The Double-Edged Sword: Herbal Medicine's Promise and Peril in Ekiti State
A tradition steeped in nature, facing a modern-day toxic threat
In the heart of Nigeria's Ekiti State, where lush rainforests meet vibrant urban centers, a profound connection to herbal medicine (HM) defines daily life for millions. Here, the knowledge of plants and their curative properties is a cultural inheritance, passed down through generations. Recent research reveals a startling reality: 85% of Ekiti residents have used herbal medicines in the past two years 1 . Yet, this deep-seated tradition now faces a modern challenge, as scientific investigations uncover hidden dangers contaminating these natural remedies, posing significant public health concerns that demand urgent attention.
of Ekiti residents used herbal medicine in past 2 years
medicinal botanicals identified in ethnobotanical studies
of medicinal species now considered rare
of studied samples had metals above WHO limits
The Deep Roots of Herbal Healing
Herbal medicine is far more than alternative treatment; it is a core part of primary healthcare for a substantial majority of the population in Nigeria and across Africa 2 . In Ekiti State, this practice is deeply interwoven with cultural identity and practical necessity.
Statistical analysis reveals that HM use in Ekiti cuts across all demographics but shows significant associations with age, gender, education level, religion, income, and occupation 1 . This pattern illustrates how herbal medicine is deeply embedded in the social and cultural fabric of the region, serving diverse communities with varied needs and resources.
A Wealth of Botanical Knowledge
Ethnobotanical studies in Ekiti have documented an impressive diversity of plants valued for their medicinal properties. Research has identified 71 botanicals belonging to 41 different families used for ethnomedicinal purposes throughout the state 6 . These plants address a wide spectrum of health concerns, with particular focus on malaria and fever—predominant health challenges in the region.
Troublingly, approximately 40% of these valuable medicinal species are now considered rare, primarily due to deforestation, population growth, and urbanization 6 . This loss represents not just biodiversity decline but also the erosion of indigenous healthcare resources and cultural heritage.
Alstonia boonei (Ahun)
Used for malaria and rheumatism treatment
Vernonia amygdalina (Ewuro)
Used for hypertension management
Azadirachta indica (Dongoyaro)
Used for malaria, piles, and antiseptic purposes
| Botanical Name | Local Name | Part(s) Used | Traditional Medicinal Use |
|---|---|---|---|
| Alstonia boonei | Ahun | Stem, Bark | Treatment of malaria, rheumatism |
| Vernonia amygdalina | Ewuro | Leaves | Hypertension management |
| Azadirachta indica | Dongoyaro | Leaves, Bark | Malaria, piles, syphilis, antiseptic |
| Chromolaena odorata | Akintola | Leaves | Malaria treatment |
| Ocimum gratissimum | Efinrin-ajase | Leaves | Fever, cold, cough, diarrhea |
| Mangifera indica | Mangoro | Stem, Leaves, Bark | Malaria, diarrhea, diabetes |
| Sorghum bicolor | Poroporo | Leaves | Blood supplement, stomachache |
| Cymbopogon citratus | Beresi | Leaves | Anti-malarial properties |
Hidden Dangers in Natural Remedies
Despite the cultural importance and perceived safety of herbal medicines, growing evidence points to significant contamination issues that transform these potential healing agents into sources of harm. A groundbreaking interdisciplinary study combining public health and forensic chemistry approaches has revealed alarming toxic constituents in commonly used herbal preparations in Ekiti State 1 .
The Heavy Metal Threat
Laboratory analysis of ten commonly used herbal medicines identified in the Ekiti survey uncovered dangerous concentrations of heavy metals. Using Inductive Coupled Plasma-Optical Emission Spectroscopy (ICP-OES), researchers detected cadmium and copper at levels exceeding World Health Organization (WHO) permissible limits in all studied herbal samples 1 . One sample additionally contained lead and zinc above safety limits 1 .
These findings are particularly concerning because heavy metals accumulate in the body over time, leading to progressive toxicity even when consumed in small quantities. The implications for regular users of these preparations are severe, with potential damage to multiple organ systems including the kidneys, nervous system, and cardiovascular system.
Analytical Methods
ICP-OES and AAS used to detect heavy metals in herbal samples
Health Risk Index
HRI for lead >1 in multiple species indicates significant long-term health risks 5
Heavy Metal Health Risks
| Heavy Metal | Health Effects of Excessive Exposure | Cancer Risk Assessment |
|---|---|---|
| Lead (Pb) | Gastrointestinal irritation, appetite/weight loss, sleeplessness, fatigue, headache, neurological damage 5 | Ranged from low (10⁻⁶) to high (10⁻³) risk levels 5 |
| Cadmium (Cd) | Lung and prostate cancer, respiratory system injury, stomach irritation, vomiting, diarrhea 5 | Highly carcinogenic with chronic exposure 5 |
| Nickel (Ni) | Dermatitis, respiratory distress, genotoxicity, hematotoxicity, risk of lung and nasal cancer 5 | Ranged from acceptable to unacceptable risk levels 5 |
| Chromium (Cr) | Anemia, male reproductive system damage, gastrointestinal irritation, cardiovascular issues 5 | Hexavalent chromium is carcinogenic and can cause stomach tumors 5 |
A Closer Look at the Evidence: Ekiti's Herbal Medicine Analysis
To understand how researchers uncovered these hidden dangers, let's examine a pivotal experiment conducted on herbal medicines from Ado Ekiti urban market.
Methodology: Tracking Toxins Step-by-Step
Sample Collection
Researchers randomly selected ten commonly consumed herbal plants sold in Ado Ekiti urban market, identified with help from local vendors 5 .
Preparation
Glassware was meticulously cleaned with nitric acid to prevent cross-contamination. Plant samples were air-dried, ground into fine particles, and sieved 5 .
Digestion
One gram of each sample was digested with concentrated nitric acid, followed by heating and addition of perchloric acid until the sample turned light in color 5 .
Analysis
The digested samples were analyzed using Atomic Absorption Spectrometry (AAS) to detect and quantify heavy metal content 5 .
Risk Assessment
Researchers calculated Estimated Daily Intake (EDI), Health Risk Index (HRI), and Estimated Cancer Risk (ECR) to evaluate potential health impacts on both children and adults 5 .
Results and Implications: A Public Health Warning
The findings revealed that estimated daily intake of lead, nickel, chromium, copper, and manganese exceeded upper tolerable daily intake references for all studied plant species in both children and adults 5 . The health risk assessment painted an even grimmer picture:
- The HRI for lead was greater than 1 in multiple species including Alstonia congensis and Terminalia avicennioides, indicating significant long-term health risks 5 .
- The overall HRI for both children and adults followed the order: Mn > Cu > Ni > Pb > Cr 5 .
- Perhaps most alarming was the cancer risk assessment, which found that estimated cancer risks for lead, nickel, and chromium in some herbal plants ranged from acceptable (10⁻⁶) to unacceptable (10⁻³ for children; 10⁻² for adults) levels 5 .
Health Risk Index (HRI) > 1
Indicates significant long-term health risks from lead exposure in multiple herbal species 5
Cancer Risk Assessment
Ranged from acceptable (10⁻⁶) to unacceptable (10⁻³ for children; 10⁻² for adults) levels 5
Beyond Heavy Metals: Other Safety Concerns
While heavy metals present significant dangers, they represent just one facet of the safety challenges surrounding herbal medicines in Nigeria.
Alcohol in Disguise
Some herbal preparations, particularly those known as "Paraga," contain substantial alcohol content, often disguised as medicine. Studies of Paraga samples from motor parks in Southwest Nigeria found alcohol by volume (ABV) ranging from 1.20% to 20.84%—weaker than beer at the low end and stronger than wine at the high end 9 . These preparations are particularly popular among commercial drivers, raising concerns about alcohol-related road traffic injuries 9 .
Quality Control and Regulatory Gaps
The production of many herbal medicines involves no formal recipes, calibrations, or standardized weighing of ingredients 9 . This lack of standardization means components and concentrations can vary dramatically between batches, creating unpredictable potency and potential toxicity.
Additionally, the regulatory status of herbal medicines remains ambiguous in many contexts, with some products categorized simultaneously as foods, medicines, or dietary supplements, creating significant challenges for effective oversight and quality control 5 .
Paraga Alcohol Content
Alcohol by volume (ABV) in herbal preparations:
Range found in Paraga samples from Southwest Nigeria 9
Balancing Tradition and Safety
The findings from Ekiti State present a complex public health challenge: how to preserve valuable traditional knowledge and ensure healthcare access while protecting consumers from harm. The contamination of herbal medicines with heavy metals represents a significant yet preventable threat to community health.
"The preservation of both public health and cultural heritage depends on our ability to navigate this delicate balance with wisdom and evidence-based practice."
The Path Forward
Addressing this challenge requires a multi-faceted approach:
Provider Education
Working with traditional healers to improve safe harvesting and preparation practices
Public Awareness
Educating consumers about potential risks while acknowledging cultural importance
Legislative Action
Developing appropriate legislative frameworks for production, distribution, and safety monitoring of herbal medicines 1
As research continues to bridge the gap between traditional knowledge and modern scientific validation, the goal remains clear: to harness the healing power of nature while ensuring the safety of those who place their trust in these time-honored remedies.