Captan

Toxicity to terrestrial arthropods

Link to relevant study record(s)

Reference

Endpoint:

toxicity to terrestrial arthropods: short-term

Type of information:

experimental study

Adequacy of study:

key study

Study period:

19 July to 3 August 1990

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

comparable to guideline study

Remarks:

GLP - Guideline study The experiments were done according to the UK MAFF PSPS Working Document D3 (1979).

Qualifier:

according to guideline

Guideline:

other: UK MAFF PSPS Working Document D3 (1979)

Deviations:

no

Qualifier:

equivalent or similar to guideline

Guideline:

EU Method C.16 (Honeybees - Acute Oral Toxicity Test)

GLP compliance:

yes

Application method:

other: contact and oral

Analytical monitoring:

no

Vehicle:

yes

Remarks:

acetone

Test organisms (species):

Apis mellifera

Animal group:

Hymenoptera (honeybees)

Study type:

laboratory study

Limit test:

yes

Total exposure duration:

48 h

Test temperature:

22.5 - 24° C

Humidity:

56 - 68% relative humidity

Key result

Duration:

24 h

Dose descriptor:

LD50

Effect conc.:

> 100 µg per animal

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks:

oral

Remarks on result:

other: 0.154 - 0.218 % CL

Key result

Duration:

48 h

Dose descriptor:

LD50

Effect conc.:

> 100 µg per animal

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks:

oral

Remarks on result:

other: 0.142 - 0.206 % CL

Key result

Duration:

24 h

Dose descriptor:

other: NOEL

Effect conc.:

>= 100 µg per animal

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks:

oral

Key result

Duration:

48 h

Dose descriptor:

other: NOEL

Effect conc.:

>= 100 µg per animal

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks:

oral

Key result

Duration:

24 h

Dose descriptor:

LD50

Effect conc.:

> 200 µg per animal

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks:

contact

Remarks on result:

other: 0.166 - 0.215 % CL

Key result

Duration:

48 h

Dose descriptor:

LD50

Effect conc.:

> 200 µg per animal

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks:

contact

Remarks on result:

other: 0.150 - 0.199 % CL

Key result

Duration:

24 h

Dose descriptor:

other: NOEL

Effect conc.:

>= 200 µg per animal

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks:

contact

Key result

Duration:

48 h

Dose descriptor:

other: NOEL

Effect conc.:

>= 200 µg per animal

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks:

contact

Contact Tests

The 20 µg bee^-1dose level of the formulation required the application of two 1 µL drops. Therefore this treatment was not strictly comparable with the others which received 1 µL. Consequently, it was excluded from the statistical analysis. This had no effect on the conclusions reached as to the LD50 value or the NOEL because of the total lack of observed effects on bees in this treatment.

There was no mortality attributable to technical captan so that the 24- hour LD50s were greater than the highest dose tested: 200 and 20 µg bee^-1, respectively. The 48- hour results were similar.

There were no treatment related sublethal effects observed in bees treated with technical captan. Using the combined mortality and sub-lethal effects values, the NOELs were therefore equal to or greater than the highest dose tested (200 and 20 µg bee^-1, respectively).

Oral Tests

There was no mortality or sublethal effects attributable to either technical Captan. Therefore, the 24- and 48- hour LD50 values were greater than and the NOELs equal to or greater than the highest doses tested: 100 µg bee^-1for technical captan.

Overall there were no treatment-related mortalities or sublethal effects of captan in the oral or contact

tests at any dose at any assessment time. Mortality following treatment with dimethoate occurred at expected levels.

Validity criteria fulfilled:

not specified

Conclusions:

The 24 and 48-hour oral LD50 of captan to the honey bee is higher than 100 µg captan/bee. The 24 and 48-hour contact LD50 of captan to the honey bee is higher than 200 µg captan/bee.

Executive summary:

Laboratory tests was carried out on captan technical. There were two tests for each route of administration for technical captan: a rangefinder test and a definitive test based on the results of the rangefinder test.

The 24 hour contact LD50 values for technical captan was >200 and >20 µg bee^-1, respectively. The 24-hour oral LD50 values for technical captan was >100 and >20 µg bee^-1. The No Observed Effect Levels (NOELs) were greater than, or equal to, the highest dose tested in each case. Results obtained for dimethoate tested concurrently as a toxic standard indicated that the bees were reacting normally under the test conditions

Description of key information

Toxicity to terrestrial arthropods: LD50 (oral, 24h and 48h) >100 µg captan/bee, LD50 (contact, 24h and 48h) >200 µg captan/bee for worker Honey bees (Apis mellifera), Guideline UK MAFF PSPS Working Document D3 (1979).

Toxicity to terrestrial arthropods: LD50 (oral, 24h and 48h) >100 µg captan/bee, 


        
  

LD50 (contact, 24h and 48h) >200 µg captan/bee for worker Honey bees (Apis mellifera), Guideline UK MAFF PSPS Working Document D3 (1979).

Additional information

The result show that the 24-hour contact LD50 values for technical captan was >200 and >20 µg bee^-1, respectively. These results indicate that the technical material is 'virtually non-toxic' to bees in the laboratory under the conditions of these tests (using the classification of the International Commission for Bee Botany-Second Symposium on harmonisation of methods for testing the toxicity of pesticides to bees, Hohenheim, West Germany, 21-23 September 1982). There were no treatment effects at the doses tested there is no evidence of any difference in the level of safety. There were no treatment related sublethal effects for the technical material so that the NOEL were ≥200 and ≥20 µg ai bee^-1,respectively. There were no significant changes in the results in either the contact or the oral tests after 48 hours compared with 24 hours indicating that there were no delayed effects.