Distillates (petroleum), cracked stripped steam-cracked petroleum distillates, C10-12 fraction

Ecotoxicological Summary

Additional information

Deriving PNEC’s for UVCB substances based on WAF information is inappropriate therefore the PNEC has been derived using the Petrotox model for this Category. This category contains members with a carbon number range up to C15. The model was run until the calculated aliphatic PNEC was below the level of solubility. This occurred at a carbon number of C13 and the aliphatic boiling point range 195-240 °C. Based on this information the PNEC aqua aliphatic derived was 0.001mg/l. For C13 aliphatic compounds Petrotox v3.05 calculates an indicative HC5 of 0.001mg/l. For C15 aromatic compounds Petrotox v3.05 calculates an indicative HC5 of 0.002mg/l.

 

Soil and sediment PNEC’s were derived using the aquatic PNEC and using the equilibrium partitioning method.

 

The HC5 model states that it is expect that substances with a Log Kow higher than 5 will not pose a toxicity hazard to other WWTP microbes due to solubility and organism constraints, therefore only an aromatic STP PNEC was derived.

Conclusion on classification

Tested streams

Some ecotoxicology studies are available for CAS numbers 94733-07-0, 68477-40-7. 68478-10-4 and 68477-54-3. The studies showed similar results across the three trophic levels. Two fish studies provided a 96 hr LL50 range between 0.73 – 6.3 mg/l (96 hr LC50 ranged from 0.58 – 58.6mg/l in 5 studies). Two invertebrate studies provided 48 hr EL50 range of 0.91 – 3.2 mg/l (48 hr EC50 ranged 0.76-2.9mg/l). Two 72 hr algae studies provided a 72 hr ErL50 range of 1.3-1.5 (72 hr ErC50 ranged 0.84-1.4 mg/l).

No other stream toxicity data has been submitted.

Ecotoxicity Labelling for Resin Oils and Cyclic Dienes Category

Data on the acute aquatic toxicity of 5 members of this category was obtained from proprietary sources. No data was identified in the published literature. The data from these streams has been read across to the other category members.

The studies were conducted to standard guidelines and according to GLP and so are considered reliable for use as key studies. For some of the studies, the authors report the LC50 based on nominal loading rates (WAF) and mean measured concentrations. As the test substance is a hydrocarbon stream with various components reporting a measured concentration could be misleading as the measured concentration does not relate to a concentration of the raw stream. Instead, we have used the results reported as WAF, which better represent the potential toxicity of the test substance. Similar sensitivities were shown in all three trophic levels.

WAF data can be used for comparison with the criteria for environmental classification under both the DSD and CLP Regulations. However, its use must be considered carefully. It is considered that based on the available data, (Fish 96 hr LL50 0.73mg/l) streams in this category should have the classification R50/53 under the DSD and Acute 1 Chronic 1 under the CLP regulations.

The measured partition coefficients of three streams in this category have log Pow ranges from 2.8 ->6.5. Therefore the classifications cannot be removed.

Conclusion

Based on the available experimental data streams in this category should have the classification R50/53 under the DSD and Acute 1 Chronic 1 under the CLP regulations.

APPENDIX I

The table below lists the main components of the streams in this category, together with their environmental classifications. Components which are not in this table should be identified by the registrants and the impact of their environmental classification included in the assessment. The classification of each stream can be determined following the equations given in the notes section under the table.

Acute	Min	Max	Substance Label
Benzene		40	Not classified for Environment
Toluene		<22	Not classified for Environment
1,3 – butadiene		0.2	Not classified for Environment
Isoprene		1.5	N:R52-53 Aquatic Chronic 3 H412
Naphthalene/methyl-naphthalene		40	N: R50-53 Aquatic Chronic 1 H410 Aquatic Acute 1 H400
Other identified components
Indene		30	Not classified for Environment
Styrene/Methylstyrene		20	Not classified for Environment
Note:  Under the DSD R50/53 applies if sum of components with R50/53 is >25%. R51/53 applies if sum of components with R51/53 is >25% or if sum of components with R50/53 is >2.5%. R52/53 applies if sum of components with R52/53 is >25% or if sum of components with R51/53 is >2.5% or if sum of components with R50/53 is >0.25%.   Under the CLP Regulations Acute 1 applies if sum of components with acute 1 is >25%. Chronic 1 applies if sum of components with chronic 1 is >25%. Chronic 2 applies if sum of components with chronic 1 multiplied by 10 plus the sum of components with chronic 2 is >25%. Chronic 3 applies if sum of components with chronic 1 multiplied by 100 plus the sum of components with chronic 2 multiplied by 10 plus the sum of components with chronic 3 is >25%. Chronic 4 applies is sum of components with chronic 1, 2, 3 and 4 is >25%.