Lead carbonate

Bioaccumulation: terrestrial

Administrative data

Endpoint:

bioaccumulation: terrestrial

Type of information:

experimental study

Adequacy of study:

other information

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Acceptable, well-documented publication which meets basic scientific principles

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

2005

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

Earthworms were exposed to composted cattle manure contaminated with a range of concentration of either lead acetate or lead carbonate.
Relative Pb bioaccumulation rates in earthworms were compared over time (0, 20, 40 and 60 days).

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

Lead carbonate

EC Number:

209-943-4

EC Name:

Lead carbonate

Cas Number:

598-63-0

Molecular formula:

CH2O3.Pb

IUPAC Name:

λ²-lead(2+) carbonate

Details on test material:

- Name of test material (as cited in study report): lead carbonate
- Molecular formula (if other than submission substance): Pb(CO3)2

Radiolabelling:

not specified

Test substrate

Vehicle:

not specified

Test organisms

Test organisms (species):

Lumbricus sp.

Details on test organisms:

TEST ORGANISM
- Common name: Earthworm
- Source: a local bait shop
- Age at test initiation (mean and range, SD): mature
- Weight at test initiation (mean and range, SD): 4-9 g

ACCLIMATION
- Acclimation period: 14 d
- Acclimation conditions: same as test

Study design

Total exposure / uptake duration:

>= 0 - <= 60 d

Total depuration duration:

2 d

Test conditions

Test temperature:

18 °C

Moisture:

20 %

Details on test conditions:

TEST SYSTEM
- No. of organisms per container (treatment): 12
- No. of replicates per treatment group: 4
- No. of replicates percontrol / vehicle control: 4

SOURCE AND PROPERTIES OF SUBSTRATE (if soil)
- % sand: 72.5
- % silt: 21.8
- % clay: 5.7
- pH soil: 7.6
- Organic carbon (%): 1.9

Nominal and measured concentrations:

Nominal: 0, 100, 200 and 500 µg/g
Actual: 5.09, 171, 575 and 710 µg/g

Results and discussion

Any other information on results incl. tables

A significant Pb accumulation by earthworms was observed in the Pb(CO3)2 trial (lower than in PbAc).

The Pb concentration in the earthworm tissue increased with the duration of exposure, and also with the Pb concentration in the organic matter.

Applicant's summary and conclusion

Validity criteria fulfilled:

not specified

Conclusions:

Pb(CO3)2 contamination produces significant Pb bioaccumulation. Yet Pb(CO3)2 may take longer (than PbAc) to equilibrate within the organic matter because of its lower solubility, and thus over time the Pb may become less and less bioavailable, resulting in a non-lihnear Pb bioaccumulation.