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A method is presented for the determination of trace levels of fluoride in drinking water and sea water, based on the formation of aluminium monofluoride in an electrothermal graphite furnace, followed by molecular absorption at 227.45 nm. Two linear intervals extending over wide Fconcentration ranges (0-0.2 and 0.2-0.4" pg ml-1 for the peak-height relationship and 0-1 and 1-2 pg ml-1 for the peak-area relationship) were found.The proposed method was applied to natural and artificial drinking and sea waters from a variety of sources and with different saline contents. The detection limit was 8 ng ml-1 and the determination limit 20 ng ml-1. The peak-height precision at 0.2 and 0.4 pg ml-1 of Fwas 5% and 7%, respectively.Fcontents can be measured with a simple sample dilution. The use of a deuterium lamp allows simultaneous background correction. Interferences from cations, acidic media and anions were investigated.

A simple, rapid and accurate method for the direct determination of Ca and the indirect determination of Mg in milk and yogurt by complexometric titration is proposed. The titration is based on the precipitation of proteins by salicylic acid followed by titration using a complexometric indicator. Palladiazo can be used as the indicator for the determination of Ca and Mg. The complexometric indicators Eriochrome Black T, Murexide and Calcein can also be used after treating milk with salicylic acid.

The ABR thresholds were significantly elevated in animals from all groups after cisplatin treatment. A maximum accumulation of Pt for inner ear and brain was revealed around the first week: 3.175 (57%) and 0.342 (72%), respectively. Pt significantly accumulated in greater quantities in ear than in brain (p<0.01) and was cleared at a higher rate in brain than in ear (p<0.01) following cochlea/brain ratio analysis. No statistically significant correlation was found between amounts of Pt and hearing loss in the study animals.

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