4 Fisheries Administration, Phnom Penh 120101, Cambodia; chhounchamnan@gmail.com (C.C.);

Overview

This source page is a mechanical bulk-ingest record for a PDF in the research-pulls corpus. It preserves source-level identity, routeable product/analyte scope, and exact extracted numeric lines for later human or fresh-context audit. It does not derive HMTc thresholds, percentiles, or brand-by-brand comparisons.

Key numbers

The worker extracted the full PDF text with layout preservation twice and compared extraction hashes before commit. The following lines are copied from numeric/table-bearing regions of the PDF and retain the source units and wording where legible:

Fidero, K.; et al. Chemical Hazards in mean concentration of 1.92 mg/kg. The pooled geometric means of arsenic and mercury in fish
from Benin found the highest concentration of PAH4 at 0.48 ± 0.31 mg/kg in smoked
ated dietary MeHg source in Asia, projecting approximately a 60% rise in concentrations
Table 1. List of certain carcinogenic chemicals that can be found in products of animal origin.
of cadmium and mercury as 2.5 and 4 µg/kg body weight, respectively. The results
2000 to 2024, reported by 23 studies included in the review, was summarized in Table 2.
Table 2. Quality assessment criteria for full-text review.
elemental toxins, specifically arsenic, cadmium, lead, and mercury. Meanwhile, 11 studies
The pooled geometric mean arsenic concentration in fish was 0.40 mg/kg (95% CI:
0.25–0.66). The 95% prediction interval ranged from 0.015 to 10.50 mg/kg, indicating
The average mercury level in fish is ~0.14 mg/kg (95% CI: 0.087 to 0.223), significantly
above zero, and it serves as a meaningful finding for risk or regulation. Large τ2 suggesting
large between-study variance (log scale) and high I2 95% of the total variability is between
Most studies carry ~3% weight, indicating a balanced sample. No single study dominates
were outlined in Table 3. The concentrations of each identified chemical hazard in the food
CAC and the EU was also included in Table 4.
Table 3. Summary of evidence of chemical hazards in products of animal origin in Cambodia from
Table 4. Evidence of concentration of chemical contaminants in different POAO in Cambodia from
mean arsenic concentration in fish was 0.40 mg/kg (95% CI: 0.25–0.66). Details of meta
in Table 4. Despite the maximum limits of arsenic in other products such as rice and salt,
established the maximum level of cadmium in fish as 0.05 mg/kg. Our review indicates
revealed the pooled estimate of average mercury in fish is ~0.14 mg/kg (95% CI: 0.087 to
0.223). The concentrations of mercury in mg/kg for beef, beef viscera, eggs, and pork are
summarized in Table 4. In total, 1.75% of the samples tested for mercury did not meet the
standards established by the CAC, which allows a maximum concentration of 0.005 mg/kg,
while all samples (100%) surpassed the EU’s permissible limit of 0.002 mg/kg.
concentration of 4.05 mg/kg. Neither the CAC nor the EU has any specific limits for the
butyl tin (expressed in wet weight) varied between 0.0024 and 0.15 mg/kg, with an average
concentration of 0.027 mg/kg. Similarly, the levels of tri-butyl tin in the marine fish samples
provinces (Table 5). For testing the samples, USEPA methods 3620B and 3640 A were
Table 5. Evidence of PBDE and organochlorine pesticides in marine fish and mussels.
concentration of chloramphenicol in farmed fish ranged from 0.03 to 1.18 mg/kg, with an
average concentration of 0.255 mg/kg. In total, 23 out of 129 samples tested did not comply
banned substances like nitrofuran metabolites (0.19 mg/kg in Kampong Chhnang and
0.14 mg/kg in Takeo province) and leuco-malachite green 1.46 mg/kg in Kandal province.
of phthalate esters in beef, beef viscera, fish, and pork is summarized in Table 4. Neither the
As shown in Table 6, none of the hazard index of the average chemical toxin con-
Table 6. Health risk assessment of exposure to cadmium and mercury contamination in POAO
indicates that the highest arsenic concentration found in freshwater fish was 10.7 mg/kg,
13.1 to 22.2 mg/kg as reported in Thailand (61). Arsenic dietary intake primarily derives
these, lead was responsible for 54% of the cases, methylmercury accounted for 22%, arsenic
contributed to 20%, and cadmium was linked to 1%. Notably, arsenic was the leading

Methods (brief)

and type of chemical contaminant, concentration details (including total sample counts,
total number of samples exceeded the maximum residue limits set by the CAC and the EU.
Most studies carry ~3% weight, indicating a balanced sample. No single study dominates
Additionally, the total number of samples, testing methodologies, and equipment utilized
Arsenic (Inorganic Kampong Cham, Aquaculture site Acid digestion, HPLC-ICP-MS,
arsenic and Kandal, Kratie, Tonle and nature (lakes, 331 internal ICP-MS,
total arsenic) Sap ponds, rivers) procedures ICP-OES, ETAAS
products Kampong Chhnang, and markets HPLC-FLD
Fish and fishery Tonle Sap, Phnom Acid digestion
Cadmium Coastal water 208 ICP-MS, ETAAS 9, 10, 14, 18
Lead Fish 249 Acid digestion ICP-MS
Chhnang, Pursat, Coastal water, AAS, Direct 7, 9, 10, 12, 19,
Kampong Thom, Siem markets ICP-MS 1, 2,3,4
aromatic Smoked Market, HPLC-FLD,
aromatic Mussels, smoked Kampong Cham, >87 samples; instead,
Lead Freshwater fish <LOD 0.31 0.05 5.88 5.88
including beef, beef viscera, egg, fish, and pork. Under the group of elements, 1283 samples
Materials S1) (31–35,37,47). The 331 samples were taken from snails, clams, fish, beef, beef

Implications

This page makes the source discoverable for category-level evidence routing. Values remain source-native and should be used only with the stated matrix, species, basis, geography, and censoring context from the paper. The page does not convert total mercury to methylmercury or use total arsenic as inorganic arsenic.

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Verification notes

Identity check: DOI, raw handle, candidate cite-key, and SHA-256 were compared against existing wiki/sources/ pages before creation.
Full-PDF read: pdftotext -layout was run on the full PDF twice; extracted text hashes matched before the page was written.
Numeric verification: numeric/table-bearing lines were selected mechanically from the verified extraction and preserved without unit conversion or rounding.
Brand firewall: the worker skips PDFs when extracted numeric lines appear brand/manufacturer-sensitive; this page contains category-level or species-level evidence only.
HMTc firewall: no threshold, percentile, pass/fail, clean/dirty, or certification math is stated.

Update history

The five most recent substantive edits to this page, classified major (evidence or structure moved), correction (a published value or statement was wrong and has been fixed), or minor (narrative rewritten without changing the underlying evidence). Each description is derived from what the edit did to this page; the linked commit is the authoritative record, routine regeneration passes are excluded, and the full version history lives in git. When DOI minting comes online (see schema docs), each entry below will also link to a version-pinned DataCite DOI.

Commit	Date	Change	Description
b01ec52c	2026-08-04	major	2 sections added
d49e450f	2026-08-03	major	5 sections added; narrative text revised