Intent to Change the Basis for Listing as Known to the State of California to Cause Reproductive Toxicity: Hexafluoroacetone and Phenylphosphine

The California Environmental Protection Agency’s Office of Environmental Health Hazard Assessment (OEHHA) intends to change the basis for the listing of hexafluoroacetone and phenylphosphine as known to the state to cause reproductive toxicity under the Safe Drinking Water and Toxic Enforcement Act of 1986.¹ These chemicals (hexafluoroacetone on August 1, 2008 and phenylphosphine on August 7, 2009) were added to the Proposition 65 list as known to cause reproductive toxicity pursuant to Labor Code Section 6382(d) which is incorporated by reference in Health and Safety Code Section 25249.8(a).
OEHHA intends to modify the basis of these listings as shown in the table below. Both chemicals will continue to be listed via the Labor Code mechanism.²

*CCR is the Cal. Code of Regs. ACGIH is the American Conference of Governmental Industrial Hygienists.

** ACGIH 1977. Documentation of the threshold limit values for substances in workroom air with supplements for those substances added or changed since 1971, 3rd ed., 4th printing. Supplements for those Substances Added or Changed, Years 1971-1973.

*** Developmental toxicity was incorrectly noted in the original listing.
OEHHA is initiating this action based on changes to the federal regulations that affect the basis for the original listing. Specifically, in March 2012, the federal Occupational Safety and Health Administration (OSHA) amended the regulations contained in CFR Title 29, section 1910.1200. These changes have affected the use of this section of Title 29 as a definitive source for identifying chemicals that are known to cause reproductive toxicity.

Background on listing via the Labor Code mechanism: Health and Safety Code section 25249.8(a) incorporates Labor Code Sections 6382(b)(1) and 6382(d) into Proposition 65. OEHHA must list substances identified by reference in Labor Code Section 6382(b)(1) or by reference in Labor Code Section 6382(d) as causing cancer or reproductive toxicity.

Labor Code section 6382(d) states, “[I]n addition to those substances on the director's list of hazardous substances, any substance within the scope of the federal Hazard Communication Standard (29 C.F.R. Sec. 1910.1200) is a hazardous substance subject to this chapter.”[emphasis added]

By referencing “the director’s list,” Section 6382(d) expressly refers to chemicals that appear on the List of Hazardous Substances prepared by the Director of the Department of Industrial Relations pursuant to Labor Code section 6380. Chemicals are added to the Director’s List through several routes, including chemicals identified via Title 8, Cal. Code of Regs., section 5155, Airborne Contaminants (Table AC-1. Permissible Exposure Limits for Chemical Contaminants). The basis for the addition of hexafluoroacetone and phenylphosphine to the Director’s List was the chemicals’ inclusion in Table AC-1 based on the American Conference of Governmental Industrial Hygienists’ (ACGIH) Supplements for those Substances Added or Changed, Years 1971-1973.³Copies of the documentation are available from OEHHA via the contact information provided below.

OEHHA is the lead agency for Proposition65 implementation. OEHHA evaluates whether listing under Proposition 65 is required under the Labor Code mechanism by determining the toxicological basis relied on by the Department of Industrial Relations in adding a chemical to the Director’s list.

OEHHA’s determination: The basis for addition of hexafluoroacetone and phenylphosphine to the Director’s List is a risk of male reproductive toxicity.
In making this determination, OEHHA relied upon the following documents, which are included in the administrative record for this action:

1. The Director’s List

In developing the California Department of Industrial Relations (DIR) Hazardous Substances List (The Director’s List) (Cal. Code of Regs., Title 8, section 339, adopted in 1983), the Director draws from several sources pursuant to Labor Code section 6382 including: (1) International Agency for Research on Cancer (IARC); (2) U.S. Environmental Protection Agency lists pursuant to the federal Clean Air and Clean Water Acts; (3) Substances listed by the state Occupational Safety and Health Standards Board as airborne chemical contaminants; (4) California Department of Pesticide Regulation's list of Restricted Materials; (5) Information Alerts put out by the state’s Hazard Evaluation and Information Service pursuant to Labor Code Section 147.2.

As relevant to the current listings, both hexafluoroacetone and phenylphosphine were added to the Director’s List because they were listed as airborne chemical contaminants by the state Occupational Safety and Health Standards Board based on their inclusion in California’s General Safety Order Section 5155.

1. General Industry Safety Order Section 5155 Rulemaking Documents

Hexafluoroacetone and phenylphosphine appear in Table AC-1 of California’s General Industry Safety Order Section 5155. The state Occupational Safety and Health Standards Board adopted the Section 5155 order and its accompanying tables in 1975 to “regulate employee exposure to airborne substances in order to assure… that no employee will suffer material impairment of health or functional capacity” if exposed to these chemicals.⁴

A May 30, 1975 memo from Frederick Hodges, M.D. with the Health Protection Division of Cal/OSHA to Ronald T. Renaldi, then the Director of Cal/OSHA Standards Board, explains that Table AC-1, which lists permissible exposure limits for the airborne contaminants, was based on threshold limit values (TLVs) adopted by ACGIH. The memo states that the chemicals and TLVs for Table AC-1 are based in relevant part on “subsequent changes and additions instituted by the ACGIH during the period 1970-1974.”

The ACGIH 1977 publication, Documentation of the threshold limit values for substances in workroom air with supplements for those substances added or changed since 1971, contains supplements that describe these “subsequent changes and additions.”⁵ These supplements are the source of the information used by the state Occupational Safety and Health Standards Board in adopting the Section 5155 order. Because the Board relied only upon information available to it at the time of the rulemaking, OEHHA exclusively is using the 1971-1973 supplements in this current listing.

1. ACGIH’s Documentation of the Threshold Limit Values for Substances in Workroom Air (1971-1973 Supplements)

The 1971-1973 ACGIH Threshold Limit Values documentation⁶ discusses the health effects of the chemicals evaluated by ACGIH. These chemicals include hexafluoroacetone and phenylphosphine.

Hexafluoroacetone

The ACGIH documentation for hexafluoroacetone⁷ specifies that the TLV was based on a 1971 Haskell Laboratory Report noting severe but reversible testicular damage in rats and dogs exposed to hexafluoroacetone. It further discusses a separate study in rats that demonstrated decreased spermatogenesis in the animals after repeated exposures to higher doses. The level of exposure in the Haskell Laboratory study that caused severe testicular damage was considered injurious to both rats and dogs, and the TLV was based on a lower exposure level in that study that was identified as a “no-effect level.”

Phenylphosphine

The ACGIH documentation for phenylphosphine⁸ cites a 1970 Haskell Laboratory Report that noted testicular effects, including irreversible testicular damage in rats and beagle dogs exposed to phenylphosphine at chronic levels. On the basis of this report, ACGIH recommended a threshold level that was below the level that caused these effects. The threshold level adopted by ACGIH and relied upon for the Cal/OSHA rulemaking was in part based upon male reproductive effects, specifically testicular damage.

Request for comments: OEHHA is requesting comments as to whether these chemicals meet the criteria set forth in the Proposition65 regulations for listings via the Labor Code mechanism. Because these are ministerial listings, comments should be limited to the appearance of these chemicals on the Director’s List or on the Section 5155 list. OEHHA cannot consider scientific arguments concerning the weight or quality of the evidence considered by Cal/OSHA, and will not respond to such comments if they are submitted.

In order to be considered, OEHHA must receive comments by 5:00 p.m. on MONDAY, OCTOBER 21, 2013. We encourage you to submit comments in electronic form, rather than in paper form. Comments transmitted by e-mail should be addressed to P65Public.comments@oehha.ca.gov. Please include “Labor Code - HEXAFLUOROACETONE” or “Labor Code - PHENYLPHOSPHINE” in the subject line. Comments submitted in paper form may be mailed, faxed, or delivered in person to the address below.

Mailing Address:

Office of Environmental Health Hazard Assessment
P.O. Box 4010, MS-19B
Sacramento, California 95812-4010
Fax:(916) 323-2265
Street Address:1001 I Street
Sacramento, California 95814

Any public comments received will be posted after the close of the comment period. If you have any questions, please contact OEHHA at P65.Questions@oehha.ca.gov  or at (916) 445-6900.

Comment Period

• Comment Period - Intent to Change the Basis for Listing as Known to the State of California to Cause Reproductive Toxicity: Hexafluoroacetone and Phenylphosphine

Related Notices

• Request for Comments on Proposed Listing of Gallium Arsenide as Known to Cause Cancer and Hexafluoroacetone, Nitrous Oxide and Vinyl Cyclohexene Dioxide as Known to Cause Reproductive Toxicity

  Jun 15, 2007
• Chemicals Listed Effective August 1, 2008 as Known to the State of California to Cause Cancer or Reproductive Toxicity: gallium arsenide, hexafluoroacetone, nitrous oxide and vinyl cyclohexene dioxide

  Aug 1, 2008
• Notice to Interested Parties Proposition 65 Listed Chemicals Affected by Hazard Communications Standard Amendments

  Sep 20, 2013

Footnotes and References

¹ Commonly known as Proposition65, the Safe Drinking Water and Toxic Enforcement Act of 1986 is codified in Health and Safety Code section 25249.5 et seq.

² See Health and Safety Code section25249.8(a) and Labor Code Section 6382(d).

³ American Conference of Governmental Industrial Hygienists. 1977. Documentation of the threshold limit values for substances in workroom air with supplements for those substances added or changed since 1971, 3rd ed., 4th Supplements for those Substances Added or Changed, Years 1971-1973.

⁴ Occupational Safety and Health Standards Board, 1982. Initial Statement of Reasons, General Industry Safety Order 5155, Airborne Contaminants

^5,6,7,8 American Conference of Governmental Industrial Hygienists. 1977. Documentation of the threshold limit values for substances in workroom air with supplements for those substances added or changed since 1971, 3rd ed., 4th Supplements for those Substances Added or Changed, Years 1971-1973