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Exposure Assessment: Potential for the Presence of Phthalates in Specified Materials at Concentrations Above 0.1 Percent”

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Exposure Assessment: Potential for the Presence of Phthalates in Specified Materials at Concentrations Above 0.1 Percent” CPSC Staff Statement on the Toxicology Excellence for Risk Assessment Report, “Exposure Assessment: Potential for the Presence of Phthalates in Specified Materials at Concentrations Above 0.1 Percent” August 2016 The report, Exposure Assessment: Potential for the Presence of Phthalates in Specified Materials at Concentrations Above 0.1 Percent, presents the findings of research conducted by the Toxicology Excellence for Risk Assessment Center at the University of Cincinnati (TERA Center), under a contract with the U.S. Consumer Product Safety Commission (CPSC). The TERA Center performed this research to summarize available information on the production and use of specified plastics, regarding the possibility that these plastics contain certain phthalates at concentrations greater than 0.1 percent (1,000 ppm). The 10 specified phthalates are: • Di-(2-ethylhexyl) phthalate (DEHP); • Dibutyl phthalate (DBP); • Benzyl butyl phthalate (BBP); • Diisononyl phthalate (DINP); • Diisodecyl phthalate (DIDP); • Di-n-octyl phthalate (DnOP); • Diisobutyl phthalate (DIBP); • Di-n-pentyl phthalate (DPENP); • Di-n-hexyl phthalate (DHEP); and • Dicyclohexyl phthalate (DCHP). The specified plastics researched are: • Acrylic resins: Polymethylmethacrylate (PMMA) and Polyacrylonitrile (PAN); • Butadiene-ethylene resins (BER); • Ethylene-butene copolymers (EBC); • Ethylene copolymers: Ethylene vinyl acetate (EVA) and Ethylene vinyl alcohol (EVOH); • Ethylene-propylene monomer (EPM) and Ethylene-propylene-diene monomer (EPDM); • Ionomers (Surlyn®); • Polycarbonate (PC); • Polystyrene (crystal and general-purpose [GPS]), medium-impact (MIPS), and super-high-impact (SHIPS) grades; Styrene-butadiene copolymers (SBC); • Silicone rubber (SR); • Styrene-acrylonitrile copolymers (SAN); and • Styrene-butadiene-styrene rubber (SBS) and styrene-butadiene rubber (SBR). This research was completed in support of CPSC’s work on third party testing burden reduction consistent with assuring compliance. CPSC staff will consider this information in evaluating whether staff could make a recommendation for a Commission determination that one or more of the specified plastics does not contain any of the 10 specified phthalates in concentrations above 0.1 percent; and thus, may not require third party testing to assure compliance with section 108 of the Consumer Product Safety Improvement Act of 2008. This report will be posted on CPSC’s website to keep stakeholders informed of the progress of technical research related to the agency’s regulatory activities. Exposure Assessment: Potential for the Presence of Phthalates in Specified Materials at Concentrations Above 0.1 Percent Task Order 16 Contract Number CPSC-D-12-0001 August 8, 2016 Final Report Prepared by: Toxicology Excellence for Risk Assessment (TERA) University of Cincinnati Contact: Patricia McGinnis [email protected] Bernard Gadagbui [email protected] Jeanelle Martinez [email protected] Jacqueline Patterson [email protected] Melissa Vincent [email protected] Alison Pecquet [email protected] Ann Parker [email protected] Chijioke Onyema [email protected] External Review: Stephen Thiel [email protected] Table of Contents 1 Introduction ........................................................................................................................... 14 1.1 References ..................................................................................................................... 16 2 Literature Review Strategy ................................................................................................... 17 2.1 Tier 1. Universe of Literature ....................................................................................... 18 2.2 Tier 2. Authoritative Secondary Sources (Websites) .................................................... 20 2.3 Tier 3. Literature Searching .......................................................................................... 23 2.4 Tier 4. Gap Searching ................................................................................................... 25 3 Acrylic Resin [Polymethylmethacrylate (PMMA) and Polyacrylonitrile (PAN)] CASRNs: 9011-14-7; 9008-29-1; 25014-41-9 .............................................................................................. 28 3.1 Raw Materials Used in Production of Acrylic Resin.................................................... 28 3.1.1 Raw Materials Used in Making PMMA and PAN ................................................... 28 3.2 Manufacturing Processes used Worldwide to Produce Acrylic Resin .......................... 30 3.2.1 PMMA ...................................................................................................................... 30 3.2.2 Polyacrylonitrile (PAN) ............................................................................................ 31 3.2.3 Processing ................................................................................................................. 32 3.3 Applications for Acrylic Resin in Consumer Products ................................................. 33 3.3.1 Toys and Child Care Articles .................................................................................... 33 3.4 Potential Use of Recycled Materials Containing Phthalate in Production of Acrylic Resin 34 3.5 Potential Phthalate Contamination/Migration............................................................... 36 3.6 References ..................................................................................................................... 36 2 4 Butadiene – Ethylene Resins (EBR) CASRN: 25068-01-3 ................................................ 38 4.1 Raw Materials Used in Production of EBRs................................................................. 38 4.1.1 Raw Materials Used in Making EBR........................................................................ 38 4.2 Manufacturing Processes used Worldwide to Produce EBR ........................................ 38 4.2.1 Processing ................................................................................................................. 39 4.3 Applications for EBR in Consumer Products ............................................................... 39 4.3.1 Toys and Child Care Articles .................................................................................... 39 4.4 Potential Use of Recycled Materials Containing Phthalate in Production of EBR ...... 40 4.5 Potential Phthalate Contamination/Migration............................................................... 40 4.6 References ..................................................................................................................... 40 5 Ethylene-butene (EB) Copolymers CASRN: 25087-34-7, 9019-29-8 ............................... 42 5.1 Raw Materials Used in Production of EB Copolymers ................................................ 42 5.1.1 Raw Materials in Making EB Copolymers ............................................................... 42 5.2 Manufacturing Processes used Worldwide to Produce EB Copolymers ...................... 42 5.2.1 Processing ................................................................................................................. 43 5.3 Applications for EB Copolymers in Consumer Products ............................................. 43 5.4 Potential Use of Recycled Materials Containing Phthalate in Production of EB Copolymers ............................................................................................................................... 43 5.5 Potential Phthalate Contamination/Migration............................................................... 43 5.6 References ..................................................................................................................... 43 6 Ethylene Copolymers [Ethylene Vinyl Acetate (EVA) CASRN 24937-78-8 and Ethylene Vinyl Alcohol (EVOH) CASRN 25067-34-9] ............................................................................ 45 3 6.1 Raw Materials Used in Production of Ethylene Copolymers ....................................... 45 6.1.1 Raw Materials Used in Making EVA and EVOH Copolymers ................................ 45 6.2 Manufacturing Processes used Worldwide to Produce Ethylene Copolymers (EVA and EVOH) ...................................................................................................................................... 46 6.2.1 EVA Copolymers ...................................................................................................... 46 6.2.2 EVOH Copolymer .................................................................................................... 47 6.2.3 Processing ................................................................................................................. 47 6.2.4 Additives – EVA copolymer ..................................................................................... 48 6.2.5 Additives – EVOH copolymer .................................................................................. 48 6.3 Applications for Ethylene Copolymers in Consumer Products .................................... 49 6.3.1 Toys and Child Care Articles .................................................................................... 49 6.4 Potential Use of Recycled Materials Containing Phthalate in Production of Ethylene Copolymers ............................................................................................................................... 49 6.5 Potential
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