Bis(2-ethylhexyl) phthalate

Additional information on environmental fate and behaviour

Administrative data

Endpoint:

additional information on environmental fate and behaviour

Type of information:

other: review article

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: 2g: Data from handbook or collection of data. Reliablity and realistic data and environmental conditions were taken into consideration by authors

Data source

Reference

Reference Type:

review article or handbook

Title:

Degardation of phthalate esters in the environment.

Author:

Peterson D.R. and Staples C.A.

Year:

2003

Bibliographic source:

in "The handbook of environmental chemistry", Vol 3, Part Q, 85-124.

Materials and methods

Test guideline

Qualifier:

no guideline required

Principles of method if other than guideline:

This study is an analysis of the published data regarding fate an behaviour of organic contaminants (including DEHP) in the different compartment of the environment.

Type of study / information:

General analysis of the fate and behaviour of DEHP in all environment compartments.

Test material

Test material information

Constituent 1

Reference substance name:

bis(2-ethylexyl) phthalate

IUPAC Name:

bis(2-ethylexyl) phthalate

Constituent 2

Reference substance name:

Bis(2-ethylhexyl) phthalate

EC Number:

204-211-0

EC Name:

Bis(2-ethylhexyl) phthalate

Cas Number:

117-81-7

Molecular formula:

C24H38O4

IUPAC Name:

1,2-bis(2-ethylhexyl) benzene-1,2-dicarboxylate

Results and discussion

Any other information on results incl. tables

The half lifes defined for high molecular weight phthalic acid esters by the authors are summarized in the following table:

Environmental compartment	Route	Rate (d-1)	Half-life (d)	Half life (h)
Surface water and sediment	Biodegradation (aerobic)	0.2-2.0	3.5-0.35	84-8.4
Soil	Biodegradation (aerobic)	0.01-0.1	69-7	1663-166
Soil and sediments	Biodegradation (anaerobic)	0.006-0.1	116-69	2784-1656
Wastewater	Slurry phase	0.75	0.92	22
Air	Photolysis (indirect)	3.5-1.2	0.6-0.3	14.4-7.2

 

The results are clearly in opposition with conclusion of the RAR (2008). However and as described by the authors, the guidance document R16 on Environmental exposure estimation specified increase in half lives with an increase in Kp is based o the hypothesis that chemicals adsorbed on sediment are not degraded. The authors based their estimation on environmentally relevant studies on natural water, inoculates from likely to be impacted by phthalates esters.

 

Moreover, since this analysis, new studies have demonstrated that DEHP is degraded in soil and sludge from WTP even after adsorption. These data support the analysis made by Peterson and Staples (2003).

Applicant's summary and conclusion

Conclusions:

In the analysis made by the authors, and according to guidance document R11 on PBT assessment, DEHP does not fulfill the criteria for persistence as none of the half lives is equal or above the thresholds of 60 days in marine water, 40 days in freshwaters, 180 days in marine sediment or 120 days in freshwater sediments and soil.

Executive summary:

Peterson and Staples examined measured and modelised data on phthalic acid esters in order to estimate the fate in every environment compartments. The authors selected relevant and reliable data from the literature available in 2003 on of phthalic acid esters. They gave priority to simulation studies, microcosms and field studies done under environmentally realistic conditions. They perform their analysis for each compartment and took in consideration abiotic and biotic factors (in particular the bioavailability, the concentration of the substance, oxygen conditions).

On basis of their properties (Kp, LogKow, volatilization) authors considered separately low and high molecular weight substances between C1 to C4 alcohol side chain and C6 and above alcohol side chain respectively. DEHP is in the second category.

The half lifes defined for high molecular weight phthalic acid esters by the authors are summarized in the following table:

Environmental compartment	Route	Rate (d-1)	Half-life (d)	Half life (h)
Surface water and sediment	Biodegradation (aerobic)	0.2-2.0	3.5-0.35	84-8.4
Soil	Biodegradation (aerobic)	0.01-0.1	69-7	1663-166
Soil and sediments	Biodegradation (anaerobic)	0.006-0.1	116-69	2784-1656
Wastewater	Slurry phase	0.75	0.92	22
Air	Photolysis (indirect)	3.5-1.2	0.6-0.3	14.4-7.2

 

In the analysis made by the authors, and according to guidance document R11 on PBT assessment, DEHP does not fulfill the criteria for persistence as none of the half lives is equal or above the thresholds of 60 days in marine water, 40 days in freshwaters, 180 days in marine sediment or 120 days in freshwater sediments and soil.

The results are clearly in opposition with conclusion of the RAR (2008). However and as described by the authors, the guidance document R16 on Environmental exposure estimation specified increase in half lives with an increase in Kp is based o the hypothesis that chemicals adsorbed on sediment are not degraded. The authors based their estimation on environmentally relevant studies on natural water, inoculates from likely to be impacted by phthalates esters.

 

Moreover, since this analysis, new studies have demonstrated that DEHP is degraded in soil and sludge from WWTP even after adsorption. These data support the analysis made by Peterson and Staples (2003).