Leiliane Coelho André

Analysis of plasticiser migration to meat roasted in plastic bags by SPME–GC/MS

Plasticisers are compounds used in the polymer industry to increase the flexibility of plastics. Some of these compounds cause endocrine dysfunction in humans and animals by interfering with the production, release, transport, metabolism, binding or elimination of natural hormones in the body and are therefore recognised as endocrine disruptors. This paper describes cold-fibre solid-phase microextraction as a sampling technique to analyse eight plasticisers in spices and roasted chicken meat stored in plastic bags by gas chromatography-mass spectrometry. Limits of detection for this method ranged from 0.01 to 0.18 μg kg(-)(1). Diisobutyl phthalate and dibutyl phthalate were found in the samples of spices and roasted chicken meat. The highest concentrations of plasticisers were found in the spices used to cook the chicken meat.

Analysis of Phthalate Migration to Food Simulants in Plastic Containers during Microwave Operations

Phthalates used as plasticizers in the manufacture of household containers can potentially be transferred to foods that are stored or heated in these plastic containers. Phthalates are endocrine disruptor compounds (EDC) and are found in very low concentrations in foods, thus, highly sensitive analytical techniques are required for their quantification. This study describes the application of a new method developed for analyzing the migration of dibutylphthalate (DBP) and benzylbutylphthalate (BBP) from plastic food containers into liquid food simulants. This new method employs the technique of solid phase microextraction cooled with liquid nitrogen. The analysis was conducted by gas chromatography/mass spectrometry (GC/MS) using a polyacrylate fiber. Ultrapure water was used as a simulant for liquids foods, and both new and used plastic containers were placed in a domestic microwave oven for different periods of time at different power levels. The limits of detection for DBP and BBP were 0.08 µg/L and 0.31 µg/L, respectively. BBP was not found in the samples that were analyzed. DBP was found in concentrations ranging from <LOQ to 7.5 µg/L. In general, an increase in migration was observed in containers that were used for a prolonged time, which correlated with increasing heating time.

Quantitative Analysis of Endocrine Disruptors by Comprehensive Two-Dimensional Gas Chromatography

Comprehensive two-dimensional gas chromatography has been successfully applied to the analysis of various organic contaminants; however, few studies report its use in the analysis of endocrine disrupting compounds. These compounds are suspected to cause dysfunction of the endocrine system in humans and animals. This work describes the development of a method to analyse dibutylphthalate, benzylbutylphthalate, nonylphenol and octylphenol in water using solid-phase microextraction (SPME) and comprehensive two-dimensional gas chromatography with a flame ionisation detector. The merit parameters of the comprehensive two-dimensional gas chromatography with flame ionisation detector method were weighed against a gas chromatography/mass spectrometry-single ion monitoring method of endocrine disrupting compounds analysis. The compounds were evaluated over a concentration range of 0.2 to 6.0 µg L-1 . The use of a two-dimensional chromatography method proved to be advantageous in analysing endocrine disrupting compounds, according to the observed increase of the signal relative to the noise and peak resolution.

Normas ocupacionais do benzeno: uma abordagem sobre o risco e exposição nos postos de revenda de combustíveis

Introduction: workers are subject to risks from environmental and occupational exposure to benzene. This situation is even more critical when combined with social inequality, multiple exposure, individual susceptibility, environmental degradation, and possible interactions between environmental contaminants. In addition, regulations are not always established and/or updated only from scientific evidences, because they are processes permeated by conflicts of interest. Objective: to produce a critical analysis on risk identification and benzene exposure evaluation. Methods: literature and documentary review of the Brazilian and international regulatory standards on benzene exposure, toxicological aspects, occupational and environmental exposure, and risk evaluation. Discussion: benzene exposure control permeates the technical-political dispute of health and safety, resulting in a regulatory standard from consensus of understandings. These understandings are shaped by the dispute between health protection and business management of working conditions, to the detriment of scientific evidence. In this context, the Occupational Exposure Limits can vary significantly between countries and agencies, despite the universal recognition that there are no safe limits for benzene exposure, because it is a carcinogenic compound.

Estratégias analíticas com cromatografia e espectrometria de massas para biomonitorização da exposição ao benzeno pela determinação do ácido S-fenilmercaptúrico urinário

Introduction: benzene is a substance of recognized toxicity and its biomonitoring of exposure becomes critical for preventing health damages, especially in occupational exposure situations. Among all the biomarkers of exposure, S-phenylmercapturic acid is considered the only specific one, but due to its low concentrations in urine, acute analytical techniques capable of quantifying traces must be used. Objective: to review methodologies based on chromatography and mass spectrometry for determination of S-phenylmercapturic acid. Method: literature review on the determination of urinary S-phenylmercapturic acid by chromatographic techniques and mass spectrometry in the main scientific databases, considering the period between 1951 and 2015. Results: 120 documents served as theoretical basis for the construction of this review. The analytical technique that was most applied was the coupling of liquid chromatography with mass spectrometry. However, the methods differ according to the preparation of samples. Conclusion: the high cost of equipment acquisition and maintenance are limiting factors for the diffusion of chromatography systems and mass spectrometry. Nevertheless, its high sensitivity and selectivity enable these coupled techniques to elucidate situations of occupational and environmental exposure to pollutants, such as benzene.

Utilização de biomarcadores de genotoxicidade e expressão gênica na avaliação de trabalhadores de postos de combustíveis expostos a vapores de gasolina

Introduction: an exposure evaluation measures its intensity, frequencyand duration, detecting premature damage that, if ignored, might develop into a harmful framework. On environmental and occupational health fields, genotoxicity biomarkers have been widely used for this evaluation. Objective: to identify, describe and discuss main genotoxicity biomarkers and their use together with gene expression evaluation techniques in studies concerning occupational exposure to benzene in gas stations (GS). Methods: bibliographical review of studies published between 1995 and 2015. Results: the following techniques were identified: comet assay, oxidative stress, micronuclei, chromosomal aberrations, polymorphisms, DNA and protein adducts, epigenetic factors and gene expression. We observed that genetic and epigenetic damage tests are used in gas station attendants who participate in worker’s health programs or in researches, although a short number of publications on the theme have been identified. This can be explained by the small number of countries where such job still exists and by the limitations for developing research in such countries. Conclusion: genotoxicity biomarkers and gene expression techniques are useful for detecting the premature damage resulting from this occupational exposure and must be jointly evaluated.

An efficient analytical method for determination of S-phenylmercapturic acid in urine by HPLC fluorimetric detector to assessing benzene exposure

Benzene is an important occupational and environmental contaminant, naturally present in petroleum and as by-product in the steel industry. Toxicological studies showed pronounced myelotoxic action, causing leukemic and others blood cells disorders. Assessing of benzene exposure is performed by biomarkers as trans, trans-muconic acid (AttM) and S-phenylmercapturic acid (S-PMA) in urine. Due to specificity of S-PMA, this biomarker has been proposed to asses lower levels of benzene in air. The aim of this study was to validate an analytical method for the quantification of S-PMA by High-Performance Liquid Chromatography with fluorometric detector. The development of an analytical method of S-PMA in urine was carried out by solid phase extraction (SPE) using C-18 phase. The eluated were submitted to water bath at 75°C and nitrogen to analyte concentration, followed by alkaline hydrolysis and derivatization with monobromobimane. The chromatography conditions were reverse phase C-18 column (240mm, 4mm and 5μm) at 35°C; acetonitrile and 0.5% acetic acid (50:50) as mobile phase with a flow of 0.8mL/min. The limits of detection and quantification were 0.22μg/L and 0.68μg/L, respectively. The linearity was verified by simple linear regression, and the method exhibited good linearity in the range of 10-100μg/L. There was no matrix effect for S-PMA using concentrations of 40, 60, 80 and 100μg/L. The intra- and interassay precision showed coefficient of variation of less than 10% and the recovery ranged from 83.4 to 102.8% with an average of 94.4%. The stability of S-PMA in urine stored at -20°C was of seven weeks. The conclusion is that this method presents satisfactory results per their figures of merit. This proposed method for determining urinary S-PMA showed adequate sensitivity for assessment of occupational and environmental exposure to benzene using S-PMA as biomarker of exposure.

Assessment of volatile organic compounds from banana Terra subjected to different alcoholic fermentation processes

Banana characteristics could provide yeast growth and support the action of yeast to produce beverages. The effects of enzymatic treatment, centrifugation, commercial yeast and two selected strains of Saccharomyces cerevisiae were investigated using the fermented banana Terra. Volatile organic compounds (VOCs) were determined by solid phase microextraction using gas chromatography mass spectrometry. The results showed that the condition employing enzymatic treatment, centrifugation and wet commercial yeast provided maximum ethanol yield (86%) and effiency (98%). Twenty-two compounds of distinct chemical classes were analysed including alcohols, esters, acids and aldehydes. The concentrations of the VOCs differed depending on the fermentation condition and were more influenced by using different yeasts. The limits of detection and quantification ranged from 0.056 to 2.694 mg L–1 and 0.057 to 2.904 mg L–1 respectively. Among the most prevalent VOCs the higher alcohols ranged from 353 to 1017 mg per 100 mL of anhydrous alcohol. The fermented banana studied showed a composition similar to other fermented fruit pulps.

Avaliação da exposição ocupacional ao benzeno em trabalhadores frentistas e analistas de combustíveis utilizando o Teste Cometa como biomarcador de genotoxicidade

Introducao: frentistas e analistas de combustiveis estao expostos a varios compostos orgânicos volateis presentes na gasolina, incluindo benzeno, que se destaca por sua importância toxicologica. Objetivo: avaliar a exposicao ocupacional ao benzeno na gasolina, utilizando o Teste Cometa como biomarcador de genotoxicidade em comparacao ao acido trans,trans-muconico urinario (AttM) como biomarcador de exposicao ao benzeno. Metodos: estudo de corte transversal com analises de biomarcadores de exposicao e de genotoxicidade em grupo de expostos ocupacionalmente ao benzeno atraves da gasolina e grupo controle. Resultados: o Teste Cometa mostrou uma media (desvio padrao) de indice de dano, expresso em unidades arbitrarias, no grupo exposto de 28,4 (10,1) significativamente mais elevado do que no grupo nao-exposto, 18,4 (10,1). O AttM urinario, em mg/g de creatinina, foi significativamente maior no grupo exposto, 1,13 (0,45), em relacao ao grupo nao exposto, 0,44 (0,33). Os dois biomarcadores apresentaram boa correlacao linear (r=0,81; p<0,05), indicando uma forte associacao entre o biomarcador de exposicao e o biomarcador de efeito. Conclusao: os resultados sugerem que uma maior exposicao ocupacional ao benzeno esta associada a um risco aumentado de dano genotoxico entre individuos expostos a gasolina.

Improved Method to Assess Polycyclic Aromatic Hydrocarbons in Atmospheric Gas Particles in Belo Horizonte, Brazil

ABSTRACT This article describes the development and validation of a solid-phase microextraction method using direct immersion and cold fiber (DI-CF-SPME) to collect samples in ambient air particulate matter and a gas phase to analyze 16 priority polycyclic aromatic hydrocarbons by gas chromatography mass spectrometry. This method has proven to yield good results for some validation parameters. Limits of detection and quantification ranged from 0.008 ng m−3 to 0.095 ng m−3 and from 0.020 ng m−3 to 0.101 ng m−3, respectively. The inter-assay precision shows a coefficient of variation ranging from 1.01% to 15.75%. The method was applied to the analysis of samples collected in 2014 and 2015 in the urban area of Belo Horizonte, located in southeastern Brazil. The samples were collected next to high-traffic routes and industrial regions using a PM10 (<10 μm) high-volume air sampler for 24-h periods. The total concentration of polycyclic aromatic hydrocarbon found in samples collected simultaneously in filter and foam were 8.53 ng m−3 and 18.58 ng m−3, respectively. Anthracene and fluoranthene showed the highest concentrations in the gas phase, whereas benzo(b)fluoranthene and benzo(ghi)perylene showed the highest levels in the particulate phase. A model based on principal component analysis was applied to identify possible anthropogenic sources of individual polycyclic aromatic hydrocarbons in 68 particulate matter samples. The results suggest that the main sources of these pollutants came from a combustion engine.