IRIS Toxicological Review of Butyl Benzyl Phthalate (BBP) (Preliminary Assessment Materials, 2014)

Abstract

In September 2014, EPA released the draft literature searches and associated search strategies, evidence tables, and exposure response arrays for BBP to obtain input from stakeholders and the public prior to developing the draft IRIS assessment. Specifically, EPA was interested in comments on the following:

• Draft literature search strategies
• The approach for identifying studies
• The screening process for selecting pertinent studies
• The resulting list of pertinent studies
• Preliminary evidence tables
• The process for selecting studies to include in evidence tables
• The quality of the studies in the evidence tables

The literature search strategy, which describes the processes for identifying scientific literature, contains the studies that EPA considered and selected to include in the evidence tables. The preliminary evidence tables and exposure-response arrays present the key study data in a standardized format. The evidence tables summarize the available critical scientific literature. The exposure-response figures provide a graphical representation of the responses at different levels of exposure for each study in the evidence table.
Butyl benzyl phthalate (BBP), also referred to as 1,2 benzenedicarboxylic acid, butyl phenylmethyl ester, and benzyl n-butylphthalate, is a clear, oily liquid at room temperature. BBP is formed from the reaction of the monobutyl ester of phthalic acid with benzyl chloride and butanol.

The main uses of BBP are as a plasticizer for vinyl flooring, vinyl foams, and carpet backing. Other products which are plasticized with BBP are cellulose plastics, polyvinyl acetate, polysulfides, and polyurethane. More specifically, BBP is used as a plasticizer in polyvinyl chloride used to make food conveyer belts, carpet tiles, artifical leather, tarps, automotive trim, weather stripping, traffic cones, and to a limited amount in production of vinyl gloves. BBP is also used in some adhesives.

BBP is released to the environment during its production and when used as a plasticizing agent. In addition, use and disposal of products plasticized with BBP may lead to exposures.

The reassessment will present reference values for the noncancer effects of BBP (RfD and RfC), where supported by available data, and a cancer assessment. The assessment will be subject to internal and external peer review along with Agency review. The final product will reflect the Agency opinion on the toxicity of BBP.

Impact/Purpose

The U.S. EPA is conducting a reassessment of the scientific basis supporting the human health risk assessment of butyl benzyl phthalate (BBP) that will appear on the Agency's online database, the Integrated Risk Information System (IRIS). IRIS is an EPA database containing Agency consensus scientific positions on potential adverse human health effects that may result from chronic (or lifetime) exposure to chemicals in the environment. IRIS contains chemical-specific summaries of qualitative and quantitative health information in support of two steps of the risk assessment process, i.e., hazard identification and dose-response evaluation. IRIS assessments are used in combination with specific situational exposure assessment information to evaluate potential public health risks associated with environmental contaminants.

Citation

U.S. EPA. IRIS Toxicological Review of Butyl Benzyl Phthalate (BBP) (Preliminary Assessment Materials, 2014). U.S. Environmental Protection Agency, Washington, DC, EPA/635/R-11/008, 2014.

Date	Description
01- Dec 2008	The National Academies of Sciences (NAS) released the final report, Phthalates and Cumulative Risk Assessment: The Task Ahead.
02- Sep 2014	EPA released the draft literature searches and associated search strategies, evidence tables, and exposure response arrays for BBP to obtain input from stakeholders and the public prior to developing the draft IRIS assessment.
03- Feb 2015	EPA hosted an IRIS public science meeting on February 25-26, 2015, to provide an opportunity for the public to give input and participate in an open discussion regarding preliminary materials that were prepared for the IRIS chemical, butyl benzyl phthalate (BBP), prior to the development of 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.

• Scoping Information, Preliminary Literature Search, Associated Strategy and Evidence Tables for BBP (PDF)  (282  pp, 4.6 MB, about PDF)
• BBP Errata Sheet (PDF)  (1  pp, 358.4 KB, about PDF)
• HERO Primary literature search references sorted by author (BBP) (dynamic literature link - generated by HERO, leaving the IRIS website)
• HERO Literature selection process for the BBP primary literature (dynamic literature link - generated by HERO, leaving the IRIS website)
• HERO Mechanistic table (BBP) (dynamic literature link - generated by HERO, leaving the IRIS website)
• HERO Targeted literature search for epidemiological references sorted by author (phthalate) (dynamic literature link - generated by HERO, leaving the IRIS website)
• HERO Literature selection process for the BBP targeted epidemiological literature (dynamic literature link - generated by HERO, leaving the IRIS website)
• IRIS Public Science Meeting (Feb 2015)

Related Link(s)

• Phthalates and Cumulative Risk Assessment (NAS Final Report)