Contamination of herbal medicinal products in low-and-middle-income countries: A systematic review
Date
2023
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Heliyon
Abstract
The use of herbal medicinal products (HMPs) has grown significantly across low-and-middle income countries (LMICs). Consequently, the safety of these products due to contamination is a
significant public health concern. This systematic review aimed to determine the prevalence,
types, and levels of contaminants in HMPs from LMICs. A search was performed in seven online
databases, i.e., Africa journal online (AJOL), Cumulative Index to Nursing and Allied Health
Literature (CINAHL), Directory of Open Access Journals (DOAJ), Health Inter-Network Access to
Research Initiative (HINARI), World Health Organization Global Index Medicus (WHO GIM),
Scopus, and PubMed using appropriate search queries and reported as per the “Preferred
Reporting Items for Systematic Reviews and Meta-Analyses” (PRISMA) guidelines. Ninety-one
peer-reviewed articles published from 1982 to 2021 from 28 different countries across four
continents were included in the study. Although metals, microbial, mycotoxins, pesticides, and
residual solvents were the reported contaminants in the 91 articles, metals (56.0%, 51/91), mi crobial (27.5%, 25/91), and mycotoxins (18.7%, 17/91) were the most predominant. About
16.4% (1236/7518) of the samples had their contaminant levels above the regulatory limits.
Samples tested for microbial contaminants had the highest proportion (46.4%, 482/1039) of
contaminants exceeding the regulatory limit, followed by mycotoxins (25.8%, 109/423) and
metals (14.3%, 591/4128). The proportion of samples that had their average non-essential metal
contaminant levels above the regulatory limit was (57.6%, 377/655), 18.3% (88/480), 10.7%
(24/225), and 11.3% (29/257) for Pb, Cd, Hg, and As, respectively. The commonest bacteria
species found were Escherichia coli (52.3%, 10/19) and Salmonella species (42.1%, 8/19). This
review reported that almost 90% of Candida albicans and more than 80% of moulds exceeded the
required regulatory limits. HMP consumption poses profound health implications to consumers
and patients. Therefore, designing and/or implementing policies that effectively regulate HMPs to
minimize the health hazards related to their consumption while improving the quality of life of
persons living in LMICs are urgently needed.
Description
Research Article
Keywords
Microbial contamination, Chemical contamination, Metals, Pesticide residues