Pigment Red 3 - information sheet

2-Naphthalenol, 1-[(4-methyl-2-nitrophenyl)azo]-
CAS Registry Number 2425-85-6

Updated July 27, 2020:

The Final Screening Assessment for Pigment Red 3 was published on March 7, 2009, under the Challenge initiative of the Chemicals Management Plan (CMP). The assessment is summarized in this information sheet (formerly public summary) and has not changed. The section in this information sheet entitled "Preventive actions and reducing risk" communicates updates in risk management activities, namely:

On this page


  • The Government of Canada conducted a science-based evaluation, called a screening assessment, to address the potential for harm to Canadians and to the environment from Pigment Red 3.
  • Under the Canadian Environmental Protection Act, 1999 (CEPA 1999), the risk posed by a substance is determined by considering both its hazardous properties (its potential to cause adverse human health or ecological effects) and the amount of exposure there is to people and the environment. A substance may have hazardous properties; however, the risk to human health or to the environment may be low depending upon the level of exposure.
  • As a result of the screening assessment, the Government concluded that Pigment Red 3 is harmful to human health, but not to the environment.

About this substance

  • The screening assessment focused on the substance 2-naphthalenol, 1-[(4-methyl-2-nitrophenyl)azo]-, also referred to as Pigment Red 3. This substance was assessed as part of Batch 3 of the Challenge initiative of the CMP.
  • Additionally, Pigment Red 3 was also included in 2016 in the subgroup Certain Monoazo Pigments in the Aromatic Azo and Benzidine-based Substance Grouping. The conclusion previously made under the Challenge initiative that Pigment Red 3 is harmful to human health but not the environment remained unchanged.
  • Pigment Red 3 does not occur naturally in the environment. According to information gathered at the time of its assessment, Pigment Red 3 was reported to be used primarily in paints, but also in 3 cosmetic products: a nail polish and 2 soaps.

Human and ecological exposures

  • The assessment indicated that Canadians may be exposed to Pigment Red 3 through the use of certain products available to consumers, such as paints and cosmetics.
  • This substance may be released to the environment during product manufacturing and industrial processes. Releases are also expected to occur from flaking and chipping of paints during industrial and consumer use.

Key health and ecological effects (hazard)

  • The important or critical effect used for characterizing the risk to human health from Pigment Red 3 was carcinogenicity (potential to cause cancer).
  • For the ecological assessment, Pigment Red 3 was considered to have negligible to low potential for toxicity to aquatic organisms.

Risk assessment outcomes

Screening assessment conclusions

  • The Government concluded that Pigment Red 3 is harmful to human health.
  • The Government also concluded that Pigment Red 3 is not entering the environment at levels that are harmful to the environment.
  • It was also concluded that Pigment Red 3 meets the criteria for persistence but not the criteria for bioaccumulation as set out in the Persistence and Bioaccumulation Regulations of CEPA 1999.

Preventive actions and reducing risk

Performance measurement

  • The Government conducts performance measurement on the risk management of substances that are concluded to be toxic (harmful to human health and/or the environment) under CEPA 1999. This is done to determine whether actions taken to protect human health or the environment are effective over time.
  • On July 27, 2020, the Government published a Performance Measurement Evaluation for Risk Management of Pigment Red 3. The evaluation concluded that the risk management actions taken have been successful in helping to protect the health of Canadians from concerns identified in the screening assessment.
  • The SNAc provisions and monitoring of cosmetic ingredient notifications to Health Canada are sufficient for tracking potential new exposures of concern. Also, if new information becomes available on Pigment Red 3, such as exposure or hazard information, it will be considered through the Identification of risk assessment priorities  process.

Related information

Page details

Date modified: