Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 26
Filtrar
Mais filtros

Bases de dados
Tipo de documento
Intervalo de ano de publicação
1.
Artigo em Inglês | MEDLINE | ID: mdl-38315775

RESUMO

Garri is a granular, starchy food prepared by the fermentation of mashed cassava. Hydrogen cyanide (HCN) and mycotoxins are contaminants in certain foods at different points along the food value chain. The incidence and contamination levels of HCN and multi-mycotoxins in garri from five agroecological zones of Nigeria were determined using a spectrophotometric method and ultra-high-performance liquid chromatography-tandem mass spectroscopy (UHPLC-MS/MS), respectively. The health risk associated with the consumption of contaminated garri was assessed. The health risk assessment model was used to calculate the dietary exposure of humans to the mycotoxins in garri. This was done by estimating the daily intake (EDI), the percentage tolerable daily intake (%TDI), the annual hepatocellular carcinoma (HCC) cases attributable to exposure to aflatoxins (AFs) in garri, as well as the HCC risk. The average intake of garri was estimated at 0.303 kg/day for a Nigerian adult. The incidence of HCN was 98.3% (0.056-2.463 mg/kg), and fermentation reduced the HCN level in garri more than other processing steps. The twenty-one mycotoxins identified and quantified were all within maximum levels, as applicable to those that are regulated by the EU. The %TDI for the other mycotoxins, with the exception of AFs, showed no alarming health risk with garri consumption. Annual HCC cases resulting from AF in garri were estimated at 10-60 cases for HBsAg + ve individuals and 4-23 cases for HBsAg - ve individuals based on 8.1% hepatitis B virus (HBV) incidence. Results further revealed no interdependence between HCN levels and mycotoxin content. This work suggests an unlikely chance of acute toxicity from HCN and major mycotoxins from a garri-based diet in Nigeria. Hence, it is recommended that concerned regulatory bodies maintain the existing permissible limits for HCN in Garri.


Assuntos
Aflatoxinas , Carcinoma Hepatocelular , Neoplasias Hepáticas , Micotoxinas , Adulto , Humanos , Micotoxinas/análise , Cianeto de Hidrogênio , Espectrometria de Massas em Tandem , Antígenos de Superfície da Hepatite B , Incidência , Neoplasias Hepáticas/epidemiologia , Aflatoxinas/análise , Contaminação de Alimentos/análise , Medição de Risco
2.
Sci Total Environ ; 898: 165492, 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37453708

RESUMO

Artisanal and small-scale gold mining (ASGM) is the leading global source of anthropogenic mercury (Hg) release to the environment. Top-down mercury reduction efforts have had limited results, but a bottom-up embrace of cyanide (CN) processing could eventually displace mercury amalgamation for gold recovery. However, ASGM transitions to cyanidation nearly always include an overlap phase, with mercury amalgamation then cyanidation being used sequentially. This paper uses a transdisciplinary approach that combines natural and social sciences to develop a holistic picture of why mercury and cyanide converge in gold processing and potential impacts that may be worse than either practice in isolation. We show that socio-economic factors drive the comingling of mercury and cyanide practices in ASGM as much or more so than technical factors. The resultant Hg-CN complexes have been implicated in increasing the mobility of mercury, compared to elemental mercury used in Hg-only processing. To support future inquiry, we identify key knowledge gaps including the role of Hg-CN complexes in mercury oxidation, transport, and fate, and possible links to mercury methylation. The global extent and increase of mercury and cyanide processing in ASGM underscores the importance of further research. The immediacy of the problem also demands interim policy responses while research advances, though ultimately, the well-documented struggles of mercury reduction efforts in ASGM temper optimism about policy responses to the mercury-cyanide transition.

3.
Environ Monit Assess ; 195(4): 482, 2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36930367

RESUMO

Improper discharge of cassava mill effluent (CME) has attracted much attention in major cassava-producing areas due to cyanide contamination. This study conducted a target survey on inhabitants and processors of the Akrofrom-Techiman cassava processing area in Ghana that aimed to assess their knowledge and perception of cyanide contamination from the CME discharge. The study further examined the effect of CME on the soil and groundwater at the processing area using physicochemical and bacteriological characterizations. Results revealed that inhabitants and processors exhibited high illiteracy on the impact of CME on cyanide contamination in the processing area. The study also indicated a wide characteristics of the soil at the processing site: pH (4.89-8.77), electrical conductivity (EC) (1063.00-1939.00 µS/cm), total dissolved solids (TDS) (523.90-963.50 mg/L), soil moisture (11.90-31.70%), free cyanide (0.02-0.33 mg/kg), and total cyanide (0.40-2.70 mg/kg). Results also showed that the physicochemical values of the CME were all above the Ghana Environmental Protection Agency (EPA) permissible limits and were unsafe for discharging into the environment. The range of physicochemical and bacteriological parameters of the two boreholes revealed the following: pH (7.85-8.74), TDS (165.77-192.37 mg/L), EC (320.87-396.20 µS/cm), free cyanide (0.13-0.16 mg/L), total cyanide (1.29-2.15 mg/L), and bacteriological parameter (220-622 cfu/mL). The two hand-dug wells also recorded pH (8.54-9.56), TDS (140.77-156.10 mg/L), EC (288.53-340.67), biological oxygen demand (BOD) (21.51-1.61 mg/L), chemical oxygen demand (COD) (13.5-16.5 mg/L), free cyanide (0.10-0.11 mg/L), bacteriological parameter (241-302 cfu/mL), and total cyanide (0.79-0.86 mg/L). The study concluded that the discharge of CME at the processing site contributes significantly to cyanide contamination of the soil and groundwater at the processing area.


Assuntos
Água Subterrânea , Manihot , Poluentes Químicos da Água , Cianetos , Monitoramento Ambiental , Gana , Poluentes Químicos da Água/análise , Solo
4.
Birth Defects Res ; 115(7): 722-752, 2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-36843237

RESUMO

BACKGROUND: The National Toxicology Program (NTP, 1993) reported male reproductive effects in a sodium cyanide (NaCN) drinking water study. The critical effect, decreased cauda epididymis weights, was used by U.S. Environmental Protection Agency for their hazard characterization and risk assessment of hydrogen cyanide and cyanide salts. To further investigate potential male reproductive effects, we conducted a new 90-day drinking water study. METHODS: Our study expanded evaluations of testes and thyroid. Male F344 rats received NaCN in drinking water at 0, 0 (water restricted; paired to top dose), 3, 10, 30, 100, and 300 ppm for 13 weeks, followed by 10-weeks recovery. RESULTS: Plasma thiocyanate increased dose-dependently but returned to baseline during recovery. NaCN caused neither effects on survival, body weight, food consumption, hematology, serum chemistry, urinalysis, thyroid hormones, testes or epididymides weights, sperm motility/viability, sperm morphology, or sperm production; nor clinical, ophthalmic, or histopathologic findings. Increased organ weights in thyroid/parathyroid and liver occurred at 300-ppm but were recoverable. No changes occurred in male reproductive organs. CONCLUSIONS: Absent adverse effects, the NOAEL was 300 ppm (21.66 mg/kg/day; highest dose tested). Based on organ weight increases at 300 ppm, the NOEL was 100 ppm (7.46 mg/kg/day).


Assuntos
Água Potável , Estados Unidos , Ratos , Masculino , Animais , Ratos Endogâmicos F344 , Água Potável/efeitos adversos , Cianeto de Sódio/farmacologia , Motilidade dos Espermatozoides , Sêmen , Medição de Risco
5.
Birth Defects Res ; 115(7): 687-709, 2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-36797649

RESUMO

BACKGROUND: Based on new testing, we re-assess U.S. EPA and California OEHHA conclusions regarding male reproductive toxicity associated with cyanide exposure. METHODS: Literature identified by ATSDR, ECETOC and EPA was complemented by studies conducted after 2006. Relevant studies were scored for quality using ToxRTool. RESULTS: Eleven pertinent animal investigations were identified; five with quality scores of 1 were evaluated in-depth. The NTP 13-week drinking water study of NaCN in rats reported significantly decreased water intakes and reduced cauda epididymal weights; altered sperm parameters occurred in high-dose rats. When compared to contemporaneous historical control data (HCD), the mean cauda epididymal weights of cyanide-treated rats in the NTP study were within HCD, whereas control weights exceeded HCD. A new 13-week drinking water study used the same design with additional features (individually caged rats, "paired water" controls, thyroid hormone determinations, post-treatment recovery) and found a smaller decrease in water consumption (11% versus 18% at 300 ppm) and no treatment-related changes in male reproductive measures. Although thyroid/parathyroid weights were increased at 300 ppm, histopathology and thyroid hormone levels were unaffected. The remaining high-quality cyanide studies reported no adverse findings in male reproductive organs. Unconfounded sperm measures were not adversely affected in any quality 1 studies. CONCLUSIONS: Changes in the male reproductive system reported after cyanide exposure in the NTP study were not reproducible, unlikely to be treatment-related, and should not be used as the sole basis for human health assessments.


Assuntos
Água Potável , Humanos , Ratos , Masculino , Animais , Cianetos/toxicidade , Sêmen , Testículo/patologia , Reprodução
6.
Foods ; 11(19)2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36230125

RESUMO

The presence of potentially hazardous substances in fruit wines poses a threat for human health. However, the management standards and specifications of hazardous substances contained within various types of fruit wines are currently insufficient. The aim of this study was to analyze hazardous substances (cyanide, acetaldehyde, and ethyl carbamate) and quality control characteristics (pH, titratable acidity, sulfur dioxide, and diacetyl) in seven different types of fruit wines. The pH levels and titratable acidity varied between fruit wine types. In all fruit wines, sulfur dioxide (SO2) was within acceptable ranges as per the Korean standard. Acetaldehyde content also varied between fruit wine types as well as based on the analytical method (titration or enzymatic analysis) employed. Cyanide was in the range of 0.02−0.35 mg/L. Diacetyl contents were in the range of 0.66−2.95 mg/L (p > 0.05). The contents of ethyl carbamate varied considerably, within the range of 5.22−259.69 µg/kg (p < 0.05). The analytical methods of diacetyl and ethyl carbamate were validated for specificity, linearity, sensitivity, accuracy, and precision. Therefore, the content of hazardous substances and quality control characteristics should be closely monitored and controlled to improve safety and quality of the traditional fruit wines.

7.
Leg Med (Tokyo) ; 59: 102111, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35802996

RESUMO

Recently, 2-aminothiazoline-4-carboxylic acid (ATCA), a cyanide (CN) metabolite, has been proposed as a stable diagnostic marker of CN poisoning. In this study, liquid chromatography coupled with electrospray ionization - tandem mass spectrometry was used to quantify ATCA concentrations in human postmortem blood samples, and differences in ATCA concentrations according to age and sex were determined. Both age and sex had significant effects on blood ATCA concentrations. Although ATCA concentrations exhibited an inverted U shape with increasing age in men, in women ATCA concentrations plateaued at around 40-59 years of age. There were significant differences between the sexes in ATCA concentrations for the 20-39 and 40-59 year age groups (P < 0.05 and P < 0.01, respectively). Correlations between ATCA concentrations and carboxyhemoglobin (CO-Hb) saturation were also examined in fire victims. ATCA concentrations increased significantly with increasing CO-Hb saturation (r = 0.382, P < 0.01). In addition, ATCA concentrations were also correlated to CN concentrations (r = 0.309, P < 0.05). The results of our study may provide novel information about the contribution of CN poisoning to the cause of death at fire scenes.


Assuntos
Carboxihemoglobina , Cianetos , Incêndios , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carboxihemoglobina/análise , Ácidos Carboxílicos , Cianetos/intoxicação , Caracteres Sexuais , Adulto Jovem , Autopsia
8.
Anal Sci ; 38(2): 437-442, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35286634

RESUMO

Cyanide is highly toxic to humans and the environment. It is very important to develop an on-site system for the quantitative analysis of cyanide with high sensitivity and reliability. In this study, we developed a cyanide detection system based on the reaction of vaporized cyanide on a glass-fiber filter soaked in a mixture of naphthalene-2,3-dicarboxaldehyde (NDA)-taurine-borate solution. Although the reaction product was stable for at least 3 days at room temperature, the reaction product on the strip was quickly quenched within a few minutes by direct irradiation with 405 nm light. To overcome this problem, we fabricated a simple device designed to detect the fluorescence intensity immediately after inserting a reaction strip into the device. The linearity of the calibration was obtained over a range of 1-100 µM of cyanide with good repeatability. The device is cost-effective (~ $300) and powered by batteries; therefore, it is suitable for the on-site determination of cyanide in crude samples.


Assuntos
Cianetos , Lasers , Análise Custo-Benefício , Cianetos/análise , Humanos , Reprodutibilidade dos Testes , Espectrometria de Fluorescência
9.
Burns ; 48(6): 1325-1330, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-34903402

RESUMO

BACKGROUND & OBJECTIVES: Cyanide poisoning can occur due to exposure to smoke in closed-space fires. With no point of care cyanide test at the scene of a fire, first responders and clinicians base decisions to treat with cyanide antidote on patient history, clinical signs, and other indirect data points that have not been proven to correspond with actual systemic levels of cyanide. The aim of this exploratory study was to determine the economic implications of treating patients with known or suspected cyanide poisoning due to smoke inhalation with hydroxocobalamin. METHODS: A decision analysis model was developed from the US hospital perspective. Healthcare resource utilization was estimated from a retrospective evaluation of clinical outcomes in hydroxocobalamin-treated patients and in historical controls without hydroxocobalamin use (Nguyen, et al. 2017). Epidemiologic parameters and costs were estimated from the published literature, and publicly-available hospital charges were identified. Outcomes reported in the analysis included expected healthcare resource utilization in the US population and per-patient costs with and without the use of hydroxocobalamin. A cost-to-charge ratio was applied so that all costs would reflect hospital costs rather than hospital charges. Deterministic sensitivity analysis was performed to identify the most influential model parameters. All costs were reported in 2017 US dollars. RESULTS: Use of hydroxocobalamin reduces healthcare resource utilization and contributes to decreased per-patient hospital costs ($15,381 with hydroxocobalamin treatment versus $22,607 with no cyanide antidote). The most substantive cost-savings resulted from decreased hospital length of stay (i.e., intensive care unit [ICU] and non-ICU). Costs attributed to mechanical ventilation also decreased with use of hydroxocobalamin. A univariate sensitivity analysis demonstrated that the most impactful variables in the cost analysis were related to hospital length of stay (ICU followed by non-ICU stay), followed by the daily cost of ICU stay. CONCLUSIONS: Use of hydroxocobalamin in patients with known or suspected cyanide poisoning from closed-space fire smoke inhalation may decrease hospital costs and contribute to more efficient healthcare resource utilization.


Assuntos
Queimaduras , Incêndios , Lesão por Inalação de Fumaça , Antídotos/uso terapêutico , Queimaduras/tratamento farmacológico , Cianetos , Humanos , Hidroxocobalamina/uso terapêutico , Estudos Retrospectivos , Lesão por Inalação de Fumaça/tratamento farmacológico , Fumar
10.
Environ Monit Assess ; 193(8): 483, 2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34241745

RESUMO

This work investigated heavy metal and cyanide pollution in surface soils and edible plants around Yanzhuang gold tailings ponds in the region of Yanzhuang Village in Pinggu District, Beijing. Surface soil samples were collected from 33 sites around gold tailings ponds, and concentrations of seven heavy metals (i.e., Sb, As, Cd, Cu, Pb, Zn, and Hg) and cyanide were analyzed to determine their spatial distributions, pollution degrees, and sources. The potential ecological risks of As, Cd, Cu, Pb, Zn, and Hg were preliminarily assessed. The results showed that the mean cyanide, Sb, As, Cd, Cu, and Pb concentrations were higher than the standard values. The pollutant concentrations around the tailings ponds were high and decreased with increasing distance from the ponds. The single pollution index indicated that cyanide, As, and Cd were the main pollutants. The Nemerow pollution index revealed a large region and serious degree of heavy metal pollution in soils. The potential ecological risk level of the study area was moderate, with Cd and As posing the main risks. Multivariate statistical analysis suggested that the heavy metal and cyanide pollution present mainly derived from gold tailings, with agricultural pollution also had a certain effect. However, the 12 edible plants sampled were basically not polluted.


Assuntos
Poluentes Ambientais , Metais Pesados , Poluentes do Solo , Pequim , China , Monitoramento Ambiental , Ouro , Metais Pesados/análise , Lagoas , Medição de Risco , Solo , Poluentes do Solo/análise
11.
Food Chem ; 354: 129405, 2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-33770563

RESUMO

The intake of cassava would probably induce adverse health effects since there are toxic cyanide in cassava. However, the risk assessment of cassava consumption has not been reported in China. Therefore, this paper aimed to evaluate the dietary risks of cassava cyanide and proposed a maximum residue limit (MRL) for cyanogenic glycosides (CNGs) in cassava. The retention rate of CNGs and CN- were 61% and 11% after boiling, respectively. The acute dietary exposure of CN- and CNGs were 0.6-fold and 1.7-fold of acute risk reference dose, respectively. There was no chronic health risk across all populations concerning cassava consumption. The MRL of CNGs was proposed as 200 mg/kg in cassava. Risk assessment of cyanide for foods rich in CNGs was suggested to be based on CNGs quantification rather than that of CN-.


Assuntos
Cianetos/análise , Exposição Dietética , Manihot/química , China , Cromatografia Líquida de Alta Pressão , Culinária , Glicosídeos/análise , Humanos , Manihot/metabolismo , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Medição de Risco , Espectrometria de Massas em Tandem
12.
J Forensic Sci ; 66(3): 1171-1175, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33369895

RESUMO

Hydrogen cyanide (HCN) can be a major contributory factor in death from fire-related inhalation injury. Although carbon monoxide (CO) is considered the lethal agent of smoke in fires, its liability as a cause of death is sometimes debatable. The purpose of this report is to present the case of an 80-year-old man with locomotor disabilities who died due to an open space fire of vegetation debris and household waste in his yard. We evaluated here the concentrations of HCN and carboxyhemoglobin (COHb) and their contribution to the mechanism of death. In addition, the risk factors and the contributing effect of the factors that compose the complex toxic environment that develops in fires were discussed. COHb was determined by spectrophotometry as recommended by Katsumata et al. in 1982. HCN was determined with ninhydrin in postmortem blood samples after removal with 20% phosphoric acid and capture in a potassium carbonate solution. A toxic concentration of 1.3 µg ml-1 HCN and a lethal COHb level of 73.7% were determined in the blood samples. Although death was mainly attributed to CO poisoning and extremely severe burns in this open space burning case, the additive effect of HCN in the mechanism of death was also highlighted. The results suggested the possibility that the man's clothing may have played an important role in the production of HCN in this open space fire, as well as other types of garbage that were burned.


Assuntos
Carboxihemoglobina/análise , Incêndios , Cianeto de Hidrogênio/sangue , Idoso de 80 Anos ou mais , Queimaduras/etiologia , Intoxicação por Monóxido de Carbono/diagnóstico , Medicina Legal , Humanos , Masculino , Limitação da Mobilidade , Espectrofotometria
13.
Phytochemistry ; 174: 112330, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32146386

RESUMO

10 primers each of random amplified polymorphic DNA (RAPD), inter-simple sequence repeats (ISSR), inter primer binding site (iPBS) and start codon targeted (SCoT) were used to analyze genetic polymorphism and relationship between 50 genotypes of 5 economical important native bamboos (Bambusa cacharensis, B. mizorameana, Dendrocalamus manipureanus, D. hamiltonii and D. sikkimensis) of North-East India. The 40 different primers generated 111, 115, 116 and 138 polymorphic bands for RAPD, ISSR, iPBS and SCoT markers respectively. The comparative analysis of 4 marker systems based on polymorphic information content (PIC), effective multiplex ratio (EMR) and marker index (MI) values showed SCoT to be more informative with higher discriminating power than the other three markers. The correlation value (r) as determined by the Mantel test ranged from 0.60 (SCoT and RAPD) to 0.83 (iPBS and ISSR) indicating a high positive correlation between the markers. The close correspondence between the genetic matrices of RAPD, ISSR, iPBS and SCoT markers revealed the effectiveness of each marker system in determining the genetic relationship between bamboos. UPGMA (Unweighted Pair Group Arithmetic Mean Method) dendrograms generated from DNA marker analysis demonstrated species-specific clustering of different bamboo genotypes. Except for RAPD, the dendrograms of ISSR, iPBS and SCoT markers also showed a close association of bamboo genotypes based on geographical origin. Principal coordinate analysis (PCoA) revealed the distribution of different bamboo genotypes in accordance with the cluster analysis. The cluster grouping based on phytochemical study not only discriminated the different bamboo species but also illustrated a location-specific grouping of the genotypes. The bamboo clustering pattern derived from phytochemical analysis matched closely with the dendrograms generated by the DNA markers. The present investigation established the possibility of using a combined molecular and phytochemical marker approach to determine the genetic relationship between 5 native bamboos of North-East India with high precision.


Assuntos
Variação Genética , Repetições de Microssatélites , Sítios de Ligação , Códon de Iniciação , DNA , Índia , Filogenia , Compostos Fitoquímicos , Técnica de Amplificação ao Acaso de DNA Polimórfico
14.
Talanta ; 207: 120278, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31594612

RESUMO

Cyanide is potentially hazardous and quickly acting chemical used in many fields of industry. Therefore, detection of cyanide is of main health concern due to its serious impacts on living organisms. In this context, we have developed rapid, low-cost and on-site sensory two molecules for the colorimetric and fluorogenic sensing of cyanide ion in aqueous samples and food samples. The prepared probes undergo distinct visual color change and exhibits selective fluorogenic turn-on or turn-off response towards cyanide. Competing anions have little or negligible effect on the detection of cyanide. The limit of detection for cyanide ion was calculated as low as 0.45 µM. Free receptors could be successfully regenerated by treating them with Ag+ ion. Moreover, a new visual colorimetric strip based on paper was fabricated with the pale yellow-to-pink color change signal. The fabricated test strips also demonstrated excellent selectivity towards cyanide ion without interfering possible fluoride and acetate ions. The smartphone-based technique which could directly read out the color value using a smartphone revealed an excellent potential for the cyanide detection without additional device.


Assuntos
Colorimetria/economia , Colorimetria/instrumentação , Custos e Análise de Custo , Cianetos/análise , Corantes Fluorescentes/química , Smartphone , Cianetos/química , Limite de Detecção , Modelos Moleculares , Conformação Molecular , Fitas Reagentes/química , Fatores de Tempo , Água/química
15.
Toxicol Ind Health ; 35(6): 410-423, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31244408

RESUMO

Cyanide is an important industrial pollutant, major occupational hazard, and a potential chemical warfare agent. Its intentional or accidental exposure to humans is a big clinical problem because of its rapid mode of action. Certain plant origin foods also contain substantial amount of cyanide and cause chronic toxicity. This study explores the protective efficacy of co-treatment of alpha-ketoglutarate (AKG) and an antioxidant N-acetyl cysteine (NAC) against toxicity of subchronically exposed cyanide in rats. We explore the effect of AKG + NAC co-treatment on oxidative stress, inflammation, and histological changes induced due to long-term sublethal cyanide exposure. Cyanide induces oxidative stress by inhibiting metalloenzymes (catalase and superoxide dismutase) causing increase in lipid peroxidation (malondialdehyde) and decrease in reduced glutathione (GSH). It also increases the activity of cyclo-oxygenase enzymes causing oxidative stress-mediated inflammation in the brain. Cyanide exposure also causes degenerative changes in the brain as shown in histology. It also causes pathology in liver and kidney. AKG is known to form cyanohydrins with cyanide reducing the free cyanide levels, and its combination with NAC showed overall improvement in by reducing the oxidative stress and subsequent neuroinflammation. Their combination was also found to improve the histological outcome of vital tissues. AKG, an over-the-counter sport medicine, and the antioxidant NAC per se did not show any detrimental effects in any tested parameter. Hence, oral treatment with AKG and NAC can be beneficial for the treatment of chronic cyanide poisoning.


Assuntos
Acetilcisteína/farmacologia , Cianetos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Ácidos Cetoglutáricos , Rim/efeitos dos fármacos , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Ratos , Ratos Wistar
16.
J Toxicol Sci ; 44(3): 201-211, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30842372

RESUMO

This study was aimed to predict drug-induced liver injury caused by reactive metabolites. Reactive metabolites covalently bind to proteins and could result in severe outcomes in patients. However, the relation between the extent of covalent binding and clinical hepatotoxicity is still unclear. From a perspective of body burden (human in vivo exposure to reactive metabolites), we developed a risk assessment method in which reactive metabolite burden (RM burden), an index that could reflect the body burden associated with reactive metabolite exposure, is calculated using the extent of covalent binding, clinical dose, and human in vivo clearance. The relationship between RM burden and hepatotoxicity in humans was then investigated. The results indicated that this RM burden assessment exhibited good predictability for sensitivity and specificity, and drugs with over 10 mg/day RM burden have high-risk for hepatotoxicity. Furthermore, a quantitative trapping assay using radiolabeled trapping agents ([35S]cysteine and [14C]KCN) was also developed, to detect reactive metabolite formation in the early drug discovery stage. RM burden calculated using this assay showed as good predictability as RM burden calculated using conventional time- and cost-consuming covalent binding assays. These results indicated that the combination of RM burden and our trapping assay would be a good risk assessment method for reactive metabolites from the drug discovery stage.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Medição de Risco/métodos , Carga Corporal (Radioterapia) , Cisteína/metabolismo , Descoberta de Drogas , Humanos , Microssomos Hepáticos/metabolismo , Preparações Farmacêuticas/metabolismo , Cianeto de Potássio/metabolismo
17.
Sci Total Environ ; 648: 693-702, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30125851

RESUMO

Ecological Risk Assessment of chemicals in fluvial systems is a highly researched topic, but its importance for the environmental protection of our planet is vital. Thus, new developments and improvements to existing methodologies are proposed constantly, for providing more advanced tools and more accurate results to researchers and other interested parties. In the field of probabilistic Ecological Risk Assessment, a new Decision Support System is proposed, developed, tested and evaluated. The AMORE DSS is a modular DSS, which incorporates a series of new methodologies, and is built upon the notions of 'Exposure Assessment', 'Effect Assessment' and 'Risk Assessment'. The AMORE Decision Support System has been developed as part of the AMORE research project (French National Research Agency project). The DSS provides a set of tools for analysing and integrating both exposure and effect information in order to evaluate the risk for species living on a given contaminated aquatic system in terms of the Potentially Affected Fraction. The DSS has been tested through a case study on ERA of cyanide in the watershed of river Selune in France. The paper presents the 'Exposure Assessment' and 'Risk Assessment' of the cyanide case study, as well as the complete functionalities of the AMORE DSS. The main results presented in the paper are the statistical analysis of the measured environmental concentrations of cyanide (Exposure Assessment) and the probabilistic 'Risk assessment' of the same contaminant in the area of interest, based on the functionalities of the DSS. The results are described and discussed in detail with the use of various graphs and risk indices. The risk indices are calculated for all the available ecotoxicological data, as well as for the data on trophic levels or taxonomic groups separately. A risk comparison is presented between the innovative methodologies included in the DSS and the currently existing methodologies.

18.
Sci Total Environ ; 648: 1665-1672, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30172483

RESUMO

Ecotoxicological data are highly important for risk assessment processes and are used for deriving environmental quality criteria, which are enacted for assuring the good quality of waters, soils or sediments and achieving desirable environmental quality objectives. Therefore, it is of significant importance the evaluation of the reliability and relevance of available data for analysing their possible use in the aforementioned processes. In this context, a new methodology which has been developed based on Multi-Criteria Decision Analysis (MCDA) techniques, is being used, demonstrated and tested for analysing the reliability and relevance of ecotoxicological data of cyanide (which are produced through laboratory biotests for individual effects). The proposed methodology is also used for the production of Weighted by Data Quality Species Sensitivity Distributions (SSD-WDQ), as a component of the Ecological Risk Assessment of chemicals in aquatic systems. The SSD-WDQ production resulted in the estimation of environmental quality criteria (hazard concentration affecting 5% and 50% of the species). The proposed work is part of the development of the AMORE Decision Support System (DSS) for the application of probabilistic Ecological Risk Assessment (ERA), presented in the companion paper (Isigonis et al., 2019). The DSS has been tested through a case study on ERA of cyanide in the watershed of river Selune in France. The paper presents the 'Effect Assessment' of cyanide, based on the aforementioned methodologies. The main results presented in the paper are the probabilistic analysis of the estimated species sensitivity on cyanide (Effect Assessment) and the calculation of Hazardous Concentration (HCx) of the same contaminant in the Selune river area, based on the functionalities of the DSS. The results are described and discussed in detail, with the use of various graphs and indices. The indices are calculated for all the available ecotoxicological data, as well as for the data on trophic levels or taxonomic groups separately. An effect comparison is presented between the innovative methodologies included in the DSS and the currently existing methodologies.

19.
Free Radic Biol Med ; 129: 146-154, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30213640

RESUMO

RATIONALE: Cystic fibrosis (CF) patients are known to produce cyanide (CN-) although challenges exist in determinations of total levels, the precise bioactive levels, and specificity of its production by CF microflora, especially P. aeruginosa. Our objective was to measure total CN- levels in CF sputa by a simple and novel technique in P. aeruginosa positive and negative adult patients, to review respiratory tract (RT) mechanisms for the production and degradation of CN-, and to interrogate sputa for post-translational protein modification by CN- metabolites. METHODS: Sputa CN- concentrations were determined by using a commercially available CN- electrode, measuring levels before and after addition of cobinamide, a compound with extremely high affinity for CN-. Detection of protein carbamoylation was measured by Western blot. MEASUREMENTS AND MAIN RESULTS: The commercial CN- electrode was found to overestimate CN- levels in CF sputum in a highly variable manner; cobinamide addition rectified this analytical issue. Although P. aeruginosa positive patients tended to have higher total CN- values, no significant differences in CN- levels were found between positive and negative sputa. The inflammatory oxidant hypochlorous acid (HOCl) was shown to rapidly decompose CN-, forming cyanogen chloride (CNCl) and the carbamoylating species cyanate (NCO-). Carbamoylated proteins were found in CF sputa, analogous to reported findings in asthma. CONCLUSIONS: Our studies indicate that CN- is a transient species in the inflamed CF airway due to multiple biosynthetic and metabolic processes. Stable metabolites of CN-, such as cyanate, or carbamoylated proteins, may be suitable biomarkers of overall CN- production in CF airways.


Assuntos
Cianetos/análise , Fibrose Cística/metabolismo , Técnicas Eletroquímicas , Ácido Hipocloroso/química , Processamento de Proteína Pós-Traducional , Escarro/química , Adulto , Cobamidas/química , Cianetos/metabolismo , Fibrose Cística/diagnóstico , Fibrose Cística/microbiologia , Eletrodos , Feminino , Humanos , Ácido Hipocloroso/metabolismo , Cinética , Masculino , Pessoa de Meia-Idade , Oxirredução , Carbamilação de Proteínas , Pseudomonas aeruginosa/metabolismo , Escarro/microbiologia
20.
Talanta ; 178: 400-409, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29136840

RESUMO

We examined the feasibility of using handheld mid-infrared (MIR) Fourier-Transform infrared (FT-IR) instrumentation for detecting and analysing cyanide (CN) contamination in field contaminated soils. Cyanide spiking experiments were first carried out, in the laboratory, to test the sensitivity of infrared Fourier transform (DRIFT) spectrometry to ferro- and ferricyanide compounds across a range of reference soils and minerals. Both benchtop and handheld diffuse reflectance infrared spectrometers were tested. Excellent results were obtained for the reference soils and minerals, with the MIR outperforming the near-infrared (NIR) range. Spectral peaks characteristic of the -C≡N group were observed near 2062 and 2118cm-1 in the MIR region for the ferro- and ferricyanide compounds spiked into soils/minerals, respectively. In the NIR region such peaks were observed near 4134 and 4220cm-1. Cyanide-contaminated samples were then collected in the field and analyzed with the two spectrometers to further test the applicability of the DRIFT technique for soils containing aged CN residues. The prediction of total CN in dry and ground contaminated soils using the handheld MIR instrument resulted in a coefficient of determination (R2) of 0.88-0.98 and root mean square error of the cross-validation (RMSE) of 21-49mgkg-1 for a CN range of 0-611mgkg-1. A major peak was observed in the MIR at about 2092cm-1 which was attributed to "Prussian Blue" (Fe4[Fe(CN)6]3·xH2O). These results demonstrate the potential of handheld DRIFT instrumentation as a promising alternative to the standard laboratory method to predict CN concentrations in contaminated field soils.


Assuntos
Cianetos/análise , Poluentes do Solo/análise , Solo/química , Espectroscopia de Infravermelho com Transformada de Fourier/instrumentação , Cianetos/química , Ferricianetos/análise , Ferricianetos/química , Poluentes do Solo/química
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA