Hexylamine

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:

29/07/2016 to 02/08/2016

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

Experimental test result performed according to the guideline.

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Principles of method if other than guideline:

Study was conducted to access the effect of test chemical on the mortality of fish Danio rerio. Test conducted according to OECD Guideline 203 (Fish, Acute Toxicity Test).

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

The test substance was soluble in water, In house solubility was found to be 1100.77 mg/L. Therefore the stock solution prepared as 52.7ml /2 liter, with the concentration of 2g/100ml, and was kept for 2 hours stirring. After the completion of stirring, the sample was kept for settling and filtered it. After this as it is stock taken for experiment. From this stock solution further test concentrations were prepared for achieving test concentrations of 0.98 mg/L, 1.48 mg/L, 2.22mg/L, 3.33mg/L, 5 mg/L respectively.

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

TEST ORGANISM
- Common name: Zebra Fish
- Strain: Danio rerio
- Source: Unique Aqua Fish Corner
- Length at study initiation (length definition, mean, range and SD): average 3.42cm
- Weight at study initiation (mean and range, SD): Average 0.335 gm
-Housing:The fishes were kept in a static tank in tap water passed through reverse osmosis system, under natural conditions along with proper feed and aeration.
-Duration of housing: 15 days
-Photoperiod: 12 hours light and 12 hours darkness
-Diet : Standard brand feed, once daily

-Acclimatization: seven days
Photoperiod 12 hours light and 12hour darkness
Temperature range: 24°C
pH range: 7.55
DO range: 6.7 mg/l
Feeding : Once in a day up to sixth day of acclimatization
Aeration: Continuous aeration was provided
Mortality (%) During last 48 hours = 0%

Test type:

static

Water media type:

freshwater

Total exposure duration:

96 h

Hardness:

141 mg of CaCO3

Test temperature:

23°C

pH:

7.01

Dissolved oxygen:

11.5

Nominal and measured concentrations:

Nominal concentration 0.98 mg/L, 1.48 mg/L, 2.22mg/L, 3.33mg/L, 5 mg/L.

Details on test conditions:

TEST SYSTEM
- Test vessel: Plastic aquaria
- Material, size, headspace, fill volume: 5 liters of plastic aquaria filled with 2 liter of water
- Aeration: Aeration in test vessels was provided 1 day before the start of experiment
- No. of organisms per vessel: 8 fishes

OTHER TEST CONDITIONS
- Photoperiod: 12 hours light and 12-hour darkness

Reference substance (positive control):

no

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 2.22 - < 3.33 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: Other details not known

Duration:

96 h

Dose descriptor:

LC0

Effect conc.:

2.22 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other: Other details not known

Sublethal observations / clinical signs:

Table 1: Mortality and symptoms

NominalConcentration (mg/l)	Number of fish		Mortality (cumulated) after
			3 h		6 h		24h			48h		72h		96h
			V1	V2	V1	V2	V1	V2		V1	V2	V1	V2	V1	V2
0 (control)	4	4	-	-	-	-	-		-	-	-	-	-	-	-
0.98	4	4	-	-	-	-	-		-	-	-	-	-	-	-
1.48	4	4	-	-	-	-	-		-	-	-	-	-	-	-
2.22	4	4	-	-	-	-	-		-	-	-	-	-	-	-
3.33	4	4	4	4	4	4	4		4	4	4	4	4	4	4
5	4	4	4	4	4	4	4		4	4	4	4	4	4	4

 Visible Symptoms:

NominalConcentration (mg/l)

Number of fish

Symptoms after

3 h

6 h

24h

48h

72h

96h

V1

V2

V1

V2

V1

V2

V1

V2

V1

V2

V1

V2

0 (control)

4

4

NS4

NS4

NS4

NS4

NS4

NS4

NS4

NS4

NS4

NS4

NS4

NS4

0.98

4

4

M4

M4

M4

M4

M4

M4

M4

M4

M4

M4

M4

M4

1.48

4

4

M4

M4

M4

M4

M4

M4

M4

M4

M4

M4

M4

M4

2.22

4

4

M4

M4

M4

M4

M4

M4

M4

M4

M4

M4

M4

M4

3.33

4

4

-

-

-

-

-

-

-

-

-

-

-

-

5

4

4

-

-

-

-

-

-

-

-

-

-

-

-

 

Explanation of symptoms:

A:apathy

N:Narcotic-like state

C:Swimming near water surface

M: Slow movements compared to control

NS:No abnormal symptoms 

S:Surfacing behaviour

L:Loss of equilibrium

SM:Shimming movement

H1:Hyperactivity

H2:Hypo activity

B:Bending behavior

F:Fin rot

IS:Invert Swimming

SB:Swimming behaviour

RF:Respiratory Function

P:Pigmentation

 

Table 2. pH and oxygen content:

NominalConcentration (mg/l)	Number of fish		pH readings after
			24h			48h		72h		96h
			V1	V2		V1	V2	V1	V2	V1	V2
0 (control)	4	4	7.98		7.99	7.98	7.99	8.17	8.14	8.05	8.04
0.98	4	4	7.96		7.97	7.96	7.97	8.01	8.01	8.10	8.04
1.48	4	4	7.57		7.58	7.57	7.58	8.17	8.17	8.05	8.06
2.22	4	4	8.01		8.02	8.01	8.02	8.18	8.18	8.10	8.10
3.33	4	4	-		-	-	-	-	-	-	-
5	4	4	-		-	-	-	-	-	-	-

 

NominalConcentration (mg/l)	Number of fish		Oxygen content (mg/L) after
			24h			48h		72h		96h
			V1	V2		V1	V2	V1	V2	V1	V2
0 (control)	4	4	11.5		11.9	11.5	11.9	11.3	11.2	9.7	10.7
0.98	4	4	10.6		10.7	10.6	10.7	9.7	9.9	6.8	6.4
1.48	4	4	9.1		9.8	9.1	9.8	9.6	9.6	6.6	6.5
2.22	4	4	9.6		9.7	9.6	9.7	7.5	7.5	6.5	5.0
3.33	4	4	-		-	-	-	-	-	-	-
5	4	4	-		-	-	-	-	-	-	-

 

Table 3: Test temperature:

NominalConcentration (mg/l)	Number of fish		Temperature (°C) after
			24h			48h		72h		96h
			V1	V2		V1	V2	V1	V2	V1	V2
0 (control)	4	4	23		23	23	23	22	22	23	23
0.98	4	4	23		23	23	23	22	22	23	23
1.48	4	4	23		23	23	23	22	22	23	23
2.22	4	4	23		23	23	23	22	22	23	23
3.33	4	4	-		-	-	-	-	-	-	-
5	4	4	-		-	-	-	-	-	-	-

Validity criteria fulfilled:

yes

Conclusions:

Based on nominal concentrations, experimental median lethal Concentrations [LC-50 (96 h)] for test chemical on Zebra Fish Danio rerio was determine to be >2.22mg/l and <3.33 mg/l as no effect were observed at 2.22 mg/l.

Executive summary:

Study was conducted to assess the effect of test chemical on the mortality of fish Danio rerio. Test conducted according to OECD Guideline 203 (Fish, Acute Toxicity Test). The test substance was soluble in water, In house solubility was found to be 1100.77 mg/L. Therefore the stock solution prepared as 52.7ml /2 liter, with the concentration of 2g/100ml, and was kept for 2 hours stirring. After the completion of stirring, the sample was kept for settling and filtered it. After this as it is stock taken for experiment. From this stock solution further test concentrations were prepared for achieving test concentrations of 0.98 mg/L, 1.48 mg/L, 2.22mg/L, 3.33mg/L, 5 mg/L respectively and Zebra Fish Danio rerio were exposed to these concentration for 96 hours. Plastic aquaria containing 5 liters of potable water (passed through reverse osmosis system) were loaded with 8 fishes. A static procedure was used for the study and it was conducted in compliance with the OECD guideline 203. After 96 hours of exposure to test item to various nominal test concentrations, LC50 was determine to be >2.22mg/l and <3.33 mg/l as no effect were observed at 2.22 mg/l. Based on the LC50, it can be consider that the chemical was toxic and can be consider to be classified in aquatic chronic 2 category as per the CLP classification criteria.

Description of key information

Study was conducted to assess the effect of test chemical n- hexylamine (CAS 111-26-2) on the mortality of fish Danio rerio. Test conducted according to OECD Guideline 203 (Fish, Acute Toxicity Test). The test substance was soluble in water, In house solubility was found to be 1100.77 mg/L. Therefore the stock solution prepared as 52.7ml /2 liter, with the concentration of 2g/100ml, and was kept for 2 hours stirring. After the completion of stirring, the sample was kept for settling and filtered it. After this as it is stock taken for experiment. From this stock solution further test concentrations were prepared for achieving test concentrations of 0.98 mg/L, 1.48 mg/L, 2.22mg/L, 3.33mg/L, 5 mg/L respectively and Zebra Fish Danio rerio were exposed to these concentration for 96 hours. Plastic aquaria containing 5 liters of potable water (passed through reverse osmosis system) were loaded with 8 fishes. A static procedure was used for the study and it was conducted in compliance with the OECD guideline 203. After 96 hours of exposure to test item to various nominal test concentrations, LC50 was determine to be >2.22mg/l and <3.33 mg/l as no effect were observed at 2.22 mg/l. Based on the LC50, it can be consider that the chemical was toxic and can be consider to be classified in aquatic chronic 2 category as per the CLP classification criteria.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

3.33 mg/L

Additional information

Based on the short term toxicity study available for the test chemical, studies were reviewed to determine the toxic nature of test chemical n- hexylamine (CAS 111-26-2) on the mortality of fish. The studies are as mentioned below:

 

In the first key experimental study was conducted to assess the effect of test chemical n- hexylamine (CAS 111-26-2) on the mortality of fish Danio rerio. Test conducted according to OECD Guideline 203 (Fish, Acute Toxicity Test). The test substance was soluble in water, In house solubility was found to be 1100.77 mg/L. Therefore the stock solution prepared as 52.7ml /2 liter, with the concentration of 2g/100ml, and was kept for 2 hours stirring. After the completion of stirring, the sample was kept for settling and filtered it. After this as it is stock taken for experiment. From this stock solution further test concentrations were prepared for achieving test concentrations of 0.98 mg/L, 1.48 mg/L, 2.22mg/L, 3.33mg/L, 5 mg/L respectively and Zebra Fish Danio rerio were exposed to these concentration for 96 hours. Plastic aquaria containing 5 liters of potable water (passed through reverse osmosis system) were loaded with 8 fishes. A static procedure was used for the study and it was conducted in compliance with the OECD guideline 203. After 96 hours of exposure to test item to various nominal test concentrations, LC50 was determine to be >2.22mg/l and <3.33 mg/l as no effect were observed at 2.22 mg/l. Based on the LC50, it can be consider that the chemical was toxic and can be consider to be classified in aquatic chronic 2 category as per the CLP classification criteria.

 

Another study from peer reviewed journal was also conducted. The objective of this study was to investigate the use of 96-h acute toxicity tests with juvenile fathead minnows and binary chemical mixtures to define the primary acute model of toxic action for diverse industrial organic chemicals. The 96-h acute toxicity tests with single chemicals and mixtures, and 26- to 34-d-old laboratory-cultured juvenile fathead minnows (Pimephalespromelas) were conducted. The experiments with mixtures were carried out under similar conditions as the experiments with single compounds. Exposures were conducted at 25°C in continuous flow-through systems with four or five toxicant concentrations and a control in duplicate for each LC50 determination. Toxicant concentrations in the test chambers were continuously renewed and measured daily. Methods of chemical analysis included high-pressure liquid chromatography (HPLC) and gas-liquid chromatography (GC). Toxicant concentrations were routinely corrected for spiked water recoveries. Percentage duplicate agreements were usually greater than 90%. The dilution water was taken directly from Lake Superior, and following sand filtration. It had a water hardness, alkalinity, and pH of approximately 45 mg/L as CaC03, 42mg/L as CaC03, and 7.8, respectively, for all tests. All toxicity tests were conducted without using solvent carriers. Mortalities were recorded daily and estimate of the concentration of toxicant most likely to cause 50 % mortality (LC50). The Lethal concentration causing 50% mortality value (LC50) of1 Pimephales promelas (Fathead Minnow) was determine to be 56.6 mg/L after 96 hours of exposure to test chemical. This lethal value indicates that the test substance n- hexylamine classified in aquatic category 3 as per the CLP criteria.

 

Above study was supported by the third study from peer reviewed journal. Aim of this study was to determine the effect of test chemical n- hexylamine on the mortality of fish Pimephales promelas for 96 hrs. Test conducted under the flow-through system. The Lethal concentration causing 50% mortality (LC50) of fathead minnow when exposed to test chemical for 96 hours under the test conditions is 56.23mg/l. It is reported to be bioactive. Thus based on the LC50 value, chemical consider to be toxic and classified as aquatic chronic 3 as per the CLP classification criteria.

 

Similarly in a 96 hour short team toxicity study, the effect of test chemical n- hexylamine was evaluated on Pimephales promelas (Fathead Minnow). The test substance was test in a concentration of 56.6 mg/l (53.8 to 59.6 mg/l). The results show 50% mortality of test organism’s population at given concentration. Therefore, chemical considered to be lethal at 56.6 mg/l (56600 mg/l) when tested on Pimephales promelas (Fathead Minnow) for 96 hrs. Thus considering the CLP Criteria for aquatic classification of the substance, it is concluded that the test chemical classified in aquatic chronic category 3.

 

Similarly Test for acute toxicity was carried out on embryos of Danio rerio. The effects of basicity were investigated adjusting pH´s of 8.0 to 12.0 using a 0.1 n NaOH – solution after 48 h for lethal and sub lethal effects. The lethal concentration (LC50) for embryos of Danio rerio zebrafish was considered to be 42.31mg/l (32.18-46.45 mg/l) when exposed to test chemical for 48 hours. Thus according to lethal concentration the test substance consider to be toxic to fish and thus classified in aquatic chronic category 3.

 

Thus based on the above studies from experimental study report, peer reviewed journal and secondary sources, it was concluded that the chemical n- hexylamine (CAS 111-26-2) was toxic and classified in aquatic chronic category 2.