Taiwan Updates Risk Assessment Guidelines for Cosmetics Containing Nanomaterials

In July 2015, Taiwan Food and Drug Administration (TFDA) introduced the Guidelines for Risk Assessment of Cosmetics with Nanomaterials (the Guidelines), aiming to strengthen cosmetics management and assist stakeholders in evaluating the safety of cosmetics containing nanomaterials. To ensure the continued applicability of the Guidelines, TFDA released an updated version on November 8, 2024.¹

Compared to its predecessor, the updated Guidelines primarily revises the assessment items for cosmetics containing nanomaterials. The risk assessment for such cosmetics focuses on two main areas: physical and chemical property analysis, as well as safety evaluation. While the previous version included assessment items for both nanomaterials and the finished product, the updated Guidelines specifies items only for nanomaterials, and add four additional assessment items. The table below serves as a current reference for stakeholders conducting nanomaterial assessments.

Items		Requirement ⁽¹⁾
Physical and chemical properties	Chemical identity	O
	Solubility/Dispersibility	O
	Size/Size distribution	O
	Shape	O
	Aggregation/Agglomeration in relevant media	O
	Surface chemistry	O
	Surface charge	O
	Surface area	O
	Chemical composition	O
	Purity	O
	Density and Pour density	O
	Crystal structures	O
	Stability	O
	UV absorption	△
	Partition coefficient	O
	Catalytic activity	△
Safety assessment dossiers ⁽²⁾	Acute toxicity ⁽³⁾	O
	Irritation and corrosivity	O
	Skin sensitization	O
	Dermal/Percutaneous absorption	O
	Repeated dose toxicity	O
	Mutagenicity/Genotoxicity ⁽⁴⁾	O
	Carcinogenicity	△
	Reproductive toxicity	△
	Toxicokinetic	O
	Photo-induced toxicity	O
	Margin of Safety (MoS)	O
	Likelihood and extent of internal exposure via skin, lung or oral route considering the use type	O
*Notes:* (1) O: mandatory dossiers, △: case-by-case dossiers; (2) Under Article 6(4) of the Cosmetic Hygiene and Safety Act, animal testing for cosmetics and cosmetic ingredients is prohibited in Taiwan when conducting safety evaluation, except with permission from TFDA. (3) The safety can be evaluated using evidence from methods such as in vitro testing, computer (in silico) models, weight of evidence (WoE) approaches, etc. (4) Due to the properties of nanomaterials, bacteria are unlikely to be penetrated by them. Therefore, it is recommended to use methods such as the In Vitro Mammalian Cell Micronucleus Test (OECD TG 487) and the In Vitro Mammalian Cell Gene Mutation Tests (OECD TG 476), while the Bacterial Reverse Mutation Test (OECD TG 471) is not suitable.

In addition to the primary revisions mentioned above, the newly released Guidelines modifies the definition of cosmetics, and updaters the reference documents mentioned in the Guidelines, to ensure alignment with the latest versions. Further details on these amendments can be found in the updated Guidelines.