Increased serum bile acids as a possible biomarker of hepatotoxicity in Brazilian workers exposed to solvents in car repainting shops.

The objective was to evaluate total serum bile acids (SBA) as a biological marker of hepatotoxicity in car painters exposed to organic solvents and to compare their performance with classic biochemical parameters of liver function. SBA were analysed in a selected group of workers (n=57) occupationally exposed to a mixture of organic solvents and in a control group (n=51). In addition, aspartate aminotransferase (AST), alanine aminotransferase (ALT), total bilirubin (TB), gamma-glutamyltransferase (GGT) and alkaline phosphatase (ALP) were determined in the two groups. Urinary hippuric acid was measured in all samples. Statistical analysis of the data revealed a significant increase in the concentration of SBA, AST, ALP and TB in exposed workers compared with controls (Mann-Whitney, p

Occurrence of aflatoxins B1, B2, G1 and G2 in some Brazilian pet foods.

The presence of cereals and grains in the formulation of pet foods suggests the need to control aflatoxin contamination in these foods. The objective of the study was to analyse domestic pet food to determine the occurrence of aflatoxins as well as their risk to animal health. One hundred food samples (45 for dogs, 25 for cats, 30 for birds) were collected at random from pet shops in Alfenas city, south-east Brazil. Thin-layer chromatography was used for separation, identification and quantification of the compounds after validation of the method. Aflatoxins were detected in 12.0% of the samples. Levels of aflatoxins (B(1) + B(2) + G(1) + G(2)) above the maximum limit established in Brazil (50 microg kg(-1)) for animal food were detected in five of the 12 positive samples (41.7%). The concentration of total aflatoxins was 15-374 microg kg(-1) (mean 131 microg kg(-1)). All samples containing peanuts were positive for aflatoxin B(1). Aflatoxins are carcinogenic and their consumption might be a risk for domestic animal health. The high prevalence of aflatoxin B(1) in foods prepared for birds, species highly susceptible to aflatoxins, shows the need for the re-evaluation of the use of peanuts (present in seven of the eight samples positives for aflatoxin) and/or the addition of fungicides to the food.

[Nitrates and nitrites in homemade and industrial cheeses commercialized in the Southern region of Minas Gerais, Brazil]. / Nitratos e nitritos em queijos caseiros e industrializados comercializados na região sul de Minas Gerais, Brasil.

The evaluation of nitrate and nitrite in homemade and industrialized cheeses commercialized in the southern region of Minas Gerais State, was the aim of this work. In Brazil, the use of these additives is permitted at maximum levels of 50 mg/kg. The basis of the previously validated method is the quantitative reduction of nitrate to nitrite through cadmium column and spectrophotometric determination after nitrite diazotation with sulphanilic acid/alpha-naphtol reagent. From all samples analyzed, 38 (88.37%) showed neither a nitrate nor nitrite detectable content; 5 samples (11.63%) presented nitrate, 4 of them being above the tolerated level and only one (2.33%) showed detectable nitrite, however below the permissible limit. The majority of samples did not show nitrate or nitrite at detectable levels. However, though probably safe from a toxicological point of view, the results can implicate an increased risk of bacteriological contamination.

Urinary nickel as bioindicator of workers' Ni exposure in a galvanizing plant in Brazil.

OBJECTIVES: We measured urinary nickel (U-Ni) in ten workers (97 samples) from a galvanizing plant that uses nickel sulfate, and in ten control subjects (55 samples) to examine the association between occupational exposure to airborne Ni and Ni absorption. METHODS: Samples from the exposed group were taken before and after the work shift on 5 successive workdays. At the same time airborne Ni (A-Ni) was measured using personal samplers. Ni levels in biological material and in the airborne were determined by a graphite furnace atomic absorption spectrometry validated method. In the control group the urine samples were collected twice a day, in the before and after the work shift, on 3 successive days. RESULTS: Ni exposure low to moderate was detected in all the examined places in the plant, the airborne levels varying between 2.8 and 116.7 micrograms/m3 and the urine levels, from samples taken postshift, between 4.5 and 43.2 micrograms/g creatinine (mean 14.7 micrograms/g creatinine). Significant differences in U-Ni creatinine were seen between the exposed and control groups (Student's t test, P < or = 0.01). A significant correlation between U-Ni and A-Ni (r = 0.96; P < or = 0.001) was detected. No statistical difference was observed in U-Ni collected from exposed workers in the 5 successive days, but significant difference was observed between pre- and postshift samples. CONCLUSIONS: Urinary nickel may be used as a reliable internal dose bioindicator in biological monitoring of workers exposed to Ni sulfate in galvanizing plants regardless of the day of the workweek on which the samples are collected.

Derivatization methodology for the analysis of butorphanol by gas chromatography-mass spectrometry.

Butorphanol is an opioid used as analgesic in humans and other species. In horses, it can cause locomotor stimulation at low doses. This drug is not well chromatographed by GC and so, it is necessary to transform it into a more suitable compound, which can be done by derivatization. The derivatization of a drug is used to impart volatility, masking polar groups to improve the results in gas chromatographic analysis. We have evaluated N,O-bis(trimethylsilyl)- trifluoracetamide (BSTFA)+ 1% trimethylchlorsilane (TMCS) and N-methyl-N-trimethylsilil-trifluoroacetamide (MSTFA) as derivatizing reagents for butorphanol at 30, 60 and 80 degrees C during 15, 30 and 60 min. The effects of dilution of these reagents with toluene and the evaporation before the derivatization were tested. Both reagents can be used for butorphanol derivatization and analysis and the dilution and evaporation steps did not alter the final results. The best derivatization conditions were 15 min at 80 degrees C, although 60 degrees C, although 60 degrees C during 60 min were also suitable.

[Reference values for carboxyhemoglobin]. / Valores de referência para carboxiemoglobina.

INTRODUCTION: The reference values (RV) of biological indicators are used in the interpretation of the results of such indicators in individuals occupationally exposed to chemical agents. The Brazilian Group for the Establishment of Reference Values has worked on these definitions for the purpose of establishing RVs for several bioindicators in various regions of the country. In the present study, the RV for carboxyhemoglobin (COHb) was determined for the South of Minas Gerais. MATERIAL AND METHOD: The COHb was analyzed by the Beutler and West (1984) spectrophotometric method, optimized in our laboratory. In all the samples, analyses of some biochemical and hematological parameters were made to evaluate the health condition of a population of 200 volunteer non-smokers occupationally not exposed to CO. Each individual answered a questionnaire to obtain data pertinent to the interpretation of the results. The reference values were expressed as mean values +/- standard deviation, with a 95% confidence interval, and an upper reference value. The statistical distribution of the results was made so as to enable comparisons between the results of groups of workers, rather than individual evaluations, to be made. RESULTS AND CONCLUSIONS: The mean value +/- standard deviation was 1.0% +/- 0.75; the 95% confidence interval was 0.9-1.1% and the upper reference value was 2.5%. By the t Student test (p < or = 0.05), no difference was detected between the values related to sex, age or ingestion of alcoholic beverages. The reference values obtained were close to those reported for others countries.

[Glue solvents: abuse and adverse effects on health]. / Solventes de cola: abuso e efeitos nocivos à saúde.

In Brazil, glue sniffing has been of growing concern due to the increasing number of abusers, most of them children and teen-agers of low socio-economic level. This review article presents some aspects of this kind of abuse, with special emphasis on the deleterious effects of acute and/or chronic solvent inhalation (glue-sniffing).