination with other toxic stimuli (simultaneous co-exposure or exposures separated in time). In the combination case, typically less of each constituent of the combination is required to cause damage compared to the amount determined from single stressor experiments. Thus, exposure limits based on single toxic stimulus experiments are inadequate for setting limits for stressor combinations. This article presents a recommended simplified approach to improving regulatory exposure limits for toxic stimuli combinations, and a more expansive and expensive alternative to the recommended simplified approach. The recommended approach will partially compensate for the enhanced adverse effects of toxic stimuli combinations relative to adverse effects of toxic stimuli in isolation. The approach covers myriad categories of toxic stimuli reflective of real-life exposures due to lifestyle, iatrogenic, biotoxin, occupational/environmental, and psychosocial/socioeconomic conditions. The proposed approach 1) assumes that all potential toxic stimuli to which an individual might be exposed have the same mechanisms/modes of action on biological mechanisms, and are, thus, indistinguishable by the impacted organism; 2) normalizes the myriad stimuli by converting the doses of toxic stimuli exposures to the respective toxicity reference values (TRV) fractions; 3) sums all the TRVs fractions from these toxic stimuli exposures; and 4) divides all the single substance TRVs by the sum of fractions. While it is an additive approach conceptually, it differs from other additive approaches in the breadth of its inter-category coverage, in order to reflect true inter-category real-life simulation. The newly posited approach does not account for hormetic, antagonistic, or synergistic effects of toxic stimuli in combination. It does not adjust for 1) low-dose toxicants with adverse effects that have been under-reported, or 2) exposure limits like the Occupational Safety and Health Administration - Permissible Exposure Limits (OSHA PELs) that are orders of magnitude above levels shown by published single toxic stimuli studies to have caused adverse effects. Practical considerations for the application of this approach are presented.


Assuntos
Exposição Ambiental , Substâncias Perigosas/toxicidade , Humanos
13.
Food Chem Toxicol ; 140: 111262, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32198030

RESUMO

Pesticides are widely used in agriculture and their proven high toxicity makes the need of monitoring their presence in food imperative. A multi residue method is applied in apples samples (81) collected from the Greek market for the monitoring of 40 analytes. Pesticides levels were evaluated by gas and liquid chromatography-mass spectrometry using a QuEChERs protocol. Risk for consumers was assessed by a newly developed methodology, employing the source related Hazard Quotient (HQs) and the adversity specific Hazard Index (HIA). The 84% of the apple's samples were positive for at least one pesticide, 21% for one pesticide, 55.6% for two to four pesticide residues and 7.4% for more than 4 pesticide residues. The most frequently detected compound was carbendazim (45.7%) followed by chlorpyrifos (44.4.0%). The mean detected concentration levels varied from 0.169 ppm (fluopyram) to 0.005 ppm (triazophos). 19 of the 40 investigated pesticides were not detected in any apple sample. For all individual pesticides, the source related Hazard Quotient (HQs) was <1 indicating no risk. HIA, resulting from the sum of all HQs was found HIA < 1 in nine out of ten toxicity groups, except to the neurotoxicity group, which presented HIA 2.258, indicating moderate risk.


Assuntos
Contaminação de Alimentos/análise , Fungicidas Industriais/análise , Inseticidas/análise , Malus/química , Resíduos de Praguicidas/análise , Cromatografia Líquida/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Grécia , Medição de Risco , Espectrometria de Massas em Tandem/métodos
15.
Toxicol Rep ; 6: 632-636, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31334033

RESUMO

A hazard quotient (HQ) for a single chemical and the hazard index (HI) for a mixture of chemicals were first described as approaches for risk characterisation by the EPA. HQ is defined as the ratio of exposure to an appropriate reference dose such as the ADI. HI is the sum of the HQs of the chemicals in a mixture. HQ and HI have been used to characterise risk after various exposure scenarios. However, both approaches have a significant limitation in the way they are used. The accurate use of HQ or HI requires estimation of aggregate exposure, that is, exposure to a given chemical(s) from all possible relevant sources. In many studies, risk is assessed assuming exposure from a specific source such as, consumption of water or a specific food item, in which chemical(s) concentration(s) have been measured. In this case the classic HQ/HI approach can result in significant underestimation of risk. For this purpose, we developed an alternative approach, named as Source Related HQ (HQs) where HQS is the ratio of the exposure from the specific source of interest to the respected reference values. According to our approach the HQS, before being compared to the reference dose, should be adjusted by a correction factor, in order to simulate aggregated exposure. A correction factor can be calculated based on the permitted exposure contribution from the specific source to the permitted aggregated exposure. Another important limitation specific to the HI approach is the use of chemical specific ADIs that do not correspond to the same critical effect. In this study, we present an analysis based on the individual critical effects, in order to derive the critical effect and an adversity specific Hazard Index (HIA) and risk characterisation for the whole mixture.

16.
Toxicol Lett ; 313: 91-100, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31128211

RESUMO

Iran is a major supplier of the world pistachio market. In this study, we collected five pistachio cultivars from four main pistachio-producing zones in August and September 2016, and determined the residues of 18 organophosphorus, carbamate, pyrethroid and nicotinoid pesticide in these samples using Gas Chromatography-Mass Spectrometry, as an efficient method for determination of pesticides' residues. Next, single-chemical and chronic cumulative risk assessment was done based on the new approaches of the food specific Hazard Quotient and adversity specific Hazard Index. Fifteen from eighteen food-specific Hazard Quotients were above 1 even in cases when the respective contamination was bellow MRLs. The adversity specific Hazard Indexes values were above 1 for five from six adversities indicating various risks in the resulted levels of pistachios' contamination from the pesticides' mixture. However, no risk for carcinogenicity was found. Our results indicate the necessity of taking appropriate measures to control/standardize pesticides practice in pistachio cultivation in Iran and the need to re-establish the MRLs based on cumulative exposure.


Assuntos
Simulação por Computador , Produtos Agrícolas/efeitos adversos , Contaminação de Alimentos , Modelos Teóricos , Nozes/efeitos adversos , Resíduos de Praguicidas/efeitos adversos , Pistacia/efeitos adversos , Qualidade de Produtos para o Consumidor , Produtos Agrícolas/classificação , Produtos Agrícolas/crescimento & desenvolvimento , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Irã (Geográfico) , Nozes/classificação , Nozes/crescimento & desenvolvimento , Resíduos de Praguicidas/análise , Pistacia/classificação , Pistacia/crescimento & desenvolvimento , Medição de Risco , Fatores de Tempo
17.
Toxicol Lett ; 310: 70-91, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30999039

RESUMO

The aim of the current study was to evaluate the effects of a mixture of thirteen common chemicals on rats, after a one-year exposure to doses around the acceptable daily intake (ADIs), using blood and urinary tests. The influence of low doses of the mixture on weight gain, water consumption, feed consumption and feed efficiency, biochemistry parameters, haematological parameters, blood lymphocytes subsets, serum inflammation profile and urine parameters was evaluated. Our mixture caused a moderate monotonic increase of the males' appetite and a non-monotonic increase of anabolism and a monotonic increase of appetite for the females. Regarding biochemical parameters, the exposure to the test mixture caused non-monotonic increases of AST and ALT, a decrease of PChE in males and plausibly a monotonic biliary obstruction in both sexes. Monocytes significantly increased in low dose groups of both sexes. A significant decrease of all the lymphocytes subclasses and an increased expression of TNF-α protein associated with an increased expression of IFN-γ protein observed in various groups. It became apparent that after twelve months of exposure very low doses of the tested mixture had both non-monotonic and monotonic harmful effects on different levels on rats.


Assuntos
Misturas Complexas/toxicidade , Aditivos Alimentares/toxicidade , Praguicidas/toxicidade , Testes de Toxicidade Crônica , Animais , Regulação do Apetite/efeitos dos fármacos , Biomarcadores/sangue , Biomarcadores/urina , Colestase/induzido quimicamente , Citocinas/sangue , Citocinas/urina , Ingestão de Líquidos/efeitos dos fármacos , Ingestão de Alimentos/efeitos dos fármacos , Feminino , Hormese , Mediadores da Inflamação/sangue , Mediadores da Inflamação/urina , Linfócitos/efeitos dos fármacos , Linfócitos/metabolismo , Masculino , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Ratos Sprague-Dawley , Medição de Risco , Fatores de Tempo , Aumento de Peso/efeitos dos fármacos
18.
Food Chem Toxicol ; 127: 260-269, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30898530

RESUMO

Health benefits of fish consumption could be counterbalanced by the intake of contaminants after long term fish consumption, burdened even in trace levels. The presence of the indicator PCBs (NDL-PCBs and PCB 118) in farmed and wild seabream and seabass was evaluated. For the determination of PCB, a GC-MS method was developed and evaluated. The association of PCB accumulation in fish with seasonality, locality, production mode and species was also investigated. A new approach for the risk characterisation after exposure to NDL-PCB through fish consumption in Greece was developed, based on the real exposure and the permitted maximum levels of both aggregated dietary exposure and exposure through fish consumption. PCB levels determined in fish were below established permitted limits (6.24 ng/g 95th percentile), while PCB levels and congener distribution varied significantly between farmed and wild fish (p = 0.001). Seasonality was highlighted as an important factor affecting NDL-PCBs accumulation, with high levels coinciding with the reproduction period of each species. Differences were also depicted for sampling sites, with PCB 118 presenting significantly higher values in open seas while NDL-PCB congeners in closed seas. Risk assessment of NDL-PCB intake through fish consumption corrected for the aggregated exposure revealed no risk for the consumers.


Assuntos
Aquicultura , Exposição Dietética , Peixes , Contaminação de Alimentos/análise , Bifenilos Policlorados/análise , Alimentos Marinhos/análise , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Animais , Cromatografia Gasosa-Espectrometria de Massas , Grécia , Humanos , Limite de Detecção , Lipídeos/análise , Reprodutibilidade dos Testes , Medição de Risco , Estações do Ano
19.
Toxicol Rep ; 6: 105-110, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30622904

RESUMO

Effects of technical materials of pesticide active ingredients, belonging to various chemical classes, on erythropoiesis in mouse bone marrow were studied as part of the research on the pesticide mutagenic activity in micronucleus test. The purpose of the present study was to estimate the toxic action of the test substances on the target organ and the validity of the results of the micronucleus assay under conditions of erythropoiesis suppression. It was demonstrated that intragastrically administrated triazole pesticides reached bone marrow (target organ where micronucleus induction was assessed) and exerted an inhibitory effect on erythropoiesis. The effects of triazole pesticides were enhanced in the following order: difenoconazole ≤ tebuconazole < cyproconazole < flutriafol. Furthermore, an association between structural features of molecules and specific target organ activity of the test pesticides was observed. Based on the data on the general toxicity and the results of the evaluation of the effects on erythropoiesis, the maximum tolerated doses (MTDs) of 79 different technical materials of pesticides for CD-1 mice were determined.

20.
World Acad Sci J ; 1(4): 157-164, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32346674

RESUMO

Research over the past years has indicated that chronic human exposure to very low doses of various chemical species in mixtures and administered via different routes (percutaneous, orally, etc.) should be the main focus of new biochemical and toxicological studies. Humans have daily contact with various chemicals, such as food additives, pesticides from fruits/vegetables, antibiotics (and other veterinary drugs) from meat, different types of preservatives from cosmetics, to name a few. Simultaneous exposure to this wide array of chemicals does not produce immediate effects, but summative effect/s over time that may be clinically manifested several years thereafter. Classical animal studies designed to test the toxic outcome of a single chemical are not suitable to assess, and then extrapolate to humans, the effects of a whole mixture of chemicals. Testing the aftermath of a combination of chemicals, at low doses, around or below the no observed adverse effect is stressed by many toxicologists. Thus, there is a need to reformulate the design of biochemical and toxicological studies in order to perform real-life risk simulation. This review discuss the potential use of computational methods as a complementary tool for in vitro and in vivo toxicity tests with a high predictive potential that could contribute to reduce animal testing, cost and time, when assessing the effects of chemical combinations. This review focused on the use of these methods to predict the potential endocrine disrupting activity of a mixture of chemicals.

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