Reaction mass of 2,2'-[methylenebis(2,1-phenyleneoxymethylene)]bis(oxirane) and 2,2'-[methylenebis(4,1-phenyleneoxymethylene)]bis(oxirane) and 2-({2-[4-(oxiran-2-ylmethoxy)benzyl]phenoxy}methyl)oxirane

Endpoint summary

Additional information

The read across to BPFDGE from BADGE (CAS#1675-45-3, EC#216-823-5) is appropriate for this endpoint as there are many study results, including phys/chem, ecotoxicology and mammalian toxicology, that indicate similar characteristics. One long term test with Daphnia magna was conducted with BADGE. This test was deemed reliable and useful for risk assessment (Klimisch score = 2). In this test, D. magna were exposed to five concentrations of Epikote 828 ranging from 0.03 - 3 mg/L and control dilution water for 21 days in a static renewal test design. Survival, growth, and reproduction rate were all significantly reduced at 1 mg/L of Epikote 828, but were all unaffected at 0.3 mg/L. The freshwater PNEC is derived from this study with an assessment factor 100 to give a value of 0.003 mg/L for freshwater organisms. Likewise a microorganism study was examined from BADGE and deemed reliable and useful for risk assessment. The study examined the response of respiration inhibition of activated sludge over a 3 hour exposure period. The activated sludge inhibition test reported a 3 -hour IC20, IC50 and IC80 all >100 mg/L BADGE. Furthermore, inhibition of respiration did not exceed 10% at the highest dose level (nominal) of 109 mg/L BADGE. The value of 100 mg/L was selected as the key parameter for this endpoint.

For acute toxicity there are multiple studies for each endpoint that have been performed with the substance described as “formaldehyde, oligomeric reaction products with 1-chloro-2,3-epoxypropane and phenol (CAS# 9003-36-5), Depending of the conditions of the reaction, the formation products can results oligomers up to the polymer molecular weight range and structure.

 

The products tested for acute toxicity in daphnia, algae and fish are a range of these oligomers, EPIKOTE 862 on the low molecular weight end and the TK 12225/D, DEN 438 and EPIKOTE 155 on the higher end of molecular weights. GPC of these substances are virtually identical with only slight indications to molecular weight range. The EPIKOTE 862 studies had high loading rates and a long mixing time, which had the potential to selectively extract more soluble impurities that could be more toxic. The study with DEN 438 and TK 12225/D both used a solvent to create the test solutions, which created a cloudy suspension not necessarily representative of the toxic action of the substance. Some of the suspension at higher loading rate was observed to precipitate out. The EPIKOTE 155 study used a high loading rate (1000 mg/L) generate test solutions. The actual concentrations were not measured as the amount soluble in water would be below the level of detection. Even at this high loading rate there was insufficient test material solved in the test solution to exhibit any toxicity.

 

To reconcile these studies and develop a dose descriptor for the endpoints, the appropriate studies with the products EPIKOTE 862, DEN 438 and TK 12225/D have been averaged in a weight of evidence approach to and the EPIKOTE 155 studies are used as a supporting studies.