Yes, Tutmeric can be adulterated inspite of tall claim of the purities claimed by the manufacturers. The contaminants are rice - flour, saw- dust, starch, chalk, lead chromate, metanil yellow etc . The immediate - effects of such adulteration is not noticeable but in the long can cause liver and kidney disorder, skin - disease and even can cause nervous breakdown.
There are certain chemical tests for the identification of the impurities. In order to identify the contaminants, take a small quantity of Turmeric - powder in a test tube by properly dissolving it in water. Now, a few drops of concentrated sulphuric or hydrochloride acid has to be added in the test - tube. you may notice the development of pink - colour after some time. If the pink colour persists even after ten minutes. You can safely conclude that the powder is mixed with the impurities. But if the colour vanishes, it would indicate the purity of the substance.
In order to detect the presence of chalk in the sample, take a pinch of the sample dissolved in water in a test- tube, add a few drops of either sulphuric or hydrochloric acid, if effervescence takes place, we can say that sample is contaminated with chalk.