Presentation on theme: "Latest Science on the Toxic Flame Retardant – “Chlorinated Tris” (aka TDCPP) Heather M. Stapleton Assistant Professor Duke University Nicholas School of."— Presentation transcript:
Latest Science on the Toxic Flame Retardant – “Chlorinated Tris” (aka TDCPP) Heather M. Stapleton Assistant Professor Duke University Nicholas School of the Environment Durham, NC
Outline 1.Introduction – The history of flame retardants: PBDEs and new use chemicals 2.Background Information a.What regulations govern the use of these chemicals in products? b.What types of products contain flame retardants? c.What are the concerns for exposure to FRs in these products? 3.Research Studies: Identification of New Use FRs: What are the new chemicals being used in polyurethane foam to meet flammability standards? Toxicity of TDCPP: Is TDCPP a neurotoxciant and developmental toxicant? How does its toxicity compare to the pesticide chlorpyrifos? 4.Conclusions/ Discussion
Source: Norén and Meironyté, 2000; Meironyté, : pentaBDE and octaBDE commercial mixtures banned by European Union 2004: US manufacturers discontinued production of pentaBDE and octaBDE 2007: 11 US states banned use of pentaBDE and octaBDE 2010: PentaBDE and OctaBDE commercial mixtures added to Stockholm Convention PBDEs in Swedish Human Milk PBDE Introduction
PBDEs in Human Samples From Around the World Total PBDEs (ng/g lipid) From Hites et al., 2005
Rapidly accumulating in humans and environment Hormonal disruption –Animal exposure studies suggest significant impacts on thyroid regulation and estrogen/androgen pathways –Associations between PBDEs and thyroid hormones (Turyk et al., 2008; Chevrier et al., 2010) and reduced fecundability (Harley et al., 2010) in human population Developmental effects –Irreversible learning/behavioral effects in young animals –Decreased ovarian follicles, sperm counts –Associations between cryptorchidism and PBDEs in male infants (Main et al., 2007) –Associations between PBDE exposure at birth and neurodevelopment in children (Roze et al., 2009; Herbstman et al., 2010), and reduced birth weight (Chao et al., 2007) Cancer? –Structures similar to known carcinogens (PCBs, PBBs) Major Concerns about PBDEs:
Regulations That Govern the Use of FRs U.S. Furniture: California Technical Bulletin 117 California Technical Bulletin 603 Federal Mattress Flammability Standard (CFR 1633) Electronics: Underwriters Laboratory Certifications for Insurance purposes (e.g. UL 746 and -94 V-2 – E&E) Textiles: Children’s Sleepwear (CPSC) Seats in Public Transportation (regulated by specific gov’t agency) Seats and Drapes in Public Buildings (NFPA 701, CA TB 133) Military tarps (Military) Building and Construction: (variable)
What is TB 117? Promulgated by California Bureau of Home Furnishing and Thermal Insulation, within the Department of Consumer Affairs Requires 12-second open flame testing for polyurethane inside furniture Has required the use of large quantities of halogenated flame retardants (FR) Additive FRs used for PUF CA standard affected furniture composition throughout the U.S.
What Type of Products are Treated with Flame Retardants in Your Home? Nursing Pillow Sleep Positioners
Flammability Regulations (Residential = TB 117) High FR Use in Commercial Products (polyurethane foam) Human Exposure Off-Gassing to Air Accumulation in Dust Human Exposure to Flame Retardant Chemicals Diet
Objectives of Study 1.To determine if the following baby products contain a halogenated flame retardant: -car seats, changing tables, portable mattresses, nursing pillows, sleep positioners 2. To determine which flame retardants were found most frequently in these products, and when identified, measure the concentration in the foam; 3. To determine if an X-Ray Fluorescence Analyzer can accurately detect and quantify brominated and chlorinated flame retardants in foam from these baby products Because TB 117 appears to drive the use of FRs in foam containing baby products, we conducted the following study:
Environ. Sci. Tech. 45(12):
Methods -Recruitment letters describing our study were distributed via to colleagues and parent listservs; -Individuals interested in participating mailed a piece of foam (2 cm x 2 cm) to the study team and filled out a short questionnaire; -Foam samples were logged into a database and then split in two (XRF and GC/MS Analysis conducted separately and blind) -All foam pieces were first screened for the presence of a detectable flame retardant (FR) using full scan GC/EI-MS and GC/ECNI-MS -When a FR was positively identified (Mass Spec Database, NIST 2005) a second quantitative analysis was performed on the foam to measure the concentration of the FR in the foam using authentic standards.
Analysis of the Foam Samples Foam Step 2. Sonicate the test tube for 15 min. Step 1. Place a small piece of foam into a test tube with dichloromethane
Gas Chromatograph Mass Spectrometer (GC/MS) Agilent Technologies Model 5975 Step 3. Remove the dichloromethane, filter out the particles, and then inject the extract into a GC/MS*. Samples are run in full scan mode Signals detected are compared against a NIST mass spectral database For commonly known FRs we also now compare to authentic standards. Analysis of the Foam Samples *Some sample extracts also run by LC/MS-MS
Detection of Flame Retardants in Baby Products Product # Samples % with Flame Retardant Car Seat21100 Changing Table Pad1694* Infant Sleep Positioners1553 Portable Mattresses (e.g “Pack-n-play”)1385* Nursing Pillows11100 Baby Carriers (e.g. “Baby Bjorn”)540 *one samples had chemicals in foam, but they were unidentifiable
Flame Retardants in Baby Foam Flame Retardant # of Detects Concentration (mg/g foam) PentaBDE Ʃ TBB and TBPH (Firemaster 550) Triphenyl phosphate and Triaryl phosphates V6/Tris (2-chloro-ethyl) phosphate (TCEP)15Unknown Unknown Cl-OPFR/TCPP6Unknown Tris(1-chloro-2-propyl)phosphate (TCPP) Tris(1,3-dichloro-2-propyl)phosphate (TDCPP) Peaks Unidentified10 No Significant peaks observed11* * Phthalates present at low levels
Flame Retardants in Couch Foam (n=100) Flame Retardant # of Detects PentaBDE18 Ʃ TBB and TBPH (Firemaster 550) 13 Triphenyl phosphate and Triaryl phosphates9** V6/Tris (2-chloro-ethyl) phosphate (TCEP)1 Unknown Cl-OPFR/TCPP0 Tris(1-chloro-2-propyl)phosphate (TCPP)0 Tris(1,3-dichloro-2-propyl)phosphate (TDCPP)44 Peaks Unidentified15 (Preliminary data; Research in Progress) * Similar to tricresyl phosphates
Chlorinated Organophosphates Tris(2-chloroethyl)phosphate (TCEP) Carcinogen Phased out in Europe California Prop 65 list P O O O O Cl Tris(1-chloro-2-propyl)phosphate (TCPP) Replaced TCEP Little toxicity information P O O O O Cl Tris(1,3-dichloro-2-propyl)phosphate (TDCPP) Replaced tris(2,3-dibromopropyl)phosphate in children’s sleepwear in 1977 in US Phased out of use in children’s sleepwear in late 1970s due to mutagenicity (Gold et al. 1978) Probable carcinogen (WHO, US CPSC) In Vitro Neurotoxicity Similar to Chlorpyrifos (Dishaw et al., 2011) P O O O O Cl
How Toxic is TDCPP? Objectives: 1. To determine the toxicity of TDCPP in rat neuronal cells and compare its toxicity to the known neurotoxicant pesticide chloryprifos; (published paper) 2. To determine the toxicity of TDCPP to fish embryos to better understand its potential effects on development (work currently in progress)
Transformed rat neuronal cell line 11 –Higher dosing levels necessary Established in vitro model of neural development 12,13 –Replicates in vivo effects of OP pesticides Mechanisms of toxicity 11. Greene and Tischler Song et al Jameson et al 2006 PC 12 In Vitro Cell Model
Effects on Cell Numbers Dishaw et al., 2011
Effects on Ability of Cells to Grow Properly Dishaw et al., 2011 c
TDCPP is Present in Indoor Environments TDCPP detected in indoor air collected from office buildings in Boston, MA (Webster et al., 2010, geometric mean value of 1.2 ng/m 3) and in indoor air filters from hotels in Japan (Takigami et al 2009) TDCPP measured in dust collected from Boston, MA (Webster et al., 2010) TDCPP concentrations ranging from <20 to 630,000 ppb; average concentrations highest in automobile dust (26,105 ng/g) TDCPP measured in dust collected from Durham, NC (Research in Progress) Range from 416 – 96,810 ppb (average 5980 ppb). Significant associations between TDCPP in house dust and a decrease in free Thyroxine (T4) and an increase in prolocatin (Meeker and Stapleton, 2010)
Children’s Exposure to Flame Retardants in Dust Children are spending more time indoors Indoor environments are often more polluted than outdoor environments Children have a high number of hand-to-mouth contacts
Conclusions (Part 1) Flame retardants (FR) were detected in more than 80% of the baby products tested, and all but one was halogenated; TDCPP, and Firemaster 550, appear to be the dominant FRs used in polyurethane foam in products sold in the U.S. (both in baby products and couches); TDCPP is as potent a neurotoxicant as the pesticide chlorpyrifos in rat neuronal cells in vitro; TDCPP exposure in zebrafish embryos affects survivorship and induces developmental abnormalities, similar to chlorpyrifos. TDCPP is present in indoor air and dust in almost all homes in the U.S. Exposure to children is higher than adults from dust exposure.
What Industry Will Try to Tell You The European Union Risk Assessment Demonstrates that TDCPP is Safe Response: This risk assessment lacked any recent measured data on TDCPP; nor did it evaluate children’s exposure to TDCPP from use of baby products Removing TDCPP as a flame retardant will decrease fire safety and put more children in danger Response: This is not true. Suitable replacements are available to replace TDCPP in foam. The EPA conducted an alternatives assessment for polyurethane foam in 2005
A Daycare Infant Mattress Certified to Meet CFR 1633 (Federal Flammability Open Flame Standard) Foam removed for analysis and Identification of Flame Retardant
Acknowledgements Research funding provided by National Institutes of Health (Grant number R01 ES016099) Collaborators and Colleagues: Dr. Arlene Blum, Dr. Susan Klosterhaus, Rebecca Anthopolos (Duke University), Deborah Watkins (Boston University), Saskia van Bergen Laboratory Group: Sarah Eagle, Smriti Sharma, Dr. Craig Butt, Dr. Ellen Cooper, Pamela Noyes (PhD student), Elizabeth Davis (PhD student), Simon Roberts (PhD student), Laura Dishaw (PhD student), Alex Keller (undergraduate), Study Participants Dr. Marie Lynn Miranda Duke Univ. Dr. Thomas Webster Boston Univ.