Drug Adulteration
Drug Adulteration
This chapter is prepared for PharmD students in accordance with the officially endorsed curriculum in Pakistan.
October 23, 2024
Chapter outline
» Introduction
» Types of adulteration
› Inferiority
› Spoilage
› Deterioration
› Admixture
› Sophistication
› Substitution
Introduction
» Definition: The adulteration refers to the act of deliberately adding inferior, harmful, or unauthorized substances to a product to increase its quantity or alter its quality, usually for economic gain
› Adulteration in market samples is one of the greatest drawbacks in the promotion of herbal products
› It is found that the adverse event reports are not due to the intended herb, but rather due to the presence of an unintended herb (adulterant)
» Adulteration is done to earn more profit, for example;
› When the drug is scarce
› Drug is available but its price is high
» Adulterants must be such materials which are cheap and available easily and in large quantities
» Adulteration may also occur accidentally, for example;
› Confusion in vernacular names between indigenous systems of medicine and local dialects
› Lack of knowledge about the authentic plant
› Similarity in morphology and or aroma
› Careless collection
Types of adulteration
» Adulteration involves different conditions, as described below
Inferiority
» Inferiority refers to any substandard drug or substance regardless of cause
» For example, the dried, ripe seeds of Strychnos nux-vomica containing less than 1.15% of strychnine would be an inferior
» Milk, offered for sale at retail, is usually required to contain not less than 3% of butterfat
› If water is added to the milk containing 4% of butterfat to reduce the butterfat to 3%, it is considered adulterated
› But if all the butterfat is separated from this milk in the form of cream and then enough butterfat is added to give the required 3% of butterfat, it is not considered adulterated
» A somewhat similar procedure is being followed for some drugs, notably powdered opium
› The standard for powdered opium is not less than 10% and not more than 10.5% of anhydrous morphine
› Powdered opium containing a higher percentage of alkaloids may be admixed with inferior or exhausted powdered opium to bring the amount of morphine in the mixture to the stated percentage (10% to 10.5%)
› Such an admixture is not considered adulteration
» Furthermore, the official compendia permit this practice to be followed for powdered extracts, and they list the permissible diluents that may be used
Spoilage
» Spoilage refers to a form of substandard drug in which the quality or value or usefulness of the article has been so impaired or destroyed by the action of fungi and bacteria as to render the article unfit for human consumption
» Many examples of spoilage are found in the food industry, particularly in fresh fruits, vegetables, meats, fish, and seafood
Deterioration
» The term deterioration is applied to any impairment of the quality or value of an article by the abstraction or destruction of valuable constituents by distillation, extraction, aging, moisture, heat, fungi, insects, or other means
» Examples of deterioration;
› Whole cloves from which part of the volatile oil has been removed by distillation
› Ground linseed from which part of the fixed oil has been expressed
› Lard (a semi-solid white fat product) in which the fats have to some extent decomposed to form fatty acids
› Coffee that has largely lost its caffeine through over-roasting
Admixture
» Admixture is the addition of one article to another through accident, ignorance, or carelessness
» If the admixture is done intentionally to defraud, it is called ‘sophistication’
» An example of admixture is buchu leaves containing a few stems
› Another example is sarsaparilla root with some adhering soil
» If an admixture exceeds the established standard, it legally becomes an adulteration
Sophistication
» Sophistication means the addition of a spurious or inferior material to any article with intent to defraud
» The addition of wheat flour to powdered ginger, with enough capsicum to restore or enhance the pungency and enough curcuma to maintain the color, would represent a typical example of sophistication
» Sophistication is sometimes referred to as true adulteration
Substitution
» Substitution occurs when an entirely different article is used or sold in place of the one required or requested
» For example, cottonseed oil sold as olive oil
› Another example is American saffron sold as Spanish saffron
♦ Why do we learn and perform organoleptic, microscopic, and physical evaluations of crude drugs in our lab?
♦ Why a person dealing with herbal medicines should be an expert in the evaluation of crude drugs?
Reading References
» Tyler VE, Brady LR, Robbers JE. Pharmacognosy. Lea & Febiger, 7th edition, 1976.