Tuesdayâs debate between the Democratic presidential candidates, including Hillary Clinton and Bernie Sanders, will be streamed online for free. CNN, which is hosting the debate, will have it available on CNN.com and on the networkâs mobile apps. Coverage begins at 8:30 p.m.
Paraphenylenediamine (PPD) is a chemical substance that is widely used as a permanent hair dye. It may also been found in textile or fur dyes, dark coloured cosmetics, temporary tattoos, photographic developer and lithography plates, photocopying and printing inks, black rubber, oils, greases and gasoline.
What is a PPD? PPD stands for purified protein derivative, which is the solution used for the test. Alternative names you may hear the test called are tuberculin skin test, TB test and Mantoux test. During the procedure, a small amount of the solution is injected with a needle, right under the skin of the inner forearm.