SOURCES OF IMPURITIES IN PHARMACEUTICAL SUBSTANCES : -

 impure chemical compound :-

a compound is said to be impure if it is having foreigen matter in any pharmaceutical drug or any substances ,eg; impurities.

pure chemical compound :-

- a pure chemical compound reffers to that compound which is having no foreigen matter in any substances.

- chemical purity means freedom from various foreigen matter in substances. 

- practically or analytically 100% pure substances are not available for pharmaceutical method and traces of impurities must be present all substances.v

impurity means undesired material or practicals.

presense of impurity in the pharmaceutical substances may produces various toxic effect in human body and may also lower down the active strength of main drug or our pharmaceutical substances.

commonly present impurities in pharmaceutical substances include small quantities of chloride ,sulphite ,, lead,arsenic and various heavy metals etc. 

IMPURITIES COMMONLY FOUND IN PHARMACEUTICAL SUBSTANCES : -

[1] - impurities which have toxic effects on human body and bring about unpleasent reactions when present beyonds specific limits in various substances eg; arsenic and lead .

[2] - the impurities which are able to make substances incompatible with other substances .

[3] - the impurities which present beyonds limit sometime affects storage properties of drug substances.

[4] - sometimes impurities are present in substances but it is harmless .in this condition the amount of impurity lowers the active strength of the main drug substances or medicinal compound eg; sodium solution in pottesium salt.

[5] - sometime impurities may bring about technical proplans in the use of  substances.

[6] - impurities present in compoundn may also change some properties of compound such as test , order , colour which can be easilly ditected by sences and other identification procedures ex; sodium chloride becomes damp due to presense of magnissium salt.