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Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Adsorption / desorption:

The adsorption coefficient Koc in soil and in sewage sludge 4-Nonylphenol, branched, ethoxylated(CAS No.127087-87-0) was determined by the Reverse Phase High Performance Liquid Chromatographic method according to OECD Guideline No. 121 for testing of Chemicals. The reference substances were chosen according to estimated Koc range of the test substance and generalized calibration graph was prepared. The chosen reference substances were having Koc value ranging from 1.239 to 2.47. The Log Koc value was found to be 2.6311 ± 0.0001 at 25°C.

Additional information

Adsorption / desorption:

Four studies for adsorption in soil/sediment endpoint including experimental and valid predicted model data of test chemical 4-Nonylphenol, branched, ethoxylated (Cas no. 127087-87-0) with relevant read across chemicals which is 90-80 % structurally similar to target were reviewed as follows:

 

First study from experimental report of UERL (2017) indicates that the adsorption coefficient Koc in soil and in sewage sludge 4-Nonylphenol, branched, ethoxylated(CAS No.127087-87-0) was determined by the Reverse Phase High Performance Liquid Chromatographic method according to OECD Guideline No. 121 for testing of Chemicals. The reference substances were chosen according to estimated Koc range of the test substance and generalized calibration graph was prepared. The chosen reference substances were having Koc value ranging from 1.239 to 2.47. The Log Koc value was determined to be 2.6311 ± 0.0001 at 25°C.

And supporting data of target indicate the Soil Adsorption Coefficient i.e Koc value of 4-Nonylphenol, branched, ethoxylated was estimated using EPI suite KOCWIN Program (v2.00) as Koc 1035 L/kg(log Koc=3.014) by means of MCI method at 25 deg.C. This Koc value indicates that the substance 4-Nonylphenol, branched, ethoxylated has a moderate sorption to soil and sediment and therefore have slow migration potential to groundwater.

 

Whereas experiment result (HSDB database by US EPA) for read across chemical 4-Nonylphenol, ethoxylated (Cas no. 26027-38-3) indicate that using a structure estimation method based on molecular connectivity indices, the Koc of 4-Nonylphenol, ethoxylated can be estimated to be 1300 This estimated Koc value suggests that 4-Nonylphenol, ethoxylated is expected to have low mobility in soil.

 

Study from another read across substance Nonylphenol, ethoxylated (Cas no. 9016-45-9) suggest that the Adsorption of nonylphenol polyethoxylates is dependent upon the number of ethoxylate units present; Sludge adsorption was greatest for nonylphenol (44-48% of the added compound adsorbed) followed by nonylphenol ethoxylate (n=1) (14-15% of the added compound adsorbed to sludge), and nonylphenol diethoxylate (67% of the added compound adsorbed to sludge). Adsorption of nonylphenyl ethoxylate (n=6) to sediment was dependent on the organic matter concentration. A Koc of 6.1 was measured in sediment. Polyethyleneglycol nonylphenyl ether (n=13) was observed to Kd values ranging from 450-1460 L/kg in sediment, 230-590 L/kg in sediment without organic carbon, 25-92L/kg in silica, and 12000-13000 L/kg in sludge, suggesting strong sorption may occur to the solid phase in soil.

 

Thus all above studies for target and read across reports from authorative databases arrive at a conclusion as the test substance 4-Nonylphenol, branched, ethoxylated (Cas no. 127087-87-0) has low mobility in soil/sediment compartment.