The product from the burning of a combination of carbonaceous materials.

Toxicity to terrestrial arthropods

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

toxicity to non-target arthropods on natural substrate (NTA other than pollinators)

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

no data

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Non-GLP compliant, non-guideline experimental study. Study published in a scientific, peer reviewed journal.

Reason / purpose for cross-reference:

reference to same study

Qualifier:

no guideline available

Principles of method if other than guideline:

A laboratory study using microcosms.Each ash treated microcosm received 2,8 g wood ash corresponding to 5000 kg wood ash per hectare. Microarthropods were later reintroduced into the systems.

GLP compliance:

no

Application method:

soil

Details on sampling:

First sampling 15 weeks after the start of the experiment, second sampling week 17, third sampling week 27, fourth sampling week 54. At each sampling five replicates per treatment were taken. Microarthropods were extracted from approximately 10 g f.m. soil sample using a modified high-gradient extractor.

Details on preparation and application of test substrate:

Humus was collected from a pine forest near the city of Jyväskylä, central Finland, sieved through a 1-cm sieve and autoclaved. After sieving soil pH was 4,2, water content 58 % of fresh mass and loss on ignition 48 %. Because the acidity of the soil increased during autoclaving (pH 3,7), 1,0 g CaCO3 to 1 kg fresh mass soil was added, raising the pH to 4,7. Then the soil was stored in plastic bags for 1 month at room temperature. Litter materials (pH 5,8, water content 46 %, LOI 91 %) consisting on birch leaves, spruce and pine needles, were cut into pieces, mixed in equal proportions and defaunated by heating (+60 ◦C for 24 h). Half of the material was treated with wood ash which was carefully mixed into the soil and litter, and the other part was left as ash free controls. Each ash treated microcosm received 2,8 g wood ash corresponding to 5000 kg wood ash per hectare. Microarthropods were later reintroduced into the systems.

Test organisms (species):

other: no data on species

Animal group:

other: mites and collembolas

Study type:

laboratory study

Total exposure duration:

54 wk

Test temperature:

Incubation conditions were set up to simulate summer (+17°C), autumn (day +7°C, night + 5°C), winter (+2,5-+4°C) and spring (day +7°C, night +5°C).

Photoperiod and lighting:

summer daily cycle of 16 h light, illumination 350 µmol/m2/s, autumn daily cycle of 10 light, winter 5 h of light, spring 10 h light

Reference substance (positive control):

no

Duration:

54 wk

Remarks on result:

not measured/tested

Remarks:

Biomass of microarthropods was the endpoint used in the study. No LC-, EC-, NOEC or LOEC values were determined.

Details on results:

Wood ash had a negative effect on the biomass of microarthropods.

Reported statistics and error estimates:

- Wood ash had a negative effect on the biomass of microarthropods (F=16.84, P<0.001)

See illustration: Biomass of microarthropods before (thebaseline sampling) and immediately after the drought (theresistance sampling), and 10 and 37 weeks after the drought (the1st and 2nd resilience samplings) in the ash-free and ash-treated soil (cash-free soil,c+eash-free soil withC. sphagnetorum,aash-treated soil,a+eash-treated soil withC. sphagnetorum,no dist.ash-free soil without drought)

Validity criteria fulfilled:

not specified

Conclusions:

Wood ash had a negative effect on the biomass of microarthropods.

Executive summary:

A non -GLP, non -guideline laboratory microcosm experiment was established using a simulated coniferous forest floor with humus and litter layers, and a seedling of silver birch (Betula pendula). Systems were established with or without wood ash amendment. The biomass of microarthropods was measured. Wood ash had a negative effect on the biomass of microarthropods.

Reference 2

Endpoint:

toxicity to non-target arthropods field studies (NTA other than pollinators)

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

1997-2000

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Non-GLP compliant, non-guideline experimental study. Study published in a scientific, peer reviewed journal.

Reason / purpose for cross-reference:

reference to same study

Qualifier:

no guideline available

Principles of method if other than guideline:

Eight experimental plots, 30 x 30 m2 in size, were established in the study site. Half of the experimental plots received 3000 kg of wood ash / ha and the other half was left as ash-free control plots. Twenty plastic field mesocosms, lysimeters, with a layered structure of mineral soil, humus and litter layers and a seedling of Scots pine (Pinus sylvestris, L.) growing in the systems, were placed on the plots. To allow the entrance of soil fauna, the lysimeters were dug into the ground so that the upper half of the openings on the lysimeter walls were left above the ground.

GLP compliance:

no

Application method:

soil

Details on sampling:

At each sampling two soil samples (each 25 cm2 in area) were taken both from the soil outside the lysimeters and from inside.

Details on preparation and application of test substrate:

The humus and litter materials and the mineral soil used in lysimeters were collected from a pine forest near Jyväskylä, central Finland. The soil materials were gently sieved through 2 cm sieve and defaunated by heating (+51 ◦C for 20 h). After this humus pH was 3,8 and water content 61,3 % of fresh mass, water content of litter and soil were 60,2 and 15,2 % respectively.

Animal group:

other: mites and collembolans

Study type:

semi-field study

Total exposure duration:

152 wk

Remarks:

first sampling at week 40, second sampling at week 58, third sampling at week 95, fourth at week 111 and fifth at week 152.

pH (if soil or dung study):

In ash-free soil pH was 4,1 in June 1998; 3,7 in October 1998; 3,8 in June 1999; 3,7 in October 1999 and July 2000.
In ash-treated soil pH was 4,7 in June 1998; 5,1 in October 1998; 5,2 in June 1999; 4,5 in October 1999 and 4,1 in July 2000.

Duration:

152 wk

Remarks on result:

not measured/tested

Remarks:

Biomass of microarthropods was the endpoint used in the study. No LC-, EC-, NOEC or LOEC values were determined.

Details on results:

Microarthropod biomass was unaffected by the ash treatment.

Microarthropods ( µg/g d.m.soil)

	Ash free soil	Ash treated soil
June 1998	207,7 ± 140,3	171,6 ± 119,2
October 1998	86,6 ± 20,1	119,1 ± 42,5
June 1999	156,4 ± 70,9	71,0 ± 13,4
October 1999	118,3 ± 30,6	83,6 ± 48,3
July 2000	131,9 ± 94,6	145,2 ± 99,4

Validity criteria fulfilled:

not specified

Conclusions:

Microarthropod biomass was unaffected by the ash treatment

Executive summary:

The effects of ash on the biomass of microarthropods were studied in a non -GLP, non-guideline field experiment. Microarthropod biomass was unaffected by the ash treatment.

Description of key information

Toxicity of ash to terrestrial arthropods was estimated based on two scientific publications from literature. Impacts of ash amendments on biomass of microarthropods was studied in microcosm (1st onvestigation) and field (2nd investigation). Ash treatment has been shown to induce a decrease in the biomass of microarthropods (mites and collembolans)  in microcosms laboratory study. However, the effect was not found in a field experiment. There is no data on possible recovery of the populations.