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(RAC) Committee for Socio-Economic Analysis (SEAC) Background Document Committee for Risk Assessment (RAC) Committee for Socio-economic Analysis (SEAC) Background Document to the Opinion on the Annex XV dossier proposing restrictions on Calcium cyanamide ECHA/RAC/RES-O-0000006784-64-01/F ECHA/SEAC/[Opinion No (same as opinion number)] EC Number CAS Number 205-861-8 156-62-7 Draft 11 June 2020 P.O. Box 400, FI-00121 Helsinki, Finland | Tel. +358 9 686180 | echa.europa.eu BACKGROUND DOCUMENT TO THE RESTRICTION REPORT ON CALCIUM CYANAMIDE CONTENTS 1. Summary ................................................................................................................. 1 2. Report ...................................................................................................................... 5 3. The problem identified ................................................................................................ 5 3.1. Introduction .......................................................................................................... 5 3.2. Hazard, exposure/emissions and risk........................................................................... 7 3.2.1. Identity of the substance(s), and physical and chemical properties ............................... 7 3.2.2. Classification and labelling ................................................................................ 10 3.2.3. Reliability of the studies cited in this report ........................................................... 10 3.2.4. Fate, behaviour and transformation in the environment ............................................ 11 3.2.5. Summary of fate, behaviour and transformation of calcium cyanamide in the environment 11 3.2.6. The fate, behaviour and transformation of PERLKA® and calcium cyanamide in the environment .......................................................................................................... 12 3.2.7. The transformation of cyanamide and its transformation products in the environment ...... 13 3.2.8. Bioaccumulation ............................................................................................. 16 3.2.9. Hazard assessment ......................................................................................... 17 3.2.10. Exposure assessment ..................................................................................... 30 3.2.11. Risk characterisation ...................................................................................... 49 3.3. Justification for an EU wide restriction measure ............................................................. 62 3.4. Baseline.............................................................................................................. 63 3.4.1. Manufacture and uses ...................................................................................... 63 3.4.2. Impact on the environment from the use of calcium cyanamide as a fertiliser ................. 65 4. Impact assessment ................................................................................................... 66 4.1. Introduction ......................................................................................................... 66 4.2. Risk management options ....................................................................................... 67 4.3. Proposed restriction ............................................................................................... 69 4.3.1. Justification for the selected scope of the proposed restriction .................................... 70 4.3.2. Enforcement conditions and entry into force .......................................................... 71 4.4. Response to the restriction scenario ........................................................................... 71 4.4.1. Alternatives ................................................................................................... 72 4.5. Economic Impacts ................................................................................................. 73 4.5.1. Economic impacts on end users .......................................................................... 74 4.6. Environmental and human health impacts ................................................................... 78 4.6.1. Benefits of the proposed restriction for the environment ........................................... 78 P.O. Box 400, FI-00121 Helsinki, Finland | Tel. +358 9 686180 | echa.europa.eu BACKGROUND DOCUMENT TO THE RESTRICTION REPORT ON CALCIUM CYANAMIDE 4.7. Wider impacts ...................................................................................................... 80 4.7.1. Impacts on the Registrant ................................................................................. 80 4.8. Practicability and monitorability ................................................................................ 81 4.9. Proportionality to the risk ........................................................................................ 81 4.9.1. Affordability .................................................................................................. 82 4.9.2. Cost-effectiveness .......................................................................................... 82 4.10. A short description of potential restriction option two .................................................... 83 5. Assumptions, uncertainties and sensitivities ................................................................. 86 6. Conclusion ............................................................................................................... 87 7. References ............................................................................................................... 89 Annex B. Information on hazard and risk ....................................................................... 100 B.1. Identity of the substance(s) and physical and chemical properties ................................... 100 B.1.1. Name and other identifiers of the substance(s) ..................................................... 100 B.1.2. Composition of the substance(s) ....................................................................... 100 B.1.3. Physicochemical properties ............................................................................. 101 B.1.4. Justification for grouping ................................................................................ 108 B.2. Manufacture and uses (summary) ........................................................................... 108 B.3. Classification and labelling ..................................................................................... 108 B.3.1. Classification and labelling in Annex VI of Regulation (EC) No 1272/2008 (CLP Regulation) ........................................................................................................................ 108 B.3.2. Classification and labelling in classification and labelling inventory/ Industry’s self- classification(s) and labelling .................................................................................... 108 B.4. Environmental fate properties ................................................................................ 110 B.4.1. Degradation ................................................................................................ 110 B.4.2. Environmental distribution .............................................................................. 117 B.4.3. Bioaccumulation ........................................................................................... 118 B.4.4. Secondary poisoning ..................................................................................... 118 B.5. Human health hazard assessment ........................................................................... 118 B.6. Human health hazard assessment of physicochemical properties ..................................... 118 B.7. Environmental hazard assessment ........................................................................... 118 B.7.1. Aquatic compartment (including sediment) .......................................................... 118 B.7.2. Terrestrial compartment ................................................................................. 128 B.7.3. Atmospheric compartment .............................................................................. 139 B.7.4. Microbiological activity in sewage treatment systems ............................................. 139 B.7.5. Non compartment specific effects relevant for the food chain (secondary poisoning) ...... 139 P.O. Box 400, FI-00121 Helsinki, Finland | Tel. +358 9 686180 | echa.europa.eu BACKGROUND DOCUMENT TO THE RESTRICTION REPORT ON CALCIUM CYANAMIDE B.8. PBT and vPvB assessment ..................................................................................... 139 B.9. Exposure assessment ........................................................................................... 139 B.9.1. General discussion on releases and exposure ....................................................... 139 B.9.2. Manufacturing ............................................................................................. 140 B.9.3. Use 1: Use of calcium cyanamide as a fertiliser .................................................... 140 B.9.4. Other sources .............................................................................................. 152 B.9.5. Overall environmental exposure assessment ........................................................ 152 B.9.6. Combined human exposure assessment1 ...........................................................
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