Though a variety of names were in use for many years, “Eisenblau” (Iron Blue) became the official designation under the German DIN 55 906 norm, with the general properties of complex iron cyanides used as coloring agents falling under the heading “Iron Blue Pigments” as per the international DIN ISO 2495 standard. Iron blue is listed as CI 77 510 Pigment Blue 27 in the Color Index (CI).

So-called soluble blue is listed under CI 77 520 Pigment Blue 27. The CAS number is as follows:
VOSSEN-BLAU®: 25869-00-5

Experience with humans

Findings collected over the past decades in the context of manufacturing and processing of iron blue pigments have shown no significant detrimental effects on humans when used as directed.

Acute toxicity

Acute toxicity, oral trials with rats LD50, lies above 5.110 mg/kg. Amounts exceeding 5.000 mg/kg are considered non-toxic. Application of iron blue pigments on the eye of a rabbit did not have a sensitizing effect.


Iron blue pigments are listed as a “non-hazardous to water” substance (ID# 1843) in the official “substances hazardous to water” catalog. The Commission on Substances Hazardous to Water (Kommission zur Bewertung wassergefährdender Stoffe – KBwS) lists the aforementioned product in the Dangerous to Water Class 1 (WGK) 1.

Legal Classification

Based on currently applicable standards of Chemical Substance Legislation, the Hazardous Substance Advisory and Transportation Regulations, Degussa precipitated iron blue pigments are not classified as dangerous substances or goods.

You can obtain further information on product safety or our product safety sheets from the relevant contact.