Pesticide residues
Pesticide is a synthetic chemical, a natural or biological substance, or a mixture thereof, used for prevention, termination and/or control of diseases, pests, grass or other living things which are hazardous to agriculture and forestry; or for regulation of the growth of plants and pests in an intended way. Excessive usage of pesticides will lead to large amounts of pesticide residues in crops. When we take too many pesticide residues into our bodies, it may cause acute poisoning, which conclude headaches, nausea, vomiting, diarrhea, difficulty breathing, etc. In long-term, it may even damage the liver and kidneys, nervous system, and endocrine system. system and immune system. It also causes cancer and affects fertility.
To ensure the health security of citizens, the Chinese Medicine Regulations (Cap. 549F of the Laws of Hong Kong) and the practice guidelines established by the Chinese Medicine Council of Hong Kong regulate the Chinese medicine retailers and wholesalers to keep the medicinal materials within the limits set and maintain transaction records. The accurate testing methods recognized by the Chinese Medicine Council under the Department of Health of Hong Kong for determining the content levels include:
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Gas chromatography with electron-capture detector (GC-ECD)
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Gas chromatography with tandem mass spectrometry (GC-MS/MS)
The targeted pesticides for the analysis of pesticide residues in CMM are listed as follows -
(a) Aldrin and Dieldrin (sum of)
(b) Chlordane (sum of cis-, trans- and oxychlordane)
(c) Dichlorodiphenyltrichloroethane (DDT) [sum of p,p’-DDT, o,p’-DDT, p,p’-dichlorodiphenyldichloroethylene (p,p’-DDE) and p,p’-dichloro-2,2-bis(4-chlorophenyl)ethane (p,p’-TDE)]
(d) Endrin
(e) Heptachlor (sum of heptachlor and heptachlor epoxide)
(f) Hexachlorobenzene (HCB)
(g) Hexachlorocyclohexane (BHC) isomers (α-, β- and δ-hexachlorocyclohexane)
(h) Lindane [γ-hexachlorocyclohexane (BHC)]
(i) Quintozene [sum of quintozene (PCNB), pentachloroaniline (PCA) and methyl pentachlorophenyl sulphide (MPCPS)]
"Hong Kong Chinese Materia Medica Standards"
The amount of pesticide residues in CMM samples should comply with the limits listed in Table 5 below, unless in the case of a CMM of mineral origin or as otherwise specified.
The maximum permitted limits of pesticide residues in CMM samples
With our sophisticated instruments, experienced chemists/microbiologists, and stringent QA/QC procedures, we assure that all the results reported by our laboratory are accurate and precise.
Enviro Labs Ltd. (ELL) uses the GS/MS method for detection, and HOKLAS accreditation has been granted for most of the pesticide residues tests. For details of the scope of accreditation, please refer to the HKAS website.
References
1. "Hong Kong Chinese Materia Medica Standards": Appendix VI Determination of Pesticide Residues