Residues (petroleum), steam-cracked light

Ecotoxicological Summary

Additional information

Experimental data provided for this Category was generated via use of WAFs. Deriving PNEC’s for UVCB substances based on WAF information is inappropriate. PNECs were derived using the PETROTOX v.3.05 model.The hydrocarbon block method is used for environmental risk assessment (see REACH guidance, R7, app.13-1). PNECs for hydrocarbon blocks have been derived using the HC5 statistical extrapolation method and the target lipid model using representative structures. See Product Library tab in PETRORISK spreadsheet (Table B.3). Given the large database of organisms included in the target lipid model, an assessment factor of one has been applied to the HC5.

 

Conclusion on classification

Some ecotoxicology studies are available for this category. The most sensitive endpoint was a 96 hour LC50 for fish of 1mg/l WAF.

Ecotoxicity Labelling for Fuel Oils Category

Studies were conducted to standard guidelines and according to GLP and are considered reliable for use as key/supporting studies. The authors report the LC50 based both 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 sensitivity was seen over the three trophic levels. Fish had LL50 range of 1.1 to 32 mg/l; Invertebrates had EL50 range of 3.3 – 13 mg/l; Algae had ErL50 range 2.3-8.95mg/l.

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. Based on the available data the most sensitive result from each taxa falls between 1 to 10 mg/l WAF. Therefore streams in this category should have the classification R51/53 under the DSD and Chronic Cat 2 under the CLP regulations.

The measured partition coefficients of four streams within this category have log Kow ranges from 3 and <6.5. Therefore, the classification cannot be removed.

Conclusion

Based on the available experimental data streams in this category should have the classification R51/53 under the DSD and Chronic 2 under the CLP regulations.

However, the classification of streams in this category may be impacted by other constituents. Components which may impact the classification (i.e. those that are R50/53) 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 below. 

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%.