Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

ENVIRONMENTAL FATE PROPERTIES

Summary of degradation

FeMn slag is an inorganic substance and hence the ready biodegradation and hydrolysis tests are not relevant. This is because there is no carbon to be evolved and no chemical bonds to be broken, respectively. A transformation dissolution study has shown that the concentration of manganese released from the powdered substance is 199.7 µg/L after 28 days from 1mg/L loading). This is more than the background concentration of manganese in European environments (15.9 µg Mn/L in surface water, 452 mg/kg in sediment, 428.6 mg/kg in soil). However, the substance exists as rocks of predominantly 1-10cm in diameter rather than a powdered form and hence in realistic conditions potential for transformation /dissolution of the manganese fraction will be very much lower.

 Volatilisation

Data on volatilisation are not available for the substance.FeMn slag itself is a solid substance existing as rocks of predominantly 1-10cm in diameter and hence not volatile.

Distribution modelling

No distribution modelling data exist

Summary of environmental distribution

 

A transformation dissolution study has shown that the concentration of manganese released from the powdered substance is 199.7 µg/l after 28 days from 1mg/L loading). However, the substance exists as rocks of predominantly 1-10cm in diameter rather than a powdered form and hence in realistic conditions potential for transformation /dissolution (and hence bioavailability) of the Manganese fraction will be very much lower. The 72hr adsorption/desorption study (OECD 106) on MnCl2 (a more soluble/readily available form of Manganese (Mn2+)) in 35 different soil types illustrate that adsorption is pH sensitive. A median Kd of 994 ml/g was determined for all soil types used (pH range 3.0-8.5).

 

Summary and discussion of bioaccumulation

No experimental data on bioaccumulation exist. A transformation dissolution study has shown that the concentration of manganese released from the powdered substance is 199.7 µg/l (after 28 days from 1mg/L loading). This is more than the background concentration of manganese in European environments (15.9 µg Mn/L in surface water, 452 mg/kg in sediment, 428.6 mg/kg in soil). However, the substance exists as rocks of predominantly 1-10cm in diameter rather than a powdered form and hence in realistic conditions potential for transformation /dissolution (and hence bioavailability) of the manganese fraction will be very much lower.Furthermore, manganese is an essential trace nutrient in animals and is required for the photosynthetic process in plants. Hence unacceptable bioaccumulation is highly unlikely to occur in any organism due to their ability to regulate intake and loss from natural sources.

Secondary poisoning

Bioaccumulation of FeMn slag is not expected to occur. Hence no secondary poisoning risk exists.

Assessment of PBT/vPvB Properties - Comparison with the Criteria of Annex XIII

According to the Guidance on information requirements and chemical safety assessment, Chapter R.11: PBT assessment, “the PBT and vPvB criteria of Annex XIII to the regulation do not apply to inorganic substances”. Therefore FeMn slag is not considered to require any further assessment of PBT properties.