Propargite

Toxicity to soil macroorganisms except arthropods

Link to relevant study record(s)

Reference

Endpoint:

toxicity to soil macroorganisms except arthropods: long-term

Type of information:

experimental study

Adequacy of study:

key study

Study period:

20th December 2000 to 6th February 2001

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 207 (Earthworm, Acute Toxicity Tests)

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

no

Vehicle:

yes

Details on preparation and application of test substrate:

- Method of mixing into soil (if used): appropriate amounts of test material were weighed into glass beakers and 40 mL acetone added and the test material allowed to dissolve. These solutions were then poured over separate 100 g dry weight of soil substrate. After all the acetone had evaporated, the treated 100 g was added to the remaining soil substrate and the two amounts of substrate well-mixed. The deionised water required for moisturisation was then added to the substrate and well mixed before being transferred back to the test vessels.
- Controls: control and solvent control
- Chemical name of vehicle (organic solvent, emulsifier or dispersant): acetone
- Evaporation of vehicle before use: yes

Test organisms (species):

Eisenia fetida

Animal group:

annelids

Details on test organisms:

TEST ORGANISM
- Common name: earthworm
- Age at test initiation (mean and range, SD): 4-5 months (preliminary test); 5.5-6.5 months (definitive test)

ACCLIMATION
- Acclimation period: 2 days (preliminary test); 1-4 days (definitive test)

Study type:

laboratory study

Substrate type:

artificial soil

Limit test:

no

Total exposure duration:

14 d

Test temperature:

18.7-20.5 ºC (soil); 20-21.5 ºC (air)

pH:

5.51-5.70

Moisture:

Initial moisture content of 36.8 and 39.5 % w/w for the preliminary and definitive tests, respectively. 5.9 % of the initial content lost over the duration of the test.

Details on test conditions:

TEST SYSTEM
- Test container (material, size): 1000 mL glass beakers covered with a polyethylene adhesive film and perforated with a single hole.
- Amount of soil or substrate: 555.5 g
- No. of organisms per container (treatment): 10
- No. of replicates per treatment group: 1 (preliminary), 4 (definitive)
- No. of replicates per control: 1 (preliminary), 4 (definitive)
- No. of replicates per vehicle control: 1 (preliminary), 4 (definitive)

SOURCE AND PROPERTIES OF SUBSTRATE (if soil)
- Composition (if artificial substrate): 10 % w/w sphagnum moss, 20 % w/w kaolin clay, 70 % w/w industrial sand (50 % of particles between 50 and 200 µm)
- Pretreatment of soil: pH adjusted to 5.5 to 6.5 by the addition of calcium carbonate

OTHER TEST CONDITIONS
- Photoperiod: continuous illumination
- Light intensity: 379-532 lux

VEHICLE CONTROL PERFORMED: yes

TEST CONCENTRATIONS
- Range finding study
- Test concentrations: 10, 30, 100, 300, 1000, 3000 and 10,000 mg/kg dry soil (target); 14.1, 31.8, 102, 302, 998, 3000 and 10,000 mg/kg dry soil (calculated)
- Results used to determine the conditions for the definitive study: yes

Nominal and measured concentrations:

56, 100, 180, 320, 560 and 1000 mg/kg dry soil (target)

56.2, 99.7, 180, 321, 560 and 999 mg/kg dry soil (calculated)

Reference substance (positive control):

no

Key result

Duration:

7 d

Dose descriptor:

LC50

Effect conc.:

760 mg/kg soil dw

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: 95 % C.I. 676-681 mg/kg dw

Key result

Duration:

14 d

Dose descriptor:

LC50

Effect conc.:

387 mg/kg soil dw

Conc. based on:

test mat.

Basis for effect:

mortality

Remarks on result:

other: 95 % C.I. 341-419 mg/kg dw

Key result

Duration:

14 d

Dose descriptor:

NOEC

Effect conc.:

180 mg/kg soil dw

Conc. based on:

test mat.

Basis for effect:

mortality

Key result

Duration:

14 d

Dose descriptor:

LOEC

Effect conc.:

321 mg/kg soil dw

Conc. based on:

test mat.

Basis for effect:

mortality

Key result

Duration:

14 d

Dose descriptor:

NOEC

Effect conc.:

< 56.2 mg/kg soil dw

Conc. based on:

test mat.

Basis for effect:

other: weight loss

Key result

Duration:

14 d

Dose descriptor:

LOEC

Effect conc.:

56.2 mg/kg soil dw

Conc. based on:

test mat.

Basis for effect:

other: weight loss

Details on results:

There were no mortalities at days 7 or 14 in either the control, solvent control or 56.2, 99.7 and 180 mg/kg dry soil test concentrations. There were also no mortalities after 7 days at 321 mg/kg dry soil although by 14 days, mortality in this group was 25 %. Mortality in the 560 mg/kg dry soil group was 27.5 and 100 % after days 7 and 14, respectively. Mortality in the 999 mg/kg dry soil group was 72.5 and 100 % after days 7 and 14, respectively.

Based on weight measurements at the start and end of the exposure period, mean percent weight loss was 4.13, 3.03, 15.4, 26.5 and 39.5 in the control, solvent control, 56.2, 99.7, 180 and 321 mg/kg groups, respectively. Weight loss determinations were not possible for the two highest test concentrations because of 100 % mortality.

Behavioural/sublethal effects included lethargy, moribundity, emaciation and shrivelled/shrunken appearance. There were no sublethal effects at 56.2 mg/kg dw soil.

Reported statistics and error estimates:

The 7 and 14 day LC50s were calculated by probit analysis and trimmed Spearman-Karber, respectively. The NOEC and LOEC values form mortality were calculated using Steel's Many-One Rank test. Prior to calculating the NOEC and LOEC values for body weight, the data was tested for normality using the Shapiro-Wilks test and for homogeneity of variance using Bartletts test. The body weigh NOEC and LOEC values were then calculated using Dunnett's test.

Table 1: Mortality of worms in the definitive test

	Number of mortalities (day 7/day 14)
Conc. (mg/kg dry soil)	Replicate 1	Replicate 2	Replicate 3	Replicate 4	Percent mortality (day 7/day 14)
Control	0/0	0/0	0/0	0/0	0/0
Solvent control	0/0	0/0	0/0	0/0	0/0
56.2	0/0	0/0	0/0	0/0	0/0
99.7	0/0	0/0	0/0	0/0	0/0
180	0/0	0/0	0/0	0/0	0/0
321	0/2	0/4	0/3	0/1	0/25
560	2/10	2/10	7/10	0/10	27.5/100
999	8/10	9/10	3/10	9/10	72.5/100

Table 2: Mean live weights (g) of worms

Conc. (mg/kg dry soil)	Replicate number	Mean live wt (g) day 0 (start)	Mean live wt (g) day 14 (end)	Percent change	Mean percent change
Control	1	0.341	0.316	-7.33	-4.13
	2	0.385	0.352	-8.57
	3	0.330	0.327	-0.909
	4	0.343	0.344	+0.292
Solvent control	1	0.385	0.372	-3.38	-3.03
	2	0.357	0.336	-5.88
	3	0.395	0.380	-3.80
	4	0.322	0.325	+0.932
56.2	1	0.350	0.296	-15.4	-15.4
	2	0.358	0.316	-11.7
	3	0.394	0.320	-18.8
	4	0.381	0.321	-15.7
99.7	1	0.336	0.271	-19.3	-15.4
	2	0.388	0.324	-16.5
	3	0.356	0.300	-15.7
	4	0.356	0.321	-9.83
180	1	0.339	0.231	-31.9	-26.5
	2	0.333	0.250	-24.9
	3	0.379	0.283	-25.3
	4	0.363	0.277	-23.7
321	1	0.357	0.214	-40.1	-39.5
	2	0.362	0.234	-35.1
	3	0.324	0.177	-45.3
	4	0.406	0.253	-37.6
560	1	0.343	-	-	-
	2	0.370	-	-
	3	0.328	-	-
	4	0.395	-	-
999	1	0.319	-	-
	2	0.368	-	-
	3	0.324	-	-
	4	0.356	-	-

Table 3: Sublethal effects

Conc. (mg/kg dry soil)	Observations made on day 7	Observations made on day 14
Control	N/S	N/S/
Solvent control	N/S	N/S
56.2	N/S	N/S
99.7	N/S	8 % LT
180	N/S	20 % EM
321	3 % SA	70 % EM, 70 % LT, 40 % MO
560	35 % SA, 93 % LT, 14 % MO	-
999	36 % SA, 91 % LT, 9 % MO	-

- = 100% mortality

NS = none seen

EM = emaciated, similar in length to controls but with a thin appearance

SA = shrivelled/shrunken appearance, similar to emaciated but with a distinctly ridged surface to the skin

LT = lethargic movements, reduced activity when compared to the controls

MO = moribund, extremely slow to respond to stimulation, very little movement

Validity criteria fulfilled:

yes

Conclusions:

Under the conditions of the test, 7 and 14 day LC50 values of 760 and 378 mg/kg dry soil were determined for the earthworm, Eisenia foetida, following exposure to propargite in artificial soil. 14 day NOEC and LOEC values based on mortality were 180 and 321 mg/kg dry soil, respectively. NOEC and LOEC values based on body weight loss were <56.2 and 56.2 mg/kg dry soil, respectively.

Executive summary:

A 14 day acute toxicity study with Eisenia foetida based on OECD Guideline 207 was performed using propargite of 90.2 % w/w purity. Six concentrations of treated soil were tested (56.2, 99.7, 180, 321, 560 and 999 mg/kg dry soil) plus a control and solvent control. Each treatment was replicated four times.

The following results were obtained:

Endpoint	Test	Result (mg/kg dry soil)
Mortality after 7 or 14 days of exposure	Preliminary
	14 day LC50	269 (95 % C.I. 175 to 415)
	Definitive
	7 day LC50	760 (95 % C.I. 676 to 871)
	14 day LC50	378 (95 % C.I. 341 to 419)
	14 day NOEC	180
	14 day LOEC	321
Percent change in live weight of worms over 14 days exposure	Definitive
	NOEC	<56.2
	LOEC	56.2

Description of key information

7 d EC50 760 mg/kg soil dw, 14 d NOEC (body weight loss) <52 mg/kg dw soil; study conducted in accordance with OECD Guideline 207; Hayward, 2001

Key value for chemical safety assessment

Short-term EC50 or LC50 for soil macroorganisms:

760 mg/kg soil dw

Additional information

A 14 day acute toxicity study with Eisenia foetida based on OECD Guideline 207 was performed using propargite of 90.2 % w/w purity. Six concentrations of treated soil were tested (56.2, 99.7, 180, 321, 560 and 999 mg/kg dry soil) plus a control and solvent control. Each treatment was replicated four times.

The following results were obtained:

Endpoint	Test	Result (mg/kg dry soil)
Mortality after 7 or 14 days of exposure	Preliminary
	14 day LC50	269 (95 % C.I. 175 to 415)
	Definitive
	7 day LC50	760 (95 % C.I. 676 to 871)
	14 day LC50	378 (95 % C.I. 341 to 419)
	14 day NOEC	180
	14 day LOEC	321
Percent change in live weight of worms over 14 days exposure	Definitive
	NOEC	<56.2
	LOEC	56.2