US EPA

In March 2023, EPA released the Protocol for the Naphthalene IRIS Assessment (Preliminary Assessment Materials) for a 30-day public review and comment period. As part of developing a draft IRIS assessment, EPA presents a protocol that describes the methodology for how the assessment will be conducted, including systematic review and dose-response. These could include strategies for literature searches, criteria for study inclusion or exclusion, considerations for evaluating study methods, information management for extracting data, approaches for synthesis within and across lines of evidence, and methods for derivation of toxicity values.

U.S. EPA. Protocol for the Naphthalene IRIS Assessment (Preliminary Assessment Materials). U.S. Environmental Protection Agency, Washington, DC, EPA/635/R-23/030, 2023.

Naphthalene is a white crystalline solid with an aromatic odor. Naphthalene is naturally occurring and is most abundantly found in coal, tar, and petroleum. Naphthalene is mainly used in the manufacture of dyes, surfactants, leather tanning reagents, dispersants, pesticides, resins, solvents, and chemical intermediates. Major consumer products containing naphthalene include moth repellents, in the form of mothballs or crystals, and toilet deodorant blocks. Naphthalene is used as a fragrance in non-food use pesticide products, while naphthalene derivatives are also used as inert ingredients in non-food use pesticide products regulated by EPA. Lastly, naphthalene is a constituent of tobacco smoke.

Date	Description
01-Aug 1998	EPA revised the IRIS Summary and Toxicological Review of Naphthalene and released an external review draft for public comment.
02-Jul 2004	EPA released a revised IRIS Summary and Toxicological Review of Naphthalene (External Review Draft) for public comment and hosted an peer review panel meeting.
03-Apr 2005	EPA hosted a Peer Consultation Workshop on research needs related to the mode of action of inhalation carcinogenicity on April 7, 2005.
04-Aug 2005	EPA released the document Research Needs Related to Naphthalene Assessment summary report from the workshop.
05-Jul 2014	EPA released the IRIS Toxicological Review of Naphthalene (Scoping and Problem Formulation Materials) for discussion at a public science meeting held on September 3-4, 2014 to provide the opportunity for the public to give input on the developing draft assessment.
06-Jul 2018	EPA released the IRIS Assessment Plan of Naphthalene (Scoping and Problem Formulation) for a 30-day public comment period. An August 23, 2018 IRIS Public Science Webinar to discuss the document was also announced. [Federal Register Notice Jul 5, 2018]
07-Aug 2018	EPA has announced that the August 23, 2018 IRIS Public Science Meeting was postponed until the IRIS Program identified suitable public science meeting dates in the near future. Stakeholders wishing to provide written comments to the IRIS Program were invited to continue to do so through the docket on Regulations.gov until September 5, 2018.
08-Apr 2019	EPA suspended the assessment in fiscal year 2019. It may be restarted as Agency priorities change.
09-Mar 2021	The IRIS assessment of naphthalene was released from suspension and announced in the June 2021 IRIS Program Outlook.
10-Sep 2021	EPA updated the IAP and posted an errata sheet outlining the changes that were made to the draft assessment and posted on this site on Sep 30, 2021.
11-Sep 2021	EPA announced the rescheduling of the IRIS Public Science Meeting for Naphthalene to be held on November 9, 2021 to discuss the key science issues identified in the 2018 IRIS Assessment Plan (IAP).
12-Nov 2021	EPA held the IRIS Public Science Meeting for Naphthalene on November 9, 2021 to discuss the key science issues identified in the 2018 IRIS Assessment Plan (IAP).
13-Mar 2023	EPA released the Protocol for the Naphthalene IRIS Assessment (Preliminary Assessment Materials). [Federal Register Notice March 17, 2023]

The IRIS Program will use the protocol to develop the draft assessment.

This download(s) is distributed solely for the purpose of pre-dissemination peer review under applicable information quality guidelines. It has not been formally disseminated by EPA. It does not represent and should not be construed to represent any Agency determination or policy.

• Protocol for the Naphthalene IRIS Assessment (Preliminary Assessment Materials) (PDF)  (186 pp, 3 MB, about PDF)

If you have a disability and the format of any material on our web pages interferes with your ability to access the information, please reach out to us using the Contact us about IRIS form for assistance. To enable us to respond in a manner most helpful to you, please indicate the nature of the accessibility problem, the web address of the requested material, your preferred format in which you want to receive the material (electronic format (ASCII, etc.), standard print, large print, etc.), and your contact information.

• IRIS Toxicological Review of Naphthalene (2014, Scoping and Problem Formulation Materials)
• IRIS Assessment Plan for Naphthalene (2018, Scoping and Problem Formulation Materials)
• IRIS Program Outlook April 2019-Suspended/Discontinued Assessment

• Primary Literature Search References Sorted By Author (Naphthalene)

• FR Notice: March 17, 2023

Comments on the assessment may be submitted and reviewed using the Docket ID EPA-HQ-ORD-2014-0527