Heavy Metal Index

p4-batch8-2026-05-13

5 min read

P4 Batch 8 — Ingest Report

Date: 2026-05-13 Handles processed: 200 (food-matrix-filtered P4, all 2024, positions 1000–1199) Source pages created: 14 False positives: 186 (93%)

Summary

Batch 8 continues the all-2024 slice. Yield is 14 pages. High-value finds: zhao2024 is a major global food-matrix metals review synthesizing 25+ TDS datasets across food categories — the broadest occurrence synthesis in the corpus to date. alrashdi2024 provides HPLC-ICP-MS speciated iAs in Saudi Arabian rice markets. barquero2024 documents the highest tHg/MeHg ever recorded for largemouth bass (7.61 mg/kg ww), from the Almadén mercury mine district. Total source pages: 431.

Source Pages Created

Group 1 (FM_11541783 – FM_11617724)

alrashdi2024-rice-ias-cd-pb-hg-saudi-arabia (FM_11569018) HPLC-ICP-MS speciated iAs, plus Cd, Pb, Hg in 33 rice samples (24 imported, 9 local Hassawi) from Saudi Arabian markets. Imported rice mean iAs 73 µg/kg. Evidence tier: A. Metals: iAs, Cd, Pb, tHg. Matrices: rice-grain. Jurisdictions: SA.

li2024-rice-cadmium-governance-china (FM_11561291) Seven-year field study, 180,000 ha, Xiangjiang Basin China. Integrated governance (water management + lime application + cadmium-safe varieties) achieved 57–78% Cd reduction in rice grain; all samples below 0.2 mg/kg China standard from 2018–2020. n=1.76M monitoring points. Evidence tier: A. Metals: Cd. Matrices: rice-grain. Jurisdictions: CN.

ibrahim2024-food-heavy-metals-nigeria (FM_11580069) AAS, n=361 raw staple food samples, 4 LGAs of Jigawa State, Nigeria. Anomalously high Hg values (medians 2.5–3.1 mg/kg) flagged for methodological caution; Cd normal; 4.2% elevated Pb. Flagged caveat on Hg values noted in source page. Evidence tier: A. Metals: Pb, Cd, tHg. Matrices: staple-foods. Jurisdictions: NG.

zhao2024-toxic-metals-metalloids-food-review (FM_11588791) High priority. Global review synthesizing occurrence data across 25+ food categories from TDS surveys in 19+ countries. Key anchors: rice iAs 17.6% of global samples above infant 0.1 mg/kg limit; cocoa Cd up to 1.8 mg/kg; shellfish Cd up to 4.8 mg/kg; Pb in tea/coffee/cocoa to 1.03 mg/kg. Most comprehensive multi-matrix TDS synthesis in corpus. Evidence tier: A. Metals: tAs, iAs, Cd, Pb. Matrices: rice-grain, cocoa-bean, shellfish, tea, coffee.

gupta2024-tilapia-heavy-metals-cauvery-india (FM_11598533) AAS, Cr, Cd, Pb, Ni in tilapia muscle/liver/gills, Cauvery River, Tamil Nadu (n=16). Liver Cd 34–62× permissible limit; cancer risk above USEPA threshold. Note: total Cr not speciated for Cr-VI — carcinogenic risk from Cr likely overstated. Evidence tier: A. Metals: Cd, Pb, Cr, Ni. Matrices: freshwater-fish. Jurisdictions: IN.

Group 2 (FM_11622546 – FM_11700321)

paz-suconota2024-mercury-fish-pastaza-ecuador (FM_11654945) ICP-MS, tHg in freshwater fish from Pastaza River, Ecuador, n=40, 13 fish families. tHg range 0.020–0.241 mg/kg ww; all below Codex/FAO/WHO limits. Carnivorous predators highest. Evidence tier: A. Metals: tHg. Matrices: freshwater-fish. Jurisdictions: EC.

barquero2024-mercury-bass-almaden-spain (FM_11666705) Critical find. tHg, MeHg, tAs, Pb, Sb in largemouth bass from Valdeazogues River transect through Almadén mercury mine district, Spain. tHg 0.47–7.61 mg/kg ww — highest ever recorded for this species globally. MeHg 79.7–92.1% of tHg (directly speciated). Sb (antimony) also measured. Evidence tier: A. Metals: tHg, MeHg, tAs, Pb, Sb. Matrices: freshwater-fish. Jurisdictions: ES.

tran2024-arsenic-cadmium-vietnamese-rice-qtl (FM_11666011) ICP-MS, tAs and Cd in brown and white rice grain from 184 Vietnamese rice landraces. tAs mean 0.16 ppm BR / 0.11 ppm WR; Cd mean 0.21 ppm both types. 27 GWAS QTL associations identified; strong heritability. Note: total As only, no iAs speciation. Evidence tier: A. Metals: tAs, Cd. Matrices: rice-grain. Jurisdictions: VN.

bruno2024-metals-mussels-clams-faro-lake-sicily (FM_11671395) ICP-MS, n=80 mussels + 80 clams from Sicilian shellfish farm (Faro Lake). As, Cd, Pb, Hg, Ni, Cr plus 10 additional elements. All Cd/Pb/Hg below EU Regulation 915/2023 limits. Total Cr elevated but not speciated. Evidence tier: A. Metals: tAs, Cd, Pb, tHg, Ni, Cr. Matrices: shellfish. Jurisdictions: IT.

najem2024-metals-common-carp-iraq (FM_11682752) FAAS, tAs/Pb/tHg in liver, gills, muscle of 10 common carp from Baqubah markets (Tigris River). tHg exceeds WHO limit (0.5 mg/kg) in 60% of liver, 100% of gill, 90% of muscle samples. Evidence tier: A. Metals: tAs, Pb, tHg. Matrices: freshwater-fish. Jurisdictions: IQ.

Group 3 (FM_11700680 – FM_11870952)

dai2024-chongqing-dietary-arsenic-exposure (FM_11839360) ICP-MS/HGAFS, n=4,900 food samples across 10 categories, Chongqing, 2018–2023. Rice mean 98 ppb tAs, P95 183 ppb. Monte Carlo dietary exposure model: carcinogenic MOE <100 for all populations; children 3–6 highest risk. Evidence tier: A. Metals: tAs. Matrices: rice-grain, multi-food. Jurisdictions: CN.

fuenteslopez2025-colombia-freshwater-fish-mercury (FM_11870952) Direct mercury analysis (USEPA 7473), n=326 carnivorous freshwater fish (9 species), gold-mining-impacted La Mojana, Colombia. Overall mean 0.31 µg/g ww; dry-season peak 0.54 µg/g (Cynopotamus magdalenae). HQ >1 for frequent consumers. Evidence tier: A. Metals: tHg. Matrices: freshwater-fish. Jurisdictions: CO.

Group 4 (FM_11872742 – FM_11996899)

gama2025-bvl-rice-trace-elements (FM_11876284) ICP-MS, n=5 rice grain samples (white Carolino 2020/2021/2022, wild, brown) from Baixo Vouga Lagunar, Portugal. tAs, Pb, U measured; all below EC limits. Small n limits synthesis use. Evidence tier: A. Metals: tAs, Pb, U. Matrices: rice-grain. Jurisdictions: PT.

brodziak-dopierala2024-hg-supplements-poland (FM_11872768) AAS, n=139 dietary supplements from Polish market. tHg median 2.0 µg/kg (supplements), 3.4 µg/kg (herbal); range 0.1–57.4 µg/kg. No samples exceeded regulatory limits. Evidence tier: A. Metals: tHg. Matrices: dietary-supplement. Jurisdictions: PL.

High-Value Finds

  1. zhao2024 — Global TDS synthesis across 25+ food categories: most comprehensive multi-matrix occurrence review in corpus. Critical for contamination_profile population estimates.

  2. barquero2024 — Almadén tHg 7.61 mg/kg ww in bass, MeHg directly speciated at 79–92% of tHg. Extreme endpoint for freshwater-fish mercury profile.

  3. alrashdi2024 — HPLC-ICP-MS speciated iAs in Saudi market rice. Adds Gulf region data to rice iAs geographic breakdown.

  4. li2024-rice-cadmium-governance-china — n=1.76M monitoring points, integrated governance achieves 57–78% Cd reduction. Evidence base for the “intervention works” side of rice Cd management.

Batch Commits

  • 519f81e — group 1: 5 pages, 42 FP
  • ff4abae — group 2: 5 pages, 45 FP (note: groups 2 and 3 committed separately)
  • 873fef7 — group 3: 2 pages, 48 FP
  • 6626ee3 — group 4: 2 pages, 48 FP