How safe are TCM herbs in Singapore, given that China TCM herbs are known to contain high levels of lead, metals and pesticides?

Traditional Chinese medicines are broadly classified into two types:

I) Medicinal materials (from plants, animals, or minerals in their natural states, or in processed forms that have undergone simple processing, such as trimming or desiccation.

II) Chinese proprietary medicine (CPM) (finished form such as capsule, tablets and granules). As of now, only CPMs are subject to pre-market approval and licensing for their import and sale in Singapore.

I have attached the links on HSA regulatory framework on medicinal materials and CPMs for the ease of your reading.

Guidelines for Traditional Medicinal Materials:

http://www.hsa.gov.sg/content/hsa/en/Health_Products_Regulation/Complementary_Health_Products/Guidelines_for_Traditional_Medicinal_Materials.html

Regulatory framework pertaining to CPM:

http://www.hsa.gov.sg/content/hsa/en/Health_Products_Regulation/Complementary_Health_Products/Chinese_Proprietary_Medicines.html