Registration Dossier
Registration Dossier
Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.
The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.
Use of this information is subject to copyright laws and may require the permission of the owner of the information, as described in the ECHA Legal Notice.
EC number: 284-957-1 | CAS number: 85005-25-0
Toxicity to soil microorganisms
Administrative data
Link to relevant study record(s)
Description of key information
The chemical safety assessment according to Annex I of Regulation (EC) No. 1907/2006 does not indicate the need to investigate further the toxicity to soil microorganisms.
Key value for chemical safety assessment
Additional information
No experimental data investigating the effects on soil microorganisms are available for the NPG esters. Therefore, all available related data is combined in a Weight of Evidence (WoE) approach, which is in accordance to the REACh Regulation (EC) No 1907/2006, Annex XI, 1.2, to adapt the data requirements of Regulation (EC) No 1907/2006 Annex VII - X (ECHA, 2012).
In the absence of a clear indication of selective toxicity, an invertebrate (earthworm or collembolan) test is preferred, as outlined in ECHA guidance section R.7.11.5.3.A long-term study according to OECD Guideline 222 is available for the NPG ester 2,2-dimethyl-1,3-propanediyl dioleate (CAS No. 42222-50-4). 2,2-dimethyl-1,3-propanediyl dioleate has the highest adsorption potential based on Koc. No effects were observed at the test concentration of 1000 mg/kg dw in this study. And due to the structural similarity, other NPG esters are also not expected to have effects on terrestrial macroorganisms.
Further justification is given within the category justification in IUCLID section 13.In addition, no effects were observed on activated sludge microorganisms with Heptanoic acid, ester with 2,2-dimethyl-1,3-propanediol (CAS No. 68855-18-5), which isthesmallest and thereby most bioavailable member of the NPG group.Moreover, in a chronic study on Daphnia magna, available for the NPG ester 2,2 -dimethyl-1,3 -propanediyl dioleate (CAS No. 42222 -50 -4), no long-term effects were observed at the test concentration of 1 mg/L, which is far above the water solubility of the NPG esters.
The Guidance on information requirements and chemical safety assessment, Chapter R.7c: Endpoint specific guidance (ECHA, 2012) states that a test on soil microbial activity will only be additionally necessary for a valid PNEC derivation if inhibition of sewage sludge microbial activity has occurred, and this is clearly not the case. Since the NPG esters are readily biodegradable, they will be degraded quickly. Thus, acute tests with earthworm in combination with chronic aquatic data and toxicity data on microorganisms indicating no effects up to the limit of water solubility are sufficient to assess that the NPG esters have a very low toxicity to terrestrial organisms.
This is supported by further evidence from literature data. This data showed that soil microorganism communities are well capable of degrading fatty acid esters (Hita et al., 1996 and Cecutti et al., 2002) and use them as energy source (Banchio & Gramajo, 1997). Hita et al. investigated the degradation of the model molecule tristearin which is a triglyceride containing of glycerin tri-esterified with stearic acid in three different soils for 4 weeks. The amount of stearic acid increased in considerable amounts during the experiment showing the hydrolytic activity of lipases breaking the ester bonds. The investigation of ester fractions moreover showed the generation of new alkanoic acids (methyl stearate, ethyl stearate and propyl stearate) which were not determined in the controls. Nevertheless the amounts were no longer present after 4 weeks, which leads to the assumption that degradation by soil microorganisms had occurred. The same was shown by Cecutti et al. (2003). One soil sample was chosen and incubated with methyl oleate (plant oil) for 120 d. Methyl oleate and its metabolites were completely degraded after 60 d. Streptomyces coelicolor, a common gram-positive soil bacterium uses fatty acids (C4-C18) as sole carbon end energy source indicating that fatty acids are not-toxic and can be used for catabolism (Banchio and Gramajo, 1997). The available literature data shows that soil microorganisms are capable to break-up ester bonds and degrade fatty acids in significant amounts. Moreover, the data indicated the non-toxic properties of fatty acids since they can be used as energy source.
Based on the available data, terrestrial toxicity is not of concern for NPG esters.
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.
Reproduction or further distribution of this information may be subject to copyright protection. Use of the information without obtaining the permission from the owner(s) of the respective information might violate the rights of the owner.
