Overview
Researchers at the Technical Research Centre of Finland (VTT Ltd) and the Finnish Food Authority conducted a narrative review of chemical food-safety hazards and nutritional properties in plant-based dairy alternatives (PBDAs) and plant-based meat alternatives (PBMAs). The review focuses on European regulatory context and synthesizes published studies on heavy metals, pesticide residues, mycotoxins, and other chemical hazards in soy, oat, almond, rice, and other plant-based beverages. For heavy metals, the paper compiles concentration ranges from multiple primary studies and flags regulatory gaps, particularly the absence of harmonized EU maximum levels for most heavy metals in PBDAs outside of inorganic arsenic in rice drinks and limits for infant formula. The Finnish Food Authority risk assessment findings on nickel in soy drinks are highlighted as a concern for nickel-sensitized individuals.
Key numbers
All values below come from the review’s Table 2, which compiles ranges of mean values across multiple cited primary studies. Where multiple references are cited, the range spans the lowest and highest reported means. Units are as stated in the source; µg/L and µg/kg are both present depending on the original study’s basis. The review does not present original measurements; values are sourced from studies cited in the review’s reference list.
Heavy metal concentration ranges in plant-based drinks (Table 2, compiled from multiple studies)
| Metal | Soy | Oat | Almond | Rice | Coconut / other |
|---|---|---|---|---|---|
| aluminum (Al) (µg/L or µg/kg) | 176 to 3,930 µg/L | 65 to 304 µg/kg | 695 µg/kg | 50 to 375 µg/kg | not tabulated |
| total arsenic (tAs) (µg/kg) | 1.1 to 16 µg/kg | 0.9 µg/kg | 0.8 µg/kg | 12.8 to 16.3 µg/kg | 0.7 to 3 µg/kg (coconut, hemp, millet) |
| inorganic arsenic (iAs) (µg/L or µg/kg) | not separately tabulated | not separately tabulated | not separately tabulated | 2.3 µg/L to 15.6 µg/kg | not separately tabulated |
| cadmium (Cd) (µg/L or µg/kg) | 2 to 3.9 µg/L | 0.4 to 0.5 µg/kg | 0.09 µg/kg | 0.6 to 1.2 µg/kg | not tabulated |
| nickel (Ni) (µg/L or µg/kg) | less than 25.7 to 201 µg/kg (mean 255 µg/kg in one dataset) | 127 to 130 µg/kg | 36.6 µg/kg | 30 to 57.5 µg/kg | not tabulated |
| lead (Pb) (µg/L or µg/kg) | 0.3 to 10 µg/L | 0.2 µg/kg | 0.9 µg/kg | 0 to 7 µg/L | not tabulated |
| tin (Sn) (µg/kg) | 3,400 to 14,800 | not tabulated | 6,600 to 20,700 | not tabulated | 12,000 to 30,400 (coconut) |
| chromium (Cr) (µg/kg) | 12.9 | 8.3 | 38 | 16.1 | not tabulated |
The wide range for soy aluminium (176 to 3,930 µg/L) reflects high inter-study and inter-product variability; the review attributes this to differences in soy processing and water quality. Tin values reported for nut- and coconut-based drinks are from packaging migration work (Karasakal 2020 cited in the review), not from beverage-only surveys.
Key narrative findings
On arsenic: the review states that “drinks can be a large source of inorganic arsenic, and only rice-based beverages have currently maximum levels set for inorganic arsenic content in EU legislation.” The applicable EU instrument is Regulation EU 2023/915, which sets an inorganic arsenic (iAs) maximum level of 30 µg/kg in non-alcoholic rice-based drinks. The review notes that Austrian authority AGES measured highest total arsenic in full-corn rice drinks at a maximum of 59.8 µg/kg, and flags that nut-based drinks may also be a source of elevated inorganic arsenic although data are scarce.
On cadmium: soy-based products carry the highest cadmium concentrations among PBDA types. Dairy and milk products contribute 1 to 12 percent of total cadmium exposure in European children; soy-based alternatives show higher cadmium (Cd) than cow’s milk.
On nickel: soy drinks show concentrations that “can be higher than in animal-based alternatives.” A Finnish Food Authority risk assessment (Suomi et al. 2020, cited in the review) reported mean nickel (Ni) in soy drinks of 275 µg/kg and concluded that this “may indicate adverse effect already at 4.42 µg daily” for nickel-sensitized persons. The applicable EU nickel maximum levels are 250 µg/kg for cow-milk infant formula and 400 µg/kg for soy-based infant formula.
On lead: the review notes that 90 to 100 percent of monitoring samples were below the LOQ across most PBDA types, with occasional elevated values in soy drinks (maximum 40.1 µg/kg, lower-bound scenario) and rice drinks (maximum 50 µg/kg). These are exception findings, not central tendencies.
Regulatory limits cited in the review
| Product class | Metal | EU maximum level | Instrument |
|---|---|---|---|
| Non-alcoholic rice-based drinks | iAs | 30 µg/kg | EU 2023/915 |
| Liquid infant formula | Cd | 10 µg/kg | EU infant formula regulation |
| Liquid infant formula | Pb | 10 µg/kg | EU infant formula regulation |
| Dry infant formula | Cd | 20 µg/kg | EU infant formula regulation |
| Dry infant formula | Pb | 20 µg/kg | EU infant formula regulation |
| Cow-milk infant formula | Ni | 250 µg/kg | EU infant formula regulation |
| Soy-based infant formula | Ni | 400 µg/kg | EU infant formula regulation |
Methods (brief)
This is a narrative review; no original measurements are reported. The authors searched published literature, EU regulatory documents, and Finnish Food Authority monitoring databases. Primary studies cited cover a range of markets, years, and analytical methods; the review does not describe a systematic search protocol or assess primary-study risk of bias. Table 2 is a compiled summary of heavy-metal concentration ranges from multiple cited primary studies; individual study details (sample sizes, analytical methods, matrix specifications) are found in the original studies cited.
Evidence fitness
The review provides useful regulatory context, a synthesized overview of the range of heavy-metal concentrations across PBDA types, and Finnish-market risk assessment findings on nickel. It does not substitute for primary occurrence studies for any single PBDA type. Its Table 2 values are ranges across multiple studies and must not be treated as single-study measurements. Where specific numeric values are needed for contamination profiling, the primary studies cited in the review (Astolfi 2020, Schryvers 2025, Ruzik and Jakubowska 2022, Suomi 2020) should be consulted directly.
Limitations
Narrative review without systematic search protocol or quality appraisal of primary studies. Table 2 ranges mix µg/L and µg/kg bases across studies; some values are from liquid-basis measurements, some from wet-weight per-kg measurements. Units differ between rows and must not be compared without basis alignment. The soy tin values derive from a packaging-migration study and do not represent beverage-intrinsic tin content. The review’s risk commentary on nickel in soy drinks pertains specifically to nickel-sensitized individuals, not to the general population.
Related evidence
- Plant-based beverages
- Plant Milks, Soy-Based
- Plant Milks (Almond, Oat, Coconut, Other Non-Soy/Non-Rice)
- Rice beverages (rice milk)
- Plant milk base
- Soy
- Rice
- Oat
- Almond
- Arsenic, Inorganic
- Arsenic, Total
- Cadmium
- Nickel
- Lead
- Aluminum
- EU inorganic arsenic maximum level for non-alcoholic rice-based drinks
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