RESUMO
In the present study, we investigated the influence of diazepam (DZP) on the excretion of TOL by examining their urinary metabolites, hippuric acid (HA) and ortho-cresol (o-C). Male Wistar rats were exposed to TOL (20ppm) in a nose-only exposure chamber (6h/day, 5days/week for 6 weeks) with simultaneous administration of DZP (10mg/kg/day). Urinary o-C levels were determined by GC-MS, while HA, creatinine (CR), DZP and its metabolite, nordiazepam, were analysed by HPLC-DAD. The results of a Mann-Whitney U test showed that DZP influenced the urinary excretion of o-C (p<0.05). This pioneering study revealed that there was an interaction between DZP and TOL, probably by the inhibition of the CYP isoforms (CYP2B6, CYP2C8, CYP2E1, and CYP1A2) involved in the oxidative metabolism of the solvent. This is relevant information to be considered in the biomonitoring of occupational toluene exposure.
Assuntos
Poluentes Ocupacionais do Ar/urina , Cresóis/urina , Diazepam/farmacologia , Exposição por Inalação/análise , Exposição Ocupacional/análise , Tolueno/urina , Poluentes Ocupacionais do Ar/metabolismo , Animais , Biomarcadores/urina , Sistema Enzimático do Citocromo P-450/metabolismo , Diazepam/administração & dosagem , Interações Medicamentosas , Isoenzimas , Masculino , Ratos Wistar , Tolueno/metabolismoRESUMO
Prenatal exposure to bisphenol A (BPA) may be associated with adverse health effects in the developing fetus; however, little is known about predictors of BPA exposure during pregnancy. We examined BPA exposure in 491 pregnant women from the Center for the Health Assessment of Mothers and Children of Salinas (CHAMACOS) cohort and explored the role of living in the United States on significant dietary predictors of BPA exposure. Women provided urine samples up to two times during pregnancy (n=866 total samples). We computed the intraclass correlation coefficient (ICC) to evaluate variability in concentrations between collections and used generalized estimating equation (GEE) models to assess predictors of exposure. Geometric mean (GSD) BPA concentrations were 0.9 (2.8)µg/L and 1.0 (2.6)µg/L at the first and second prenatal visits, respectively. We observed greater within- than between-woman variability in urinary BPA concentrations (ICC=0.22). GEE models suggest that women who lived in the United States their entire life had 38% (CI: -0.1, 89.3) higher urinary BPA concentrations compared with other immigrant women. Additionally, women who consumed ≥3 sodas per day or hamburgers three times a week or more had 58% (CI: 18.0, 112.1) and 20% (CI: -0.2, 45.2) higher urinary BPA concentrations, respectively, compared with women who consumed no sodas or hamburgers. A higher percentage of women who lived their entire life in the United States reported increased consumption of sodas and hamburgers compared with other immigrant women. Independent of other factors, BPA urinary concentrations were slightly higher when the sample was collected later in the day. As in previous studies, high within-woman variability in urinary BPA concentrations confirms that several samples are needed to properly characterize exposure during pregnancy. Results also suggest that some factors could be modified to minimize exposures during pregnancy in our study participants (e.g., reducing soda and hamburger intake) and that factors associated with acculturation might increase BPA concentrations.
Assuntos
Poluentes Ocupacionais do Ar/urina , Compostos Benzidrílicos/urina , Exposição Materna , Fenóis/urina , Adulto , California , Dieta/efeitos adversos , Emigrantes e Imigrantes , Feminino , Humanos , México/etnologia , Gravidez , Adulto JovemRESUMO
A pilot cross-sectional study was carried out in a group of 39 male brick manufacturers in San Luis Potosi, Mexico to identify epigenetic biomarkers of exposure to polycyclic aromatic hydrocarbons (PAHs). A questionnaire was used to compile the smoking and drinking habits, clinical history, working time, and socioeconomic characteristics of the participants. 1-Hydroxypyrene (1-OHP) levels were measured from urine samples using high-performance liquid chromatography, and genomic DNA was isolated from blood samples for methylation analysis using pyrosequencing. The mean 1-OHP level was 0.18 µg g(-1) creatinine (range 0.023-1.11), which was below the expected occupational exposure level. After adjusting for potential confounders, the 1-OHP urine concentration was negatively associated with DNA methylation of the interleukin 12 (ß=-1.57; 95% CI: -2.9 to -0.23; p=0.02) and p53 gene promoters (ß=-2.7; 95% CI: -5.46-0.06; p=0.055). Suggestive negative associations were also found for the TNF-α gene (ß=-3.9; 95% CI:-8.28-0.48; p=0.08) and Alu sequences (ß=-0.55; 95% CI:-1.25-0.16; p=0.12). Although the individual exposures to PAHs as estimated by urinary 1-OHP concentrations were low, changes in specific and global DNA methylation were observed.
Assuntos
Poluentes Ocupacionais do Ar/análise , Exposição Ocupacional/estatística & dados numéricos , Hidrocarbonetos Policíclicos Aromáticos/análise , Adolescente , Adulto , Idoso , Poluentes Ocupacionais do Ar/toxicidade , Poluentes Ocupacionais do Ar/urina , Biomarcadores/urina , Epigênese Genética/efeitos dos fármacos , Humanos , Masculino , México , Pessoa de Meia-Idade , Exposição Ocupacional/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/urina , Adulto JovemRESUMO
OBJECTIVE: Quantifying polycyclic aromatic hydrocarbon levels in urine samples taken from a population of traffic police working in the metropolitan area of Bogotá who were occupationally exposed to 1-hydroxypyrene (1-OHP) and 3-hydroxy-benzo[a]pyrene (3-BaP) metabolites from polycyclic aromatic hydrocarbons (PAH) having toxicological interest, related to their detection, and a degree of exposure to particulate material having a size less than 10 micrometres (PM10) and/or other factors. METHODS: A cross-sectional study was made of 524 traffic police, 413 of whom were engaged in operational and 111 in administrative functions. Urine samples were taken from all the individuals included in the study for determining PAH metabolites by gas chromatography/mass spectrometry (GC/MS). The presence of factors associated with the detection of metabolites was analysed, such as smoking, consuming roasted/grilled food, place of residence and exposure to PM10. The odds ratio (OR) was calculated as a measure of association. RESULTS: Higher 1-OHP and 3-BaP levels were found in exposed individuals, having a significant OR for detecting 6.3 ((3.6-11.1) 95 % CI) and 15.6 ((6.2-39) 95 % CI) metabolites, respectively. Significant OR were found for detecting PAH metabolites and exposure to PM10, smoking and consuming roasted/grilled food. DISCUSSION: There was an important and significant association between work-related exposure to environmental contamination and detecting toxicologically important PAH metabolites in urine samples. Factors such as smoking, consuming freshly grilled/roasted food and exposure to PM10 were also found to be positively associated with detecting such metabolites, but to a lesser extent.
Assuntos
Poluentes Ocupacionais do Ar/urina , Exposição Ocupacional/efeitos adversos , Polícia , Hidrocarbonetos Policíclicos Aromáticos/urina , Colômbia , Estudos Transversais , Humanos , Saúde da População UrbanaRESUMO
Paints are composed of an extensive variety of hazardous substances, such as organic solvents and heavy metals. Biomonitoring is an essential tool for assessing the risk to occupational health. Thus, this study analyzed the levels of biomarkers of exposure for toluene, xylene, styrene, ethylbenzene, and lead, as well as the oxidative stress biomarker alterations in painters of an industry. Lipid peroxidation biomarker (MDA), delta-aminolevulinate dehydratase (ALA-D), nonprotein thyol groups, superoxide dismutase and catalase (CAT) were analyzed in exposed and nonexposed subjects. We estimated which of the paint constituents have the greatest influence on the changes in the biomarkers of oxidative stress in this case of co-exposure. The results demonstrated that despite the fact that all the biomarkers of exposure were below the biological exposure limits, the MDA levels and antioxidant enzyme activities were increased, while nonprotein thyol groups and ALA-D levels were decreased in painters when compared with nonexposed subjects. After statistic test, toluene could be suggested as the principal factor responsible for increased lipid peroxidation and inhibition of ALA-D enzyme; however, further studies on the inhibition of ALA-D enzyme by toluene are necessary.
Assuntos
Exposição Ocupacional/análise , Estresse Oxidativo/efeitos dos fármacos , Pintura/toxicidade , Xenobióticos/toxicidade , Adulto , Poluentes Ocupacionais do Ar/toxicidade , Poluentes Ocupacionais do Ar/urina , Derivados de Benzeno/toxicidade , Derivados de Benzeno/urina , Biomarcadores/sangue , Biomarcadores/urina , Catalase/sangue , Creatina/urina , Humanos , Chumbo/toxicidade , Chumbo/urina , Peroxidação de Lipídeos/efeitos dos fármacos , Saúde Ocupacional , Sintase do Porfobilinogênio/sangue , Medição de Risco , Estireno/toxicidade , Estireno/urina , Superóxido Dismutase/sangue , Tolueno/toxicidade , Tolueno/urina , Xenobióticos/urina , Xilenos/toxicidade , Xilenos/urinaRESUMO
OBJECTIVE: To evaluate whether there are visual and neuropsychological decrements in workers with low exposure to Hg vapor. METHODS: Visual fields, contrast sensitivity, color vision, and neuropsychological functions were measured in 10 workers (32.5 +/- 8.5 years) chronically exposed to Hg vapor (4.3 +/- 2.8 years; urinary Hg concentration 22.3 +/- 9.3 microg/g creatinine). RESULTS: For the worst eyes, we found altered visual field thresholds, lower contrast sensitivity, and color discrimination compared with controls (P <0.05). There were no significant differences between Hg-exposed subjects and controls on neuropsychological tests. Nevertheless, duration of exposure was statistically correlated to verbal memory and depression scores. CONCLUSIONS: Chronic exposure to Hg vapor at currently accepted safety levels was found to be associated with visual losses but not with neuropsychological dysfunctions in the sample of workers studied.
Assuntos
Poluentes Ocupacionais do Ar/efeitos adversos , Transtornos Mentais/induzido quimicamente , Transtornos Mentais/epidemiologia , Exposição Ocupacional/efeitos adversos , Transtornos da Visão/induzido quimicamente , Transtornos da Visão/epidemiologia , Adulto , Poluentes Ocupacionais do Ar/urina , Brasil/epidemiologia , Percepção de Cores/efeitos dos fármacos , Testes de Percepção de Cores , Sensibilidades de Contraste/efeitos dos fármacos , Creatinina/urina , Feminino , Humanos , Masculino , Mercúrio/urina , Pessoa de Meia-Idade , Testes Neuropsicológicos , Exposição Ocupacional/análise , Campos Visuais/efeitos dos fármacos , Adulto JovemRESUMO
OBJECTIVE: Paraquat is an herbicide widely used worldwide. This study determined the extent of occupational exposure to paraquat among farm workers in Costa Rica and identified determinants of occupational exposure. METHODS: Twenty-four hour urine samples were collected from 119 paraquat handlers and 54 non-handlers from banana, coffee and palm oil farms. Information about herbicide handling operations was also collected. The urinary paraquat levels were determined by an enzyme-linked immunosorbent assay (ELISA) with a limit of quantification (LOQ) of 2 ng/mL. Inhalable dust and airborne paraquat levels were simultaneously measured for a subset of the participants. RESULTS: Urinary paraquat measurements were non-detectable or very low when workers did not handle paraquat. For handlers, 83.3, 47.1 and 63.9% of the samples were below the LOQ on before-, during- and after-paraquat spray days, respectively. The arithmetic mean (+/-SD) of urinary paraquat level on days when workers handled paraquat was 6.3 (+/-10.45) microg/24 h. Paraquat exposures among handlers on spray day were significantly associated with the type of crop. CONCLUSION: Non-handlers had negligible urinary paraquat, while detectable paraquat exposures were observed among handlers on spray day. Urinary paraquat levels were different by crop.
Assuntos
Herbicidas/urina , Exposição Ocupacional/análise , Paraquat/urina , Adulto , Agricultura , Poluentes Ocupacionais do Ar/urina , Café , Costa Rica , Monitoramento Ambiental , Ensaio de Imunoadsorção Enzimática , Humanos , Inalação , Masculino , Pessoa de Meia-Idade , Roupa de Proteção , Análise de Regressão , Inquéritos e QuestionáriosRESUMO
People in developing countries are often considered at greater risk of mercury (Hg) poisoning due to a variety of factors including a lack of awareness regarding their occupational risks. Individuals requiring urine mercury (U-Hg) analysis at the Center for Toxicological Investigations of the University of Carabobo (CITUC), between 1998 and 2002 were studied to identify demographic characteristics associated to U-Hg levels. The studied population included individuals with a history of exposure (or related exposures) to Hg processes, and was comprised of 1159 individuals (65 children, 1094 adults) ages 0.58-79 years old, mean 36.63+/-12.4. Children's geometric mean U-Hg levels were 2.73 microg/g Creatinine (Ct) and in adults 2.55 microg/g Ct. The highest frequency of adults' occupations were shipyard workers (35.47%), dentists (23.5%), lab technicians (11.43%), dental employees 10.42% and miners (10.2%). Chemical laboratory technicians had the highest mean U-Hg (4.46 microg/g Ct). Mean U-Hg levels in female adults (3.45 microg/g Ct) were statistically superior to levels in male adults (2.15 microg/g Ct). Two of the 172 women in reproductive age, had U-Hg levels higher than 78 microg/g Ct. Individuals from Falcon State were found to have the highest mean U-Hg (4.53 microg/g Ct). U-Hg levels higher than permissible limits were found in only 2 states (Carabobo and Bolivar) with a total of 24 cases. Although the results of this investigation were highly variable, the findings can be used to examine circumstances which influence mercury toxicity trends, and possibly used in future studies working to identify Hg exposures.
Assuntos
Poluentes Ocupacionais do Ar/sangue , Poluentes Ocupacionais do Ar/urina , Mercúrio/sangue , Mercúrio/urina , Exposição Ocupacional , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Odontologia , Monitoramento Ambiental , Feminino , Ouro , Humanos , Lactente , Masculino , Pessoal de Laboratório Médico , Pessoa de Meia-Idade , Mineração , Navios , VenezuelaRESUMO
There are many studies documenting the genotoxic effects of environmental exposure to arsenic. Nevertheless, few data are available on the genotoxic risks of occupational arsenic exposure. In the present study, we have evaluated whether or not occupational exposure to arsenic in a copper smelting plant results in a significant increase in the frequency of sister chromatid exchange (SCE). SCE frequencies, proliferation rate index (PRI), and high frequency cells (HFCs) were evaluated in peripheral blood lymphocytes from a group of 105 arsenic-exposed workers from a Chilean smelting plant (exposed group). Similar assays were conducted on a group of 55 workers employed at the same mine but involved in administrative jobs (internal control), and on 48 workers of another mine, with no significant levels of arsenic (external control). Small but significant increases in SCE frequency were observed in the arsenic-exposed workers compared with the external control group (6.28+/-0.09 vs. 5.84+/-0.14 SCE/cell; P<0.01). Also, significantly higher frequencies of HFCs were observed in the exposed group (2.21%+/-0.20%) than in either the external control group (1.20+/-0.23; P=0.002) or the internal control group (1.30+/-0.24; P=0.008). However, there was no relationship between arsenic levels in the urine of the subjects and SCE or HFC frequency. The results of the study indicate that copper smelting results in slightly increased levels of DNA damage. However, our data were not consistent with arsenic exposure being the cause of the increase.
Assuntos
Poluentes Ocupacionais do Ar/urina , Arsênio/urina , Exposição Ocupacional , Troca de Cromátide Irmã , Adulto , Poluentes Ocupacionais do Ar/toxicidade , Arsênio/toxicidade , Chile , Cobre , Monitoramento Ambiental , Humanos , Linfócitos/efeitos dos fármacos , Metalurgia , Pessoa de Meia-IdadeRESUMO
Organophosphorous pesticides (OPs) are suspected of altering reproductive function by reducing brain acetylcholinesterase activity and monoamine levels, thus impairing hypothalamic and/or pituitary endocrine functions and gonadal processes. Our objective was to evaluate in a longitudinal study the association between OP exposure and serum levels of pituitary and sex hormones. Urinary OP metabolite levels were measured by gas-liquid chromatography, and serum pituitary and sex hormone levels by enzymatic immunoassay and radioimmunoassay in 64 men. A total of 147 urine and blood samples were analyzed for each parameter. More than 80% of the participants had at least one OP metabolite in their urine samples. The most frequent metabolite found was diethylthiophosphate (DETP; 55%), followed by diethylphosphate (DEP; 46%), dimethylthiophosphate (DMTP; 32%), and dimethyldithiophosphate (DMDTP; 31%). However, the metabolites detected at higher concentrations were DMTP, DEP, DMDTP, and dimethylphosphate. There was a high proportion of individuals with follicle-stimulating hormone (FSH) concentrations outside the range of normality (48%). The average FSH serum levels were higher during the heavy pesticide spraying season. However, a multivariate analysis of data collected in all periods showed that serum FSH levels were negatively associated with urinary concentrations of both DMTP and DMDTP, whereas luteinizing hormone (LH) was negatively associated with DMTP. We observed no significant associations between estradiol or testosterone serum levels with OP metabolites. The hormonal disruption in agricultural workers presented here, together with results from experimental animal studies, suggests that OP exposure disrupts the hypothalamic-pituitary endocrine function and also indicates that FSH and LH are the hormones most affected.