1,2,4-Benzenetricarboxylic acid, mixed branched tridecyl and isodecyl esters

Toxicity to terrestrial plants

Description of key information

Toxicity to terrestrial plants - read-across data (2 key studies in lettuce and ryegrass)
Read-across results with surrogate indicate that the submission substance, CAS No. 70225-05-7, is not expected to produce toxicity to terrestrial plants at high soil loading rates (> 8551 mg/kg and >8630 mg/kg). 

Additional information

No terrestrial plant toxicity data are available for the submission substance, CAS No. 70225-05-7, or related trimellitate esters. However, short-term terrestrial plant toxicity studies have been reported for the diisodecyl phthalate (DIDP) (CAS No. 68515-49-1) which can provide some useful read-across assessment for the trimellitates.

As discussed previously, from a structure activity relationship perspective, the long-chain alkyl phthalates and the corresponding long-chain trimellitates are chemically similar or related in that they are benzene dicarboxylic or tricarboxylic acid ester analogs of each other. Hence, in the absence of trimellitate surrogate data, available data for the corresponding phthalate esters of similar chain-length, like DIDP, may be considered as an alternative read-across surrogate to help in estimating the potential terrestrial toxicity of the submission substance, CAS No. 70225-05-7, which is a trimellitate with two C10 and one C13 group). See additional discussion in CSR document.

 

The toxicity of the read-across surrogate, diisodecyl phthalate (DIDP) (CAS No. 68515-49-1) as measured by effects on emergence or growth to lettuce and ryegrass was evaluated in a 5-day terrestrial plant toxicity test. Results indicated that DIDP had no observed effect on germination of lettuce (Lactuca sativa) or ryegrass (Lolium species) in the 5-day plant toxicity test in natural or artificial soil. The 5-day EC50 values were >8630 mg/kg (dw) in natural soil and > 8551 mg/kg measured (dw) in artificial soil for both plant species. The 5-day NOEC values also were >8630 mg/kg (dw) in natural soil and > 8551 mg/kg measured (dw) in artificial soil for both plant species. Collectively, these findings indicate that the DIDP does not cause acute toxicity to terrestrial plants at high soil concentrations (e.g., as high as 8630 mg/kg (dw).  

 

Based on the above read-across toxicity data, the submission substance, CAS No. 70225-05-7, would not be expected to cause toxicity or adverse effects to terrestrial plants in soil.