americanchemistry.com®

 700 Second St., NE | Washington, DC 20002 | (202) 249.7000 

November 26, 2013 

Submitted via Electronic Mail 

Katherine Sleasman 

Office of Pollution Prevention and Toxics 

Chemical Control Division, Existing Chemicals Branch 

1200 Pennsylvania Ave. NW

EPA East, Room 4410G 

Sleasman.Katherine@epamail.epa.gov

Re: Toluene Diisocyanate (TDI) And Related Compounds Action Plan, 

RIN 2070-ZA15, April 2011

Dear Ms. Sleasman, 

The American Chemistry Council Diisocyanates Panel (“Panel”)1is pleased to have the 

opportunity to submit information to the Environmental Protection Agency related to the Toluene 

Diisocyanate (TDI) And Related Compounds Action Plan issued in April 2011. The purpose of 

this document is to address potential Agency questions regarding TDI in flexible polyurethane 

foam (FPF) and to establish, based on the published data, that FPF does not contain unreacted 

TDI that can be transferred via the air or by direct contact with the product to a consumer. 

Therefore, consumer products such as mattresses made of FPF, when used as intended, are not 

expected to expose the consumer to unreacted TDI. 

In the TDI Action Plan issued in April 2011, EPA stated that the Agency “intends to initiate 

rulemaking under TSCA section 5(a)(2) for a SNUR, designating the use of uncured TDI and its 

related polyisocyanates in a consumer product as a new use.” EPA also stated: “[t]his Action 

Plan focuses on the potential health effects that may result from exposures to the consumer or 

self-employed worker while using products containing uncured (unreacted) diisocyanates (e.g., 

spray applied sealants and coatings) or incidental exposures to the general population while such 

products are used in or around buildings, including homes or schools.” EPA further

stated: “[o]ther polyurethane products, such as mattresses, pillows, and bowling balls, are 

considered completely cured products before they are sold. Completely cured products are fully 

reacted and therefore are considered to be inert and non-toxic (Krone & Klinger, 2005). This 

Action Plan focuses on concerns for unreacted, uncured products.” [emphasis added]

However, in a recent presentation you made on behalf of EPA at the September 2013 

Polyurethanes Technical Conference, the presentation stated that EPA will “initiate a rulemaking 

under TSCA section 5(a)(2) for a Significant New Use Rule (SNUR) designating certain uses of 

 

1 The Panel includes U.S. manufacturers of TDI and/or MDI: BASF Corporation, Bayer MaterialScience, The Dow 

Chemical Company, and Huntsman Corporation.
Page 2 of 15

TDI in a consumer product as a new use requiring prior notice to the Agency.” Based on what 

was presented at the September 2013 Conference, it appears that EPA is now expanding the

focus from products containing unreacted isocyanates to include finished and cured consumer 

products. If this is indeed the case, it could be a significant departure from EPA‟s original intent 

outlined in the April 2011 TDI Action Plan. 

The following bullets summarize the Panel‟s general comments based on the published data

regarding TDI in FPF. A number of studies leading to these conclusions are described in greater 

detail in the attached Q&A document.

 No “free TDI” has been detected in emission testing of commercial FPFs.

 

 There have been publications using extraction testing protocols that reported values 

attributed to “free TDI” in commercial FPFs. Concurrent extraction/derivitization 

protocols cannot discriminate between “free TDI”, dimer, biuret or allophanate. In 

addition, these extraction protocols themselves are not considered to be representative 

of consumer use. 

 Using conservative, accepted risk analysis protocols, no risk of consumer exposure 

has been demonstrated for the use of TDI in FPF.

 Since the odor threshold range for TDI is generally accepted as 50-100 ppb (parts per 

billion), it is extremely unlikely that “free TDI” could contribute to consumer odor 

concerns. 

 Countless polyurethane products made possible with diisocyanates chemistry are 

important to America‟s economy, particularly in the FPF sector. Because FPF 

production uses TDI, the potential economic and job impacts are paramount. 

The Panel urges the Agency to consider our comments as it determines next steps with the TDI 

Action Plan. The Panel looks forward to meeting with EPA to discuss developments under the 

TDI Action Plan. In the meantime, please contact me at (202) 249-6721 or sahar_osmansypher@americanchemistry.com if you have any questions or need additional information. 

Sincerely,

Sahar Osman-Sypher 

Sahar Osman-Sypher

Director, Diisocyanates Panel 

cc: Wendy Cleland-Hamnett 

Leslie Cronkhite 

Maria Doa

Attachment: Q&A on TDI from Flexible Polyurethane Foam in Bed Mattresses
Page 3 of 15

ATTACHMENT:

Q&A on TDI from Flexible Polyurethane Foam in Bed Mattresses

Summary

The purpose of this document is to address potential Agency questions and to establish, 

based on the published data, that flexible polyurethane foam (FPF) does not contain unreacted 

TDI that can be transferred via the air or by direct contact with the product to a consumer. 

Therefore, consumer products such as mattresses made of FPF, when used as intended, are not 

expected to expose the consumer to unreacted TDI. A number of studies leading to these 

conclusions are briefly summarized below and described in greater detail in the Q&A document 

that follows this summary. 

Reports of “free TDI” being extractable and measured in foam samples even several years postproduction were followed by rigorous analytical investigations to improve understanding of 

these findings. These subsequent analytical studies confirmed that measurable amounts of TDI 

can be extracted from FPF. Using several combinations of extraction solvent/derivatizing agents 

and physical extraction procedures, the pattern of TDI measurements from sequential extractions 

of the same foam sample was best explained by mechanisms other than the presence of “free” 

TDI. The non-homogeneous nature of FPF matrix is expected to contain chemical moieties such 

as TDI dimers, biurets and allophanates. The presence of such chemical compounds being 

extracted by the solvents also can lead to a subsequent reaction with the amine-based 

derivatizing agent to yield false positive results for “free” TDI. This circumstance does not 

allow for a definitive distinction between any extracted TDI monomer and an analytical signal 

derived from a dimer, biuret or allophanate. Studies to date reporting the presence of “free TDI”

in FPF are encumbered by the necessary use of a solvent for the extraction phase, followed by a 

derivatizing agent, and thus do not lead to definitive results. Another set of investigators 

followed a different approach - a more direct assessment of hypothetical consumer exposure and 

potential health implications.

A risk assessment of a simulated use by a consumer of a FPF product was considered. The 

simulation involved a consumer sleeping on a mattress made of FPF. The determination of 

exposure to the individual relied on experiments measuring the emission of TDI from a sample 

of FPF and separate measurements simulating direct skin contact. The tests results indicated no 

measureable emission or migration of TDI from the FPF samples tested. Complementary 

information required for a risk assessment is an estimate of hazard. The known health effects 

associated with TDI were used for this assessment. Further, a number of conservative, (health 

protective) assumptions were used such as direct contact of a person‟s skin to a foam mattress 

with no intervening fabric. A comparison of hypothetical exposure to thresholds not expected to 

induce the known health hazards of TDI resulted in margins of safety ranging from 200 to 3 

million, well over the acceptable margin of safety of 1. 

 

In conclusion, a generalization of these findings from the analytical chemistry and risk 

assessment perspectives indicates that a realistic scenario depicting the use of a mattress (a 

relatively large FPF article) does not support a TDI-based health risk to the general public.
Page 4 of 15

Questions and Answers

Q1. Is there “free TDI” in the flexible polyurethane foam used in bed mattresses?

A1. Once the foam has been manufactured and incorporated into mattresses for sale to 

consumers, TDI monomer is no longer available. Scientists have tried to remove TDI 

from the foam using air extraction and solvent extraction. There was no TDI 

measured with air extraction. Solvent extraction sometimes results in measurable TDI 

readings. Scientists knowledgeable about polyurethane foam chemistry reviewed the 

findings, and concluded that polyurethane foam may be broken down by the 

extraction solutions used and thus contribute to the TDI readings measured.

Discussion

Understanding the answer to this question necessarily involves a discussion of the nature of 

flexible polyurethane foam (FPF), the various techniques one might use to assess the 

presence of “free TDI” in it, and the purpose for which the question was asked. 

Isocyanate groups in foam - The FPF used in mattresses is made from the reaction of TDI 

with polyols (long chained polymers similar to glycols) and water in the presence of 

catalysts (a mixture of amines) and other components (auxiliary blowing agents, flame 

retardants, surfactants, colorants). Residual levels of TDI in freshly-produced FPF would 

be expected, but will be reduced to very low levels after the post production cure period 

[Dieterich et al., 1993]. As the polyurethane polymer chain develops, it also is possible 

that some unreacted “isocyanate groups” (i.e., -N=C=O) will remain attached to the 

polymer chain. These “bound isocyanate groups” can be measured on polymer chains near 

the foam surface by infrared techniques [Van Gheluwe et al., 1987] or visualized by 

introducing colorimetric reagents that react with isocyanate groups into the foam [Krone et 

al., 2003].

Measuring TDI in foam - Only a few studies report attempts to evaluate the level of “free 

TDI.” One of two approaches were taken in these studies: (1) emission to air [Hugo et al.,

2000], or (2) extraction with organic solvent [Conte and Cossi, 1981; Jedrzejczak and 

Gaind, 1993; Krone et al., 2003; Gagné et al., 2003; Vangronsveld et al., 2013a]. Key 

aspects of these studies are summarized in Table 1 and the study results are discussed in the 

paragraphs following.

In the emission study, emission testing of a commercial foam three days post-production by 

passing air through the foam matrix showed no detectable TDI emitted (detection limit ~ 

0.1 ppb v/v in air, which corresponded to 0.4 ng/g FPF). 

The first four studies which determined solvent extractable TDI varied in the solvent used, 

severity of extraction conditions, and the analytical technique used. Extractable TDI 

results from two of these four studies [Conte and Cossi, 1981; Jedrzejczak and Gaind, 

1993] were below detection limits for FPF samples that were older than the usual one to 

three-day post production curing period. One of the two studies that did detect extractable 

TDI in FPF samples beyond the post production curing period was the study with the 

lowest detection limits [Gagné et al., 2003]. For two of the three FPF samples in the study 
Page 5 of 15

very low levels (3-17 ng/g FPF) that would have been below the detection limits of the 

other studies were reported, and no detectable TDI was reported in the third FPF sample. 

The remaining study [Krone et al., 2003] is notable for reporting detectable quantities of 

extractable TDI (3-20 μg/g FPF) in all three FPF samples tested, which ranged in age from 

1-30 years.

Because of the variable results reported in the literature, the fifth solvent extraction study 

listed in Table 1 was carried out to compare different solvents and derivatization agents in 

determining extractable TDI from an FPF that was expected to contain residual TDI 

monomer (made with a high ratio of TDI to polyol)[Vangronsveld et al., 2013a]. The study 

looked at 6 solvent / derivatization agent combinations with a single representative foam. 

Results for total extractable TDI varied by a factor of 7, and showed unusual behavior with 

some solvents (e.g., increasing extractable TDI with successive serial extractions).

False positive TDI measurements from extractions – The behavior seen in Vangronsveld 

et al., 2013a results indicates that more than simple solvent extraction was occurring. 

Further insight can be gained from a detailed consideration of the chemistry of FPF 

formation. 

In polyurethane flexible foam production, three poorly-miscible liquids are dispersed into 

each other: TDI, water and polyether polyol (with a mean molecular weight about 3000 –

6000 g/mol). In the beginning of the reaction, there are three different liquid phases [Hager 

et al., 1994]. When the consumption of isocyanate functional groups reaches about 50%, 

solid structures start to precipitate, and the further reaction of isocyanate groups proceeds 

with an initial half-life of about three days [Elwell et al., 1994; Hauptmann et al., 1981]. 

The final flexible foam has three different solid phases: hard segments, soft segments, and 

“urea balls.” Hard segments are formed by urethane structures which are cross-linked 

hydrogen bonds from the one urethane-group N-H to the next urethane group C=O, and 

soft segments are made up of the polyols chains [McClusky et al., 1994]. Urea balls are a 

consequence of the poor miscibility of TDI in water mentioned earlier: TDI droplets in 

water rapidly form a polyurea shell that slows down further reaction of the TDI core, 

similar to reactions reported at the interphase between TDI and water [Brochhagen and 

Grieveson, 1984; Yakabe et al., 1999]. As a result, some unreacted TDI may remain 

trapped in the polyurethane foam structure after the initial formation reaction. Since TDI is 

a reactive molecule, this residual TDI has a high likelihood of undergoing further reactions. 

Reaction with ambient moisture can lead to formation of more polyurea, but reaction with 

the polyurea already present may also form dimers [Arnold et al., 1957], biurets [Joel et al.,

1982] and allophanates [Lapprand et al., 2005]. See Figure 1 below.

The hard segments and urea balls present in FPF can be swollen by strong polar solvents 

such as dimethylformamide (DMF) and dimethyl sulfoxide (DMSO)[Armistead et 

al.,1988], thus providing amine derivatizing agents better access to residual unreacted TDI 

trapped in these structures, as well as to the dimers, biurets and allophanates present. 

Dimers, biurets and allophanates also react with amines, giving the same derivatives as 

“free TDI.” Dimers react comparatively rapidly [Saunders and Hardy, 1953]. The reaction 

rate of biurets and allophanates with secondary amines increases directly with the polarity 

of the organic solvent used and with temperature [Joel and Weiler, 1980]. 
Page 6 of 15

Polar organic solvents, therefore, have two effects when used in methods for the 

determination of residual TDI in flexible foam. First, they make any entrapped TDI more 

accessible for the reaction with the amine derivatizing agent. Second, they accelerate the 

reaction of biurets and allophanates with the same derivatizing agent, producing the same 

derivative as with TDI. Because of these effects, measurements of TDI derivatives 

resulting from polar organic solvent extraction methods actually indicate the sum of any 

residual TDI monomer (“free TDI”), and TDI derived from dimers, biurets and 

allophanates by reaction with the derivatizing agent.

Production of TDI from cleavage of biurets and allophanates was further investigated in 

another study [Schmidtkunz, 2012]. In this work, the reaction of a TDI biuret containing 

no TDI monomer with a solution of each of three isocyanate derivatizing agents (two 

secondary amines and ethanol) over a period of 96 hours showed detectable levels of 2,4-

TDI derivative which increased steadily over the course of the experiment for the two 

amines, but not for ethanol. The author concludes that amines react with biurets and 

allophanates to produce the same analyte as TDI does while alcohols do not. The author 

further comments that it is well known in the literature that biurets and allophanates are 

prone to cleavage by nucleophiles (such as amine derivatizing agents).

Consumer exposure to TDI bioavailable from foam – In conducting an exposure risk 

assessment for a component in a product, the first step is measuring or estimating the likely 

exposure level. An exhaustive extraction of the component out of the product is sometimes 

used to provide an extreme case, maximum estimate of potential exposure. However, a 

more realistic exposure estimate can be made by conducting experiments that simulate the 

most challenging case of actual use conditions. This is the approach taken, for example, by 

the U.S. Food and Drug Administration when evaluating polymers intended for food 

contact use. Polymer formulations intended for use in food containers are subjected to 

immersion in “food simulating solvents” (e.g., 10-50% ethanol in water, corn oil) and the 

highest anticipated processing temperatures to see how much monomer is available to 

migrate into the food [US FDA, 2007]. 

Because of the information on exhaustive solvent extraction with TDI and FPF discussed 

earlier, such exposure simulating tests to measure TDI available from FPF for consumer 

exposure have been developed [Vangronsveld et al., 2013b]. The testing involves 

measuring the emission of TDI to air from an FPF test sample (simulating consumer 

inhalation exposure) and the migration of TDI to a surface in contact with the foam surface 

(simulating consumer dermal exposure) over a period of 8-24 hours. In the study, a 

representative foam was tested that had detectable levels of solvent-extractable TDI; 

emission and migration testing of the FPF showed no detectable TDI at detection limits of 

0.005 ng/cm2FPF surface for emission testing and 0.16 ng TDI/cm2FPF contacted for 

migration testing.
Page 7 of 15

Table 1. Extractable TDI from flexible polyurethane foam: comparison of studies in the literature 

Study Extraction type /

Analysis description

Extracted TDI found

(μg TDI/g foam)

Detection limit

(μg TDI/g foam)

Hugo et al. air extraction /

amine derivatization & HPLC-UV

ND* 0.0004

Conte and Cossi,

1981

solvent extraction(o-dichlorobenzene)/

GC-FID

ND 5000

Jedrzejczak and Gaind, 

1993

solvent extraction (methanol)/

alcohol derivatization & GC-NCI-MS

ND 0.01

Krone et al.,

2003

solvent extraction (dimethyl sulfoxide [DMSO])/

amine derivatization & HPLC-UV/FL

3000 – 20,000 3

Gagné et al.,

2003

solvent extraction (toluene)/

amine derivatization & HPLC-CIS-MS/MS

ND - 17 0.0001

Vangronsveld et al.,

2013a

solvent extraction (toluene, DMSO, 

dichloromethane, ethanol)/

alcohol or amine derivatization & 

HPLC-ESI-MS/MS

660-4500 10-50

*ND – none detected at detection limit listed
Page 8 of 15

Figure 1. Reactions consuming free TDI in flexible foams. Formation of 

dimers (1), biurets (2) and allophanates (3) 

 
Page 9 of 15

Q2. What about reports by some researchers of “free TDI in 30-year old foam”?

A2. There is only one report of “free TDI in 30-year old foam” in the literature [Krone et 

al., 2003]. Since the isocyanate groups on TDI are quite reactive, they would be 

expected to react with water in the air over a 30-year timeframe. Scientists 

knowledgeable about polyurethane foam chemistry reviewed the findings and 

concluded that the TDI detected from the foam probably resulted from break down of 

the foam by the extraction solutions used.

Discussion

As noted in the answer to Q1 above, there are several studies in the literature reporting 

attempts to determine TDI in foam by solvent extraction. Two of these studies detected no 

extractable TDI, one reported very low levels (below the detection limit of the first two 

studies), and one compared different extraction solvents and derivatizing agents using a 

foam produced with the intention of having measureable levels of residual TDI. Krone et 

al. is notable for reporting the highest extractable TDI levels of the four and also for 

reporting finding extractable TDI in foam as old as 30 years old. 

Residual levels of TDI in freshly-produced FPF would be expected, but will be reduced to 

very low levels after the post production cure period [Dieterich et al., 1993]. As the 

polyurethane polymer chain develops, it is also possible that some unreacted “isocyanate 

groups” (i.e., -N=C=O) will remain attached to the polymer chain. These “bound 

isocyanate groups” can be measured on polymer chains near the foam surface by infrared 

techniques [Van Gheluwe et al., 1987] or visualized by introducing colorimetric reagents 

that react with isocyanate groups into the foam as done by Krone et al. However, such 

“bound isocyanate groups” are not available for inhalation or dermal absorption by 

consumers since they are connected to the polymer matrix itself. Van Gheluwe observed 

that the bound isocyanate groups decline slowly over time as a result of reaction with 

atmospheric moisture diffusing into the foam, but reach a steady state value about a week 

after foam production. 

Extractable TDI from foam was reported by Krone et al. both qualitatively using 

colorimetric surface wipes treated with a reagent that reacted with isocyanate groups to 

give a red color, and quantitatively by extraction of foam samples with DMSO and an 

amine derivatizing agent after they had been frozen with dry ice and ball-milled. As 

described in considerable detail in the answer to Q1 above, FPF contains species which are 

known to undergo cleavage reactions with nucleophiles (such as the amine derivatizing 

agent used) to yield TDI. In addition, polar solvents such as DMSO have been shown to 

accelerate these reactions [Joel and Weiler, 1980]. Also, the manufacturer of the 

colorimetric surface wipes specifies wetting the surface to be wiped with mineral oil to 

promote transfer of isocyanate species from the surface to the wipe. In the Krone et al. 

study, the authors instead used acetone, a polar solvent, in order to transfer the colorimetric 

reagent into the foam to visualize polymer-bound isocyanate groups. As with DMSO, 

acetone would be expected to promote false positive isocyanate readings on the wipe from 

the foam component cleavage reactions described above. 
Page 10 of 15

From the above considerations, it is highly likely that the extractable TDI reported by 

Krone et al. from 30-year old consumer foam are false positives resulting from the action 

of the extraction and derivatization system on species known to be present in the foam. 

Additionally, the aggressive workup and extraction procedures used in the quantitative 

determination do not represent the situation encountered by consumers in actual use of 

polyurethane foam articles. 

Q3. Has anyone assessed the health risk from exposure to TDI for people who sleep on a 

polyurethane mattress?

A3. Yes. Based on measurements of emission and migration of TDI from flexible 

polyurethane foam [Vangronsveld et al., 2013a], a risk assessment for a person 

sleeping for a lifetime on a bare foam mattress has been published [Arnold et al.,

2012]. The risk assessment shows that sleeping on a polyurethane foam mattress does 

not pose any health risks related to TDI exposure.

Discussion

As discussed in the earlier question related to TDI in flexible polyurethane foam (Q1), the 

most appropriate exposure measurements to use as a starting point for risk assessment are 

those which represent the upper-bound values for exposure in actual use conditions. 

Emission to air from foam and migration to a surface in contact with foam are such “upperbound real” exposure measurements for the use scenario of sleeping on a mattress. In their 

study, Vangronsveld et al. tested a representative foam that had detectable levels of 

solvent-extractable TDI; emission and migration testing of the foam showed no detectable 

TDI at detection limits of 0.005 ng/cm2foam surface for emission testing and 0.16 ng 

TDI/cm2foam contacted for migration testing.

Since these results were below detection limits, Arnold et al. began by assuming a value of 

50% of the detection limit value from the Vangronsveld et al. study as the basis for 

calculating the exposure level for risk assessment. The parameters of the exposure scenario 

model (e.g., hours of exposure, room size, mattress size, room ventilation rate) were 

established using widely-accepted values where available. By applying the TDI emission 

and migration values to the exposure scenario model, the authors were able to calculate 

inhalation and dermal exposure concentrations. They then established benchmarks for key 

non-cancer toxicological endpoints (i.e., sensitization, irritation, respiratory tract effects). 

Dividing the respective non-cancer toxicological benchmarks by the calculated inhalation 

and dermal exposure concentrations, the authors calculated a “margin of safety” for each 

benchmark. The margins of safety ranged from 200 to 3 million, well over the target 

margin of safety of 1. Although available data indicate that TDI is not a carcinogen [Prueitt 

et al., 2013], a theoretical total excess cancer risk of 1x10-7 was calculated, which is at least 

an order of magnitude below the typical excess cancer range targeted by regulatory 

agencies (1x10-6to 1x10-4). Based on this assessment, the authors conclude that sleeping 

on a PU foam mattress for a lifetime does not pose TDI-related health risks to consumers.

In order to assist flexible foam manufacturers in conducting such a risk assessment on their 

range of foam products, an information package is available that includes the procedures 
Page 11 of 15

for conducting emission and migration testing and calculation spreadsheets for determining 

the margin of safety of the results [Spence, 2012].

Q4. New bed mattresses sometimes have a noticeable odor; if I smell an odor does it mean 

I’m being exposed to TDI?

A4. The odor is not from TDI. 

Discussion

While the FPF used in mattresses is made from the reaction of TDI, in addition to polyols 

(long chained polymers similar to glycols) and water in the presence of catalysts (a mixture 

of amines) and other components (auxiliary blowing agents, surfactants, colorants), the 

detected odors are not from TDI. This statement can be made because the odor threshold 

range for TDI is generally accepted as 50-100 ppb (parts per billion) [Allport et al., 2003] 

and investigations of TDI emission from mattresses conducted by Battelle for the 

California Air Resources Board detected no TDI emissions at a detection limit of 0.14 ppb 

[Kelly et. al., 1999]. Additional support for the lack of TDI emissions from the FPF used 

in mattresses is the emission study noted in the answer to Q1 above [Hugo et. al., 2000] 

where no TDI emissions to air from such a foam were detected at a detection limit of 0.1 

ppb.

Economic Impact of TDI in the Polyurethanes Industry 

Countless polyurethane products made possible with diisocyanates chemistry are important to 

America‟s economy, particularly in the furniture and bedding, building and construction, and 

transportation sectors. Diisocyanates chemistry can help consumers and businesses save money 

through improved energy efficiency and performance of a wide range of products that use 

polyurethane materials. 

Here are a few facts regarding the importance of TDI to our economy. In 2012, United States 

demand for TDI was at 478 million pounds. Flexible foam slabstock production consumed the 

majority of that demand at 325 million pounds (68%), followed by flexible foam molded at 75 

million pounds (16%). See Table 2 for U.S. TDI demand by product type. Within the flexible 

foam slabstock production, the mattress sector consumes the majority of TDI at 127 million 

pounds (39%), followed by the furniture sector at 69 million pounds (21%). See Table 3 for U.S.

flexible foam slabstock TDI consumption [CPI, 2013]. 

To meet this demand, production of TDI in the United States employs thousands of workers in 

facilities across the nation. When you consider that polyurethane production uses TDI, the 

potential economic and job impact becomes even more significant. The polyurethanes industry 

operates in 935 locations in the United States, directly generating $19.7 billion in output and 

37,700 jobs. Indirectly, the polyurethanes industry supports an additional $40.1 billion in output 

and supports nearly 165,000 additional jobs. In total, the polyurethanes industry supports about 

202,600 jobs and $59.9 billion in output. In addition, polyurethane products are used in 

industries generating $245.5 billion in output and employing nearly 1 million workers [ACC, 

2012].
Page 12 of 15

Table 2: U.S. Demand for TDI by Product Type, 2012 (Mlbs)

Table 3: U.S. Flexible Foam Slabstock TDI Consumption, 2012 (Mlbs)

Flexible Foam 

Slabstock , 325, 68%

Flexilbe Foam 

Molded, 74.7, 16%

Coatings , 35.3, 7%

Binders , 5.8, 1%

Elastomers, 12.3, 3%

Adhesives, 

25.1, 5%

Flexible Foam

Slabstock

Flexilbe Foam Molded

Coatings

Binders

Elastomers

Adhesives

Furniture, 69.3, 21%

Transportation , 

46.4, 14%

Bedding - Mattress, 

126.6, 39%

Bedding - Others, 

14.7, 5%

Packaging, 9.1, 3%

Textiles & Fibers, 

10.3, 3%

Foam Scrap , 

35.2, 11%

Others , 12, 4%

Furniture

Transportation

Bedding - Mattress

Bedding - Others

Packaging

Textiles & Fibers

Foam Scrap

Others
Page 13 of 15

REFERENCES 

Allport, D. C., Gilbert, D. S., and Outterside, S. M. (Eds.) (2003). 'MDI and TDI: safety, health 

and the environment. A source book and practical guide'. Wiley, Chichester. (ISBN 0-471-

95812-3). pp. 36.

American Chemistry Council (2012). The Economic Impact of the Polyurethanes Industry in 

2010. Economics & Statistics Department. 

http://polyurethane.americanchemistry.com/Resources-and-Document-Library/TheEconomic-Impact-of-the-Polyurethanes-Industry-in-2010.pdf

Armistead, J. P., Wilkes, G. L., and Turner, R. B. (1988). Morphology of water-blown flexible 

polyurethane foam. J.Appl.Polym.Sci., 35, (3), 601-29.

Arnold, S. M., Collins, M. A., Graham, C., Jolly, A. T., Parod, R. J., Poole, A., Schupp, T., 

Shiotsuka, R. N., and Woolhiser, M. R. (2012). Risk assessment for consumer exposure to 

toluene diisocyanate (TDI) derived from polyurethane flexible foam. 

Reg.Toxicol.Pharmacol., 64, (3), Dec., 504-15.

Arnold, R. G., Nelson, J. A., and Verbona, J. J. (1957). Recent advances in isocyanate chemistry. 

Chem.Rev., 57, 47-76.

Brochhagen, F. K. and Grieveson, B. M. (1984). Environmental aspects of isocyanates in water 

and soil. Cell.Pol., 3, 11-17.

Conte, A. and Cossi, G. (1981). Gas chromatographic determination of free TDI in flexible 

urethane foams. J.Chrom., 213, 162–5.

Center for the Polyurethanes Industry, American Chemistry Council (2013). 2012 End-Use 

Market Survey on the Polyurethanes Industry. 

Dieterich, D., Grigat, E., Hahn, W., Hespe, H., and Schmelzer, H. G. (1993). Pinciples of 

polyurethane chemistry and special applications. In:„Polyurethane handbook: 

Chemistry - raw materials - processing - application - properties‟, 2nd.ed., Ed G. Oertel, 

Carl Hanser Verlag, Munich. (ISBN 3-446-17198-3). Ch.2. pp. 11-53.

Elwell, M. J., Mortimer, S., and Ryan, A. J. (1994). A synchrotron SAXS sudy of structure 

development kinetics during the reactive processing of flexible polyurethane foam. 

Macromolecules, 27, (19), 5428-39.

Gagné, S., Lesage , J., Ostiguy, C., and Van Tra, H. (2003). Determination of unreacted 2,4-

toluene diisocyanate (2,4TDI) and 2,6-toluene diisocyanate (2,6TDI) in foams at ultratrace 

level by using HPLC-CIS-MS-MS. Analyst, 128, (12), Dec., 1447-51.
Page 14 of 15

Hager, S. L., Craig, T. A., Jorgenson, M. W., Artavia, L.D., and Macosko, C. W. (1994). 

Interfacial mixing of urethane foam chemicals. J.Cell.Plast., 30, (1), 44-58.

Hauptmann, G., Dörner, K-H., Hocker, J., Illger, H. W., and Pfisterer, G. (1981). Chemische und 

physikalische Vorgänge bei der Herstellung von Polyurethan-Weichschaumstoffen. 

Angew.Makromol.Chem., 98, (1), 237-53.

Hugo, J. M., Spence, M. W., and Lickly, T. D. (2000). The determination of the ability of 

polyurethane foam to release toluene diisocyanate into air. Appl.Occup.Environ.Hyg., 15, 

(6), 512-9.

Jedrzejczak, K. and Gaind, V. S. (1993) Determination of free toluene diisocyanates in flexible 

polyurethane foams using negative chemical-ionization mass spectroscopy. Analyst, 118, 

149–52.

Joel, D., Weiler, M., and Wagner. K. (1982). Biurethstrukturen in PolyurethanWeichschaumstoffen. Plaste Kautsch., 29, (1), 22-6.

Joel, D. and Weiler, M. (1980) Zur Bestimmung von aromatisch substituierten Allophanatund/oder Biuretgruppen in NCO-haltigen Polyurethanvorprodukten. Plaste Kautsch., 27, 

(7), 374-6.

Kelly, T. J., Myers, J. D., and Holdren, M. W. (1999). Testing of household products and 

materials for emission of toluene diisocyanate. Indoor Air, 9, (2), 117-24. 

Krone, C. A., Ely, J. T. A., Klingner, T., and Rando, R. J. (2003). Isocyanates in flexible 

polyurethane foams. Bull.Environ.Contam.Toxicol., 70, 328-35. 

Lapprand, A., Boisson, F., Delolme, F., Méchin, F., and Pascault, J-P (2005). Reactivity of 

isocyanates with urethanes: conditions for allophanate formation. Polym.Degrad.Stab., 90, 

363-73.

McClusky, J. V., Priester, R. D., O'Neill, R. E., Willkomm, W. R., Heaney, M. D., and Capel, M. 

A. (1994). The use of FT-IR and dynamic SAXS to provide an improved understanding of 

the matrix formation and viscosity build of flexible polyurethane foams. J.Cell.Plast., 30, 

(4), 338-60.

Prueitt, R. L., Rhomberg, L. R., and Goodman, J. E. (2013). Hypothesis-based weight-ofevidence evaluation of the human carcinogenicity of toluene diisocyanate. 

Crit.Rev.Toxicol., 43, (5), May, 391-435. 

Saunders, J. H. and Hardy, E. E. (1953). The reaction of tolylene diisocyanate dimer with 

dibutylamine. J.Am.Chem.Soc., 75, (21), 5439-40.
Page 15 of 15

Schmidtkunz, C. (2012). Role of derivatising agents in cleavage reactions with polyurethane 

matrices. III Report No. 11633. International Isocyanate Institute, Manchester, UK.

Spence, M. (2012) TDI-based PU foam: risk assessment tool. SO Report 2012/G. III Scientific 

Office, Manchester, UK.

Van Gheluwe, P., Cole, K. C., Hébrard, M. J., and Leroux, J. (1987). Attenuated total reflectance 

infrared spectroscopic analysis of high index foams. J.Cell.Plast., 23, Jan., 73-85.

Vangronsveld, E., Berckmans, S., and Spence, M. (2013a). Toluene diisocyanate emission to air 

and migration to a surface from a flexible polyurethane foam. Ann.Occup.Hyg., 57, (5), 

650-61.

Vangronsveld, E., Berckmans, S., and Spence, M. (2013b). Comparison of solvent/derivatization 

agent systems for determination of extractable toluene diisocyanate from flexible 

polyurethane foam. Ann.Occup.Hyg., 57, (5): 640-9.

Yakabe, Y., Henderson, K. M., Thompson, W. C., Pemberton, D., Tury, B., and Bailey, R. E. 

(1999). Fate of methylenediphenyl diisocyanate and toluene diisocyanate in the aquatic 

environment. Environ.Sci.Technol., 33, (15), 2579-83.

US FDA (2007) Guidance for Industry. Preparation of premarket submissions for food contact 

substances: chemistry recommendations. U.S. Department of Health and Human Services, 

Food and Drug Administration, Center for Food Safety and Applied Nutrition , College 

Park, MD. Available from < 

http://www.fda.gov/Food/GuidanceRegulation/GuidanceDocumentsRegulatoryInformation

/IngredientsAdditivesGRASPackaging/ucm081818.htm#iid1c > [Accessed 11 Nov., 2013].