cis-4-[3-(p-tert-butylphenyl)-2-methylpropyl]-2,6-dimethylmorpholine

Long-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

fish early-life stage toxicity

Type of information:

experimental study

Adequacy of study:

key study

Study period:

07.11.1994- 10.02.1995

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 210 (Fish, Early-Life Stage Toxicity Test)

Version / remarks:

Nov. 1990

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

Fenpropimorph, batch no. OP 28791328, purity: 95.6%

Analytical monitoring:

yes

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

TEST ORGANISM
- Common name: Rainbow trout
- Strain: Oncorhynchus mykiss WALBAUM 1792
- Source: Institute for Animal Breeding and Genetics of Domestic animals of the University Göttingen, FRG, November 7, 1994

METHOD FOR PREPARATION AND COLLECTION OF FERTILIZED EGGS
- Numbers of parental fish (i.e. of females used to provide required number of eggs): pool of 6 males and 6 females
- Method of collection of fertilised eggs: Eggs and sperm were gained in the
late morning of November 7, 1994 in Gottingen and were transported in adequate containers by express train to the BASF laboratory.
- Subsequent handling of eggs: In the BASF laboratory, in the late afternoon, the eggs were placed in a bowl and combined with sperm (approx. 10 minutes). After
being gently mixed the embryos were covered with dilution water (temperature approx. 10°C). After approximately 10 minutes to water harden the embryos
were rinsed several times with dilution water at approx. 10°C, and the embryos were placed in aerated water at approx. 10°C under flow—through condition.
The eggs (embryos) did not receive any disinfection or medical treatment. The eggs were placed in the exposure chambers approx. 16 hours (Nov. 8, 1994) after fertilization and all eggs (embryos) appeared to be in good condition at the beginning of the study.

POST-HATCH FEEDING
- Start date: Beginning at swimm-up
- Type/source of feed: combination of live, newly hatched artemia and trout starter ("Kronen-Fisch Aminostart", supplied by Ssniff, Spezialdiaten GmbH, Soest, FRG)
- Frequency of feeding: at least on workdays

Test type:

flow-through

Water media type:

freshwater

Limit test:

no

Total exposure duration:

94 d

Hardness:

0.50 mmol/l (approx. 50 mg/l as CaCO3)

Test temperature:

10°C

pH:

8.2 ± 0.2

Dissolved oxygen:

80% - 100% of maximum saturation

Conductivity:

78- 92 µS

Nominal and measured concentrations:

nominal concentrations: 0 (control), 0.00016, 0.0008, 0.004, 0.02 and 0.1 mg/l;
Mean measured concentrations were (% of nominal):
Control none detected = 0%; 0.00016 mg/l = 106.0%; 0.0008 mg/l = 90.5%; 0.004 mg/l = 98.8%; 0.02 mg/l = 96.1% and 0.1 mg/l = 98.3% of the nominal values

The results are therefore based on nominal concentrations.

Details on test conditions:

TEST SYSTEM
- Emybro cups (if used, type/material, size, fill volume): cylinders made of transparent glas, diameter 12 cm, 10 cm high, with a stainless steel grid (3 x 3 mm)
- Test vessel: all-glass aquaria
- Material, size, headspace, fill volume: glass; 29 cm long, 21 cm wide and 22 cm high; constant water volume of approx. 9 liters in each aquarium; water depth: approx. 15 cm
- Aeration: always fresh aerated water or test solution passed
the embryos
- Type of flow-through (e.g. peristaltic or proportional diluter):
- Renewal rate of test solution (frequency/flow rate): approximately 2.5 l/hour for each aquarium (theoretical exchange rate of the water contents was approximately 6.7 exchanges per 24 hours)
- No. of fertilized eggs/embryos per vessel: 30, reduced to 25 per replica after 24h and reduced to 15 per replicate on day 34
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 2
- Biomass loading rate: 0.16 mg/L

TEST MEDIUM / WATER PARAMETERS
- Source of dilution water: non-chlorinated drinking water obtained from the municipal water works of the city of Frankenthal, purified over charcoal and aerated (fish laboratory quality) and was adjusted by addition of deionized water


OTHER TEST CONDITIONS
- Adjustment of pH: pH 91, WTW, Weilheim, FRG with electrode type E50: pH Einstabmeßkette (single rod-measuring device)
- Photoperiod: 16 hours light and 8 hours darkness
- Light intensity: about 100 Lux under the lid


RANGE-FINDING STUDY
- Results used to determine the conditions for the definitive study: preliminary flow—through embryo—larvae study on the rainbow trout with Fenpropimorph for a period of 95 days: 50% mortality at concentration 0.1 mg/l

Duration:

94 d

Dose descriptor:

LOEC

Effect conc.:

0.8 µg/L

Nominal / measured:

meas. (initial)

Conc. based on:

test mat.

Basis for effect:

mortality

Key result

Duration:

94 d

Dose descriptor:

NOEC

Effect conc.:

0.16 µg/L

Nominal / measured:

meas. (initial)

Conc. based on:

test mat.

Basis for effect:

mortality

Details on results:

Analytical measurements: The mean analytically determined concentration values of the test compound in the test water were within a range of 90.5% - 106.0% of the nominal concentrations. Therefore the following biological results are based on nominal concentrations.

Biological results: At day 2 of exposure and at the beginning of the hatch there was no compound-related effect. At study termination the survival rate was statistically significantly impaired in all test compound containing groups. Considering the absolute figures for the survival rates in the lowest dose group (mean of 4 replicates 98% (93% - 100%) it is concluded that there is no statistically and/or biologically relevant effect on the survival rate in this group resulting in a NOAEL of 0.00016 mg/L for overall survival. As hatch and swim-up occurred nearly synchronically there was no biologically significant difference between compound groups and the control group.
From day 69 to 70 onward, in the two highest test groups (0.02 mg/L and 0.1 mg/L), from day 77 onward also in the lower concentration next to 0.02 mg/L (0.004 mg/L) compound-related onset of toxic signs could be observed, generally increasing in strength and quality with the duration of the study and increasing concentration, such as apathy, discoloration, narcotic-like state, tumbling and swimming near the water-surface. This resulted in a NOAEC for toxic signs of 0.0008 mg/L.
The mean wet weight and total length of the animals at the termination of the study were statistically significantly impaired in more or less concentration-dependent manner in all groups containing the test compound. In the lowest dose group the impairment of the body weight compared to the control group was only 11% and of the body length about 5%. This was not considered to be detrimental for the survival of a population. Hence, it is suggested that the NOAEL for the impairment of the development of body weight and length is expected at the lowest concentration (0.00016 mg/L).

Table 1:  Early life stage test (94 d) of Fenpropimorph on rainbow trout (Oncorhynchus mykiss)
Concentration [mg a.s./L] nominal	Control	0.00016	0.0008	0.004	0.02	0.1
Start of hatch [day]	34	34	34	34	34	34
Survival of larvae at day 34 related to day 2 [%]	94	95	95	94	99	96
Time to swim-up [day]	52	52	52	52	52	52
Survival of larvae at day 52 related to day 34 [%]	100	98.3	96.7	96.7	95	96.7
Survival of young fish at day 94 related to day 52 survivors [%]	93.3	98.3	79.8	48.6	59.8	35.3
Mean wet weight [% of control]	100	89.1	59.8	42.3	33.1	29.2
Mean body length [% of control]	100	95.1	85.7	75.5	68.0	65.5
Symptoms	none	none	S*, G*	C, N*, T*	A, C, N*, V	S*, A, C, N, T*

* = One specimen only     
Symptoms: A = apathy; C = swimming near the water surface; G = reduced or no feed consumption; N = narcotic state;               S = side position; T = tumbling, V = discoloration

 

 

The mean survival rates of the young fish and the ranges for the respective 4 replicates (in brackets) were:

	mg/l (Control):	mean 93% (87 - 100%)
0.00016	mg/l:	mean 98% (93 - 100%)
0.0008	mg/l:	mean 80% (67 -   92%)
0.004	mg/l:	mean 49% (27 -   64%)
0.02	mg/l:	mean 60% (43 -   71%)
0.1	mg/l:	mean 35% ( 8  -   47%)

Conclusions:

Embryos, larvae and juvenile fish of the rainbow trout (Oncorhynchus mykiss WALBAUM 1792) were exposed to "Fenpropimorph" with the concentrations 0
(Control); 0.00016; 0.0008; 0.004; 0.02 and 0.1 mg/l.
The relevant biological parameters were monitored.
In conclusion, under the conditions of this study, an overall NOAEL (no observed adverse effect level) of 0.00016 mg/l (lowest concentration tested) is
suggested (nominal value). The concentration control analyses confirmed the
nominal concentrations of the test compound in the test water.

Description of key information

In an early life stage study (DocID: 1995/10517) of fenpropimorph on rainbow trout an overall NOAEL (no observed adverse effect level) of 0.00016 mg a.s./L (initially measured) was determined.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

0 mg/L

Additional information

The purpose of the study by Munk et al. (1995) was to estimate the chronic toxicity of fenpropimorph to early life stages of Rainbow trout (Onchorhynchus mykiss WALBAUM 1792) under flow-through conditions. The study was conducted according to EPA Guideline 72-4 (a) and OECD Guideline 210 (1992). This test resulted in the most sensitive effect values (NOAEL = 0.00016 mg/L, nominal value) and is chosen as key study.

Under conditions of a chronic toxicity test on juvenile rainbow trouts (Dommroese A.-M., 1989(a), 1989/0571), the 21-day NOEC was determined to be 0.1 mg a.s./L (analytically measured).

Additional studies, using formulated producs of fenpropimorph, are existing and are summarized below.
Chronic effects of BAS 492 01 F (formulated product, containing 300 g fenpropimorph/L plus 150 g kresoxim-methyl/L) on juvenile fish - Leuciscus idus L. 'golden variety' - were tested under more realistic exposure conditions in small field microcosms (BASF AG, Dohmen G.P.; 2002/1011545, 2003/1014085).
The results showed that the formulated product had no negative impact on fish following two exposures with initial concentrations up to 40 µg/L, according to Fenpropimorph concentrations of 12 µg/L.

Another modified early-life-stage test of the effects of BAS 421 12 F, another formulated product, containing 743.6 g fenpropimorph/L, on rainbow trouts (Oncorhynchus mykiss) using more realistic exposure conditions resulted in an overall NOEC of 0.003 mg a.s./L (nominal) (BASF SE, Zok, S., 2005/1005782)