Registration Dossier

Ecotoxicological information

Toxicity to microorganisms

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

Toxicity to microorganisms - read across data using surrogate material. 
Results of read-across ASRIT study indicate that the submission substance is not expected to produce any toxicity to activated sludge bacteria or microorganisms at is maximum water solubility limit.

Key value for chemical safety assessment

Additional information

No short-term studies assessing toxicity potential to activated sludge (sewage) micro-organisms have been reported for the submission substance, CAS No. 70225-05-7 or its related trimellitate esters.  However, read-across microbial inhibition (e.g., OECD 209, activated sludge respiratory inhibition or ASRIT ) toxicity data are available di-isodecyl phthalate (DIDP) (CAS No. 68515-49-1) which can provide some useful read-across assessment for the trimellitates.

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 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). Justification and rationale for read-across are discussed in more detail in the CSR document (see Section 7.2.1.1).

 

An activated sludge respiration inhibition test (OECD 209) has been carried out with the read-across surrogate, diisodecyl phthalate (DIDP) (CAS No. 68515-49-1). Findings indicate that DIDP was not inhibitory to sludge respiration at the highest test loading of 100 mg/L loading (83.3 mg/L measured).  Therefore, DIDP is not expected to cause toxicity to micro-organisms or to impact microbial activity in activated sludge inoculum or in a wastewater treatment plant. 

 

Based on the read-across ASRIT findings for DIDP and the structural similarity relationship (e.g., aromatic esters, low water solubility) between the materials, the submission substance, CAS No. 70225-05-7, would not be expected to be toxic to seawage microorganisms at its maximum water solubility limits.