Environmental and Health Assesment of Alternatives to Phthalates and to
flexible PVC

4.Use patterns and substitutes  

4.1 Use patterns of phthalates
4.1.1 Assessment of use of phthalate plasticisers
4.2 Selection of substitute substances
4.2.1 Assessed substitutes for phthalates - substances
4.2.2 Assessed substitutes for flexible PVC - materials
4.3 Proposed use pattern for substitutes
4.3.1 Substitution matrix for the 11 substances in tons
4.3.2 Substitution matrix for the two materials
4.4 Assessment of emission and exposure
4.4.1Considerations regarding specific uses of phthalates/substitutes
4.4.2 Worker and consumer exposure
4.4.3 Exposure in environment
4.4.4 Migration potential

4.1 Use patterns of phthalates

4.1.1 Assessment of use of phthalate plasticisers

Many polymer products need to be flexible and soft so they can take on a different shape and form depending on their application. This plastification is often conducted using plasticisers such as phthalates, adipates, trimelli-tates and citrates.

The major uses of flexible PVC in Western Europe is in the product groups of film and sheet, wire and cable, floor covering, extrusions, coated fabrics and plastisols (European Council for Plasticisers and Intermediates, 2000).

PVC plasticisers
According to the European Council for Plasticisers and Intermediates there are more than 300 different types of plasticisers of which about 50-100 are in commercial use (European Council for Plasticisers and Intermediates, 2000). The most commonly used plasticisers are phthalates.

In the Danish Product Register, close to 180 different plasticisers are registered in a wide range of products.

According to the European industry 95% of the plasticiser production is for PVC end-use. In Denmark phthalate in PVC contributes with 90% of the turnover of phthalates (Hoffmann, 1996).

Plasticisers are used in a wide range of products from toys, babycare items, medical devices, wall-coverings, electrical cables, automotive parts, pack-aging, coatings and in the manufacture of clothing and footwear.

Smaller quantities of plasticisers are also used in paints, rubber products, adhesives and some cosmetics. A small amount is used as denaturant in cosmetics such as "sun-tan oil".

In Denmark, phthalates are used as plasticisers in various PVC-products for medical utilities, packaging, cables, fittings, floor/wall covering, but there is still a an extensive, not specified, consumption of phthalates in plasticised PVC products (Hoffmann, 1996). This "Other application of PVC" covers e.g. the use of phthalates in plastisol (coating materials) and toys. Artificial leaders are e.g. produced by coating textile with plastisol. The plastisol con-sists of a PVC-resin, solvent and a plasticiser e.g. phthalates.

In Denmark, phthalates are used as plasticisers in non-PVC materials such as lacquer, paint, printing inks, adhesives, fillers and denaturants in cosmet-ics. The unspecified consumption of phthalates in non-PVC applications is small compared to the use in PVC (Hoffmann, 1996). Capacitors with di-electric fluid may contain phthalates (notably DEHP), but in Denmark most capacitors are dry and therefore without fluids. Another use of phthalates in non-PVC products is in ceramics for electronic products. It is assumed that the used amounts associated with these applications are relatively small in Denmark.

The use of phthalates as plasticisers a.o. in 1992 in Denmark was assessed in the Substance Flow Analysis (Hoffmann, 1996). This analysis indicates that the Danish distribution of the applications of phthalates in 1992 can be illustrated as in Figure 4.1.

Illustration. The distribution of phthalates for applications in Denmark in 1992 (Hoff-mann, 1996) (5 Kb)

Figure 4.1 The distribution of phthalates for applications in Denmark in 1992 (Hoffmann, 1996).

As mentioned earlier, the use of phthalates in PVC-toys is included in "other applications of PVC". This amount is assumed equal to the use of DEHP for flexible PVC-toys. This includes phthalates used for toys for children both less and more that 3 years old ~ 380 ton/year. The use of phthalates are now banned for the former category.

It appears that the amount of phthalates within certain applications is de-creasing. This trend is illustrated in Table 4.1, where the development in the use pattern is listed.

Table 4.1 Development in the use pattern of phthalates in different applications in Denmark.

Application Subapplication Amount phthalate in 1992 in tonnesa

Amount phthalate in 1994 in tonnesb

Est. amount of phthalate in 2000 in tonnesc Trend

PVC

Medical utilities

240-350

240

 

increasing a

Packaging

200-350

100

 

decreasing a

Construction and installations:

- cables

- fittings

- floor and wall covering

 

 

     

3,000

3,500

 

constant a

80

700

 

constant a

1,500

2,000

 

increasing a

other application

4190

3,100

 

e

Subtotal

9,200-9,500

9,640

 

d

Non-PVC

Lacquer and paint

45-225

189g

70

decreasing
a and c

 

Printing ink

90-270

 

50

decreasing
a and c

 

Adhesives

160-220

350g

220

constant c

 

Fillers

< 400

 

100

decreasing c

 

Denaturants

< 5

   

? a

 

Other non-PVC applications e.g. in rubber, concrete and silicone

< 50f

   

? a

Total

 

9,500-10,700

11,000

   

aHoffmann (1996)
b
The Danish Plastics Federation (1996)
c
Hansen and Havelund (2000)
d
At the moment increasing globally and constant on the Nordic market, but decreasing a little on the Danish marked.
e
According to SFA (Hoffmann, 1996) consumption is decreasing but according to the Danish Plastics Federation (1996) it might be increasing.
f
The application "other applications" under non-PVC -products in Hoffmann (1996) is estimated to cover as a maximum 50 tons.
g
Inventory for the Consumption in 1994 made by FDLF for The Danish EPA.

The trend shown in Table 4.1 for the non-PVC-products, is a decline in the consumption of phthalates. Concerning the PVC-products the general trend is difficult to deduce from Table 4.1. According to the suppliers the overall consumption is at the moment increasing but within the near future it is ex-pected to decline.

The consumption of phthalates is slightly increasing in the EU as a whole, stagnant in northern Europe, and decreasing slowly in Denmark (Hansen and Havelund, 2000).

4.2 Selection of substitute substances

In the following the background for the selection of the 11 substitutes for phthalates is described. In Table 4.2 a total of 18 compounds are listed that, in variable degree, all are potential substitutes for phthalates.

  • 5 chemical compounds (substitutes), and
  • 6 groups of substances.

Within each of the 6 groups, one specific substance has been selected as marker for the group.

The primary source of information is the industry and the initial information from The Danish Product Register.

To get an impression of how the substitution will take place selected indus-trial organisations have been contacted. Suppliers and users of phthalates and/or have been contacted to give an estimate of how a complete substitu-tion of phthalates 5 years from here can be predicted.

The same substance will not substitute phthalates in all applications. The substitution will within the different applications take place by a distribution of substitutes. Estimates of this distribution are given in the substitution matrix in Table 4.5 and Table 4.6.

In Table 4.2, a short description of the selection of substitutes for phthalates for various applications is given.

Table 4.2 The plasticiser substitutes and suggestions for example substances in the groups of plasticisers. Other possible substitutes are shown in italics. 

Group of
plasticiser

Name of substance

CAS No.

Adipate

Diethylhexyl adipate

103-23-1

Diisodecyl adipate

27178-16-1

Diisooctyl adipate

1330-86-5

Citrate

O-acetyltributyl citrate

77-90-7

Phosphate

Di(2-ethylhexyl) phosphate

298-07-7

Tri(2-ethylhexyl) phosphate

78-42-2

Mellitate

Tri-2-ethylhexyl trimellitate

3319-31-1

Alkylsulphonic acid esters

o-Toluene sulfonamide

Toluene ethylsulfonamide

88-19-7

8047-99-2

Butane esters

2,2,4-trimetyl-1,3-pentanediole diisobutyate (TXIB)

6846-50-0

Polyester

No suggestion from industry

-

Epoxyester and epoxydised oils

No suggestion from industry

-

Benzoate

Dipropylene glycol dibenzoate

27138-31-4

Diethylene glycol dibenzoate

120-55-8

Triethylene glycol dibenzoate

120-56-9

Sebacate

Dioctyl sebacate

122-62-3

Dibutyl sebacate

109-43-3

The Danish Product Register has conducted a search on these CAS No.s and a general search to identify which CAS No.s are registered in Denmark as plasticisers.

The result of the general search was that approx. 180 different substances are registered as plasticisers. These were screened with respect to their uses, and only a minority was found to be relevant substitutes for phthalates.

Reduction of the list in Table 4.2 has been performed based on information from the industry, the result of comprehensive information on use patterns from The Danish Product Register, and assessment of the data availability regarding toxicological and ecotoxicological information necessary for the assessment.

4.2.1 Assessed substitutes for phthalates - substances 

The plasticisers assessed are those for which most information is expected to be available for the environmental and health assessment and which have a use pattern involving high PVC volume and/or expected high exposure of humans and/or the environment. The substances are listed in Table 4.3.

Table 4.3 Substances used for the environmental and health assessment.

Chemical group

Name of substance

CAS No.

Suggested by DEPA

Identified in Hansen and Havelund (2000)

Plasticiser according to the PR

Known actual application

Adipates

Diethylhexyl adipate

103-23-1

Compound

+

+

Broad application in PVC and non-PVC

Citrates

O-acetyl tributyl citrate

77-90-7

Compound

+

+

PVC, printing ink and concrete products

Phosphates

Di(2-ethylhexyl) phosphate

298-07-7

Compound

-

-

Broad application in PVC

Tri(2-ethylhexyl) phosphate

78-42-2

Compound

+

+

Paint, glue and adhesive

Mellitates

Tri-2-ethylhexyl trimellitate

3319-31-1

Compound

-

-

Broad application in PVC

Alkylsulphonic acid esters

O-toluene sulfonamide

88-19-7

Group

-

-

Substance proposed by suppliers

Butane esters

2,2,4-trimethyl1,3-pentandioldiisobutyrate (TXIB)

6846-50-0

Group

+

+

Printing ink, paint, glue, adhesive and concrete products.

Polyesters

Polyadipates

-

Group

-

-

Foils, substance proposed by Industry

Epoxy esters and epoxidized oils

Epoxidised soybean oil

8013-07-8

Group

+

+

Printing ink, paint, glue and adhesive

Benzoates

Dipropylene glycol dibenzoate

27138-31-4

Group

+

+

Glue, adhesive

Sebacates

Dioctyl sebacate

122-62-3

Group

+

+

Printing ink and glue

No specific substance to be used as a marker for polyester-substitutes has been identified in PR or from suppliers. The industry has emphasised that these substances may become important and the branch organisation has suggested polyadipate as an example substance. However, no information on health or environmental properties has been identified on this substance or group during the present project.

4.2.2 Assessed substitutes for flexible PVC - materials

Polyethylene (PE) and polyurethane (PU) are both materials which are identified as possible substitutes for flexible PVC in a number of products and they thereby contribute to the overall substitution of phthalates. The two materials polyurethane and polyethylene substitute the PVC polymer as such and not only the plasticiser additive. Both materials are polymers.

The two alternative materials PE and PUR
In this study low density polyethylene (LDPE) rather than high density polyethylene (HDPE) is selected for the environmental and health assess-ment, since it is expected that LDPE will substitute plasticised PVC in the main uses in toys and garden hoses.

PU is expected to substitute plasticised PVC in waterproof cloths, shoes, boots and waders, and PUR based on the diphenylmethane-4,4'-diisocyanate (MDI) monomer is selected for the environmental and health assessment.

LDPE and HDPE
Industrial polyethylenes are thermoplastics, which exist in different ver-sions. Low-density versions (LDPE and Linear LDPE) are produced in branched forms in a structure with long and short branches respectively. LDPE is therefore only partly crystalline and the polymer is highly flexible. Principal uses include packaging film, waste bags and soft type plastic bags, tubes, agricultural mulch, wire and cable insulation, squeeze bottles, house-hold items, and toys. LDPE has already substituted flexible PVC in the majority of household packaging products, and the potential for substitution is therefore greater for other product groups like toys.

High density versions (HDPE) are produced in linear forms which allow the polymer chains to pack closely together. This structure results in a dense and highly crystalline material of high strength and moderate stiffness. Principal uses include bottles, pails, bottle caps, packaging, household appliances, and toys. Because of the strength and stiffness HDPE is more commonly used for industrial products compared to household products and consumers in general are more likely to be exposed to LDPE than HDPE. LDPE and HDPE are assumed comparable with regard to effects on environment and health.

HDPE is used for toys of rigid materials, but the proportion of toys manu-factured from LDPE compared to HDPE is not known. It has been suggested that the two PE polymers have an equal share of toy market, and it is as-sumed that LDPE may lead to higher exposures than HDPE.

Polyurethanes
Polyurethanes cover a broad range of synthetic resinous, fibrous, or elasto-meric compounds belonging to the family of organic polymers made by the reaction of diisocyanates with other difunctional compounds such as glycols (polyols). Polyurethanes are one of the most versatile of any group of plas-tics, capable of an almost infinite number of variations in chemistry, struc-ture and application. Polyurethanes can be produced as a foam, in solid form, as an elastomer, coating, adhesive or binder. Foamed polyurethanes form about 90% by weight of the total market for polyurethanes, but there is also a wide range of solid polyurethanes used in many diverse applications.

By itself, the polymerisation reaction produces a solid polyurethane. Polyu-rethane foams are made by forming gas bubbles in the polymerising mixture, which is achieved by using a blowing agent.

MDI
MDI is one of the most important raw materials to make polyurethane. MDI can be grouped into polymeric MDI, which in the form of foam is being used for several heat protection materials, motor car seats, etc., and mono-meric MDI, being used for shoe soles, coating materials, synthetic leather, etc.

Because of the health risks ascribed to monomeric diisocyanates, much at-tention is paid to the physico-chemical and toxicological properties of the monomer in situations where substitution with a polyurethane is required.

MDI has a particularly low vapour pressure compared to TDI (toluene diiso-cyanate), HDI (hexamethylene diisocyanate) and IPDI (isophorone diiso-cyanate ) and is under European legislation classified as harmful whereas the other mentioned diisocyanates are classified as toxic. This often makes MDI a better choice where it is technologically feasible.

MDI is already used in the production of PU for waterproof clothes, shoes, boots and waders, application areas, which are suggested for substitution of flexible PVC in the substitution matrix, and is therefore selected to the health and environmental assessment.

4.3 Proposed use pattern for substitutes

The Danish Product Register (PR) has been used to establish an overview of the function of phthalates in chemicals until now. The Register mainly con-tains information about chemicals and to a lesser extent about materials.

The historical main use of phthalates in Denmark, summarised in Table 4.1, forms the basis for the search for relevant alternatives in the PR.

The most important function of phthalate has until now been plasticising, but besides this function phthalates had have the function of being denatur-ants in cosmetics (Hoffmann, 1996).

The PR has conducted a search to identify the plasticisers used in selected types of chemical products or materials. The result is illustrated in Table 4.4 for the first 10 that are the substances selected for the assessment. The Poly-ester was not included due to lack of CAS no.

Table 4.4 The registered use of the selected substances as plasticisers in the selected product groups. Data from the Danish Product Register. The polyester plasticiser (polyadipate) was not included due to lack of CAS no. Materials such as cables, profiles, floor and wall covering are not covered by the PR.

CAS No.

Name

Fillers

Paint and lacquers

Adhesives

Printing inks

Plastic in Concrete

Rubber products

PVC packaging

103-23-1

Di(ethylhexyl) adipate

·

·

·

 

·

·

 

77-90-7

O-acetyl tributyl citrate

     

·

·

   

298-07-7

Di(2-ethylhexyl) phosphate

             

78-42-2

Tri(2-ethylhexyl) phosphate

·

·

·

 

·

   

3319-31-1

Tri-2-ethylhexyltrimellitatea

             

88-19-7

Alkylsulfonic acid estera

             

6846-50-0

2,2,4-trimethyl 1,3-pentanediol diisobutyrate (butane ester)

·

·

 

·

·

 

· b

8013-07-8

Epoxidised soybean oil

·

·

·

·

   

·

27138-31-4

Dipropylene glycol dibenzoate

     

·

     

122-62-3

Dioctyl sebacate

   

·

       

a Not found in the Product Register.
b Unclear whether 'plast' is PVC

Not all substances are registered as plasticisers in the selected products. This has to be seen in the light of the fact that the register only contains informa-tion about substances classified dangerous to the environment or the health. The result of the search is therefore as mentioned earlier supplemented with industrial information about the development of plasticisers not containing phthalates.

4.3.1 Substitution matrix for the 11 substances in tons

By using the amounts found within the different applications in the sub-stance flow analyse (Hoffmann, 1996) and the proposed %-distribution of the alternatives in Table 4.5, the following "amount-substitution matrix" shown in Table 4.6 within the different applications can be established.

Table 4.5 Substitution matrix for the 11 substances with anticipated share given in %.

Note: It is only relevant to ad up the figures horizontal and not vertically because each row describe the substitution within one application. One column rep-resents non-comparable figures.

Based on information from the industry, Table 4.6 represents the best pres-ent estimate on substitution of phthalates within different types of products. The dominating amount is for each substance marked in bold. The informa-tion is primarily based on interviews with industry sources rather than trade bodies, since only little overview information is available.

This best present estimate has to be seen in the light of the situation in which all phthalates in a product are substituted by only one substitute.

The actual substitution five years from now, will presumably not be exactly as illustrated in Table 4.6, but the information indicates in which areas the substances might be used extensively and in which areas the use is expected to be negligible.

It should be emphasised that a large portion of the expected use is placed in "Other applications of PVC" (e.g. toys).

Another scenario is that one substance substitutes the phthalates 100% within an application area (a 'worst worst case').

Table 4.6 Substitution matrix for the 11 substances (in tonnes)

Application

Tons phthalates per year (1992)

Diethylhexyl adipate, CAS no. 103-23-1

O-acetyltributylcitrate, CAS no. 77-90-7

Di(2-ethylhexyl)phosphat, CAS no. 298-07-7

Tri(2-ethylhexyl)phosphat, CAS no 78-42-2

Tri-2-ethyl trimellitate, CAS no. 3319-31-1

Toluene sulphonamide, CAS 88-19-7)

2,2,4-trimethyl 1,3-pentanediol diisobutyrate, CAS no. 6846-50-0

Epoxidised soybean oil, CAS no. 8013-07-8

Polyester

Dipropylene glycol dibenzoate, CAS no. 27138-31-4

Dioctyl sebacate, CAS no. 122-62-3

Other substanes and materials

Hospital sector

350

88

53

70

70

   

35

       

35

Packaging

350

53

53

70

35

18

 

53

35

     

35

Cables

3,000

90

 

750

900

840

30

120

30

     

240

Profiles

80

16

 

12

12

8

 

12

     

12

8

Floor and wall covering

1,500

450

 

300

300

150

 

150

       

150

Other application of PVC

4,190

838

251

838

838

838

 

42

       

545

Lacquer and paint

225

23

   

23

   

23

68

     

90

Printing ink

270

54

81

       

27

54

   

54

 

Adhesive

220

22

11

 

22

     

44

33

44

44

 

Filler

400

40

80

 

40

     

20

60

160

   

Other applications e.g. in the following products:

                         

Rubber

50

25

                   

25

Concrete

50

5

25

 

5

   

3

       

13

Silicone

50

                     

50

Sum (max.)

10,735

1,704

554

2,040

2,245

1,854

30

465

251

93

204

110

1,190

 4.3.2 Substitution matrix for the two materials

In view of the general phase out policy for PVC the substitution of phtha-lates may obviously take place exchanging the PVC-material by other mate-rials that do not need to be plastified with phthalates. However, PE and PU cannot substitute flexible PVC across-the-board, but as seen in substitution matrix Table 4.7 PE and PU are possible substitutents for flexible PVC in different kinds of products:

  • PE will mainly substitute flexible PVC in toys
  • PU will mainly substitute flexible PVC in waterproof clothes, shoes, boots and waders.

Using the same procedure as for the 11 substances, but with the 1994-inventory from The Danish Plastics Federation of the consumption of plasti-cised PVC, a substitution matrix for the PVC-substituting materials can be established as in Table 4.8

Table 4.7 Substitution matrix for selected flexible PVC products in % of the total amount plasticised PVC (tonnes).

Application

Tons plasticised PVC

Ethylene-vinyl-acetate (EVA)

EPDM rubber

Polyethylene (PE)

Polypropylene (PP)

Cardboard and paper

Leather

Polyurethane (PUR)

Nylon

Neoprene rubber

Natural rubber

Wood

Other

Sum (100%)

Garden hose

450

60

30

                 

10

100

Office supplies

3,500

     

75

20

5

           

100

Toys

1,130

30

 

30

30

             

10

100

Waterproof clothes

260

           

80

       

20

100

Shoes

200

         

20

50

5

 

20

 

5

100

Boots and waders

380

           

30

 

5

60

 

5

100

Sum

5,920

*

*

*

*

*

*

*

*

*

*

*

*

*

*: The vertical sum across different applications of PVC is not relevant to cal-culate. It is only the horizontal sum within the same application, which is relevant to calculate because it is describing the situation within one spe-cific application and has to add up to 100%.

Table 4.8 Substitution matrix for alternative materials to flexible PVC. The unit is tons.

Application

Tons plasticised PVC

Ethylene-vinyl-acetate (EVA)

EPDM rubber

Polyethylene (PE)

Polypropylene (PP)

Cardboard and paper

Leather

Polyurethane (PUR)

Nylon

Neoprene rubber

Natural rubber

Wood

Other

Sum (100%)

Garden hose

450

270

135

                 

45

450

Office supplies

3,500

     

2,625

700

175

           

3,500

Toys

1,130

339

 

339

339

             

113

1,130

Waterproof clothes

260

           

208

       

52

260

Shoes

200

         

40

100

10

 

40

 

10

200

Boots and waders

380

           

114

 

19

228

 

19

380

Sum

5,920

609

135

339

2,964

700

215

422

10

19

268

 

239

5,920

As for the 11 substances, the information from the industry in Table 4.8 rep-resents the most likely substitution of phthalates within different types of PVC-products. The dominating amount for each material is marked in bold.

Again, the substitution five years from now, will presumably not be exactly as illustrated in Table 4.8, but the information indicates in which areas the materials might be used extensively and in which areas the use is expected to be negligible.

The worst case scenario is when one material substitutes the plasticised PVC 100% within an application area.

As seen in Table 4.8, polyethylene is most likely going to substitute 339 tons flexible PVC in toys. With an average concentration of phthalates in soft-PVC toys, similar to 34%, the 339 tons PVC represent 115 tons phthalates.

Polyurethane is, as shown in Table 4.8, the mayor substitute for PVC in waterproof clothes. It is therefore of special interest to undertake an EUSES-calculation on the 208 tons flexible PVC, which may contain up to 100 tons phthalates.

4.4 Assessment of emission and exposure

Data compilation for substitution matrix
The qualitative information from suppliers of phthalates and the alternative substances is based on an assumed complete substitution of phthalate in the mentioned applications in the near future (a five year perspective).

In Table 4.5 and Table 4.7 the qualitative information is transferred to quantitative figures in percent. These figures form a possible scenario for how the complete substitution can take place. It will probably not corre-spond to the real situation in five years time, but it illustrates where the use of a substance might be extensive and where the use might be negligible. This overview is useful in connection with evaluation of results from calcu-lations in EUSES and in connection with priority of efforts of the environmental regulating authorities.

The 11 substances and the 2 materials in this project are regarded as the main basis for the complete substitution for phthalates.

According to discussion with the organisations listed in the Appendix, the most likely way to substitute phthalates is illustrated in the following sub-stitution matrixes Table 4.5 and Table 4.7.

Substitution matrix for the 11 substances in %
The consumption of phthalates within the relevant applications is based on substance flow analyses covering the situation in 1992 (Hoffmann, 1996). In Table 4.5, the share of 11 substances for the substitution of the phthalates within each application is estimated in %.

According to the Danish Plastics Federation, flexible PVC is not used in packaging, today. The actual consumption of phthalates for this purpose is therefore estimated to be of minor importance.

The first five substances are expected to substitute phthalates directly. The next six are selected as markers for chemical groups from which substitutes are expected to be identified in the near future. Meanwhile the six markers are used to calculate a scenario for substitution of phthalate.

Other substances and materials cover less important substitutions, conducted by other means than the 11 substances. Examples could be substances not covered by the 11 substances in Table 4.6, or new technology in the produc-tion of the mentioned products. The new technology could be the use of new materials without the need for plasticising with phthalates.

The point of origin of Table 4.5 is the Danish consumption of phthalates in 1992 shown in Table 4.1 (Hoffmann, 1996). These data are selected because they are the result of a comprehensive survey, and the studies conducted later, confirm the amounts and the indicated development trends within the different applications. For the non-PVC products a decline in the use of phthalates has been identified (Hansen and Havelund, 2000). For the PVC-products the suppliers expect a decline in the near future.

The background for the ratios in Table 4.5 is information gathered in con-nection with one of the substitution projects initiated by the Danish Envi-ronmental Protection Agency. It is the general impression among suppliers and users of phthalates that a complete substitution will be possible for both PVC and non-PVC products. Available substitutes for non-PVC products have been identified earlier (Hansen and Havelund, 2000).

Table 4.9 Estimated use of the substitutes. These volumes are used for consumer expo-sure

Name of substitute

Expected most relevant application

Expected used amount for the substitution in tons per year

Di(2-ethylhexyl) phosphate, CAS No. 298-07-7

Cables

750

Tri(2-ethylhexyl) phosphate. CAS No. 78-42-2

Cables

900

Tri-2-ethylhexyltrimellitate, CAS No. 3319-31-1

Cables

900

Alkylsulfonic acid ester (toluene sulphonamide, CAS 88-19-7)

Cables

30

Diethylhexyl adipate, CAS No. 103-23-1

Floor and wall covering

450

Butane ester (2,2,4-trimethyl 1,3-pentanedioldiisobutyrate, CAS No 6846-50-0)

Floor and wall covering

150

Epoxidised soybean oil (CAS No. 8013-07-8)

Lacquer and paint

70

o-Acetyl tributyl citrate, CAS No. 77-90-7

Toys

250

Dioctyl sebacate (CAS No. 122-62-3)

Printing ink

50

Polyester

Fillers

60

Dipropylene glycol dibenzoate (CAS No. 27138-31-4

Fillers

160

4.4.1 Considerations regarding specific uses of phthalates/substitutes

Industrial processes
There is no synthesis of phthalates or substitutes for phthalates in Denmark.

The synthesis of phthalates for the Danish market is at the moment mainly conducted in Sweden. The identified substitutes are expected also to be synthesised in countries outside of Denmark.

The main source to emissions and exposures in Denmark is expected to be from formulation of products containing plasticisers such as plasticised PVC, printing inks, adhesives and fillers. For paints and lacquers there is also an emission and exposure from the professional use of the products.

Based on the substitution matrix focus in this investigation has been set on the use of the eleven substances with known potential application the fol-lowing process:

  • Use of di(2-ethylhexyl) phosphate (CAS No. 298-07-7), tri(2-ethylhexyl) phosphate (CAS No. 78-42-2), tri-2-ethylhexyltrimellitate (CAS No. 3319-31-1) and alkylsulfonic acid ester (toluene sulphona-mide, CAS No 88-19-7) in the production of cables

  • Use of butane ester diethylhexyl adipate (CAS No. 103-23-1), (2,2,4-trimethyl 1,3-pentanediol diisobutyrate, CAS No 6846-50-0) in the pro-duction of floor and wall covering

  • Professional use of epoxidised soybean oil (CAS No. 8013-07-8) con-taining lacquer and paint products

  • Use of o-acetyl tributyl citrate (CAS No. 77-90-7) and dioctyl sebacate (CAS No. 122-62-3) in the production of printing inks.

  • Use of polyester and dipropylene glycol dibenzoate (CAS No. 27138-31-4) in the production of fillers.

In general, uses of the products are regarded as diffuse and as minor sources to emission, but concerning consumer exposure of the 10 substances there are relevant scenarios that are described in Section 5.4.

Human exposure is estimated mainly to take place in connection with:

  • Formulation process.
  • Uses of the products

To illustrate the potential human exposure from the 10 well defined sub-stances a calculation in EASE, which is based on the principles in the TDG has been conducted.

EASE calculates a theoretical exposure of humans in the working environ-ment and private consumers.

The input data takes point of origin in the scenarios in Table 4.10, which is assessed to represent the most extensive exposure.

Table 4.10 Exposure scenarios of the 11 substances

Name of substance

Scenarios

Working environment

Consumers

Diethylhexyl adipate
(CAS 103-23-1)

Production of follies to floor and wall coverings

Use of floor and wall coverings in bathrooms

o-acetyltributyl citrate
(CAS 77-90-7)

Production of printed papers

Daily use of printed papers

Di(2-ethylhexyl)phosphate
(CAS 298-07-7)

The well defined step in the production of cables which is the exposure just after the extrusion of cables and before the cooling in water

Contact with cables in a private house

Tri(2-ethyl)phosphate
(CAS 78-42-2)

The well defined step in the production of cables which is the exposure just after the extrusion of cables and before the cooling in water

Contact with cables in a private house

Tri-2-ethylhexyltrimellitate
(CAS 3319-31-1)

The well defined step in the production of cables which is the exposure just after the extrusion of cables and before the cooling in water

Contact with cables in a private house

o-Toluene sulphonamide
(CAS 88-19-7)

The well defined step in the production of cables which is the exposure just after the extrusion of cables and before the cooling in water

Contact with cables in a private house

2,2,4-trimethyl 1,3-pentanediol diisobutyrate (CAS 6846-50-0)

Production of follies to floor and wall coverings

Use of floor and wall coverings in bathrooms

Epoxidised soybean oil
(CAS 8016-11-3)

Professional painting in a room without ventilation

Stay in a painted house and conducting painting once a year

Polyester

Production of fillers

Stay in a bathroom with fillers

Dipropylene glycol dibenzoate
(CAS 27138-31-4)

Production of fillers

Stay in a bathroom with fillers

Dioctyl Sebacate
(CAS 122-62-3)

Production of printing inks

Half an hour interior reading in printed papers

To approach a situation five years from now the exposure calculation in EUSES is therefore conducted for both the most likely situation represented in bold figures and the 100%-scenario.

4.4.2 Worker and consumer exposure

Assessment of the exposure of humans in the working environment and con-sumers has been conducted using the model Estimation and Assessment of Substances Exposure Physico-chemical Properties (EASE), which is a part of the model European Union System for the Evaluation of Substances (EUSES).

Limitations and uncertainties of the EASE
The equations in EASE are intended to provide a simple description of con-sumer exposure. Most equations give a worst case estimation of exposure, by assuming that all of the compound in the product is at once available for intake and uptake. Intake and uptake themselves are modelled as simple fractions.

Workers exposure
EASE provides a general-purpose predictive model for exposure assessment in the workplace. The model predicts external exposure only: it does not take into account absorption and bioavailability.

If reliable and representative measured data are available these can be used to overwrite the model results. The general-purpose model is called EASE (Estimation and Assessment of Substance Exposure) which is described in details in Section 2.2 of the TGD.

EASE was specifically developed for the purpose of modelling inhalation and dermal workplace exposure across a wide range of circumstances.

EASE is an analogue model, i.e. it is based on measured data which are as-signed to specific scenarios. The user can build scenarios by choosing be-tween several options for each of the following variables: physical proper-ties during processing (tendency to become airborne, potential for dermal contact), use pattern and pattern of control. Numerical ranges have been as-signed using measured data contained within the UK National Exposure Database for inhalation exposure, and experimental data and expert judge-ment for dermal exposure.

The data used to assign ranges within the model are all 8-hour time weighted averages and the numbers generated by the model are only valid when the exposures being assessed can be related to such averages.

The output of EASE is numerical ranges of concentrations or ppm. These are converted from ppm to kg.m-3 and can be used as input for risk charac-terisation in which the exposure estimates are compared to the results of the human effects assessment.

Consumer-exposure
The consumer, i.e. a member of the general public who may be of any age, either sex, and in any stage of health may be exposed to chemical substances by using consumer products.

A consumer product is one, which can be purchased from retail outlets by members of the general public and may be the substance itself, or a prepara-tion, or an article containing the substance.

The EASE equations for consumer exposure can be used to estimate exter-nal exposure substances used as or in consumer products. Absorption or bioavailability is not taken into account by the equations implemented in EASE.

The focus in EASE is on substances used indoors for a relatively short pe-riod of time per event (such as e.g. a carrier/solvent in a cosmetic formula-tion; a powder detergent).

The equations in the model apply to both volatile substances and airborne particulates. It is assumed the substance is released as a vapour, gas, or air-borne particulates, and the room is filled immediately and homogeneously with the substance. Ventilation of the room is assumed to be absent.

The equations can also be adapted to estimate exposure arising from 'rea-sonably foreseeable misuse', i.e. when products are not used according to the instructions, but as if they were other, allied products.

To adapt the equations, the values for the parameters used in the equations are changed to reflect values foreseen in "reasonably foreseeable misuse". For example, the volume of product or the area of application is set to a dif-ferent value, reflecting reasonable foreseeable misuse.

If a substance is released relatively slowly from a solid or liquid matrix (e.g. solvent in paint, plasticiser or monomer in a polymer, fragrance in furniture polish), the equation in EASE acts as a worst case estimation, estimating the maximum possible concentration.

Dermal
The calculation in EASE has in this investigation been operating with two scenarios concerning dermal exposure: A and B

Dermal A: a substance contained in a medium. This dermal scenario also applies to

  • a non-volatile substance in a medium used without further dilution (set dilution D=1), and
  • a non-volatile substance in a volatile medium.

The assumption behind the equations in the calculations is that all of the substance on the skin is potentially available for uptake. This is the case when the medium is well mixed or only present as a thin film on the skin. The dermal equations apply for:

  • a non-volatile substance in a diluted product, 
  • a non-volatile substance in a medium used without further dilution, and,
  • a non-volatile substance in a volatile medium.

Dermal B: a non-volatile substance migrating from an article (e.g. dyed clothing, residual fabric conditioner, dyestuff/newsprint from paper).

The assumption behind the equation is that only part of the substance will migrate from the article (e.g. dyed clothing, residual fabric conditioner, dye-stuff/newsprint from paper) and contact the skin. The migration is assumed to be slow enough to be represented by a constant migration rate multiplied by the time of contact.

The exposure calculation will involve estimating the amount of substance which will migrate from the area of the article in contact with skin during the time of contact. Dyestuff amounts in fabrics and paper are usually given as weight of product per unit area (e.g. mg/m2).

Oral
The calculation concerning oral exposure has also been operating with two scenarios: A and B.

Oral A: a substance in a product unintentionally swallowed during normal use (e.g. toothpaste).

The exposure equations may also be used to estimate exposures arising from ingestion of the non-respirable fraction of inhaled airborne particulates.

The equations may also be used to estimate exposures arising from ingestion of the non-respirable fraction of inhaled airborne particulates.

Oral B: a substance migrating from an article into food or drink (e.g. plastic film, plastic-coated cups/plates).

It is assumed that the substance in a layer of thickness of article (e.g. plastic film, plasticcoated cups/plates) in contact with the food will migrate to the food. The migration rate is assumed to be constant, and the migration rate multiplied by the contact duration is the fraction of substance that is migrated to the food. The equation can be used to give a conservative estimate of substance uptake by a defined volume of food. The value of the migration rate will be influenced by the type of food (e.g. fatty/dry/moist), the period of exposure and the temperature at which it occurs. Consumer exposure level will also be influenced by the proportion of contaminated food eaten.

Use pattern scenarios
Based contacts to the Danish industry and the substance flow analyse (Hoffmann, 1996) relevant scenarios has been identified and are described in section 4.3.

The background for choosing scenarios is the most likely way of substitu-tion described by industrial actors and rendered in the substitution matrix in Table 4.5. Within the substitution matrix the application representing the largest estimated consumption of each substitute is selected as the most relevant scenario. This application is marked in bold figures in the substitu-tion matrix.

The input data for the calculation are the substitution matrix and scenarios with the largest estimated consumption substitute for phthalate plasticisers.

With point of origin in the substitution matrix the substances are distributed in the following most relevant application areas.

Plasticisers in the "Cables"-application are expected to be:

  • Di(2-ethylhexyl) phosphate, CAS No. 298-07-7
  • Tri(2-ethylhexyl) phosphate. CAS No. 78-42-2
  • Tri-2-ethylhexyltrimellitate, CAS No. 3319-31-1
  • Alkylsulfonic acid ester (o-toluene sulphonamide, CAS No 88-19-7).

For the production of "floor and wall covering" the following plasticisers are chosen:

  • Diethylhexyl adipate, CAS No. 103-23-1
  • Butane ester (2,2,4-trimethyl 1,3-pentanediol diisobutyrate, CAS No 6846-50-0).

Concerning the production of lacquer and paint the focus is on:

  • Epoxidised soybean oil (CAS No. 8013-07-8).

In connection with printing ink the relevant substances are estimated as:

  • O-acetyl tributyl citrate, CAS No. 77-90-7
  • Dioctyl sebacate (CAS No. 122-62-3).

The production of "fillers" is assumed to include:

  • Polyester
  • Dipropylene glycol dibenzoate (CAS No. 27138-31-4).

The scenarios in EASE for the consumer exposure are based on the amounts for these uses and the exposure characteristics for the application.

4.4.3 Exposure in environment

Substance parameters
For each substance the required input parameters molecular weight, octanol-water partition coefficient, water solubility, vapour pressure and physical state were fed to the model in accordance with the data search and evaluation.

Two types of assessments were performed for each substance substituting phthalates. One scenario simulates the best educated guess for the future share that this particular substance would gain in the market based on inter-views with the industry. The second assessment simulates the hypothetical situation where only one of the alternatives (100% substitution case) sub-stitutes the entire tonnage of phthalates.

In the 100% substitution case it is chosen to base the estimates on the most recent inventory of the phthalates in PVC and use the sum used in 1992 (10,735 tons). In various applications substitutes may be used in different volumes than the phthalates - if 1 kg new substance can substitute 2 kg phthalate or vice versa. Since the available information on this is very in-complete it has been decided not to try to include such information in the calculations.

The physical parameters of some of the compounds are out of the advised range in which EUSES operates. In the cases where the physical parameters are out of the pre-set range (e.g. logPow > 6) or unknown as melting and boiling point sometimes are, it has been chosen to use the nearest maximum or minimum value as suggested in EU TDG or use a worst case approach.

All results are presented in the report with two significant digits rounded off from the EUSES calculations with three significant digits (given in appen-dix).

The assessment of emission to the environment and exposure of man and biota from environmental concentrations of phthalate alternatives are based on the procedures outlined in the EU TGD (EU Commission 1996). The actual concentrations are calculated by using the PC program EUSES (European Chemicals Bureau 1996), which is designed to provide decision support for the evaluation of the risks of substances to man and the envi-ronment based directly on the EU TGD.

In the present evaluation EUSES is operated in three of the possible five modes. Parameters are entered for: 

  1. Environmental assessment,
  2. Predators exposed via the environment and
  3. Humans exposed via the environment.

EUSES will calculate concentrations and doses for the assessment on three spatial scales: the local (point source), the regional (small and densely in-habited country) and the continental (Europe). The default regional scale has been changed to suit Danish conditions (see below). The local and conti-nental scenarios are included in the calculations, but no specific values have been entered.

The EUSES program calculates environmental exposure based on 1) a physical scale where the use and emission takes place, 2) the use and emis-sion pattern of the substance and 3) on substance specific parameters. The specific parameters for each substance are provided for each exposure esti-mation. To assist the comparison between substances the physical dimen-sions of the scenario and the overall industrial use and emission pattern has been set identical for all substances.

Use and emission scenarios
The use and emission scenarios rely on the database of emission scenario documents for a number of industrial uses included in EUSES. The follow-ing settings have been used to represent the primary use of phthalate alter-natives:

Emission input data

No.

Name

Industry category

11

Polymers industry

Use category

47

Softeners

Main category (production)

III

Multi-purpose equipment

Main category (formulation)

III

Multi-purpose equipment

Main category (processing)

IV

Wide dispersive use

Danish regional scenario
The physical dimensions of the regional scenario have been set at values representative for Denmark, those changed are shown in Table 4.11 (a com-plete list of parameters can be found in the Appendix). The values were taken from the evaluation of the SimpleBox Model for Danish conditions (Miljostyrelsen 1995).

Table 4.11 Parameters of the EUSES model, which were adapted to Danish conditions

Parameter Value Units
Fraction of EU production volume for region 0.05 [-]
Fraction connected to sewer systems 0.9 [-]
Environmental temperature 7.7 [oC]
Volume fraction water in soil 0.4 [m3.m-3]
Weight fraction of organic carbon in soil 0.025 [kg.kg-1]
Number of inhabitants of region 5.30E+06 [eq]
Wind speed in the system 5 [m.s-1]
Area of regional system 4.30E+04 [km2]
Area fraction of water of the regional system 0.011 [-]
Area fraction of natural soil 0.332 [-]
Area fraction of agricultural soil 0.647 [-]
Area fraction of industrial/urban soil 0.01 [-]
Suspended solids concentration of regional system 17.7 [mg.l-1]
Net sedimentation rate 8.22 [mm.yr-1]
Average annual precipitation

735

[mm.yr-1]
Fraction of rain water infiltrating soil 0.46 [-]
Calculate dilution from river flow rate No
Mixing depth of grassland soil 0.05 [m]
Mixing depth agricultural soil 0.2 [m]

4.4.4 Migration potential

A key parameter in comparing various plasticisers is their potential for mi-grating out of the PVC polymer. Only few data has been identified on mi-gration potential for the substitutes. The information on migration potential will be used in the expert assessment process, but is not used in the exposure calculation model.

To determine the total migration potential various reference methods are used which all are available as CEN standards (ENV 1186-1 - ENV 1186-12). Several new standards in this area are in preparation.

In general the methods are divided in two categories: Migration from plastic to an oily extractant and migration from plastic to an aqueous solution.

To determine the total migration potential using the two groups of methods either a double sided test (total submergence of plastic piece) or a single sided test (using a migration cell or by incorporating the plastic piece into a bag) is performed.

The total migration potential is determined as the difference in weight be-fore and after extraction or as weight of the evaporation residue of the ex-tractant.

The 3 commonly water based extractants are distilled water, 3% acetic acid and 10 % ethanol. Since most plasticisers are lipophilic it is most relevant to express the migration as migration from plastic to fat containing food. As fat simulator olive oil is the commonly used.

The amount of plasticiser extracted is extractant dependent and usually the extraction time of olive oil and 95% ethanol is 10 days at 40 °C and for iso-octane 2 days at 20 °C.

The difference in extraction time is due the extraction power of each ex-tractant and the ability of the extractant to make the plastic swell. When the plastic swells the dept of the layer in contact with the extractant increases and the amount of platisicer extracted increases.

The extraction power of the extractant types depends on the plastic type that is investigated, but usually, when considering plastics that contains lipo-philic plasticisers the order extraction power is: isooctane > olive oil > etha-nol..


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