Propargite

Long-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1st December 1983 to 22nd December 1983

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Qualifier:

according to guideline

Guideline:

other: ASTM (1981) E-47.01 and US EPA (1975) EPA_660/3-75-009

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

Exposure concentrations of Omite were measured analytically on days 0, 4, 7, 14 and 21. The mean measured exposure levels were determined by gas chromatography.

Vehicle:

yes

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Chemical name of vehicle (organic solvent, emulsifier or dispersant): acetone

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: water flea
- Source: Analytical Biochemistry Laboratories, Inc., Columbia, MO 65205, USA
- Age of parental stock (mean and range, SD): <24 hours old
- Feeding during test: yes
- Food type: an algal (Selenastrum capricornutum) suspension and a trout chow suspension
- Amount: 20-30 mL of the algal suspension and 5 mL of the trout chow suspension
- Frequency: three times daily for the algal suspension and once daily for the trout chow suspension

Test type:

flow-through

Water media type:

freshwater

Limit test:

no

Total exposure duration:

21 d

Test temperature:

20-21 ºC

pH:

8.1-8.4

Dissolved oxygen:

7.5-9.4 mg/L

Nominal and measured concentrations:

0, 3.3, 6.0, 12, 22 and 50 µg/L (nominal)

0, 2.5, 4.1, 9.0, 14 and 38 µg/L (measured)

Details on test conditions:

TEST SYSTEM
- Test vessel: 1 L test beakers
- Type (delete if not applicable): open (with stainless steel mesh)
- Type of flow-through: proportional diluter
- Renewal rate of test solution (frequency/flow rate): 4 times in a 24 hour period
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4
- No. of vessels per vehicle control (replicates): 4

TEST MEDIUM / WATER PARAMETERS
- Metals: up to 0.056 ppm
- Alkalinity: 368 ppm
- Conductivity: 500 µmhos/cm

EFFECT PARAMETERS MEASURED (with observation intervals if applicable):
- Number of young three times a week; adult length at termination of study.

VEHICLE CONTROL PERFORMED: yes

Reference substance (positive control):

no

Key result

Duration:

21 d

Dose descriptor:

other: MATC

Effect conc.:

> 9 - < 14 µg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

mortality

Details on results:

- Mortality of parent animals: survival from 38 µg/L was significantly different from the controls
- No. of offspring produced per day per female: 6.1-6.4
- Body length and weight of parent animals: Daphnid lengths from 14 µg/L were significantly different from the controls; length analysis from 38 µg/L could not be performed since no adults survived to 21 days

Reported statistics and error estimates:

Statistical analysis
Adult length (pooled), survival and total young/adult/reproduction day were subjected to one way analysis of variance. When treatment effects were indicated following a significant F-test of the mean square ratios, a multiple means comparison test, Fisher's protected Least Significant Difference test (LSD) was used to determine which exposure levels differed from the controls.

Percent survival data were transformed for analysis using the following equation:
Angle = 2 arcsin √(X/N)

where:
X = number of organisms started with
N = number of organisms surviving to day 21

Total young/adult/reproduction day for each replicate was calculated as:
Total number of young produced / Total number of adult reproduction days

Table 1: Percent survival, young/adult/reproduction day and adult length

Concentration (µg/L)		Adult mean length (mm)	Mean percent survival	Mean young/adult/reproduction day
Control		3.5 ± 0.13	82 ± 15	6.2 ± 0.55
Solvent control		3.5 ± 0.12	95 ± 10	6.5 ± 0.31
2.5		3.5 ± 0.13	92 ± 9.6	6.4 ± 0.32
4.1		3.5 ± 0.13	85 ± 17	6.1 ± 0.60
9.0		3.5 ± 0.16	95 ± 5.8	6.4 ± 0.49
14		3.4 ± 0.13	95 ± 5.8	6.3 ± 0.28
38		*	0	0

*no adult survivors

Validity criteria fulfilled:

not specified

Conclusions:

Under the conditions of the test, propargite had no effect on survival or reproduction at concentrations up to 14 µg/L. However, this concentration caused a significant reduction in adult length. There was no effect on adult length at concentrations up to 9 µg/L. Therefore the NOEC, LOEC and MATC values were estimated to be 9, 14 and 9-14 µg/L, respectively.

Executive summary:

A 21 day life cycle toxicity study of Omite^® to Daphnia magna was conducted to determine the Maximum Acceptable Toxicant Concentration limits. A 0.5 L proportional diluter system was used to maintain constant test concentrations. Exposure concentrations of Omite^® were measured analytically on days 0, 4, 7, 14 and 21. The mean measured concentrations determined by GC were 2.5, 4.1, 9.0, 14 and 38 µg/L. The mean measured exposure levels remained consistent throughout the study and all results were based on these values.

The daphnid lengths at 14 µg/L were significantly different from the control. Length analysis of the 38 µg/L concentration could not be performed since no adults survived after 21 days. Statistical analysis of survival indicated that 38 µg/L was significantly different from the control. The mean young/adult/reproduction day was significantly affected at 38 µg/L.

Based on the statistical analysis of adult mean length, survival and young/adult/reproduction day, the MATC limits were estimated to be 9 and 14 µg/L.

Description of key information

MATC 9-14 µg/L; study conducted in accordance with ASTM (1981) E-47.01 and US EPA (1975) EPA_660/3-75-009; Forbis and Frankin, 1984

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

9 µg/L

Additional information

A 21 day life cycle toxicity study of propargite to Daphnia magna was conducted to determine the Maximum Acceptable Toxicant Concentration limits. A 0.5 L proportional diluter system was used to maintain constant test concentrations. Exposure concentrations of propargite were measured analytically on days 0, 4, 7, 14 and 21 and mean measured concentrations determined to be 2.5, 4.1, 9.0, 14 and 38 µg/L. The mean measured exposure levels remained consistent throughout the study and all results were based on these values.

The daphnid lengths at 14 µg/L were significantly different from the control. Length analysis of the 38 µg/L concentration could not be performed since no adults survived after 21 days. Statistical analysis of survival indicated that 38 µg/L was significantly different from the control. The mean young/adult/reproduction day was significantly affected at 38 µg/L. Based on the statistical analysis of adult mean length, survival and young/adult/reproduction day, the MATC limits were estimated to be 9 and 14 µg/L.