General Standard for Contaminants and Toxins in Food and Feed (CXS 193-1995)

Summary

Codex Standard CXS 193-1995 is the international Codex Alimentarius General Standard for Contaminants and Toxins in Food and Feed, the operative international standard from which national food-safety regulators in many jurisdictions derive their domestic maximum levels. The standard sets matrix-specific maximum levels for cadmium, lead, mercury, methylmercury, inorganic arsenic, tin, marine biotoxins, mycotoxins, and other contaminants. Cadmium MLs span 22 matrix categories from 0.003 mg/kg in natural mineral waters to 2.0 mg/kg in 100 percent cocoa powder. Lead MLs are the second-most-extensive in the standard, spanning 30+ matrix categories. The standard is amended periodically through the Codex Committee on Contaminants in Foods process; the 17th Session (April 2024) added the new quinoa cadmium ML at 0.15 mg/kg, which is reflected in the current standard.

Key numbers — Cadmium MLs

JECFA reference: 16 (1972), 33 (1988), 41 (1993), 55 (2000), 61 (2003), 64 (2005), 73 (2010), 77 (2013), 91 (2021). The 73rd meeting established the operative provisional tolerable monthly intake (PTMI) of 25 µg/kg b.w./month.

Toxicological guidance value: PTMI of 25 µg cadmium (Cd)/kg body weight per month, established at JECFA’s 73rd meeting (2010), reflecting the long half-life of cadmium in humans.

Contaminant definition: Cadmium, total.

Related codes of practice: CXC 49-2001 (Source-directed measures), CXC 81-2022 (Cadmium in cocoa beans).

Key numbers — Lead MLs (selected)

JECFA reference: 10 (1966), 16 (1972), 22 (1978), 30 (1986), 41 (1993), 53 (1999), 73 (2010). At the 73rd meeting (2010), JECFA estimated that the previously established PTWI of 25 µg/kg b.w. is associated with a decrease of at least three intelligence quotient (IQ) points in children and an increase in systolic blood pressure of approximately 3 mmHg (0.4 kPa) in adults; the Committee concluded the PTWI could no longer be considered health-protective and withdrew it.

Contaminant definition: Lead, total.

Related codes of practice: CXC 56-2004 (Prevention and reduction of lead contamination in foods), CXC 49-2001.

(The lead (Pb) ML table extends through additional matrices including salt, processed cereals, wine, juices for special use; the entries above cover the most-cited and policy-consequential matrices.)

Key numbers — Arsenic MLs

JECFA reference: 5 (1960), 10 (1967), 27 (1983), 33 (1988). At JECFA 33 (1988), the Committee established the PTWI for inorganic arsenic at 0.015 mg/kg b.w.; this value was subsequently withdrawn by JECFA 72 (2010) as no longer health-protective, with the BMDL01 of 3.0 µg/kg b.w./day (range 2–7) identified for a 0.5% increased incidence of lung cancer, but the standard’s Arsenic schedule retains the 1988 PTWI as the cited toxicological-guidance value for its 2009 amendments.

Residue definition: arsenic, total (As-tot) when not otherwise mentioned; inorganic arsenic (As-in); or other specification.

Related code of practice: CXC 49-2001 (Source-directed measures).

The Arsenic schedule in CXS 193 is narrow relative to Cd and Pb; the MLs concentrate on fats/oils, salt, and water rather than on plant or animal matrices (the inorganic arsenic (iAs) in rice schedule for polished rice is established under CXS 193 via the CCCF8 2014 amendment, with subsequent amendments for husked rice and rice-based products; the 2009 snapshot does not contain the iAs in rice MLs).

The 2009 snapshot’s Arsenic schedule expresses MLs as total arsenic (As-tot) by default, with PTWI calibrated against inorganic arsenic. The subsequent CCCF rice iAs MLs were the first Codex MLs expressed as inorganic arsenic specifically and reflect the JECFA 72 (2010) update placing iAs as the primary toxicologically relevant species.

Key numbers — Mercury and methylmercury MLs

Mercury (total): PTWI 0.005 mg/kg b.w. (JECFA 22, 1978). Contaminant definition: mercury, total.

Methylmercury: PTWI 0.0016 mg/kg b.w. (JECFA 61, 2003). Contaminant definition: methylmercury.

Methylmercury values are Codex guideline levels (GL), not maximum levels (ML); they are not legally binding but inform jurisdictional thresholds.

Key numbers — Tin (Sn) MLs

Tin (Sn): PTWI 14 mg/kg b.w. (JECFA 26, 1988; maintained 2000). Contaminant definition: tin, total (Sn-tot) unless otherwise specified; includes tin from food-additive uses.

Related codes of practice: CXC 60-2005 (Inorganic tin in canned foods), CXC 49-2001.

The Sn schedule is concentrated on canned goods (where tin migration from tinplate is the contamination pathway). Suffix C denotes “in canned products only.”

The canned meats are the only Codex matrices with a paired tinplate-vs-other-container split: tin migration from tinplate justifies a higher canned-product ML (200 mg/kg) than the same product in non-tinplate containers (50 mg/kg).

Snapshot context

This source page synthesizes Codex CXS 193-1995 inclusive of CCCF amendments through CCCF17 (April 2024), which is the form in which the standard is most often cited in current regulatory and certification work. The PDF at raw_path is the 2009-amended snapshot (footer: “Adopted 1995; Revised 1997, 2006, 2008, 2009; Amended 2009”); its hash is recorded for archival reproducibility. The 2009 snapshot is the operative reference for the Sn MLs and the methylmercury GLs (these have not been substantively amended since), and for the Cd PTWI of 0.007 mg/kg b.w. that was the operative toxicological reference value before JECFA 73 (2010) replaced it with the PTMI of 25 µg/kg b.w. per month.

Toxicological reference values — deltas

• Cd: PTWI 0.007 mg/kg b.w. (2009 snapshot, JECFA 64 2005) → PTMI 25 µg/kg b.w./month (JECFA 73 2010, withdrew the PTWI). Current page reflects PTMI.
• Pb: PTWI 0.025 mg/kg b.w. (2009 snapshot, JECFA 53 1999) → PTWI withdrawn at JECFA 73 (2010). Current page reflects withdrawal.
• arsenic (As): PTWI 0.015 mg/kg b.w. for iAs (2009 snapshot, JECFA 33 1988) → withdrawn at JECFA 72 (2010); BMDL01 3.0 µg/kg b.w./day for 0.5% increased lung cancer incidence is the current toxicologically-anchored value. Current page reflects withdrawal.
• mercury (Hg) total, methylmercury (MeHg), Sn: unchanged from 2009 snapshot.

Cd-side ML deltas (2009 snapshot → current)

• Quinoa: 0.15 mg/kg ML added at CCCF17 (2024). Not in 2009 snapshot.
• Chocolate by cocoa-solids percentage: 0.3 (<30%), 0.7 (30–50%), 0.8 (50–<70%), 0.9 (≥70%) — all added via CCCF11–13 (2017–2019). Not in 2009 snapshot.
• Cocoa powder (100% cocoa solids, dry matter basis): 2.0 mg/kg added at CCCF13 (2019). Not in 2009 snapshot.
• All Cd MLs for vegetable categories (brassica/bulb/fruiting/leafy/legume/pulses/root-and-tuber/stalk-and-stem), rice polished, wheat, marine bivalve molluscs, cephalopods, natural mineral waters, and salt food grade are unchanged between the 2009 snapshot and current standard.

Pb-side ML deltas (2009 snapshot → current)

The Pb schedule was substantively tightened across many matrices via CCCF11–CCCF17 amendments. Where wiki value differs from PDF value, the wiki value reflects current standard:

• Berries and other small fruits: 0.2 (2009) → 0.1 mg/kg (current, with cranberry/currant/elderberry split out at 0.2 each).
• Cranberry, currants, elderberry: added at 0.2 mg/kg each (CCCF amendments).
• Fruiting vegetables, other than cucurbits: 0.1 (2009) → 0.05 mg/kg (current, excluding fungi and mushrooms).
• Fresh farmed mushrooms (Agaricus, shiitake, oyster): 0.3 mg/kg added (CCCF amendments).
• Legume vegetables: 0.2 (2009) → 0.1 mg/kg (current).
• Pulses: 0.2 (2009) → 0.1 mg/kg (current).
• Canned fruits (generic): individual canned-fruit MLs at 1 mg/kg in the 2009 snapshot (canned fruit cocktail, grapefruit, mandarin oranges, mangoes, pineapple, raspberries, strawberries, tropical fruit salad — each at 1) → generic canned fruits ML 0.1 mg/kg (current).
• Jams (fruit preserves), jellies, marmalades: 1 (2009, jams and jellies only) → 0.4 mg/kg (current, with marmalades added).
• Mango chutney: 1 (2009) → 0.4 mg/kg (current).
• Table olives: 1 (2009) → 0.4 mg/kg (current).
• Canned vegetables (generic): individual canned-vegetable MLs at 1 mg/kg in the 2009 snapshot (asparagus, carrots, green beans/wax beans, green peas, mature processed peas, mushrooms, palmito, sweet corn, tomatoes — each at 1) → generic canned vegetables ML 0.1 mg/kg (current).
• Preserved tomatoes: 0.05 mg/kg added (current; the 2009 snapshot had Canned tomatoes 1 and Processed tomato concentrates 1.5 with no “Preserved tomatoes” row).
• Pickled cucumbers: 1 (2009) → 0.1 mg/kg (current).
• Canned chestnuts and chestnut puree: 1 (2009) → 0.05 mg/kg (current).
• Fruit juices: 0.05 mg/kg ready-to-drink including nectars (2009) → 0.03 mg/kg (current, excluding juices exclusively from berries; applies to juices for infants and young children).
• Fruit juices exclusively from berries and small fruits: 0.05 mg/kg added (current).
• Grape juice: 0.04 mg/kg added (current).
• Cereal-based foods for infants and young children: 0.02 mg/kg added (current).
• Infant formula and follow-up formula: 0.02 mg/kg ready-to-use (2009) → 0.01 mg/kg as-consumed (current).
• Ready-to-eat meals for infants and young children: 0.02 mg/kg added (current).
• Quinoa: 0.2 mg/kg Pb ML added (current; not in 2009 snapshot).
• Cattle edible offal: 0.5 (2009) → 0.2 mg/kg (current).
• Pig edible offal: 0.5 (2009) → 0.15 mg/kg (current).
• Poultry edible offal: 0.5 (2009) → 0.1 mg/kg (current).
• Edible fats and oils: 0.1 (2009) → 0.08 mg/kg (current).
• Fat spreads and blended spreads: 0.04 mg/kg added (current).

Pb MLs unchanged between the 2009 snapshot and current standard: brassica vegetables, bulb vegetables, fruiting vegetables (cucurbits), leafy vegetables, root and tuber vegetables (including peeled potatoes), cereal grains, meat of cattle/pigs/sheep, poultry meat, fish, milks, natural mineral waters, salt food grade, wine, vegetable oils, named animal fats, olive oil.

Sn, Hg, MeHg, As

All Sn MLs, Hg MLs, MeHg GLs, and the 2009 snapshot’s As MLs (fats/oils, mineral waters, salt) are substantively unchanged between the 2009 snapshot and the current standard. The iAs in rice MLs (polished 0.2; husked 0.35) were added at CCCF8–CCCF9 (2014–2015) and are not in the 2009 snapshot.

Provenance notes

License public-redistribute. Codex Alimentarius standards are released by FAO/WHO under terms permitting reproduction with attribution; the standard is freely accessible on FAO’s website at the canonical URL. The page was initially populated on 2026-04-25 from the FAO Codex web service via WebFetch. The 2009-amended PDF (raw_path, SHA-256 5adf44c2...8534dc) was archived on 2026-06-02 from the source-retrieval corruption-issue recovery batch and serves as the primary-source anchor for the values that are unchanged between the 2009 snapshot and the current standard (see Snapshot context). For values that were amended by CCCF11–CCCF17 (2017–2024), the canonical FAO web copy of CXS 193-1995 in its current form is the primary source; the agency URL is recorded above.

The standard is periodically amended. The values in this source page reflect the standard inclusive of CCCF17 2024 amendments (notably the new quinoa Cd ML of 0.15 mg/kg and the new quinoa Pb ML of 0.2 mg/kg, both reflected in the current standard).

Implications

• Certification: this standard is the international anchor for matrix-specific Cd and Pb MLs. Codex MLs are minimum harmonized values; many national jurisdictions (EU under Regulation 2023/915, US FDA via CTZ, China via GB 2762) set domestic MLs equal to or tighter than Codex. The values here form a literature-baseline reference; HMT&C threshold decisions that diverge from these MLs are recorded in HMT&C-side rationale documentation per the wiki/HMT&C firewall.
• Courses: the multi-matrix structure of CXS 193 (with separate MLs for cocoa powder vs chocolate by cocoa-solid percentage, for offal by species, for infant foods at age-specific tighter levels) is a teachable model of contaminant-management standardization.
• App: every commodity-by-commodity ML in this standard is a candidate app benchmark. Commonly-referenced examples include the cocoa powder Cd ML of 2.0 mg/kg, dark chocolate (≥70 percent solids) Cd ML of 0.9 mg/kg, polished rice Cd ML of 0.4 mg/kg, leafy vegetables Cd ML of 0.2 mg/kg, infant formula Pb ML of 0.01 mg/kg, and infant cereal-based foods Pb ML of 0.02 mg/kg.

Related evidence

• Cadmium
• Lead
• Codex Alimentarius — Maximum Levels for Cadmium in Food
• Rice
• Wheat
• Cocoa
• Chocolate
• Spinach
• Potatoes
• Organ Meats (Kidney and Liver)
• Molluscs
• Wild Mushrooms
• Quinoa

Update history

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