N,N'-ethylenebis(3,4,5,6-tetrabromophthalimide)

PBT assessment

PBT assessment: overall result

Reference

Name:

1,2-Bis-(tetrabromophthalimido)ethane

Type of composition:

legal entity composition of the substance

State / form:

solid: particulate/powder

Reference substance:

1,2-Bis-(tetrabromophthalimido)ethane

PBT status:

the substance is not PBT / vPvB

Justification:

Persitence. EBTBP has extremely limited solubility. For example, its estimated water solubility is 3.02 e-9 mg/L and its octanol solubiity as measured by total bromine content is approximately 0.45-0.60 mg/L. This limited solubility negatively affects its susceptibility to degradation. EBTBP is expected to have very limited availability to environmental bacteria, and, thus, degradation by this organisms will be limited by this fact alone. EBTBP is not readily biodegradable in the MITI test. A Level III Fugacity Model, based on chemical structure alone, estimates half-lives of 6.5 hr (air), 4320 hr (water), 8640 hr (soil) and 38900 hr (sediment) following emissions of 1000 kg/hr to each of air, water and soil. Overall persistence time is estimated at 5510 hrs or 7.6 months. That is, reaction with hydroxyl radicals in air is expected, and hydrolysis in water or biodegradation in soil and sediment is not expected. However, EBTBP has negligible vapor pressure such that degradation in air is not expected to be a significant route of environmental degradation. Further, EBPTBP's negligible water solubility,and limited paritioning to water indicate persistence in that media will not contribute substantially to its overall environmental persistence. EBTBP is expected to partition predominantly to soil, where it is expected to be very persistent (vP).

Bioaccumulation. EBTBP's insolubility, large molecular size, high molecular weight, and folded confrimation adversely affect its bioavailability. EBTBP's solubility in 1-octanol at room temperature, 0.45 -0.60 ppm, is less than 0.002 mmol/L x MW (REACH Guidance, Capter R11, page 32) or 1.90 mg/L. Based on this, EBTBP is not expected to accumulate in lipids. Additionally, EBTBP’s molecular weight is >700 and its maximum length ranges from 16.8 to 20 angstroms provides additional evidence for a lack of bioaccumulation. EBTBP did not bioconcentrate in fish when exposed via water.

Toxicity. EBTBP was not acutely toxic to orange-red killifish in a 48 hr test performed in Japan (LC50>500 ppm). EPI(v4.0) predicts EBTBP will not be acutely or chronically toxic to aquatic organisms due to its insolubility. No effects at saturation are predicted. EBTBP's estimated Log Kow is 9.79, which puts it above the cutoff value (Log Kow > 8.0) for toxicity. The estimates were based on the chemical structure alone. Additionally, no adverse effects were observed in prenatal developmentals sudies in rats and rabbits at doses up to 1000 mg/kg bw/d or in a 90-d study in rats at doses up to 1% in the diet. EBTBP is not classified as a carcinogen, mutagen or reproductive hazard.

Likely routes of exposure:

The most likely route of exposure is in the workplace via inhalation when bulk bags of the product are emptied.