Trihexyl benzene-1,2,4-tricarboxylate

Ecotoxicological Summary

Conclusion on classification

Conclusion on Classification:

In the absence of adequate aquatic chronic toxicity information from all three trophic levels, the classification was based on the available short-term aquatic toxicity values from laboratory experimental studies on two trophic levels (algal growth inhibition test; acute daphnid immobilisation test) conducted on an analogue source substance through read-across (i.e.,tris(2-ethylhexyl)benzene-1,2,4-tricarboxylate (trioctyl trimellitate; TOTM; CASRN 3319-31-1). No observed toxicity was recorded in either test (72-h NOEC ≥ 100 mg/L in algae; 48-h NOEC ≥ 180 mg/L in daphnids). The maximum test concentration in each test (100 mg/L in algae, 180 mg/L in daphnids) exceeded the water solubility limits of the source substance (0.13 mg/L) as well as the target substance (3.33E-05 mg/L). Therefore, acute toxicity was not observed at the water solubility limits. The substance has not been shown to be readily biodegradable in a CO₂ evolution test conducted on the target substance (52.9% degradation reported in 28 days and 77.5% degradation in 40 days), although the substance did exhibit inherent, ultimate biodegradability and substantial mineralisation. The target substance has an estimated octanol-water partition coefficient of log Kow = 8.87 (based on QSAR modeling). Therefore, the substance has been classified as Category Chronic 4.