Registration Dossier

Ecotoxicological information

Toxicity to aquatic algae and cyanobacteria

Administrative data

Endpoint:
toxicity to aquatic algae and cyanobacteria
Type of information:
experimental study
Adequacy of study:
weight of evidence
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: WHO review by panel of experts
Cross-reference
Reason / purpose:
reference to other study

Data source

Reference
Reference Type:
review article or handbook
Title:
Unnamed
Year:
1989

Materials and methods

Test guideline
Qualifier:
no guideline followed
Principles of method if other than guideline:
The article reviews different publications with lead salts. Different methods with different species were applied.
GLP compliance:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Specific details on test material used for the study:
Details on properties of test surrogate or analogue material (migrated information):
Lead dinitrate is a soluble inorganic lead salt similar to lead acetate. Based on these similarities and the toxic species being the lead cation not the assoicated anions, these data can also be considered as weight of evidence for the other soluble lead salts such as lead acetate

Results and discussion

Effect concentrationsopen allclose all
Duration:
70 d
Dose descriptor:
other: observable toxicity, and growth rates
Effect conc.:
> 0 mol/L
Duration:
14 d
Dose descriptor:
other: visual inspection
Effect conc.:
136 mg/L
Basis for effect:
other: plant kill
Duration:
6 wk
Dose descriptor:
other: root development, leaf colour, development of new plantlets, flowering, or total plant growth
Effect conc.:
> 5 mg/L

Applicant's summary and conclusion

Validity criteria fulfilled:
not applicable
Conclusions:
Both, the available data from public literature (see supporting studies chapter 6.1.5 and 6.1.6) and the hazard identification of lead salts support the decision on a weight of evidence basis that an additional study on toxicity to aquatic algea is scientifically unjustified.
Executive summary:

The WHO assessment (1989) on lead toxicity to aquatic plants comes to the conclusion, that there is little evidence for effects of lead on aquatic plants at concentrations below 1 to 15 mg/litre. Many studies of aquatic plants have been made in sediment-free systems. However, the addition of uncontaminated sediment reduces the toxicity of lead to aquatic plants by reducing its availability.

Both, the available data from public literature (see supporting studies chapter 6.1.5 and 6.1.6) and the hazard identification of lead salts support the decision on a weight of evidence basis that an additional study on toxicity to aquatic algea is scientifically unjustified.