4,4'-methylenebis(cyclohexylamine)

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

15 Feb 1988 to 19 Feb 1988

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Test procedure according to national standards

Qualifier:

according to guideline

Guideline:

other: German industrial standard test guideline DIN 38 412, part L15.

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: The concentrations were chosen based on a range finding study.
LC50 after 96 h: between 10 and 100 mg/L
The product was added to the test water without any pretreatment; subsequently the fish were placed into the aquaria

To study the effect of the high ph on the toxicity the concentration 100 mg/l was tested in parallel after ph-adjustment with hydrochloric acid.

Test organisms (species):

Leuciscus idus

Details on test organisms:

TEST ORGANISM
- Common name: Goldorfe
- Strain: Leuciscus idus (golden variety)
- Source: Fischzucht Paul Eggers, 2354 Hohenwestedt, Germany
- Length at study initiation: 8.1 cm (range: 7.2 - 9.3)
- Weight at study initiation: 5.3 g (range: 3.6 - 8.3)
- Feeding during test: no
- Frequency: Withdrawal of food before exposure: 1 day


ACCLIMATION
- Acclimation conditions (same as test or not): oil-free aerated and acitive carbon filtered tap water, flow-through system
Water temperature: 15 - 20 °C
Acclimation to test water and test temperature: 3 days

- Type and amount of food: Growing feed, F/B 50, SSNIFF Spezialdiaeten GmbH, Soest, Germany
- Feeding frequency: ad libitum.

HOUSING
- Housing water: acitive carbon filtered dechlorinated water in continuous flow-through
- Aeration: oilfree air
- Light regime: 16 : 8 hours light : dark
- Hardness: 2.5 mM
- Oxygen concentration: > 60 % of maximum saturation
- pH: about 8.0
- Water temperature: 15 - 20 °C
- Duration of housing: about 3 months
- Medical treatment: Twice with 0.05 mg/L Malachitegreen and once with 10 mg/L tetracyclinhydrochlorid
- Feeding: Growing feed, F/B 50, SSNIEF Spezialdiaeten GmbH, Soest, Germany
- Amount of feed: ad libitum
- Mortality during the last 2 weeks of housing: 0.03 %

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

96 h

Hardness:

Total hardness: 2.5 mmol/L
Acid capacity: 0.8 mmol/L

Test temperature:

20 - 21 °C

pH:

7.3 (10 mg/L; 72 hrs) - 10.2 (100 mg/L; 1 hrs)

Dissolved oxygen:

7.1 (10 mg/L; 96 hrs) - 8.8 mg/L (100 mg/L pH adjusted; 96 hrs)

Nominal and measured concentrations:

Nominal concentrations: 0, 10, 21.5, 46.4, 100 mg/L. Additionally: Neutralised samples: 100 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Type (delete if not applicable): aquaria open
- Material, size, fill volume: glass, 30 x 22 x 24 cm, 10 L
- Aeration: aeration with oil-free air
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- Biomass loading rate: 5.3 g fish /L

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: reconstituted freshwater according to DIN 38412, part 11
- Ca/Mg ratio: 4 : 1
- Intervals of water quality measurement: 1, 24, 48, 72, and 96 hours

OTHER TEST CONDITIONS
- Photoperiod: 16:8 hour light:dark

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : mortality, symptoms after 1, 4, 24, 48, 72, and 96 h

Reference substance (positive control):

yes

Remarks:

Chloracetamid

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: based on pH-adjusted test solution

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

68 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: geometrical mean (LC50 between 46.4 and 100 mg/L); based on not pH-adjusted test solutions

Duration:

96 h

Dose descriptor:

LC0

Effect conc.:

46.4 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: based on not pH-adjusted test solutions

Duration:

96 h

Dose descriptor:

LC100

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: based on not pH-adjusted test solutions

Details on results:

- An adjustment of the pH resulted in a significant but not complete detoxification of the test substance at 100 mg/L (10% mortality after 72h).
- Behavioural abnormalities: no symptoms

Results with reference substance (positive control):

- Results with reference substance valid? yes
- LC50: ca. 32 mg/L (48 h)

Reported statistics and error estimates:

The LC50 was calculated according to OECD 203 by forming the geometric mean of the highest concentration causing no mortality and the lowest concentration producing 100% mortality.

Sublethal observations / clinical signs:

Cumulative mortality

Nominal conc.(mg/l)	Number of fish	Mortality (cumulated) after
		1 h	4 h	24 h	48 h	72 h	96 h
0	10	0	0	0	0	0	0
10	10	0	0	0	0	0	0
21.5	10	0	0	0	0	0	0
46.4	10	0	0	0	0	0	0
100	10	10	10	10	10	10	10
100*	10	0	0	0	0	1	1

* = pH adjusted

pH values

Nominal conc.(mg/l)	pH values after
	1 h	24 h	48 h	72 h	96 h
0	8.2	8.2	8.0	7.7	7.8
10	8.2	8.0	7.5	7.3	7.5
21.5	8.6	8.0	7.6	7.5	7.6
46.4	9.3	8.0	7.6	7.6	7.6
100
100*	8.3	8.0	7.5	7.6	7.7

* = pH adjusted

Oxygen concentration [mg O2/L]

Nominal conc.(mg/l)	Oxygen concentrations after
	1 h	24 h	48 h	72 h	96 h
0	8.1	7.5	8.1	8.0	8.0
10	8.6	7.5	8.1	7.7	7.1
21.5	8.6	7.4	7.9	8.1	7.5
46.4	8.3	8.1	8.6	8.7	8.4
100
100*	7.7	8.4	8.7	8.5	8.8

* = pH adjusted

Validity criteria fulfilled:

yes

Conclusions:

Based on the nominal concentrations of the test item the 96-hour LC50 for fish was 68 mg/L based on non pH-adjusted test solutions and >100 mg/L based on pH-adjusted solutions.

Executive summary:

The toxicity of the test item was determined according to the German industrial standard test guideline DIN 38 412, part L15 with the golden orfe.

The study was conducted under static conditions over a period of 96 hours with five nominal test concentrations: 0, 10, 21.5, 46.4, 100 mg/L. Additionally, in order to study the effect of the high pH on the toxicity the concentration 100 mg/l was tested in parallel after pH-adjustment.

Ten fish per concentration level and the control were exposed to the test item in a glass tanks containing 10 L of test solution. Oxygen saturation, pH values, mortality and symptoms were monitored after 1, 4, 24, 48, 72, and 96 h.

Based on the nominal concentrations of the test item the 96-hour LC50 for fish was 68 mg/L based on non pH-adjusted test solutions and >100 mg/L based on pH-adjusted solutions.

Description of key information

The short-term LC50 value for fish was based upon the 96 -hour LC50 > 100 mg/L (nominal concentration; pH-adjusted) in Leuciscus idus reported in the key study (BASF AG, 1988).

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Dose descriptor:

LC50

Effect concentration:

100 mg/L

Additional information

The acute toxicity of PACM (CAS 1761 -71 -3) was studied in a static test according to German Industrial Standards DIN 38412, part 15 using Leuciscus idusas test species (BASF AG, 1988; report no. BASF AG 10F0562/875273). The test concentrations were not analytically verified, but are assumed to be stable regarding the low biodegradation potential and the low Henry's Law Constant of 9.6E-08 Pa*m³/mol at pH 7.

 

The 96 -h LC₅₀ was determined to be 67.8 mg/L from the non-pH-adjusted series of test concentrations (nominal; geometric mean; not pH-adjusted). For the pH-adjusted solution a 96 -h LC₅₀of > 100 mg/L (nominal concentration; pH-adjusted solution) was reported.

 

The toxic effect was significantly reduced after pH-adjustment (at 100 mg/L: 100% mortality without pH adjustment, 10% mortality after pH adjustment). However, the 96 -hour LC₅₀ of >100 mg/L for Leuciscus idus was the representative value for the short-term toxicity of 4,4'-methylenebis(cyclohexylamine) to fish since the test substance led to an increase of the pH (pH 10.2 at 100 mg/L) above the recommended range of 6.0 - 8.5 (OECD 203).

The study should be conducted at a pH consistent with the most toxic form, but, if the test chemical itself causes a change to the pH of the test solution, the pH should be adjusted to lie within the specified range prior to addition of the test organisms (OECD 23). Thus, using the LC50 based on pH adjusted solutions is justified.

 

This value represented one of the three short-term aquatic toxicity values for each of three trophic levels (fish, aquatic invertebrates and aquatic algae and plants). The lowest of the three short-term aquatic toxicity values from each of the three trophic levels was used as the point of departure for the derivation of the PNEC_{aquatic (freshwater)}.