2,2'-[(1-methylethylidene)bis(4,1-phenyleneoxymethylene)]bisoxirane

PBT assessment

PBT assessment: overall result

PBT status:

the substance is not PBT / vPvB

Justification:

The data show that the properties of the substance do not meet all the specific criteria detailed in Annex XIII or do not allow a direct comparison with all the criteria in Annex XIII but nevertheless indicate that the substance would not have all these properties and the substance is not considered a PBT/vPvB.

Table1: Summary conclusion on PBT or vPvB properties

Constituent	P/vP	B/vB	T
Structure A, n=0	t½, hydrolysis= 5 d (25°C)^(1)	log Pow=3.24^(2) BCFQSAR= 31^(3)	NOEC21 d.D.magna                        = 0.3 mg/l^(4) NOEC72 hr.S.capricornutum                        = 2.4 mg/l^(5) Neither classified as carcinogen, nor as mutagen, repro toxicant, T-R48, nor Xn-R48.
	t½,< 40 d Not P based on REACH Annex XIII.	BCFQSAR< 2000 Not B based on screening criteria.	NOECaquatic, chronic                >0.01 mg/l No relevant classification Not T based on REACH Annex XIII
Structure A, n=1	t½, hydrolysis: not determined. Likely to be the same or very similar to Structure A, n=0	log Pow=7.25^(6)BCFQSAR= 13^(3)	Not available.
	t½,likely< 40 d Not P based on screening criteria.	BCFQSAR< 2000 Not B based on screening criteria.	Not assessed
Structure B	t½, hydrolysis: not determined. Likely to be the same or very similar to Structure A, n=0	log Pow / BCF not determined likely to be similar to structure A, n=0	Not available.
	t½,likely< 40 d Not P based on screening criteria.	BCFQSAR< 2000 Not B based on screening criteria.	Not assessed
Hydrolysis product (this is the di-diol, not the monodiol Structure C)	Not readily biodegradable	BCFQSAR= 3^(3)	Not available.
	P based on screening criteria.	BCFQSAR< 2000 Not B based on screening criteria.	Not assessed

⁽¹⁾P.R. Fisk (1993);⁽²⁾Section 1.3;⁽³⁾The Dow Chemical Company (2010b);⁽⁴⁾Shell Sittingbourne Research Centre (1984);⁽⁵⁾Cheesman, H., Girling, A.E. (1991);⁽⁶⁾EPISuite.

PBT/vPvB criteria and justification

Relevant constituents:4,4'-Isopropylidenediphenol, oligomeric reaction products with 1-chloro-2,3-epoxypropane ("BADGE") is a mono constituent substance. It consists of the main component with see (Structure A, n=0 inTable2), and with decreasing prevalence: n=1 (12%) and n=2 (1.3%) and as impurities the epoxydised ortho-Bisphenol A (Structure B, approx. 1%), the diol formed from hydrolysis of the epoxy group (Structure C, approx. 1%), and other unspecified impurities with each less than 1%.

Table2: Relevant constituents in 4,4'-Isopropylidenediphenol, oligomeric reaction products with 1-chloro-2,3-epoxypropane (CAS:25068-38-6)

	CAS#	Typical wt%	Structure
Structure A, n=0	1675-54-3	85
Structure A, n=1	25068-38-6	12
Structure A, n=2	25068-38-6	1.3
Structure A, n=3	25068-38-6	<1
Structure A, n>3	25068-38-6	<1
Structure B		1	CC(C)(c2ccccc2OCC1CO1)c4ccc(OCC3CO3)cc4
Structure C		1
Unidentified impurities, each below 5%		0.7

 

No relevant monitoring data has been identified to be considered in the PBT assessment.

Persistence assessment: No data is available on elimination half-life of the main constituent from simulation testing in water, sediment, or soil. The main constituent is not persistent based on the hydrolysis half-life of 117 hrs (5 days) at 25 °C(P.R. Fisk, 1993), which is less than the 40 day criteria for (fresh) water. A similar hydrolysis kinetic (t_½=12.3 days at 20°C) was observed in the enhanced ready test (Harlan Laboratories, 2010). This rate describes the hydrolysis of the epoxy group to form a diol. It is anticipated that other constituents or impurities that contain an epoxy group will hydrolysis at the same or a very similar rate. Not P based on Annex XIII of REACH.

For the product of hydrolysis (di-diol) only minimal mineralization was observed over the course of 28 days ready test with the REACH substance following the OECD 301protocol (Harlan Laboratories, 2010). It is anticipated that hydrolysis products of the other constituents including constituent C will likely not be readily degradable. In the absence of further information the following conclusion is drawn for the hydrolysis product:P based on screening criteria.

Bioaccumulation assessment: No relevant experimental data on bioconcentration of BADGE in an aquatic or any other species has been identified. The octanol-water partition coefficient has been determined in a modified shake flask test as log P_ow=3.24(25 °C). Bioaccumulation potential has been assessed in-silico (CATABOL BCF baseline model v. 1.02) for BADGE and the product of hydrolysis (The Dow Chemical Company, 2010b). The bioconcentration of BADGE is predicted to be significantly diminished when compared to a passive diffusion model due to the rapid hydrolysis of the epoxy group to form the diol which is likely followed by o-Glucuronidation to the terminal alcohol group and excretion. While the constituents are not fully within the domain of the model, the predicted metabolism is observed in the ADME studies in mice (Shell Toxicology Laboratory, 1978a; Shell Toxicology Laboratory, 1979; Shell Toxicology Laboratory, 1983).The predicted BCF is 31 for the main constituent (n=0) and 13 for the constituent with n=1. The impurities with an epoxy group are anticipated to follow the same hydrolysis and glucuronidation pathway and have a low potential of bioconcentration. Conclusion: Not B based on screening criteria.

Toxicity assessment: Theacute aquatic toxicity data sets available for fish, invertebrates and algae, and a chronic toxicity study with the freshwater invertebrate,Daphnia magnaand algae.For fish, the 96-hour LC50 value of 1.3 mg/L for BADGE and BADGE-related resins was derived as the geometric mean of 96-hour LC50 values taken two studies with rainbow trout (Oncorhynchus mykiss). For invertebrates, the 48-hour EC50 value of 2.1 mg/L was derived as the geometric mean of two 48-hour EC50 values withDaphnia magna.For the chronic invertebrate study withD. magna,the 21-day NOEC (based on survival, growth and reproduction) was 0.3 mg/L. In a growth inhibition test withScenedesmus capricornutum,the 72-hour E_rC50 was > 11 mg/L, which was the limit of solubility for BADGE, and the 72-hour NOEC (based on growth rate) for BADGE and BADGE-related resins was determined to be 4.2 mg/L.

BADGE is neither classified as carcinogen, nor as mutagen, repro toxicant, T-R48, nor Xn-R48.

Conclusion: not T based on Annex XIII of REACH.