LINEAR ALKYLBENZENE SULFONATE (LAS) - UNEP Chemicals

OECD SIDS LINEAR ALKYLBENZENE SULFONATE (LAS)
10) earthworms were added to closed containers with perforated lids for
ventilation. Approximately 5 g per worm were added after the test animals
had been introduced. The containers were then incubated for 21 days in
darkness and the contents were later wet sieved through a 1-mm mesh.
Water content was adjusted after 14 days.
For the growth test with juvenile A. caliginosa (2-3 weeks old), 60 g dry
weight of soil were mixed with 9.6 mL of LAS solution with a spatula and
filled into 160-mL polyethylene beakers with perforated lids for ventilation.
The six treatments consisted of one control and five concentrations of LAS
and these treatments were randomly assigned to the experimental units. After
24-hour equilibration of the test soil, one earthworm was added to each
container. The beakers were incubated for 28 days in darkness and then the
earthworms were recovered and their guts were cleared. The surviving
animals were dried for 24 hours and their dry weight was recorded to the
nearest 0.1 mg. The examination of the effects on growth of A. longa used
the same method except the test period was 42 days.
Enchytraeid test:
The enchytraeid reproduction test followed a previously described protocol
(draft ISO/WD 16387) using the potworm (Enchytraeus albidus). Forty
grams dry weight of soil were mixed with 6.4 mL of LAS solution and filled
into 160-mL beakers with perforated lids for ventilation. After 24-hour
equilibration of the test soil, 10 adult E. albidus were added to each container
and incubated in darkness for 21 days. After incubation, the surviving adult
animals were removed from the soil. Now only containing cocoons, the soil
was incubated in the beakers for another 21 days to allow development and
hatching of the juveniles. After this period, the soil containing juveniles was
stained with Bengal red, and water was added to facilitate counting of the
juveniles. The test concentrations were not provided but can be estimated
from Figure 5 to be 0, 20, 40, 80, 200 and 400 mg/kg with the numbers of
adults surviving per replicate to be approximately 10, 10, 10, 10, 9, and 6,
and the numbers of juveniles per replicate (reproduction) to be approximately
77, 50, 37, 21, 0, and 0, respectively.
Springtail tests:
No internationally accepted guideline is available for springtail reproduction.
Effects of reproduction of F. fimetaria were determined using a method
described by Wiles and Krogh. Twenty-seven grams dry weight of soil were
mixed with 3 mL of LAS solution and filled into cylindrical test containers
with lids. The bottom of the cylinder consisting of a 1-mm mesh to allow
later extraction of the test animals. The mesh was covered with a layer of
plastic film to prevent escape of the test animals. Adult, rather than juvenile,
springtails were used. Ten male and ten female F. fimetaria (23-26 days old)
were added to the test containers after 24-hour equilibration of the test soil.
The containers were incubated for 21 days with 12:12 photoperiod (h). after
incubation, the animals were extracted using MacFadyen high-gradient
extraction and the number of offspring counted. The same procedure was
used for the springtail species H. assimilis Krausbauer, using ten male and
ten female adults (16-19 days old). The test concentrations were not listed
but can be estimated from Figure 6 to be 0, 10, 25, 75, 275, and 800, with the
numbers of adult surviving per replicate to be approximately 145, 155, 115,
110, 165, and 165 and the numbers of juveniles per replicate (reproduction)
to be approximately 285, 275, 190, 145, 205, and 10.
Predacious mite test:
No internationally accepted guideline is available for mite reproduction.
Effects on reproduction on the predacious mite (H. aculeifer) were examined
according to a method described by Krogh and Axelsen. A total of 54 g dry
weight of soil was mixed with 6 mL of LAS solution and filled into test
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