Begday et al. 2026 — Heavy metals in plant-milk alternatives on the Russian market

Begday and colleagues at North-Caucasus Federal University in Stavropol’ measured lead, cadmium, zinc, and copper in eight plant-based milk beverages distributed in or producible from Russian-market raw materials: four commercial ready-to-drink beverages (one almond, one rice, one coconut, one oat) purchased at a Russian retail chain, and four laboratory-prepared beverages produced from mature buckwheat groats, green buckwheat groats, oat flakes, and long-grain rice via a standardized soak-and-filter protocol. All eight samples fell well below Russian SanPiN 42-123-4089-86 maximum permissible concentrations (MPCs) for the four metals, with the highest reported value (lead at 0.053 mg/kg in mature-buckwheat-groat milk) reaching only 10.6 percent of the 0.5 mg/kg lead MPC. Cadmium was non-detected in all four laboratory-prepared samples but was quantified in all four commercial beverages (0.0068 to 0.0108 mg/kg). The authors computed hazard quotients (HQ) for adults (70 kg, 120 kg beverage/year) and children (31 kg, 137.4 kg beverage/year) against EPA 2021 reference doses; per-metal HQs ranged from 0.000004 to 0.00874 and total HQ sums per beverage ranged from 0.00061 to 0.0062, all well below the threshold of 1 that would indicate non-carcinogenic concern.

Key numbers

All concentrations below are in milligrams per kilogram (mg/kg) of the beverage as analyzed and as consumed; the authors report a single basis throughout and do not distinguish wet versus dry weight. Values are arithmetic means of two parallel determinations rounded to four decimal places, per the source’s Materials and Methods. “n.d.” denotes non-detect (below the source’s reported detection limit calculated as 3 Sn / (p√n)).

Concentration by sample (Table 1, source p. 63)

The authors report that across all eight samples, concentrations remained within 4.8 to 36.7 percent of the corresponding MPC depending on metal and sample. Specifically: maximum Pb of 0.0530 mg/kg (mature buckwheat-groat milk) is 10.6 percent of the 0.5 mg/kg MPC; maximum Cd of 0.0108 mg/kg (commercial coconut beverage) is 36.0 percent of the 0.03 mg/kg MPC; maximum Zn of 0.4409 mg/kg (green buckwheat-groat milk) is 14.7 percent of the 3 mg/kg MPC; maximum Cu of 0.0233 mg/kg (oat-flake milk) is 0.23 percent of the 10 mg/kg MPC. The authors highlight three cross-sample trends: zinc consistently highest in green buckwheat (0.4409 mg/kg); copper at moderate levels (0.0097 to 0.0233 mg/kg) across lab-prepared samples; cadmium below detection in every laboratory-prepared sample but detectable in every commercial sample.

Hazard quotients for commercial samples (Table 2, source p. 64)

Hazard quotients for laboratory-prepared samples (Table 3, source p. 65)

Cadmium HQ rows are absent from Table 3 for all four laboratory-prepared samples because Cd was non-detected. The authors note the maximum HQ across all eight samples is 0.00874 (cadmium, child consumer of commercial coconut beverage); every per-metal HQ and every total HQ sum sits at least two orders of magnitude below the HQ = 1 threshold that would indicate non-carcinogenic concern under the Russian R 2.1.10.1920-04 health risk assessment guidance.

Exposure assumptions used in the HQ calculation

The hazard quotient is HQi = Di ÷ RfD, where Di = (Ci × M × Tp) / (P × T) and Ci is the measured concentration, M is the annual beverage consumption, Tp is exposure duration in years, P is body weight, and T is the averaging time. The authors use: adult P = 70 kg, M = 120 kg/year; child P = 31 kg, M = 137.4 kg/year; Tp = 1 year for both; T = 30 years for both. EPA 2021 reference doses applied: Pb 0.0035 mg/kg/day, Cd 0.0005 mg/kg/day, Cu 0.04 mg/kg/day, Zn 0.3 mg/kg/day. MPCs taken from SanPiN 42-123-4089-86.

Methods (brief)

Sample preparation followed GOST 26929-94 microwave-assisted acid mineralization. Concentrations were quantified by atomic absorption spectrometry (AAS) on a Thermo Scientific iCE 3300 instrument. Results were expressed in mg/kg and compared against the Russian SanPiN 42-123-4089-86 maximum permissible concentrations for toxic elements in foodstuffs. Each sample was measured in two parallel determinations; results were averaged and rounded to two decimal places (Table 1 values appear to four decimals after author rounding from intermediate calculations). The authors did not perform speciation; all reported values are total lead, total cadmium, total zinc, and total copper. The reported detection-limit treatment follows m_max < (3 Sn × Y × K) / (p × √n), where Sn is the residual standard deviation, Y is the original solution volume, K is the dilution coefficient, p is the sample mass, and n is the number of parallel absorbance measurements. The four laboratory-prepared beverages were produced per Russian patent No. 2756071: 100 g of cereal raw material soaked in 500 mL water for 8 hours at 20 ± 2 °C, then ground and filtered through double cheesecloth; the resulting beverage was analyzed the same day. Statistical comparison between commercial and laboratory-prepared samples is descriptive only; no formal hypothesis test is reported.

Implications

Certification: This is a Russian-market plant-beverage survey with n = 1 per botanical type for commercial samples (almond, rice, coconut, oat) and n = 1 per cereal raw material for laboratory-prepared samples (mature buckwheat, green buckwheat, oat flakes, long-grain rice), peer-reviewed in Izvestiya KGTU. It is direct evidence for plant-milk beverages on the Russian retail market in 2025-2026 against Russian SanPiN 42-123-4089-86 MPCs; it is not direct evidence against EU 2023/915, Codex, or FDA Closer to Zero thresholds because the authors do not compare to those frameworks. The very small per-product-type sample size (n = 1 per commercial brand category) limits the value of any single reported concentration as a population estimator. The strongest cross-cutting finding is the cadmium contrast between commercial and laboratory-prepared samples: detectable Cd (0.0068 to 0.0108 mg/kg) in all four commercial beverages, non-detect in all four laboratory-prepared beverages from the same nominal botanical category (rice in particular). The authors attribute this to commercial supply-chain factors and raw material origin but do not test that hypothesis directly.

App: Route to plant-milk, rice-milk, almond, coconut, oat, rice, and non-rice-grains (buckwheat) ingredient pages, and to plant-milks-non-soy-non-rice, plant-milks-rice-based, and rice-beverages-rice-milk product pages, and to lead and cadmium metal pages. The single-sample-per-botanical structure means these values function as plausibility anchors rather than centrals for population pooling; downstream pooling should treat each row as a single observation, not as a percentile estimate.

Courses: Useful for illustrating (a) the structural difference between commercial supply-chain plant beverages and home/laboratory-prepared analogues from the same raw material category, (b) how Russian-jurisdiction MPCs compare in magnitude to other regional frameworks for plant beverages, (c) the hazard-quotient framework for non-carcinogenic risk assessment of low-level food contamination, and (d) the role of cereal-raw-material agronomy (Pb in mature buckwheat groats accumulating from soil) in shaping the contamination profile of the derived beverage.

Wiki pages this source may touch

• plant-milk
• rice-milk
• almond
• coconut
• oat
• rice
• non-rice-grains
• plant-milks-non-soy-non-rice
• plant-milks-rice-based
• rice-beverages-rice-milk
• lead
• cadmium
• zinc
• copper

Verification notes

The source paper is in Russian with an English-language abstract, keywords, table captions, author affiliations, and full references list. All numerical data extracted to this page were read from the bilingual table captions (Tables 1, 2, 3) and the Russian Results section text, cross-checked against the English abstract’s summary statements. The Cyrillic-only narrative sections were translated for context; no numerical values were drawn from translation, only from the bilingual tables.

The commercial samples are reported in the source under Russian-language brand names: «Овсяша» (almond and coconut), «Здоровое меню» (rice), and «Nemoloko» (oat), all purchased at the «Перекресток» supermarket chain. Per CLAUDE.md Part 12 brand-firewall strict reading (locked 2026-05-17), this page reports each commercial sample by product-form descriptor only (“commercial almond beverage (Russian retail)” etc.) and does not name the brands. The single-brand-per-product-type structure of the source’s commercial sampling means the product type is the natural descriptor; this is not a brand-by-brand ranking situation (which would be a Part 12 violation) but a brand-attributed single-observation situation (which is converted to a product-form description without information loss for wiki purposes).

The laboratory-prepared samples used Russian-brand grain inputs («Националь» Hercules oat flakes, «Увелка» green buckwheat groats sort 1 and mature buckwheat groats sort 1, «Бакалейный стандарт» long-grain rice sort 2). These are raw-material grain brands feeding a lab preparation, not branded beverages, and are likewise reported on this page by grain-form descriptor only (“oat flakes,” “green buckwheat groats,” “mature buckwheat groats,” “long-grain rice”) without brand attribution. The source notes all grain inputs carried GOST certification and “without GMO” labeling.

The source reports the lead value for mature-buckwheat-groat milk at 0.0530 mg/kg, which the Russian Results text rounds to “0.053 mg/kg = 10.6 percent of MPC”; the abstract’s percentage range statement of 4.8 to 36.7 percent encompasses this and the cadmium maximum (36.0 percent for commercial coconut beverage). This page preserves the four-decimal table values throughout. The HQ values in Tables 2 and 3 are reported by the source at mixed precision (some to two significant figures, some to three, some to four); this page preserves the source’s reported precision verbatim per row.

The source reports a single basis (“mg/kg of product”) without explicitly labeling whether this is wet-weight (as-consumed liquid) or dry-weight; the laboratory preparation protocol (100 g grain to 500 mL water producing a beverage analyzed the same day) and the comparison to a 1:6 dilution-equivalent for retail beverages strongly suggest as-consumed liquid weight, consistent with how Russian SanPiN MPCs for “foodstuffs” are typically applied. Downstream pooling that requires explicit basis labeling should treat this as as-consumed liquid pending clarification.

The source’s MPC reference (SanPiN 42-123-4089-86, “Predel’no dopustimyye kontsentratsii tyazhelykh metallov i mysh’yaka v prodovol’stvennom syr’ye i pishchevykh produktakh”) is a Soviet-era 1986 sanitary regulation that remains in force in the Russian Federation for these analytes. No corresponding wiki regulation page exists at the time of ingest; future synthesis touching Russian-jurisdiction plant beverages may warrant a regulations/ru-sanpin-42-123-4089-86-heavy-metals.md page (Karen’s Step 0 Lock if added).

The four commercial samples represent four different product botanical categories (almond, rice, coconut, oat); within-category replication is n = 1 per botanical, which constrains the source to plausibility-anchor evidence rather than population-percentile evidence for any individual product category. The four laboratory-prepared samples likewise represent four different cereal raw materials (two buckwheat varieties, oat, rice) with n = 1 per raw material. The total study n = 8 split across eight distinct product-by-preparation combinations means the source contributes one data point per ingredient-by-product cell rather than a distribution.

The source contains two internal Russian-text vs. Table 1 inconsistencies that this page resolves in favor of Table 1: (a) the p. 62 Russian narrative says “the highest Pb is in rice milk «Здоровое меню» at 0.0241 mg/kg = 4.8% of MPC” but Table 1 shows the rice-beverage Pb cell as 0.0296 mg/kg, and the actual study maximum Pb is 0.0530 mg/kg in mature-buckwheat-groat lab milk; (b) the same p. 62 paragraph says Cd “ranged from 0.0106 to 0.0113 mg/kg” but Table 1 shows the Cd range across all four detected samples as 0.0068 to 0.0108 mg/kg. This page uses Table 1 throughout because the table is the primary data record; the narrative values are not propagated.

Audit subagent (2026-06-08, agent a85bea8c) flagged that the Wiki-pages-this-source-may-touch list omitted [[metals/zinc]] and [[metals/copper]] despite the source measuring both metals and despite both metal pages existing in the wiki; verified independently — both pages confirmed present in wiki/metals/ (zinc.md, copper.md). Added both wikilinks. All other audit checks returned ✅ clean; verdict PROMOTE with this single completeness improvement.

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.