EFSA 2024 - Small organoarsenic species in food
EFSA’s 2024 CONTAM opinion is the current EU risk assessment for small organoarsenic species, especially dimethylarsinic acid DMA(V) and monomethylarsonic acid MMA(V), in food. It matters for the wiki because it separates total arsenic, inorganic arsenic, and methylated organic arsenic instead of treating all arsenic in rice, fish, shellfish, and seaweed as equivalent. EFSA found that DMA(V), not MMA(V), is the risk-driving small organoarsenic species under the available data: DMA(V) exposures produce margins of exposure below 10,000 in many dietary surveys, especially for high-percentile infants, toddlers, other children, fish consumers, rice consumers, and rice-based infant-formula scenarios. MMA(V) values can be high in oysters, mussels, smoked herring, canned herring, and some demersal fish scenarios, but EFSA’s calculated MOEs remained well above its low-concern threshold.
Key numbers
Hazard reference points and risk thresholds:
| Species | Critical endpoint | Reference point | EFSA low-concern MOE screen | EFSA conclusion |
|---|---|---|---|---|
| MMA(V) | Decreased body weight linked to diarrhoea in rats | BMDL10 = 18.2 mg MMA(V)/kg bw/day, equivalent to 9.7 mg As/kg bw/day | >= 500 | All modelled MOEs were above 500; no health concern identified |
| DMA(V) | Increased urinary bladder tumours in male rats | BMDL10 = 1.1 mg DMA(V)/kg bw/day, equivalent to 0.6 mg As/kg bw/day | >= 10,000 | Many MOEs below 10,000; EFSA says this raises a health concern |
| Other small organoarsenic species | Not resolved | No RP derived | Not assessed | Toxicology data insufficient |
Occurrence data scope:
| Data point | Value |
|---|---|
| DMA analytical results after cleaning | 1,260 |
| MMA analytical results after cleaning | 988 |
| DMA left-censored results | 44% |
| MMA left-censored results | 94% |
| Countries represented | 8 EU countries for DMA; 4 for MMA |
| Dominant sampling country | Italy, 67% of DMA samples and 85% of MMA samples |
| Sampling years used in occurrence data | Mostly 2012-2021; figure includes 2012-2022 distribution |
| Results with uncertain unit reporting | 654 DMA and 653 MMA results; EFSA assumed ug As/kg |
| Thio-analogue occurrence data submitted | None for thio-DMA(V), dithio-DMA(V), or thio-MMA(V) |
Selected DMA occurrence values used for exposure assessment, expressed as ug As/kg whole weight:
| Food / commodity | N | Left-censored | Mean LB-UB | High/reliable percentile noted |
|---|---|---|---|---|
| Grains and grain-based products, FoodEx2 level 1 | 533 | 15% | 30.4-33.1 | P95 75.7 |
| Vegetables and vegetable products, FoodEx2 level 1 | 174 | 38% | 127.2-133.2 | P95 387.3 |
| Fish/seafood/amphibians/reptiles/invertebrates, FoodEx2 level 1 | 227 | 41% | 58.4-62.9 | P95 not calculated; pooled category |
| Rice grain, polished | 221 | not stated in summary | 40.0 | LB=UB |
| Rice grain, brown | 110 | not stated in summary | 27.8 | LB=UB |
| Rice and similar | 439 | 4% | 33.5-34.1 | 79.2 |
| Rice flour | 441 | 4% | 39.3-40.0 | 89.4 |
| Puffed/extruded rice textured bread | 31 | 35% | 32.6-43.5 | 50.2 |
| Rice-based children biscuits/rusks/cookies identified as rice cakes | 7 | 29% | 22.1-25.2 | 23.5 |
| Algae/prokaryotes organisms | 116 | 9% | 143-145 | 449 |
| Algae/prokaryotes organisms, dried | 112 | 10% | 605-615 | 1,706 |
| Algae-based formulations | 19 | 84% | 104-118 | 0-20 |
| Seaweed-containing salads | 3 | 0% | 1,356 | Not reported |
| Marine fish | 34 | 71% | 36.5-45.0 | 12.0-20.0 |
| Diadromous fish | 19 | 42% | 4.9-10.3 | 10.0-10.9 |
| Freshwater fish | 7 | not stated in table row | No DMA found | Not reported |
| Molluscs | 102 | 24% | 63.0-66.9 | 170 |
| Canned/marinated/pickled seafood | 123 | 36% | 53.0-57.1 | 170 |
| Marinated/pickled fish | 5 | 0% | 83.7 | Not robust |
| Canned/jarred fish | 18 | 61% | 10.5-14.7 | Not robust |
Selected MMA occurrence values, expressed as ug As/kg:
| Food / commodity | N | Left-censored | Mean LB-UB | Notes |
|---|---|---|---|---|
| Fish/seafood/amphibians/reptiles/invertebrates, FoodEx2 level 1 | 152 | 53% | 46.3-53.4 | P95 251 |
| Grains and grain-based products, FoodEx2 level 1 | 463 | 100% | 0-6.0 | P95 0-20 |
| Rice samples submitted to EFSA | 411 | 100% | No quantified MMA | EFSA says this matches literature |
| Fish samples submitted to EFSA | 35 | 100% | No quantified MMA | Literature data used for fish scenarios |
| Oysters | 27 | 0% | 227 | EFSA occurrence data |
| Mussels | 48 | 46% | 54.0-61.5 | EFSA occurrence data |
| Unspecified molluscs | 99 | 44% | 88.6-95.6 | EFSA occurrence data |
| Miscellaneous demersal marine fish | 35 | not stated | 87.7 | Literature, CALIPSO/Leblanc 2006 |
| Mackerel | 20 | not stated | 78.0 | Literature, CALIPSO/Leblanc 2006 |
| Canned herring | 20 pooled samples | not stated | 152 | Literature, Hackethal et al. 2021 |
| Smoked herring | 20 pooled samples | not stated | 397 | Literature, Hackethal et al. 2021 |
| Canned mackerel | 1 composite | not stated | 82.0 | Literature, CALIPSO/Leblanc 2006 |
| Fish fingers, breaded | derived | not stated | 2.7 | From cod/hake/haddock data |
Dietary exposure and MOE results:
| Scenario | Exposure / MOE result |
|---|---|
| Highest chronic DMA exposure across European surveys | Toddlers: mean 0.130-0.157 ug As/kg bw/day; P95 0.397-0.477 |
| Adult chronic DMA exposure maxima | Mean 0.038-0.044 ug As/kg bw/day; P95 0.133-0.158 |
| Rice consumers only, highest DMA mean exposure | Other children: 0.076-0.078 ug As/kg bw/day |
| Rice consumers only, highest DMA P95 exposure | Other children: 0.186-0.190 ug As/kg bw/day |
| Fish-meat consumers only, highest DMA mean exposure | Toddlers: 0.165-0.205 ug As/kg bw/day |
| Fish-meat consumers only, highest DMA P95 exposure | Toddlers: 0.415-0.511 ug As/kg bw/day |
| Rice-based infant formula, average DMA level and high consumption | 0.25 ug As/kg bw/day |
| Rice-based infant formula, maximum DMA level and high consumption | 0.62 ug As/kg bw/day |
| DMA MOE range, mean chronic exposure | 150,000 to 3,800 |
| DMA MOE range, P95 chronic exposure | 35,300 to 1,300 |
| Rice-based infant formula DMA MOEs | 3,200, 2,400, 1,250, and 970 across the four scenarios |
| MMA fish-meat consumers MOEs | 3,233,000 down to 28,000 |
| MMA mollusc consumers MOEs | 9,700,000 down to 52,000 |
| MMA processed/preserved fish consumers MOEs | 9,700,000 down to 28,000 |
| Probability DMA MOE < 10,000, chronic P95 exposure | Infants 0.65, toddlers 0.72, other children 0.59 |
| Probability DMA MOE < 10,000, rice-based infant formula | 0.98 for mean scenario and 1.0 for high scenario |
| Probability DMA MOE < 10,000, fish consumers P95 | Infants 0.59, toddlers 0.61, other children 0.53 |
Main contributors to DMA dietary exposure:
| Population group | Notable contributors |
|---|---|
| Infants | Fish meat 3-78% (median 13%); reconstituted infant cereals 0-72% (median 33%) |
| Toddlers | Fish meat 14-77% (median 29%); rice 11-65% (median 29%) |
| Other children | Rice 17-72% (median 43%); fish meat 16-61% (median 30%) |
| Adults / elderly / very elderly | Fish meat and rice dominate; fish-meat contribution in very elderly up to 92% (median 47%) |
| Adult subgroups | Dried/smoked/salted fish up to 27% in elderly; molluscs up to 36% in adults |
Methods (brief)
EFSA combined a public-literature review, cleaned occurrence submissions, EFSA Comprehensive European Food Consumption Database surveys, and specific consumers-only scenarios. All occurrence values used for exposure assessment were converted to ug As/kg whole weight. EFSA assumed reported DMA and MMA were the pentavalent species DMA(V) and MMA(V) when providers did not confirm valency, and assumed ug As/kg where unit reporting did not specify whether values were elemental arsenic or species mass. Chronic DMA exposure used 49 dietary surveys from 22 European countries; MMA exposure focused on consumers-only scenarios because nearly all submitted MMA data outside molluscs were left-censored. Occurrence values for some processed commodities were derived from raw primary commodities with EFSA Raw Primary Commodity processing factors and recipes, assuming no DMA loss during processing.
Implications
This source supports arsenic-speciation pages and downstream rows where total arsenic can be misleading: rice and rice products, rice-based infant foods, fish, shellfish, canned/preserved fish, seaweed/kelp foods, algae-based supplements, and rice-based formula-like products. The DMA(V) results are especially important because organic arsenic is often treated as lower concern, yet EFSA’s DMA(V) MOEs fall below 10,000 in many high-exposure scenarios. For rice and seafood matrices, this source should be used alongside inorganic-arsenic sources rather than merged into them: DMA/MMA are not iAs, but they are also not toxicologically irrelevant.
The infant-formula relevance is narrow and should remain visibly qualified. EFSA’s rice-based infant-formula scenario used hydrolysed-rice formula powder data and default infant intake assumptions; it is not evidence for cow-milk formula or soy formula unless the destination page explicitly treats the rice-based product as specialty/dairy-free context.
Wiki pages this source may touch
- arsenic
- arsenic-total
- arsenic-inorganic
- rice
- rice-flour
- rice-cakes
- rice-milk
- infant-formula
- cereal-based-infant-formula
- fish
- seafood
- shellfish
- molluscs
- seaweed
- tinned-fish
- fish-fingers
- rice-bulk-grain
- rice-snacks-crackers
- teething-and-snacks-rice-based
- baby-cereals-dry-rice-based
- rice-noodles
- rice-beverages-rice-milk
- infant-formula-dairy-free
- fish-marine-predatory
- fish-marine-non-predatory
- fish-freshwater
- shellfish
- canned-fish
- canned-seafood
- seaweed-kelp-foods
- supplements-algae-seaweed-based
Verification notes
- Read the PDF text across the full opinion, with close checks on the summary, occurrence sections 3.6.1-3.6.2, exposure sections 3.7.1-3.7.2, risk-characterisation sections 3.8.1-3.8.2, uncertainty section 3.9.2, conclusions 4.11-4.15, and recommendations.
- DOI verified from the PDF title page as
10.2903/j.efsa.2024.8844; no matching source page or DOI record was found before ingest. - EFSA reports DMA/MMA occurrence as elemental arsenic concentration (
ug As/kg) for exposure assessment. Do not reinterpret these as ug DMA/kg or ug MMA/kg. - The source uses assumptions that should travel with extracted values: 654 DMA and 653 MMA results had uncertain species-mass versus elemental-arsenic unit reporting; EFSA assumed
ug As/kg. EFSA also assumed DMA/MMA were pentavalent species when valency was not confirmed. - Thio-DMA(V), dithio-DMA(V), thio-MMA(V), DMA(III), and MMA(III) are important data gaps here, not routeable occurrence findings from the submitted EFSA dataset.
- Brand names do not appear in this source page. Instrument/software names are omitted because the page is not about validating a specific analytical method.
Page history
The five most recent substantive edits to this page. 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.