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 27708

Email: heather.stapleton@duke.edu

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www.environmentcalifornia.org

Outline1. Introduction – The history of flame retardants: PBDEs and new use

chemicals

2. Background Informationa. 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

Year

1970 1975 1980 1985 1990 1995 2000 2005

PB

DE

(n

g/g

lip

id)

0

1

2

3

4

Source: Norén and Meironyté, 2000; Meironyté, 2002

2003: 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

Total PBDE concentrations in human blood, milk and tissue (in ng/g lipid) shown as a function of sampling year.

1970 1980 1990 2000 2010

To

tal

PB

DE

co

nc.

(p

pb

lip

id)

0.01

0.1

1

10

100

1000

North America Europe Japan

PBDEs in Human Samples From Around the WorldTo

tal

PB

DE

s (n

g/g

lip

id)

1970 1980 1990 2000 2010

0.1

1

10

100

1000

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 flameretardant:

-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): 5323-5331

Methods- Recruitment letters describing our study were distributed via email 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.

Foam Samples Collected (n=101)

Baby Product# of

Samples

Car Seats 21

Changing Table Pads 16

Sleeping Wedge/Positioner 15

Portable Mattresses 13

Nursing Pillows 11

Baby Carriers 5

Rocking Chairs 4

High Chairs 3

Infant Bath Sling 2

Baby Walkers 2

Misc. Samples: Stroller, bath toy, baby tub mat, Bumbo chair, toilet seat

Analysis of the Foam Samples

Foam

Step 2. Sonicate the test tube for 15 min.Step 1. Place a small piece of foaminto 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 injectthe 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

Time (min)

8 10 12 14 16 18 20 22 24

Res

po

nse

0

2e+7

4e+7

6e+7

8e+7

1e+8

PentaBDE

BDE 99

BDE 153

BDE 47

BDE 154

BDE 100

Detected in 4 samples: - Car Seat (2) - Portable Mattress - Rocker

Time (min)

8 10 12 14 16 18 20 22 24

Re

sp

on

se

0

2e+7

4e+7

6e+7

8e+7

1e+8

Firemaster® 550TPP

Tri-aryl phosphates

Detected in 17 Samples: - Car Seat (8) - Portable Mattress (4) - Changing Table Pad (4) - Rocking Chair (1)

Time (min)

8 10 12 14 16 18 20 22 24

Res

po

nse

0

2e+7

4e+7

6e+7

8e+7

TDCPPTris (1,3-dichloroisopropyl) phosphate

Detected in 36 Samples: - Car Seat (11) - Changing Table Pad( 8) - Sleeping Wedge (6)- Portable Mattress (3)- Baby Walker (2)- High Chair (2) - Rocking Chair (1) - Baby Carrier (1) - Nursing Pillow (1) - Infant Bath Sling (1)

Time (min)

10 15 20 25

Res

po

nse

0

1e+7

2e+7

3e+7TCEPTris (2-chloroethyl) phosphate

Detected in 14 Samples: - Nursing Pillow (9) - Infant Bath Sling (2) - Baby Carrier (1) - Sleeping Wedge (1) - Portable Crib (1)

*Relatively low response of TCEP……and“bump” suggests degradation…….

2,2-bis(chloroethyl)triethylene bis[bis(2-chloroethyl)phosphate] “V6”

TCEP

LC/MS-MS for TCEP and “V6”

TCEPV6

TCEP V6

MS-MS (Agilent 6410B triple quadrupole) Positive electrospray ionization Gas: 350°C ; 10 L/min Nebulizer: 40 psi Capillary: 4000 V(+) MS2 Scans: 250-620 m/z; fragmentor: 80V

RT: 0.00 - 10.00

0 1 2 3 4 5 6 7 8 9 10

Time (min)

0

20

40

60

80

100

Rel

ativ

e A

bund

ance

7.03

5.61

9.148.96 9.27

6.82 7.67 8.898.296.394.283.64 5.364.840.740.52 1.871.06 2.20 3.212.64

NL:3.36E7

TIC F: FTMS + p ESI Full ms [250.00-2000.00] MS CABF17

635 640 645

m/z

0

20

40

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100

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Relat

ive A

bund

ance

638.9741

640.9712

636.9769

642.9682

644.9649632.9392

638.9747

640.9717

636.9776

642.9688

644.9658

NL:5.89E5

CABF17#1771 RT: 7.03 AV: 1 T: FTMS + p ESI Full ms [250.00-2000.00]

NL:2.96E5

C17H33O8Cl 6P 2: C17H33O8Cl 6P 2

pa Chrg 1

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2,2-bis(chloromethyl)propane-1,3-diyl tetrakis(1-chloropropan-2-yl) bis(phosphate)

Tris (1-chloro-2-propyl)phosphate

Observed MS

Predicted MS

LC/HRMS Spectra of New Cl-OPFR

TCPP

Detection of Flame Retardants in Baby Products

Product#

Samples% with Flame

Retardant

Car Seat 21 100

Changing Table Pad 16 94*

Infant Sleep Positioners 15 53

Portable Mattresses (e.g “Pack-n-play”) 13 85*

Nursing Pillows 11 100

Baby Carriers (e.g. “Baby Bjorn”) 5 40

*one samples had chemicals in foam, but they were unidentifiable

Flame Retardants in Baby Foam

Flame Retardant

# of Detects

Concentration (mg/g foam)

PentaBDE 4 38 - 53

ƩTBB and TBPH (Firemaster 550) 17 6 - 43

Triphenyl phosphate and Triaryl phosphates 1 1 - 10

V6/Tris (2-chloro-ethyl) phosphate (TCEP) 15 Unknown

Unknown Cl-OPFR/TCPP 6 Unknown

Tris(1-chloro-2-propyl)phosphate (TCPP) 16 0.02 - 14

Tris(1,3-dichloro-2-propyl)phosphate (TDCPP) 36 0.05- 124

Peaks Unidentified 10

No Significant peaks observed 11*

* Phthalates present at low levels

Flame Retardants in Couch Foam (n=100)

Flame Retardant# of

Detects

PentaBDE 18

ƩTBB and TBPH (Firemaster 550) 13

Triphenyl phosphate and Triaryl phosphates 9**

V6/Tris (2-chloro-ethyl) phosphate (TCEP) 1

Unknown Cl-OPFR/TCPP 0

Tris(1-chloro-2-propyl)phosphate (TCPP) 0

Tris(1,3-dichloro-2-propyl)phosphate (TDCPP) 44

Peaks Unidentified 15

(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

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Tris(1-chloro-2-propyl)phosphate (TCPP)• Replaced TCEP

• Little toxicity information

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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)

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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 betterunderstand its potential effects on development (work currently in progress)

• Transformed rat neuronal cell line11

– Higher dosing levels necessary• Established in vitro model of neural development12,13

– Replicates in vivo effects of OP pesticides

• Mechanisms of toxicity

11. Greene and Tischler 197612. Song et al 199813. Jameson et al 2006

PC 12 In Vitro Cell Model

Control

50 µ

M C

PF

10 µ

M T

DCPP

20 µ

M T

DCPP

50 µ

M T

DCPP

4 Day Exposure

Control

50 µ

M C

PF

10 µ

M T

DCPP

20 µ

M T

DCPP

50 µ

M T

DCPP

DN

A (

mg

/dis

h)

0

20

40

60

80

1006 Day Exposure

aa

b

ba

b

c

Effects on Cell Numbers

Dishaw et al., 2011

Dopaminergic

Control

50 µ

M C

PF

10 µ

M T

DCPP

20 µ

M T

DCPP

50 µ

M T

DCPP

TH

(n

mo

l/m

g D

NA

/h)

0

50

100

150

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350

ba

a,b

Dopaminergic

Control

50 µ

M T

DCPP

50 µ

M T

CEP

50 µ

M T

CPP

50 µ

M T

DBPP

TH

(n

mo

l/m

g D

NA

/h)

0

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aa

Effects on Ability of Cells to Grow Properly

Dishaw et al., 2011

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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/m3) 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

http://www.theage.com.au/articles/2006/05/02/1146335739915.html

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 toMeet CFR 1633 (Federal FlammabilityOpen 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 MirandaDuke Univ.

Dr. Thomas WebsterBoston Univ.