Clinical Pharmacist and Master’s student in Clinical Pharmacy with research interests in pharmacovigilance, behavioral interventions in mental health, and AI applications in clinical decision support. Experience includes digital health research with Bloomsbury Health (London) and pharmacovigilance practice in patient support programs. Published work covers drug awareness among healthcare providers, postpartum depression management, and patient safety reporting. 
Clinical Pharmacist and Master’s student in Clinical Pharmacy with research interests in pharmacovigilance, behavioral interventions in mental health, and AI applications in clinical decision support. Experience includes digital health research with Bloomsbury Health (London) and pharmacovigilance practice in patient support programs. Published work covers drug awareness among healthcare providers, postpartum depression management, and patient safety reporting. What was reviewed
This review synthesizes evidence on heavy metal toxicity in poultry by focusing on four priority contaminants—arsenic (As), lead (Pb), cadmium (Cd), and mercury (Hg)—and tracing how they enter poultry systems through contaminated water, fodder/feed, industrial emissions, fertilizers, pesticides, and waste streams. The author frames these metals as both a flock-health problem and a food-chain problem, emphasizing organ bioaccumulation (especially kidney and liver) and downstream metabolic, structural, and functional damage. The review’s practical centerpiece for certification work is its consolidation of “normal range” versus “toxic concentration” values across tissues and products (meat and eggs), alongside descriptions of exposure-dependent pathology and oxidative-stress mechanisms that can be used to justify test matrices, target tissues, and decision thresholds.
Who was reviewed
Rather than enrolling a single cohort, the article reviews multiple field and experimental reports spanning diverse poultry contexts and geographies, including samples drawn from markets and production areas in Türkiye, Malaysia, Nigeria, Pakistan, Saudi Arabia, China, Bangladesh, Tunisia, Thailand, India, Iraq, and Iran. The “who” therefore includes different poultry types (e.g., broilers, layers, domestic chickens) and different exposure scenarios (industrial proximity, mining areas, manure-amended soils, and contaminated feed/water pathways), with measurements made in edible tissues (meat, liver, kidney) and consumer-relevant products (eggs). This broad source base is used to illustrate that heavy-metal burdens often concentrate in offal (kidney/liver) more than muscle, which is directly relevant for HMTC risk communication and for setting product-category testing rules.
Most important findings
For HMTC, the review’s most actionable contribution is its cross-country compilation of tissue- and egg-specific toxicity benchmarks and its clear warning that chronic low-dose exposure can still drive organ damage and measurable contamination in products.
| Critical point | Details |
|---|---|
| Bioaccumulation targets testing priority | The review states that As, Pb, Cd, and Hg bioaccumulate mainly in kidneys and liver (and also reproductive organs and lungs), making these tissues sentinel matrices for surveillance and supplier qualification. |
| Table 1 provides “normal vs toxic” reference values across tissues and eggs | Examples include Cd liver 0.039 mg/kg (normal) vs 0.050 mg/kg (toxic) in Türkiye, and Cd kidney 0.011 mg/kg (normal) vs 0.075 mg/kg (toxic). It also lists egg-related values such as Cd egg 0.388 ppm (normal) vs 19 ppm (toxic) in Saudi Arabia, and Hg egg 6.60 μg/kg (normal) vs 33.10 μg/kg (toxic) in Thailand. |
| Field measurements show wide variability and “hotspot” risk | Reported ranges can be very broad in kidneys/liver (e.g., Cd 0.075±0.010 to 15.763±0.012 mg/kg; Pb 1.85±0.007 to 11.838±0.005 mg/kg in kidney/liver), reinforcing that supplier location and feed/water sourcing can dominate risk. |
| Histopathology links contamination to measurable biological harm | At Cd 50 mg/L in drinking water, kidney findings included congestion, tubular degeneration/desquamation, hyaline casts, interstitial nephrosis, necrosis, and glomerular hypercellularity—evidence supporting HMTC’s preventive rationale beyond mere compliance. |
| Mechanistic emphasis supports biomarker-aligned monitoring | Pb is described as driving oxidative stress via free radicals and weakening antioxidant defenses, while Hg toxicity is tied to oxidative stress and immune disruption; the conclusion explicitly links heavy-metal overexposure to oxidative stress and multi-organ production losses. |
| Risk ranking can guide prioritization | The conclusion proposes that across reports, Cd tends to accumulate at the highest concentrations, followed by As, Pb, and Hg, and that impact severity commonly begins with liver then kidney, brain, and reproductive system—useful for tiered HMTC hazard planning. |
Key implications
For HMTC, heavy metal toxicity in poultry supports tighter supplier controls on feed, water, manure/fertilizer inputs, and industrial proximity, because chronic low-dose exposure can still yield organ accumulation and product contamination. Certification should prioritize Cd, then As/Pb/Hg, and require routine testing of eggs plus differentiated rules for offal versus muscle using Table 1’s normal-to-toxic contrasts as justification. Industry application includes risk-based lot testing, vendor qualification, and targeted audits in hotspot regions. Research gaps include harmonized thresholds and better linkage between field levels and consumer-health limits. Practical recommendations are to standardize matrices (egg, liver/kidney, muscle), adopt action levels below “toxic” where feasible, and document corrective actions when trends rise.
Citation
Aljohani ASM. Heavy metal toxicity in poultry: a comprehensive review.Frontiers in Veterinary Science. 2023;10:1161354. doi:10.3389/fvets.2023.1161354
Heavy metals are high-density elements that accumulate in the body and environment, disrupting biological processes. Lead, cadmium, arsenic, mercury, nickel, tin, aluminum, and chromium are of greatest concern due to persistence, bioaccumulation, and health risks, making them central to the HMTC program’s safety standards.
Arsenic is a naturally occurring metalloid that ranks first on the ATSDR toxic substances list. Inorganic arsenic contaminates water, rice and consumer products, and exposure is linked to cardiovascular disease, cognitive deficits, low birth weight and cancer. HMTC’s stringent certification applies ALARA principles to protect vulnerable populations.
Lead is a neurotoxic heavy metal with no safe exposure level. It contaminates food, consumer goods and drinking water, causing cognitive deficits, birth defects and cardiovascular disease. HMTC’s rigorous lead testing applies ALARA principles to protect infants and consumers and to prepare brands for tightening regulations.
Cadmium is a persistent heavy metal that accumulates in kidneys and bones. Dietary sources include cereals, cocoa, shellfish and vegetables, while smokers and industrial workers receive higher exposures. Studies link cadmium to kidney dysfunction, bone fractures and cancer.
Mercury (Hg) is a neurotoxic heavy metal found in various consumer products and environmental sources, making it a major public health concern. Its regulation is critical to protect vulnerable populations from long-term health effects, such as neurological impairment and cardiovascular disease. The HMTC program ensures that products meet the highest standards for mercury safety.
