WHO has established several guidelines for quality control and standardization of herbal medicines. This includes guidelines for crude plant materials, processed plant materials, and analytical procedures. Key aspects that must be standardized include authentication of plant identity and source, absence of contaminants, determination of marker compounds, and ensuring safety through tests for heavy metals, pesticides, and microbiological limits. Proper application of WHO guidelines can help ensure the quality, safety and efficacy of herbal medicines.

1. WHO Guidelines for Quality
Control & Standardization of
Herbal Drugs
By: Sandeep Kumar Singh
Pre Ph.D. Course work
Enrol No. Ph.D./PHR/12/033
Guru Ghasidas Vishwavidyalaya, Bilaspur

2. Contents
− Definitions of relevant terms
− Need of quality control
− Safety in quality management
− Ishikawa diagram
− Constraints in quality control of herbal drugs
− Three pillars of ideal herbal drug and their rational use
− World health organization
− Guidelines provided by WHO for herbals
− Standardization of herbal drugs crude plant Parts/plant material
− Processed plant materials/non-plant materials
− Flow diagram standardization
− Analytical procedures
− References
2

3. Herbal medicines are the oldest form of
healthcare known to humanity and has been used in
all cultures throughout history
3

4. 4
The definitions of terms that will be encountered in the
discussion are given:
 Quality : status of a drug that is determined by identity,
purity, content, and other chemical, physical or biological
properties
 Safety : to assure the drug didn’t have any hazardous effect
 Purity: not contaminated with potentially harmful substances
 Potency: is the content of active constituents within the
defined limits?
 Identity: is the herb the one it should be?
 Quality control : it refers to processes involved in
maintaining the quality and validity of a manufactured
product
Definitions of relevant terms

5. 5
Definition continued…
 Herbal preparations
are preparations obtained by scientific treatments such as
extraction, distillation, fractionation, purification, or
fermentation. These include comminuted or powdered herbal
substances, tinctures, extracts, essential oils and processed
exudates
 Herbal substances
are precisely defined by the plant part used (leaves,
stems, rhizomes, roots and bark)
Certain exudates that have not been subjected to a
specific treatment are also considered to be herbal substances
 Markers
are chemically defined constituents or groups of
constituents of a herbal substance, which are of interest for
control purposes, independent of whether they have any
therapeutic activity

6. Need of quality control
– Quality control and standardization
– Reduce adulterations with substandard drugs
– Improper authentication
– Scientific validation of the therapeutic claims
– Identity, purity, efficacy and safety
– Customer satisfaction and confidence
6

7. Adulteration with other
medicines
Mistaken use of wrong
species
Incorrect dosing
Poor quality products
Toxicity
Interactions with other
medicines
Problems
Misconception that all
herbs are safe
Misuse of herbal drugs
Safety in quality management

8. Ishikawa cause and effect diagram for content
variation of herbal drugs
8
*Shinde M.V., Dhalwal K., Potdar K., Mahadik K. Application of quality control principles to
herbal drugs. International Journal of Phytomedicine 1(2009); p. 4-8.

9. Regulatory Aspects
Adulteration/
Substitution
No Certification of Raw
Materials
Pharmacovigilence Data
Not Collected
Herbal Pharmacopoeia?
Lack of Public Test Houses
Lack of Safety Evaluation
Facility
Poor Investment In R&D Of
HMP
Constraints in Quality
Control of Herbal Drug
Products
Main Dependence on
Wild Sources
Lack of Trained Man
Power
Constraints in quality control of herbal drugs

10. Three pillars of ideal herbal drug and their
rational use
QUALITY
EFFICACY
SAFETY
AVAILABILITY
ACCESSABILITY
QUALITY
SAFETY
EFFICACY
Appropriate use of
herbal drug
10

11. World Health Organization
− The World Health Organization (WHO) is a
specialized agency of the United Nations (UN) that is
concerned with international public health
− It was established on 7 April 1948, with its headquarters
in Geneva, Switzerland
− WHO is a member of the United Nations Development
Group (UNDP)
− World Health Organization, provides guidelines for
prevention, control, safety, efficacy as well as
evaluation and standardisation of herbal materials (e.g.
WHO, 2005, 2002a,b, 1999a,b, 1998a,b, 1996a,b, 1990,
1981, 1979)
11

12. What WHO has done?

13. Guidelines provided by WHO for herbals
A set of guideline for the assessment of
herbal remedies has been published by
WHO. These guidelines specify criteria to
be used in evaluating commercial crude
drugs intended for use (WHO Traditional
Medicine Strategy 2002-2005).
WHO guidelines on safety monitoring of
herbal medicines in pharmacovigilance
systems (2004).

14. Quality control methods for medicinal
plant materials (1998).
WHO Guidelines on good
manufacturing Practices (GMP) for
Herbal Medicines (2005).
Guidelines continued…

15. WHO Monographs on Selected
Medicinal Plants:
Vol. 1 (1999)
Vol. 2 (2004)
Vol. 3 (2007)
Vol. 4 (2009)
Guidelines continued…

16. WHO Guidelines For Assessing
Quality of Herbal Medicine With
Reference to Contaminants and
Residues (2007).
Basic tests for drugs – Pharmaceutical
substances, Medicinal plants materials
and dosage forms (1998).
Guidelines continued…

17. General Guidelines for
Methodologies on Research and
Evaluation of Traditional Medicine
(2000).
WHO Guidelines on GACP for
Medicinal Plants (2003).
Guidelines continued…

18. Research Guidelines for Evaluating the
Safety and Efficacy of Herbal
Medicines (1993).
Regulatory Situation of Herbal
Medicines - A Worldwide Review
(1998).
Guidelines continued…

19. Standardization of herbal drugs crude plant
parts/plant material
Definition:
− name of plant
− part of plant
− Nature/condition of material: whole, powdered, fresh, dried, etc
Authentication/confirmation of:
− Correct geographical origin
− Correct stage of growth
Absence of foreign matter:
− other plant parts or materials
− soil, stones, dust
− insects and other animal matter (as determined by microscopy, macroscopy, chromatography)
Microscopic characteristics confirming identity:
− qualitative features
− quantitative features, (e.g. stomatal number)
Radioactive contamination limits: arising from environmental pollution or microbial
decontamination procedures
Assay: for materials containing constituents of known therapeutic activity, or known unique (marker)
compounds. Non-specific assay methods for groups of compounds may be used where specific
assay methods are not available for single compounds
19

20. Processed plant materials/non-plant materials (extracts,
tinctures, comminutions etc.)
Definition: liquid, solid, etc
Organoleptic characteristics:
− Macroscopy
− Smell
− Taste
− Texture
− Colour
Chromatographic profile using more than one method:
− to confirm presence of unique compounds (markers)
− to confirm characteristic TLC chromatogram
− to confirm characteristic HPTLC chromatogram (TLC + densitometry = HPTLC)
Water content (for hygroscopic materials):
Ash values: indicate extent of contamination with inorganic material. Determined by
incineration. Values include acid insoluble and sulphated ash
Volatile matter: for plants containing volatile oils:
− Determined by steam
− Distillation
Powdered material: test method and acceptable limits for particle size, distribution
20

21. continued...
If the product is a mix of plant materials, the supplier must provide evidence that
each
component plant has been individually tested.
Heavy metal limits: from environmental pollution and pesticides
Microbial contamination limits: microbial contamination arises from cultivation,
harvesting, processing and storage:
− confirmation of absence of E. coli, S. aureus, P. aeruginosa and
− Salmonella
− limits for aflatoxins (fungal toxins)
Residual solvents from processing
Pesticide residue limits: arising from cultivation (FAO and WHO limits)
Extractive values: extraction by different solvents indicates proportion of polar and
non-polar components
Assay: for materials containing constituents of known therapeutic activity, or known
unique (marker) compounds;
− Non-specific assay methods for groups of compounds may be used where
specific assay methods are not available for single compounds
21

22. QUALITY EVALUATION
OF HERBAL DRUGS
Standardization & quality evaluation of herbal drugs
22

23. Analytical procedures
Botanical parameters:
– Sensory evaluation: including visual macroscopy/
touch/odour/taste
– Foreign matter: including foreign plants, foreign
animals, foreign minerals, etc.
– Microscopy: including histological observation and
measurements
23
*Aggrawal, S.S., Herbal Drug Technology. Universities Press, 2002.
** Rangari, V.D., Text book of Pharmacognosy and Phytochemistry Vol. I , Carrier Pub., 2006.

24. continued…
Physico-chemical methods:
− Ash values: Total, acid insoluble, water soluble
− Extractive values: in hot water, cold water and ethanol,
− Volatile matter: Loss on drying,
− Volatile oils: by steam distillation.
− Determination of crude fibers,
− Determination of moisture content.
24

25. continued…
Biological parameters:
− Bitterness value: unit equivalent bitterness of standard
solution of Quinine HCI
− Hemolytic property: on ox blood by comparison with
standard reference solution of saponin
− Astringent property: tannins that bind to standard
Frieberg Hide powder
− Swelling index: in water
− Foaming index: foam height produced by 1g material
under specified conditions
25

26. continued…
Toxicological parameters:
These include the various identification procedures:
− Arsenic: stain produced on HgBr2 paper in comparison
to standard stain
− Pesticide residues: including total organic chloride and
total organic phosphorus
− Heavy metals: like cadmium, mercury and lead
− Microbial contaminations: total viable aerobic count of
pathogens; viz. Enterobacteriaceae, E. Coli, Salmonella,
P. aeruginosa, S. aureous, (e.g. Mellilotus officinalis)*
− Aflatoxins: by TLC using standard aflatoxins (B1, B2, G1
and G2)
− Radioactive contaminations
26
*Warude D., Patwardhan B. Quality and Regulatory Issues. Journal of Scientific and
Industrial Research. Vol. 64, Feb 2005; p. 83-92.

27. References
− Aggrawal, S.S., Herbal Drug Technology. Universities Press, 2002.
− EMEA. Guidelines on Quality of Herbal Medicinal Products/Traditional
Medicinal Products, EMEA/CVMP/814OO Review. European Agency
for the Evaluation of Medicinal Products (EMEA), London, 2005.
− Mukherjee, P.W. Quality Control of Herbal Drugs: An Approach to
Evaluation of Botanicals. Business Horizons Publishers, New Delhi,
India, 2002.
− Rangari, V.D., Text book of Pharmacognosy and Phytochemistry Vol. I ,
Carrier Pub., 2006.
− Shinde M.V., Dhalwal K., Potdar K., Mahadik K. Application of quality
control principles to herbal drugs. International Journal of Phytomedicine
1(2009); p. 4-8.
− WHO. Quality Control Methods for Medicinal Plant Materials, World
Health Organization, Geneva, 1998. WHO. Guidelines for the
Appropriate Use of Herbal Medicines. WHO Regional Publications,
Western Pacific Series No 3, WHO Regional office for the Western
27

28. continued…
− WHO. The International Pharmacopeia, Vol. 2: Quality Specifications,
3rd edn. World Health Organization, Geneva, 1981.
− WHO. Quality Control Methods for Medicinal Plant Materials. World
Health Organization, Geneva, 1999.
− WHO. WHO Global Atlas of Traditional, Complementary and
Alternative Medicine. 2 vol. set. Vol. 1 contains text and Vol. 2, maps.
World Health Organization, Geneva, 2005.
− WHO. Guidelines on Good Agricultural and Collection Practices
(GACP) for Medicinal Plants. World Health Organization, Geneva, 2004.
− Warude D., Patwardhan B. Batanicals: Quality and Regulatory Issues.
Journal of Scientific and Industrial Research. Vol. 64, Feb 2005; p. 83-92.
28

29. THANK
YOU
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