OO-tert-butyl O-(2-ethylhexyl) peroxycarbonate

Toxicity to birds

Administrative data

Endpoint:

long-term toxicity to birds

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

other:

Justification for type of information:

The performance of a test on toxicity to birds is considered not scientifically justified. REACH Regulation No 1907/2006, Annex X, Sect. 9.6.1, Col. 2, states the following:
“Any need for testing should be carefully considered taking into account the large mammalian dataset that is usually available at this tonnage level.”

Direct and indirect exposure of the peroxyesters to soil is highly unlikely. Based on exposure assessment, release rates to the soil and air compartment are considered to be 0 %. Application of STP sludge to agricultural soil is not supported. All peroxyesters of this group are used at industrial settings only. There are no widespread or wide-dispersive uses foreseen for these substances.

Due to the unstable nature of organic peroxides, it can be assumed that upon contact with water and organic matter, the substances undergo hydrolytic degradation resulting in the formation of respective alcohols and acids. In addition, the subsatnce was shown to be readily biodegradable. Thus, toxicity testing on soil organisms was considered not scientifically justified. This is confirmed by the following argumentation:

1. Application of sewage sludge in agriculture.
Organic peroxides, when released into the sewage of a production plant or a downstream user’s plant, are treated with other substances in dedicated sewage treatment plants. The activated sludge stemmed from these sewage treatment plants are then extracted and treated as chemical waste. From the production plant, the release of organic peroxide into the sewage is very limited, not to say completely negligible. The waste water from production plant can be treated on site (at least a physical/chemical treatment, which will neutralize potential residual organic peroxide), which is usually followed by a biological treatment. Therefore, it is expected that organic peroxides are not present in sludge. Furthermore, application of sludge to soil is excluded for industrial uses.
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 organic peroxides are totally consumed during the process (>99 %, which is confirmed by the release factor to sewage for curing agents from OECD Emission Scenario Document (ESD) on Plastic Additives, n°3, 2009), the soil is not exposed to organic peroxides via use of sludge.
As a consequence, soil is not exposed to organic peroxyesters.

2. Direct application of chemicals. Based on the uses inventoried for organic peroxides there is no direct application of these substances on the soil compartment. Indeed, all uses are within controlled industrial settings.

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 handled in (semi-)closed systems and their transport, production and use are strictly controlled. This is also in line with the release factor to the atmosphere for curing agents from ESD n°3. Thus, deposition on soil from the atmosphere is not expected.

Therefore, the Chemical Safety Assessment does not indicate the need to further assess the toxicity to birds. Especially because a comprehensive dataset on toxicity to mammals is available or has been porposed (OECD 414 in rabbits and OECD 443) covering human health endpoints. Based on these arguments no tests are proposed for toxicity to birds also considering animal welfare reasons.
Based on the low bioaccumulation potential of the substance, secondary poisoning can be excluded and the PNEC on secondary poisoning could be waived according to ECHA Guidance Document CSA&IR, R.10, 2008. Therefore, no study of the toxicity of birds is needed as a starting point for the derivation of the PNEC secondary poisoning.