Safety of plant extract has to be evaluated in combination with concentration, origin and use. According to the European Food Safety Authority (EFSA) report of 2023, below the daily level of consumption of food-grade plant extract, monkfruit glucoside’s (300 times the sweetness of sucrose) ADI is 4mg/kg body weight and clinical data confirm that its metabolites are non-genotoxic. When the 0.02% concentration is used in Coca-Cola sugar-free drinks, 3 cans (500ml/can) of 60kg adult daily drink only account for 23% of the safety maximum. But unstandardized ephedra extract (ephedrine content >8%) is capable of inducing the risk of arrhythmia, as indicated by the US FDA, and 47 related cases of hospitalization were encountered in the United States from 2019 to 2022, and 82% are “fat-burning supplements” purchased online. In medicine, Novartis’ Phase 3 clinical trial on curcumin extract (pure ≥95%) confirmed that liver dysfunction occurred at only 0.7% at a dosage of 500mg per day for 12 months, which is significantly less than the 3.2% incidence of chemical anti-inflammatory drugs.
Safety measures in the cosmetics industry are more stringent, and L ‘Oreal’s repair essence with 0.5% alpine tinderweed plant extract launched in 2024 showed a sensitization of 0.3% after patch testing, 4.5 times less than phenoxyethanol preservative-containing products. KosMOS of South Korea produced the nano coated green tea polyphenol (particle size 50nm) sunscreen, and its rate of transdermal absorption is 0.08% and conforms to the OECD 428 level of safety in transdermal absorption. However, in a 2023 case of California consumer complaint, it was found that one “natural” facial mask company failed to list the light-sensitive psoralen (extracted from bergamot) and produced solar dermatitis in 12% of its customers, and the total settlement was $2.3 million. In baby and toddler care products, EWG testing revealed that 32% of “plant-derived” wipes contained 1, 4-dioxathracyclic residues (up to 3.7ppm), over twice the California Proposition 65 threshold.
The safety of plant extract in industrial manufacturing must take note of degradation products. Dupont’s castor oil (30% extract) bioplastics were shown to be biocompatible according to the ISO 10993 test, but dioxins produced on incineration still contributed 0.8ng TEQ/g, 94% lower than regular plastics. A 2023 research by the Chinese Academy of Agricultural Sciences found that matrine biopesticide at a concentration of 0.3% had a half-life of just 5.2 days after being applied to soil, and LC50 (50% lethal concentration) against earthworms was 480mg/kg, 1/120 that of chemical pesticide chlorpyrifos, but the bee mortality when they came in contact with residues within 7 days after application was still 8.7%. In food processing, supercritical CO2 extraction technology reduces the residue of solvent from 500 PPM in ethanol extraction to <5ppm, and the Buchi smart system of Switzerland can adjust the proportion of ginkgo acid in the extract of Ginkgo biloba to <1ppm, following EP10 pharmacopeia standards.
Regulatory variations significantly influence safety performance. Japan’s “Pharmaceutical Law” requires plant extract health foods to specify the fluctuation range of active ingredients (e.g., soybean isoflavones labeled with 40%±5%), while the US DSHEA Act allows ±20% fluctuation. As a result, the 2022 ConsumerLab test found that 32% of the actual content of American products was below the nominal value. In medicine, WHO included artemisinin extract (purity ≥98%) in the list of essential medicines in 2021, but noted that it must be formulated together with ACT therapy (artemisinin combination drug), and when used independently, resistance to malaria parasites increased by 1.7% to 12% within a three-year span. The stability was significantly improved by the application of microencapsulation technology (embedding rate ≥95%), and the shelf life of vitamin C and acerola cherry plant extract composite preparation was increased from 6 months to 24 months and the rate of oxidative degradation dropped from 23% to 4.5%. As tighter international regulation, the price of plant extract’s GMP certification will increase by 18% in 2025 but the incidence rates of adverse event reporting on products can be reduced by 41%.