TOTAL AND SOLUBLE ALUMINUM IN SAMPLES OF COMMERCIAL MATE-HERB IN RIO GRANDE DO SUL STATE, BRAZIL

Abstract

The mate herb has economic and social importance in the state of Rio Grande do Sul, Brazil. The “chimarrão”, ground leaves infusion of herb mate in hot water, is a traditional habit of “gauchos” who consume large quantities of the product annually. The mate herb is usually grown in acid and poor in nutrients soils, which have varying levels of exchangeable aluminum. The mate herb is tolerant to aluminum, metal which is phytotoxic for most crops. The aluminum can be absorbed and accumulated in the human body and be toxic. The research aimed to quantify the level of aluminum in ten samples of commercial trademarks of mate herb. The samples were submitted to two methods of extraction: with nitropercloric acid, to determine the total content of the element in the samples (Al-total) and sequentially with hot water at 60 ^oC to determine the soluble fraction (Al-soluble). The levels of Al-total differed significantly among the samples, ranging from 256.85 to 715.52 mg kg^-1. The greatest levels of Al-total were determined in samples of the brand 3 (688.00 mg kg^-1) and of the brand 10 (715.52 mg kg^-1). The levels of Al-soluble also differed significantly in the samples, ranging from 0.00 to 56.74 mg dm^-3. The sample of the brand3, however, not presented the greatest level of Al-soluble, indicating that, possibly, the level of Al-soluble is related to ionic and organic forms of the element in the plant.