polymeric zinc propylenebis(dithiocarbamate);propineb (ISO)

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:

1990/10/10 to 1990/10/31

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

equivalent or similar to guideline

Guideline:

other: U.S. EPA-FIFRA, 40 CFR, Section 158.145 Guideline 72-4

Version / remarks:

This study was conducted to satisfy the data requirements of U.S. EPA-FIFRA, 40 CFR, Section 158.145, Guideline 72-4.
The biological methodology used for this chronic life cycle study with
daphnids are patterned after procedures formulated by the American Society for Testing and Materials, the U.S. Environmental Protection Agency and the Organization for Economic Cooperation and development
(OECD).

Deviations:

not specified

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

A water sample was added to a 154 mL reaction flask. If necessary, the sample was fortified by adding an appropriate amount of propineb formulation, diluted in 10% of EDTA in boiled deionized water, to the sample flask. Five milliliters of 10% EDTA in boiled deionized water (w/v) were added to the flask, followed by 15 mL of HCl/stannous chloride reagent (8N:3%, w/v). The reaction flask was then quickly capped and sealed. The flask was swirled and placed in a sandbath at 100°C to undergo hydrolysis for 1 hour. After hydrolysis was complete, the reaction flask was transferred to another sandbath at 70°C and allowed to equilibrate for 30 minutes prior to GC analysis. The sample was maintained at 70°C during GC analysis to keep the CS2 formed by hydrolysis in a gaseous state. Working Propineb standards were prepared with each sample set, using the method described above, with the exception that deionized water was used.

Vehicle:

no

Details on test solutions:

The diluter stock solutions were prepared in the following manner: 25 mg of pure, dry Antracol Technical was placed directly on the solenoid valve system. On a timed basis, 400 mL of dilution water flushed the test compound into the mixing chambers which had 100 mL of dilution water already placed inside. The total volume of dilution water was now 500 ml. After stirring for 1 hour in the mixing chamber this solution became the diluter stock solution which had a nominal concentration of 40 mg/L. The diluter system injected a 5.0 mL aliquot of this stock solution into the diluter mixing box (1000 mL).

Test organisms (species):

Daphnia magna

Details on test organisms:

Test specimens of Daphnia magna were obtained from an inhouse daphnid culture. All daphnids were cultured and tested in a temperature controlled area at 20°C (±2). The lighting was provided by cool white fluorescent bulbs at an intensity of 40 - 80 foot candles on a 16-hour daylight and 8-hour darkness photoperiod, with 30 minute dawn and dusk transition periods. During the holding period, the daphnids were fed a suspension of algae (Selenastrum capricornutum and Ankistrodesmus falcatus) supplemented with a trout chow and yeast (Saccharomyces sp.) suspension. Only first-instar daphnids (<24 hours old) were selected for testing.

Test type:

flow-through

Water media type:

freshwater

Remarks:

hard blended water

Limit test:

no

Total exposure duration:

21 d

Hardness:

160-180 mg/L as CaC03 (Hardness)
174 - 220 mg/L (Alkalinity)

Test temperature:

20°C

pH:

8.0 - 8.3

Dissolved oxygen:

8.4 - 8.7 mg/L

Conductivity:

320 - 360 µMhos/cm

Nominal and measured concentrations:

Nominal concentrations: 0.012, 0.024, 0.050, 0.10 and 0.20 mg a.s./L;
Mean measured concentrations: 0.0062, 0.015, 0.028, 0.070 and 0.16 mg a.s./L

Details on test conditions:

Flow-splitting chambers were utilized to thoroughly mix and divide each propineb formulation concentration for delivery to the test chambers. One-liter glass beakers, labeled A, B, C and D, were used as test chambers. These chambers had notched drains which were covered with 50-mesh stainless steel screens to prevent escape of the test daphnids. The test daphnids were placed in each of the quadruplicate chambers. Lighting for the test system was provided by cool white fluorescent bulbs and consisted of a 16-hour daylight, 8-hour darkness and 30-minute dusk and dawn transition periods. Light intensity ranged from 46 - 49 foot candles at the water surface during the conduct of the study.

Reference substance (positive control):

no

Key result

Duration:

21 d

Dose descriptor:

LOEC

Effect conc.:

0.028 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

other: survival, adult mean length, mean time in days to first brood and young/adult/ reproduction

Key result

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

0.015 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

other: survival, adult mean length, mean time in days to first brood and young/adult/ reproduction

Key result

Duration:

21 d

Dose descriptor:

EC50

Effect conc.:

0.026 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

other: mobility

Details on results:

Statistical analysis of survival for Daphnia magna after a 21-day exposure to propineb formulation was found to be significantly effected between the controls and the mean measured concentrations of 0.028, 0.070 and 0.16 mg/L. The control had a mean percent survival of 90.0 ± 14.1 percent. The mean measured concentrations of 0.0062, 0.015, 0.028, 0.070 and 0.16 mg a.s./L had mean percent survivals of 97.5 ± 5.8, 95.0 ± 5.8, 40.0 ± 21.6, 0±0.0 and 0 ± 0.0 percent, respectively. A day 21 EC50 based on immobilization was calculated by the moving average method to be 0.026 mg a.s./L. Immobilization was defined as the absence of movement with gentle prodding.

Adult daphnid length was found to be significantly effected between the control and the mean measured concentration of 0.028 mg a.s./L. The control had a mean daphnid length of 4.08 ±0.22 mm. The mean measured concentrations of 0.0062, 0.015 and 0.028 mg a.s./L had mean daphnid lengths of 4.09 ± 0.15, 3.95 ± 0.20 and 3.57 ± 0.35 mm, respectively. There was 100 percent mortality by day 21 in the mean measured concentrations of 0.070 and 0.16 mg a.s./L so there was no length data available for statistical analysis.

Statistical analysis of time to first brood for Daphnia magna after a 21-day exposure to propineb formulation indicated a no significant difference between the controls and the mean measured concentrations. Time to first brood for both the control was 7 days. The mean test concentrations of 0.0062, 0.015 and 0.028 mg/L took 7 days to first brood. There was no instar production in the mean measured test concentrations of 0.0.070 and 0.16 mg a.s./L, so there was no brood data available for statistical analysis. Young/adult reproduction days were significantly effected when compared with the control at the mean measured concentration of 0.028 mg a.s./L. The control had mean young/adult reproduction days of 4.68 ± 0.33. The mean measured concentrations of 0.0062, 0.015 and 0.028 mg a.s./L had mean young/adult reproduction days of 6.35 ± 0.62, 4.98 ± 0.57 and 1.70 ± 0.38, respectively.

There was no instar production in the mean measured test concentrations of 0.070 and 0.16 mg a.s./L, so no young/adult reproduction days were available for statistical analysis. The averaged total of instar for control and the mean test concentrations 0.0062, 0.015 and 0.028 mg a.s./L were 660, 946, 739, and 217, respectively. All young produced during the study appeared normal. Based on the statistical analysis of survival, adult mean length, mean time in days to first brood and young/adult/ reproduction day from this 21-day Daphnia magna dynamic life cycle study, the MATC limits were estimated to be the measured propineb formulation concentrations of 0.015 and 0.028 mg a.s./L. The point estimate MATC value was calculated to be 0.020 mg a.s./L.

Reported statistics and error estimates:

Survival data was analysed using frequency analysis comparing the test concentration to the control. This analysis was coupled with a one-tailed Fisher's exact test and the chi-square statistic to determine whether the test concentration exhibited a response significantly less than that of the control.
Reproductive data consisted of two parameters indicative of reproductive success. These parameters were: time to first brood and young/adult reproduction days. Total young/adult reproduction day for each replicate.
All statistical analyses were conducted using PC DOS SAS/STAT Release 6.03, with conclusions of statistical significance based on a 95 percent confidence level (P<0.05).

Validity criteria fulfilled:

not specified

Conclusions:

The aim of the study was to investigate the toxicity of propineb to Daphnia magna over 21-day study under flow-through conditions. Daphnids were exposed to nominal concentrations of 0.012, 0.024, 0.050, 0.10 and 0.20 mg a.s./L. Following endpoints were determined and are based on mean measured concentrations:
EC50 (21 day) = 0.026 mg a.s./L
NOEC (21 day) = 0.015 mg a.s./L
LOEC (21 day) = 0.028 mg a.s./L.

Executive summary:

The aim of the study was to investigate the toxicity of propineb to Daphnia magna over 21-day study under flow-through conditions. Daphnids were exposed to nominal concentrations of 0.012, 0.024, 0.050, 0.10 and 0.20 mg a.s./L. Following endpoints were determined and are based on mean measured concentrations:

EC₅₀ (21 day) = 0.026 mg a.s./L

NOEC (21 day) = 0.015 mg a.s./L

LOEC (21 day) = 0.028 mg a.s./L.

 

Description of key information

The aim of the study was to investigate the toxicity of propineb to Daphnia magna over 21-day study under flow-through conditions. Daphnid were exposed to nominal concentrations of 0.012, 0.024, 0.050, 0.10 and 0.20 mg a.s./L. The 21-d NOEC was determined to be 0.015 mg a.s./L (based on mean measured concentrations).

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Dose descriptor:

NOEC

Remarks:

21 day

Effect concentration:

0.015 mg/L

Additional information

A study that was not included in the summary was performed by Beltman, 2005. The aim of the study was to assess the effect and potential recovery of repeated applications of propineb on a mixed age population of Daphnia magna in aquatic laboratory test systems. The treatment consisted of 4 applications of propineb at one week intervals. The treatment levels were: 60, 120, 240, 480, and 960 μg a.s./L in triplicate aquaria (n=3). Three aquaria served as controls. The NOEC was determined to be 480 µg a.s./L.

Another study not included in the summary was performed by Burgess, 1990. This study involved a five concentration plus control 21-day chronic life-cycle study with Daphnia magna exposed to propineb. This study was conducted to satisfy the data requirements of U.S. EPA-FIFRA, 40 CFR, Section 158.145, Guideline 72-4. The nominal test concentrations were 0.012, 0.024, 0.050, 0.10 and 0.20 mg formul./L. The NOEC was determined to be 0.018 mg a.s./L.