Although whole, dried, or fresh turmeric are typically free of contamination, turmeric powder with low levels of curcumin can be adulterated with chemicals as substitutes for curcumin. Adulterants added to give the color to turmeric are dyes such as metanil yellow and lead chromate, which can seriously affect the nervous system and may be carcinogenic. Sometimes, ingredients such as starch, chalk powder, and saw dust are added as fillers which may end up harming the body on long term.
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