Registration Dossier
Registration Dossier
Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.
The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.
Use of this information is subject to copyright laws and may require the permission of the owner of the information, as described in the ECHA Legal Notice.
EC number: 231-970-5 | CAS number: 7782-91-4
Long-term toxicity to aquatic invertebrates
Administrative data
Link to relevant study record(s)
Description of key information
Relevant and reliable data for the freshwater environment were retrieved for 4 different species: the rotifer Brachionus calyciflorus, the cladocerans Daphnia magna and Ceriodaphnia dubia, and the midge Chironomus riparius. Test results were obtained in experiments that followed international accepted guidance, and were based on measured levels of dissolved molybdenum. Values were 193.6 mg/L, 89.5 mg/L, 63.0 mg/L and 121.4 mg/L, respectively.
Relevant and reliable data for the marine environment were retrieved for 2 different species: the copepod Acartia tonsa and the mysid Americamysis bahia. Test results were obtained in experiments that followed international accepted guidance, and were based on measured levels of dissolved molybdenum. Values were EC10 = 7.96 mg/L and NOEC = 116 mg/L, respectively.
Key value for chemical safety assessment
Additional information
Freshwater compartment
For the rotifer Brachionus calyciflorus the 48h-EC10 value of 193.6 mg/L is retained for the derivation of a predicted no-effect concentration for molybdenum (De Schamphelaere et al, 2008). EC10 values are preferred over NOEC values as the latter are test design-dependent values. In this specific case the 48h-EC10 is even more sensitive than the 48h-NOEC of 244 mg/L.
For Ceriodaphnia dubia two reliable studies were identified: GEI (2009) and De Schamphelaere et al (2008). K1-values were available for two endpoints, with reproduction being more sensitive than survival. T
For the midge Chironomus riparius the 14d-EC10 value is 121.4 mg/L (De Schamphelaere et al, 2008). EC10 values are preferred over NOEC values as the latter are test design-dependent values. In this specific case the 14d-EC10 is more sensitive than the 14d-NOEC of 393 mg/L.
For the cladoceran Daphnia magna there were three studies that provided K1 effects data: GEI (2009), Rodriguez (2007) and De Schamphelaere et al (2008a). Each of these studies reported 21d-EC10 values based on reproduction.
Marine compartment
A reliable 20d-EC10 of 7.96 mg Mo/L has been generated for the marine copepod Acartia tonsa (Aquasense, 2009). EC10 values are preferred over NOEC values as the latter are test design-dependent values. In this specific case the 20d-EC10 is markedly lower than the 20d-NOEC of 26 mg Mo/L.
A chronic 28d-growth and reproduction test has been conducted with the marine mysid shrimp Americamysis bahia (Lehman, 2010). No significant effects were noted at the highest exposure concentration level of 116 mg Mo/L (mean measured value). Evaluated endpoints were survival (first and second generation), reproduction (time of first brood, interbrood time, number of young produced per female), and growth (length and dry weight of male and female adult first generation organims). The unbounded value of 116 mg Mo/L is considered as a reliable and conservative NOEC-value for A. bahia.
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.
Reproduction or further distribution of this information may be subject to copyright protection. Use of the information without obtaining the permission from the owner(s) of the respective information might violate the rights of the owner.
