Abstract Mineral profiles of eleven fruits from the northeastern Brazilian agrobiodiversity have been determined. Samples of cajui, murici, pequi, jenipapo, mangaba, bacuri, caja, umbu-caja, umbu, pitanga and araça fruits were digested and element content determined by inductively coupled plasma optical emission spectrometry (ICP-OES). The accuracy of method was performed using SRM 2338 and all elements were statistically similar with 95% of confidence. Potassium is present in higher amounts in the edible part of the fruits, ranging from 107 to 402 mg 100 g-1, followed by P in the range 16 - 150 mg 100 g-1. Iron, presents the lowest content, ranges from 0.07 to 1.1 mg 100 g-1. Caja and umbu-caja fruits are noteworthy sources of P. Analysis of variance (ANOVA) and Principal Component Analysis were performed in order to check similarities between the fruit groups according to the trace element content. The data provide a source of information characterizing the Brazilian biodiversity and it may help the nutritional intake of these fruits in the region.

A method for determination of Cr(III) and Cr(VI) in cement and cement-related materials was studied. Molecular absorption spectrophotometry based on 1,5-diphenylcarbazide as chromogenic reagent was used for determination of Cr(VI) after alkaline extraction. The total chromium concentration was determined using flame atomic absorption spectrometry (FAAS) after complete sample decomposition by fusion. The quantification of Cr(III) was accomplished by subtracting the Cr(VI) concentration from the total chromium concentration. The concentration of Cr(III) in the samples ranged from 10.9 to 88.0 mg kg-1, whereas only in few samples the Cr(VI) concentration was higher than the value established by the European Community to this type of sample [2 mg kg-1 Cr(VI)].

Determination of Cr(VI) and Cr(III) was studied in soil samples accidentally contaminated with sulphochromic solution. Molecular absorption spectrophotometry based on the diphenylcarbazide method was used for the determination of Cr(VI) after its alkaline extraction. The total chromium concentration was determined using ICP OES. The quantification of Cr(III) was accomplished by subtracting the Cr(VI) concentration from the total chromium concentration. Regardless of the known contamination of the soil samples by sulphochromic solution, concentrations of Cr(VI) were below the detection limit. Addition and recovery experiments for Cr(VI) in soil samples with and without organic matter indicated its influence on the reduction of Cr(VI) to Cr(III).