tert-pentyl 2-ethylperoxyhexanoate

Endpoint summary

Description of key information

The most sensitive endpoint for the most sensitive species currently available for the terrestrial compartment is a NOEC of 1.37 mg/kg DW for sugar beet species. No other terrestrial endpoints are available at present. The ready biodgradable profile of the substance and the log KOC of 3.24 would suggest that the substance will likely not reach, therefore accumulate in or strongly adsorb to the soil.

Additional information

Based on the physical chemical profile of the substance it is not considered as highly adsorptive due to having a Log KOC of 3.24. In addition the substance is readily biodegradable and is used soley for industrial purposes and will therefore always pass water treatment before release to the environment. Soil (and sediment) are therefore not expected to be compartments of concern for this substance.

However, it should be noted chemicals could reach the soil via several routes:

 

1.  Application of sewage sludge in agriculture.

Although not common practice, application of sewage sludge in agriculture cannot be completely excluded. Due to the readily biodegradable properties of the test material exposure to soil via this route is not expected.

Regarding the rest of the lifecycle, organic peroxides are mainly used as cross-linking agent/polymerization initiator for the production of resins/rubbers/polymers. Based upon the fact that these processes take place at high temperatures far in excess of the SADT, organic peroxides are totally consumed during this process (>99%). Processes are in addition water-free (so no production of sewage sludge), it is assumed that the soil is not exposed to organic peroxides in the rest of the lifecycle.

 

 2. Direct application of chemicals.

Based on the uses inventoried for organic peroxides we can consider that there is no direct application of these substances on the soil compartment. Hereunder, the relevant Environmental Release Categories (ERC), as described in guidance R12 (version 2.0, dated 7/11/2010)

 

3. Deposition from the atmosphere.

Deposition from the atmospheric compartment involves volatilization, vaporization or direct release of a considered substance into the atmosphere. Due to their dangerous intrinsic physico-chemical properties, organic peroxides are carefully handle in closed systems and their transport and production are ruled by several regulations. Based on organic peroxides uses too, we may assume thatdeposition on soil from the atmosphere is unexpected.

 

Based on the above justifications there is likely no exposure to soil. However, as complete absence of exposure to soil is at this stage not possible to conclude, one soil test has therefore been conducted to make PNEC calculation possible. Based on ECHA guidance R 7c, the substance is a soil hazard category 2 (Log Kow <5, Readily biodegradable but toxic). A short term test on the most sensitive species from the aquatic assessment is then suggested in the guidance. Based on aquatic testing, algae is the most sensitive species. The registrant has conducted an OECD 208 using 6 different species.

The PNEC derived from this study is similar to the one derived with the Equilibrium Partitioning Method and does not show risk for any of the uses (PEC/PNEC < 1), therefore no further testing is proposed.