Captan

Toxicity to soil macroorganisms except arthropods

Link to relevant study record(s)

Reference

Endpoint:

toxicity to soil macroorganisms except arthropods: short-term

Type of information:

experimental study

Adequacy of study:

key study

Study period:

11 April to 25 April 1985

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 207 (Earthworm, Acute Toxicity Tests)

Version / remarks:

1984

Deviations:

no

GLP compliance:

no

Specific details on test material used for the study:

- Physical state: white powder
- Purity: 90.5 %
- Batch number: 27878/611522
- Date of arrival: 30 January 1985

Analytical monitoring:

no

Vehicle:

yes

Details on preparation and application of test substrate:

Artificials soil: 69% industrial quartz sand, 20% kaolin clay, 10% sphagnum peat, 1% calcium carbonate, pH = 6.5

Test organisms (species):

Eisenia fetida

Animal group:

annelids

Study type:

laboratory study

Substrate type:

artificial soil

Limit test:

yes

Total exposure duration:

14 d

Test temperature:

17 - 22° C

pH:

6.5

Nominal and measured concentrations:

nominal concentrations in soil: 5.2, 15.6, 52.0, 155.9, 519.3 ppm/active ingredient

Reference substance (positive control):

yes

Remarks:

chloroacetamide

Key result

Duration:

14 d

Dose descriptor:

LC50

Effect conc.:

> 519.3 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Results with reference substance (positive control):

LC50(7d) = 35.8 mg/Kg; LC50(14d) = 20.8 mg/Kg

Chloroacetamide at a concentration of 3.0 to 243.0 mg/kg led to 27.5 - 100% mortality after 14 days. Mortality with captan is summarised in Table 6.3.1 -1.

Table 6.3.1-1 Summary of effects of captan on earthworms after 14 days exposure

Captan concentration (mg/kg)^1	% Mortality
	7 days	14 days
0	0	0
5.2	0	7.5
15.6	5.0	10.0
52.0	5.0	20.00
155.9	10.0	37.5
519.3	7.5	32.5

¹Nominal concentrations

Validity criteria fulfilled:

yes

Remarks:

Validity criteria of OECD Method 207 (1984) been fulfilled: The mortality in the controls does not exceed 10 per cent at the end of either test

Conclusions:

The 14-day LC50 of technical captan to earthworms was determined to be higher than 519.3 mg/kg.

Executive summary:

Test compound: Captan technical

 Protocol: OECD guidelines (1984) for testing of chemicals, entitled "Earthworm, Acute Toxicity Tests".

Test species: Earthworm, Eisenia foetida.

Duration of treatment: A Single soil treatment followed by a 14-day exposure period.

Treatments: Treatments included a negative control group and five groups treated with test compound at levels ranging from 5.2 mg/kg to 519.3 mg/kg .

Because of the limited number of mortalities in the test groups, it was not possible to determine LC50 values for Captan at 7 and 14 days. These values must lie in excess of the maximum dose level of 519.3 mg/kg.

The LC50 values for control group (chloroacetamide) were as follows:

 

Day 7:

LC50 value (ppm ai) 35.9 (95% confidence limits 20.6 – 68.9 ppm ai)

Day 14:

LC50 value (ppm ai) 20.8 (95% confidence limits 9.5 – 47.8 ppm ai)

 

The results indicate that Captan technical is of low toxicity to earthworms at concentrations of 5.2 to 519.3 mg/kg in soil.

Description of key information

Toxicity to soil macroorganisms except arthropods (Eisenia foetida): LC50 (14 day) >519,3 mg/kg for earthworms (Eisenia foetida), OECD Guideline No. 207 (1984) "Earthworm acute toxicity test"

Key value for chemical safety assessment

Short-term EC50 or LC50 for soil macroorganisms:

519.3 mg/kg soil dw

Additional information

The results indicate that captan is of low toxicity to earthworms at concentrations of 5.2 to 519.3 mg/Kg in soil. LC50 was not reached.