Dietary lead exposure from vegetables: A global assessment of contamination patterns and health risks.

Potentially Toxic Elements in Foods Consumed in Uganda: Occurrence, Dietary Exposure, and Public Health Risks

Potentially toxic element (PTE) contamination of food systems has emerged as an important environmental and public health concern in many developing countries, including Uganda, owing to rapid urbanization, industrialization, mining activities, wastewater reuse, informal waste disposal, and expanding urban agriculture. This review synthesizes evidence from peer-reviewed and selected grey literature on the occurrence of cadmium (Cd), chromium (Cr), nickel (Ni), lead (Pb), and arsenic (As) in cereals, vegetables, tubers, livestock products, fish, fruits, and processed foods consumed in Uganda. A structured literature synthesis and screening-level dietary risk assessment using estimated daily intake (EDI), target hazard quotient (THQ), hazard index (HI), carcinogenic risk (CR), and total carcinogenic risk (TCR) were conducted to identify contamination hotspots, priority exposure pathways, and potential public health implications. The available evidence revealed substantial spatial variability, with contamination consistently concentrated in mining-influenced agricultural areas, wastewater-irrigated farms, municipal dumpsites, industrial corridors, and urban food markets. Vegetables, cereals, livestock products, fish, and street-vended foods exhibited the greatest contamination burdens, while Pb and Cd were the PTEs most frequently reported exceeding WHO/FAO, Codex Alimentarius, and Ugandan food safety limits. Screening-level risk estimates indicated that Pb, Cd, and Cr contributed most to cumulative dietary exposure, with children consistently exhibiting higher EDI, THQ, HI, and TCR values than adults because of greater food intake relative to body weight. Although cumulative HI and TCR values exceeded recommended screening thresholds in several hotspot regions, these estimates should be interpreted as conservative screening-level indicators derived from heterogeneous published datasets rather than nationally representative measures of dietary exposure. Overall, the evidence indicates that PTE contamination in Ugandan food systems is predominantly hotspot-driven and highlights the need for targeted surveillance, standardized monitoring and reporting, improved pollution control, and strengthened food safety management to reduce chronic dietary exposure and protect public health.

Mercury exposure from fish consumption: A systematic review and meta-analysis of health risks and effects in urban vs. rural settings

The meta-analysis showed substantially higher mercury levels in rural populations than in urban populations, highlighting the need for targeted public health strategies to mitigate mercury exposure while maintaining the nutritional benefits of fish consumption.

Blood lead levels (BLLs), exposure pathways and health impacts in South Asia: a comprehensive review

Abstract Lead remains a pervasive toxicant in South Asia. We compiled published blood lead levels (BLLs), food, and environmental lead concentrations from South Asia (India, Bangladesh, Pakistan, Nepal and Sri Lanka) to identify the primary sources contributing to population exposure. Across all regions, reported BLLs frequently exceeded the current Centers for Disease Control and Prevention (CDC) reference value of 3.5 µg/dL. Elevated BLLs were consistently associated with adverse health outcomes, including neurocognitive impairment, anemia, hypertension, renal and hepatic dysfunction, and oxidative and genotoxic effects in both children and adults. Comparative assessment of lead concentrations across environmental media indicated significant contamination of dietary sources, with rice, vegetables and spices emerging as a major contributor to population exposure. However, airborne lead also played major role particularly in densely populated industrial settings. Correlation analysis demonstrated positive association between literature derived BLL and lead concentration in numerous environmental media, emphasizing the cumulative influence of multi pathway lead exposure. Despite heterogeneity in study designs and geographic coverage, the findings confirmed that non-fuel sources now dominate the lead exposure in South Asian regions. This review highlights the critical need for enhanced food safety regulations, reinforced environmental monitoring and targeted public health interventions in order to mitigate lead exposure and its related health impacts especially in vulnerable populations.

Dietary exposure and health risks associated with selected vegetables from Pothohar Region of Punjab, Pakistan

Quantifying the global burden of lead exposure from dietary lead intake

Background: Lead exposure is estimated to cause approximately 3.5 million premature deaths a year, yet the key ongoing sources of lead exposure are unclear. Methods: We estimated the contribution of dietary lead intake to global blood lead levels (BLLs) for 7-year-old children and 22-year-old adults by applying the All-Ages Lead Model (AALM) to calculate blood lead levels (BLLs) based on 25 total diet studies (TDS) that quantify dietary lead intake across 46 countries. Results: For children, the population-weighted average dietary lead intake in low- and middle-income countries (LMICs) (32.0 g/day) was found to be more than three times higher than in high-income countries (HICs) (9.3 g/day), and more than 10 times higher than the FDA reference level for children (2.2 g/day). The average impact on BLLs for children is estimated to be near 29 g/L in LMICs and near 12 g/L in HICs. Averaged across the TDS data, vegetables (27%) and cereals (24%) were found to contribute the most to dietary lead. Conclusions: While there are limitations associated with biokinetic modelling and the TDS data from LMICs, these results suggest that the contribution of dietary lead intake to global lead exposure is in the region of 40 to 50%, suggesting, in turn, that dietary lead intake is likely a major global driver of lead poisoning. Lead absorbed from the environment into food crops is expected to be the key driver of dietary lead. Current regulatory levels for maximum lead concentrations in foods (0.05-0.3 mg/kg) are out-of-date and may imply a dietary lead intake of 200 g/day, far higher than the FDA reference level (2.2 g/day). Collecting representative TDS data in high lead burden countries should be a priority. Further research is also recommended on upstream lead sources and pathways of lead uptake in plants, driving global food contamination.

Antimicrobial and Pesticide Residues in Animal-Source Foods in Bangladesh: A Meta-Analysis with Probabilistic Dietary Exposure and Health-Risk Assessment.

Intensifying livestock, poultry and aquaculture production in Bangladesh has been accompanied by unregulated antimicrobial and persistent organochlorine pesticide use, yet no national synthesis has linked residue occurrence in animal-source foods (ASF) to consumer health risk. This study aimed to pool the prevalence and concentration of antimicrobial and pesticide residues in Bangladeshi ASF and to estimate dietary exposure and risk using deterministic and probabilistic frameworks benchmarked against health-based guidance values. Following PRISMA 2020, five databases were searched from January 2010 to April 2026. Random-effects models (Freeman-Tukey transformation, DerSimonian-Laird estimator) pooled prevalence across five matrices. Estimated daily intakes were combined with national consumption data and JECFA/JMPR acceptable daily intakes (ADI) to derive hazard quotients (HQ), a cumulative hazard index (HI) and margins of exposure (MOE); a 10 000-iteration Monte-Carlo simulation characterized high-consumer (P95) exposure. Thirty-five studies (5 255 samples) were analyzed. Pooled prevalence was 12.9% (95% CI 8.8-17.6; I2 = 95.8%), highest in farmed fish (40.3%) and lowest in egg (4.7%); tetracyclines, fluoroquinolones and organochlorines predominated. For the average adult all HQ were ≪ 1 and the cumulative HI was 0.031; heptachlor and dieldrin dominated (P95 %ADI 6.2 and 4.7). The child HI (≈ 0.062) remained below unity; chloramphenicol P95 MOE fell to 253. Central-tendency dietary risk is low, but high-consumer tails, cumulative exposure, prohibited-substance detection and small-study effects justify strengthened, Codex-aligned residue surveillance, withdrawal-period enforcement and risk-based national monitoring within a One-Health framework.