Studies on the acute biochemical effects of La(NO3)3 using 1H NMR spectroscopy of urine combined with pattern recognition

1H NMR spectroscopic and pattern recognition-based methods were applied to the studies on the acute biochemical effects of La(NO3)3. Male Wistar rats were separated into groups (n = 10) and each was treated with one of following compounds, sodium chromate (NaCrO4), mercury II chloride (HgCl2), 2-bromoethanamine hydrobromide (BEA), carbon tetrachloride (CCl4), hydrazine (HYD), α-naphthylisothiocyanate (ANIT), and three doses of La(NO3)3. Urine samples were collected over a 48-h time course and measured by 600 MHz NMR spectroscopy. Each spectrum was data-processed to provide 205 intensity-related descriptors used as input coordinates in a multidimensional space and analyzed by pattern recognition method. By NMR and principal components analysis (PCA) methods, the biochemical effects classification and time-course trajectories of various doses of La(NO3)3 were achieved. The toxicity of La(NO3)3 was similar to that of carbon tetrachloride according to the 1H NMR spectral profiles and toxicity classification. This work illustrates the high reliability of NMR-PR method using 1H NMR spectroscopy for the exploration and prediction of biochemical effects of rare earths in rats.