Malawi Adventist University, Malamulo College of Health Sciences Campus, Biomedical Science Department, Microbiology Research Group.
University of Malawi, Chancellor College, Zomba, Malawi.
Malawi Med J. 2020 Sep;32(3):153-159. doi: 10.4314/mmj.v32i3.8.
There has been an increase in use of herbal medicine worldwide. It is either used as a stand-alone or complementary therapy to conventional medicine due to past good experience, poverty and family traditions. In Malawi, there are no regulations governing the supply, acquisition, marketing and quality enforcement of herbal medicine. This compromises its safety thereby exposing consumers to avoidable bacteria and heavy metals leading to various adverse health effects.
Cross-sectional laboratory experiments were conducted to determine bacterial and heavy metal contamination of herbal medicine commonly sold in Blantyre, Malawi. A total of 47 samples which were in three formulations namely liquid, powder and tablet were used in the experiments. 29 samples were used for bacterial limit tests and 18 samples were used for heavy metal analysis. Bacterial contamination was determined by streak plate method and biochemical tests while heavy metals were determined by atomic absorption spectroscopy. Descriptive statistics and t-tests were calculated using Microsoft excel and SPSS software programs.
Twenty out of the 29 samples (68.9%) were contaminated with , coagulase negative Citrobacter and other-Coliform bacterial species. Most isolated microorganism was . (30%), followed by . (25%). Out of 20 contaminated samples, 75% were contaminated with coliforms. From these 75% which were contaminated with coliforms, 93.3% of them exceeded WHO regulatory limit (103 CFU/g for enterobacteria). Although liquid samples had the highest level of bacterial contaminants, the count was not statistically different from other formulations (P = 0.058). For heavy metals, lead and cadmium were detected and 67% of the samples had lead levels exceeding regulatory limits.
Levels of bacterial and lead contamination in herbal medicine from Blantyre markets are far above acceptable limits set by WHO and Canadian guidelines. The use of these herbal medicines is a major risk to the health of consumers.
在全球范围内，草药的使用有所增加。由于过去的良好经验、贫困和家庭传统，它要么作为独立的治疗方法，要么作为传统医学的补充疗法。在马拉维，没有法规来规范草药的供应、获取、营销和质量执行。这就使其安全性受到影响，使消费者面临可避免的细菌和重金属暴露，从而导致各种不良健康影响。
进行了横断面实验室实验，以确定在马拉维布兰太尔市常见的草药中的细菌和重金属污染。总共有 47 个样本，分为三种制剂，即液体、粉末和片剂，用于实验。其中 29 个样本用于细菌限量测试，18 个样本用于重金属分析。细菌污染通过划线平板法和生化试验确定，重金属通过原子吸收光谱法确定。使用 Microsoft excel 和 SPSS 软件程序计算描述性统计和 t 检验。
在 29 个样本中，有 20 个（68.9%）受到 凝固酶阴性 柠檬酸杆菌和其他-大肠菌群细菌的污染。分离出的最主要微生物是 凝固酶阴性 葡萄球菌（30%），其次是 大肠杆菌（25%）。在 20 个受污染的样本中，有 75%受到大肠菌群的污染。在这些受大肠菌群污染的样本中，有 93.3%超过了世界卫生组织的监管限值（103 CFU/g 肠杆菌）。尽管液体样本的细菌污染物含量最高，但与其他制剂相比，这一含量并无统计学差异（P=0.058）。对于重金属，检测到铅和镉，67%的样本的铅含量超过了监管限值。
布兰太尔市场的草药中的细菌和铅污染水平远远超过了世界卫生组织和加拿大指南规定的可接受限值。这些草药的使用对消费者的健康构成了重大风险。
