Bamboo and other powdered plant-based materials are sometimes added to melamine-formaldehyde resin to label products as ‘natural’ or ‘eco-friendly’. Unfortunately, plant-based materials in plastics are known to accelerate the degradation of certain polymers they are mixed with causing starting substances and additives within the plastic polymers to migrate at higher rates into the foods (FPF reported).
Shaojie Liu of Fujian Medical School in China and collaborators published a study of melamine-based tableware from China in the journal Toxics in February 2024. Liu et al. purchased 11 different brands of melamine-, bamboo-, wheat straw- made tableware (24 bowls and 22 cups) with each sample duplicated 3-5 times as well as 3 brands of glass- and ceramic-made tableware (2 bowls and 2 cups) from internet or retail shops in Shanghai, China. The researchers measured migration of melamine (CAS 108-78-1) and three derivatives: cyanuric acid (CAS 108-80-5), ammeline (CAS 645-92-1), and ammelide (CAS 645-93-2) from all the samples following the test conditions of the European Union Reference Laboratory for Food Contact Materials.
Melamine migration exceeded China’s specific migration limit of 0.2 mg/dm2 in 35% of the bamboo-melamine tableware samples, 2.3% of the pure melamine samples, and 0% the wheat straw samples.
Many melamine products are targeted at children and parents. When the migration results were combined with potential exposure levels for 1 year old infants at the strictest regulatory tolerable daily intake levels, Liu et al. found that potentially 100% of the bamboo-melamine products lead to over-exposure to melamine.
The study’s conclusions emphasize a need for caution among consumers and manufacturers. The high migration levels found in some bamboo and melamine products could pose health risks, particularly with prolonged use. The authors recommend avoiding the use of these materials, especially for hot foods that could increase the rate of chemical leaching, “so as to decrease the risk of developing melamine-related diseases.”
Melamine is suspected to be carcinogenic (FPF reported) and “under assessment” at the EU for being both persistent, bioaccumulative and toxic (PBT) as well as endocrine disrupting. These properties supported its addition to the EU Candidate List of substances of very high concern in January 2023 (FPF reported). The EU ran an enforcement Action plan in 2022 against plastic food contact materials containing bamboo powder (FPF reported).
Reference
Liu, Shaojie, et al. (2024). “Migration of melamine and its derivatives from melamine/bamboo/wheat straw-made tableware purchased from internet markets or retail shops in China.” Toxics. DOI: 10.3390/toxics12020143
