Herbs are among the earliest source of medicines and have been used worldwide (WHO, 2002). Nowadays, herbs can be obtained in various dosage forms such as tablets, capsules, syrup, creams and plaster. However, have you ever stop and think, are the herbs which are categorized as traditional medicines really safe to be consumed?
Public may think that traditional medicines originating from natural sources are not dangerous and safe to be consumed. However, herbs can be potentially contaminated with heavy metals which come from the soil, water or air. Ernst (2002) reported there were cases of Arsenic, Mercury, Lead and Cadmium toxicities cases from consumption of traditional products from Asia. It shows that traditional medicines can also be contaminated with toxic metals.
Traditional products originating from herbs can be contaminated with bacteria and fungus as well. The bacteria and fungus can contaminate the herbs, for example in the post harvesting process, drying is not carried out properly.
In Malaysia, National Pharmaceutical Control Bureau (NPCB) as the secretariat of Drug Control Authority (DCA) ensures the safety and quality by registration of traditional products. Lab testing is performed to confirm the heavy metals are not exceeding the limits, to ensure the traditional products are not contaminated with pathogenic microorganisms and not adulterated with scheduled poisons. Disintegration and uniformity of weight tests are also performed for the traditional medicines which are in the form of tablets and capsules.
Traditional products testing
Heavy metals including arsenic, mercury, lead and cadmium can cause serious toxic effects as listed in table 1 below.
|Heavy metals||Toxic effects|
|Arsenic||Effects on skin and can cause cancer|
|Mercury||Effects on kidneys, lungs, nervous system|
|Lead||Effects on nervous system, cardiovascular system|
|Cadmium||Effects on lungs and kidney|
Table 1: Effects of heavy metal to the health
As the secretariat of DCA, National Pharmaceutical Control Bureau (NPCB) is responsible to analyze and ensure the level of heavy metals not exceeding the limit as stated in table 2. Tests are performed pre and post registration of traditional products. Therefore the public will consume only safe and of quality traditional products.
|Heavy metals||Toxic effects|
|Arsenic||NMT 5.0 mg/L or 5.0 mg/kg [5.0 ppm]|
|Mercury||NMT 0.5 mg/L or 0.5 mg/kg [0.5 ppm]|
|Lead||NMT 10.0 mg/L or 10.0 mg/kg [10.0 ppm]|
|Cadmium||NMT 0.3 mg/L or 0.3 mg/kg [0.3 ppm]|
Table 2: Limit of heavy metals in traditional products
Apart from chemical testing, traditional products are also tested to ensure it is not contaminated with pathogenic bacteria and fungus which can cause death.Traditional products should be free from Staphylococcus aureus, Eschericia coli, Salmonella and Pseudomonas aeruginosa. Staphylococcus aureus is commonly found on the skin and respiratory tract. Pseudomonas aeruginosa is usually originates from the soil and Eschericia coli comes from the faeces may potentially contaminate the herbs. Salmonella usually infecting the animals and indirectly can also contaminate the herbs.
Screening of adulterants in the products with certain indications is also performed by NPCB to ensure traditional products are not adulterated by scheduled poisons. The indications include:
- For men’s health
- For weight reduction
- For muscles and joints pain
- For cough and cold
- For reducing glucose level (type of tests is screening of anti-diabetic medicines)
NPCB as the secretariat of DCA is responsible to ensure traditional products in the market are safe and of quality. Consumer is responsible to check the traditional products which they purchase have the MAL number and hologram. The purchase of unregistered products can expose the consumers to the risks which are harmful to them and can be fatal.