1-fluoro-2-nitrobenzene

Repeated dose toxicity: inhalation

Administrative data

Endpoint:

short-term repeated dose toxicity: inhalation

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 06 November To 08 March 1976

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Study well conducted, sufficiently detailed, according to standardised guidelines, but not GLP.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1976

Report date:

1976

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

Male and female rats were exposed to the test substance for 4 hours per day, 6 days per week during 4 weeks. Following the exposure, a rest period of 4 weeks was performed. Hematology examinations were performed at 2, 4, 6 and 8 weeks. Clinical Biochemistry examinations were performed at the end of the exposure (4 weeks). Histology and necropsy were also performed at the end of the exposure.

GLP compliance:

no

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

1-fluoro-4-nitrobenzene

EC Number:

206-502-8

EC Name:

1-fluoro-4-nitrobenzene

Cas Number:

350-46-9

Molecular formula:

C6H4FNO2

IUPAC Name:

1-fluoro-4-nitrobenzene

Details on test material:

- Physical state: pale yellow liquid
- Density: 1.30

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

No data

Administration / exposure

Route of administration:

inhalation: vapour

Type of inhalation exposure:

whole body

Vehicle:

air

Details on inhalation exposure:

GENERATION OF TEST ATMOSPHERE / CHAMBER DESCRIPTION
- Exposure apparatus: Glass chamber
- Exposure chamber volume: 100 L with flow rate of 500L/h


OTHER:
Each day, the product was diluted in ethanol (CAS: 64-17-5)
- Solution (3) = 130 mg/m3 (0.050 ml/heure)
Product 4 ml + ethanol 11.2 ml
- Solution (2) = 40 mg/m3 (0.015 ml/heure)
Product 1.5 ml + ethanol 17.5 ml
- Solution (1) = 130 mg/m3 (0.005 ml/heure)
Dilution 1/10 of solution 3
solution (3) 1 ml + ethanol 9 ml

Analytical verification of doses or concentrations:

not specified

Duration of treatment / exposure:

4 hours

Frequency of treatment:

6 days per week for 4 weeks

Doses / concentrations

Remarks:

Doses / Concentrations:
13, 40 and 130 mg/m3 (0.013, 0.04 and 0.13 mg/l)
Basis:
nominal conc.

No. of animals per sex per dose:

8 per dose per sex

Control animals:

yes, concurrent vehicle

Details on study design:

Exposure time: 4 hours, 6 days a week and for 4 weeks, with 4 weeks of reversibility.
After 4 weeks of treatment, 5 males and 5 females per dose were sacrified in order to examine haematology (hemoglobinemia, numeration, erythrocytes and leucocytes), biochemistry (urea and bilirubin) and necropsy.
Other animals were observed during 4 weeks (reversibility).
Haematology was examined after 2 and 4 weeks for animals sacrified after 4 weeks, after 6 and 8 weeks for the others.

Examinations

Observations and examinations performed and frequency:

CAGE SIDE OBSERVATIONS: No

DETAILED CLINICAL OBSERVATIONS: No

BODY WEIGHT: No

FOOD CONSUMPTION:
- Food consumption for each animal determined and mean daily diet consumption calculated as g food/kg body weight/day: No

FOOD EFFICIENCY:
- Body weight gain in kg/food consumption in kg per unit time X 100 calculated as time-weighted averages from the consumption and body weight gain data: No

WATER CONSUMPTION: No

OPHTHALMOSCOPIC EXAMINATION: No

HAEMATOLOGY: Yes
- Time schedule for collection of blood: at 2, 4, 6 and 8 weeks
- Anaesthetic used for blood collection: yes
- Animals fasted: No data
- How many animals: 5 per sex at the end of exposure/ 3 per sex after a week of rest.
- Parameters checked in table [No.1] were examined.

CLINICAL CHEMISTRY: Yes
- Time schedule for collection of blood: at the end of the exposure (4 weeks).
- Animals fasted: No data
- How many animals: 5 per sex.
- Parameters checked in table [No.1] were examined.

URINALYSIS: yes

NEUROBEHAVIOURAL EXAMINATION: No

Sacrifice and pathology:

GROSS PATHOLOGY: Yes
HISTOPATHOLOGY: YES (Histopatology of heart, lung, liver, spleen, kidneys and adrenal glands was performed)

Results and discussion

Results of examinations

Clinical signs:

no effects observed

Mortality:

no mortality observed

Body weight and weight changes:

not examined

Food consumption and compound intake (if feeding study):

not examined

Food efficiency:

not examined

Water consumption and compound intake (if drinking water study):

not examined

Ophthalmological findings:

not examined

Haematological findings:

effects observed, treatment-related

Clinical biochemistry findings:

effects observed, treatment-related

Urinalysis findings:

not examined

Behaviour (functional findings):

not examined

Organ weight findings including organ / body weight ratios:

no effects observed

Gross pathological findings:

no effects observed

Histopathological findings: non-neoplastic:

not examined

Histopathological findings: neoplastic:

not examined

Details on results:

CLINICAL SIGNS AND MORTALITY
No mortality related to test substance was observed and no clinical signs were reported. One female died due to an anesthesic accident.

HAEMATOLOGY
After 2 weeks of treatment, no effect was observed in all animals. At the end of the exposure (4 weeks), a slight decrease in the erythrocytes count and a significant decrease of leucocytes count at the highest tested doses were observed. In addition, the methemoglobin increased at 40 mg/m3 (3.3 %) and became anormal at the highest tested dose (4.5 %). After two weeks of rest, all parameters showed comparable values to controls. (For details see Table 1)

CLINICAL CHEMISTRY
No significant effect on clinical biochemistry parameters (sodium, potassium, urea, total protein, alkaline phosphatase and alanine aminotransferase) was observed. (For details see Table 2)


GROSS PATHOLOGY
No effect has been observed.

HISTOPATHOLOGY
An effect of the test substance on the spleen was observed. The number of foci of extramedullary hematopoiesis were increased in the red pulpe of the spleen and were accompanied by an increase of splenic hemosiderin and venous sinus congestion. After 4 weeks of rest, foci of hematopoiesis have decreased in all animals. Only clusters of hemosiderin in macrophages were persistant.

Effect levels

Key result

Dose descriptor:

NOAEC

Effect level:

0.013 mg/L air (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: Effects on spleen

Target system / organ toxicity

Key result

Critical effects observed:

yes

Lowest effective dose / conc.:

0.013 mg/L air (nominal)

System:

haematopoietic

Organ:

blood

spleen

Treatment related:

yes

Dose response relationship:

yes

Relevant for humans:

yes

Any other information on results incl. tables

Table 1: Hematologic results

Time	Groups	H %	Hb g/100 ml	Erytrocyte E+03/mm^3	Leucocytes/mm^3	Methemoglobin
After 2 weeks	Control	45.2 2.17	15.0 0.23	7788 584.6	11880 3565.4	/
	Control (ethanol)	44.3 2.34 -0.63	15.0 0.55 -0.08	7750 245.2 -0.15	9466 2498.5 -1.32	/
	13 mg/m^3	42.7 1.97 -2.03	14.7 0.76 -0.73	7113 491.5 -2.1	10933 4233.0 -0.39	/
	40 mg/m^3	46.0 1.54 0.71	15.5 0.52 2.1	7503 404.7 -0.95	12767 2834.0 0.46	/
	130 mg/m^3	44.1 2.40 -0.74	14.7 0.86 -0.65	7450 395.7 -1.1	12917 2324.0 0.53	/
After 4 weeks	Control	49.3 2.9	15.8 1.0	8777 886	19289 33250	2.36 0.45
	Control (ethanol)	48.3 1.88 -0.93	15.3 0.87 -1.13	8494 552 -0.85	15070 2865 -2.97	2.57 0.35 1.09
	13 mg/m^3	46.6 (-) 1.90 -2.44	15.0 0.76 -1.96	7940 (-) 642 -2.38	13930 (--) 2735 -3.85	2.87 (+) 0.53 2.35
	40 mg/m^3	46.9 2.38 -2.0	14.8 (-) 0;69 -2.4	8004 (-) 436 -2.46	12570 (---) 1865 -5.50	3.25 0.41 4.65 (+++)
	130 mg/m^3	45.2 (--) 2.1 -3.57	14.4 (-) 0.99 -2.97	7724 (-) 676 -2.93	11510 (---) 1995 -6.26	4.54 0.91 6.76 (+++)
After 6 weeks	Control	45.3 4.3	15;6 0.23	8183 368	9983 1762	/
	Control (ethanol)	50.0 1.8 1.77	16.0 0.34 2.08	7866 457 -1.32	10516 2125 0.47	/
	13 mg/m^3	49.0 1.8 1.94	15.9 0.64 0.83	7953 573 -0.83	11867 4694 0.92	/
	40 mg/m^3	49.8 2.9 2.14	15.3 0.56 -1.21	2270 423 0.38	10767 1261 0.89	/
	130 mg/m^3	49.3 2.7 1.93	15.5 0.27 -0.68	8133 242 -0.28	9500 1445 0.52	/
After 8 weeks	Control	/	/	7753 380	/	2.58 0.62
	Control (ethanol)	/	/	7460 535 -1.06	/	/
	13 mg/m^3	/	/	7810 460 0.23	/	/
	40 mg/m^3	/	/	8013 373 1.19	/	/
	130 mg/m^3	/	/	7670 259 -0.44	/	1.97 0.30 -2.20

Statistically significant from control at : 95 % (+ or -), 99 % ( ++ or --), 99.9 % (+++ or ---)

Table 2: Chemical biochemistry results

Groups	Na mEq/l	K mEq/l	Urea g/l	Bilirubin mg/l	Proteins g/l	alkaline phosphatase	alanine aminotransferase
Control	147.0 2.2	6.1 0.8	0.44 0.10	0.47 0.28	61.7 4.0	331 89	94* 62
Control (ethanol)	147.0 2.0	6.0 0.6	0.45 0.17	0.34 0.23	61.2 1.2	346 36	58 18
13 mg/m^3	147.6 2.2	5.4 0.3	0.40 0.12	0.80 0.30	59.0 4.3	322 91	50 7
40 mg/m^3	148.5 2.1	6.2 0.4	0.42 0.07	0.81 0.13	56.0 7.1	301 27	104* 151
130 mg/m^3	149.0 4.1	5.6 0.4	0.46 0.07	0.97 1.34	56.6 4.2	296 31	70 44

* Elevated medium due to an outlier.

Applicant's summary and conclusion

Conclusions:

Under the conditions of this test, the test substance showed a toxic effect at the blood cell level.

Executive summary:

Male and female rats were exposed to the test substance for 4 hours per day, 6 days per week during 4 weeks. Following the exposure, a rest period of 4 weeks was performed. Hematology examinations were performed at 2, 4, 6 and 8 weeks. Clinical Biochemistry examinations were performed at the end of the exposure (4 weeks). Histology and necropsy were also performed at the end of the exposure. Animals were exposed at 13, 40 or 130 mg/m³ of the test substance. No mortality related to test substance was observed and no clinical signs were reported. One female died due to an anesthesic accident. After 2 weeks of treatment, no effect was observed in all animals. At the end of the exposure (4 weeks), a slight decrease in the erythrocytes count and a significant decrease of leucocytes count at the highest tested doses were observed. In addition, the methemoglobin increased at 40 mg/m³ (3.3 %) and became anormal at the highest tested dose (4.5 %). After two weeks of rest, all parameters showed comparable values to controls. No significant effect on clinical biochemistry parameters (sodium, potassium, urea, total protein, alkaline phosphatase and alanine aminotransferase) was observed. No gross pathologic effect has been observed. An effect of the test substance on the spleen was observed. The number of foci of extramedullary hematopoiesis were increased in the red pulpe of the spleen and were accompanied by an increase of splenic hemosiderin and venous sinus congestion. After 4 weeks of rest, foci of hematopoiesis have decreased in all animals. Only clusters of hemosiderin in macrophages were persistant. Under the conditions of this test, the test substance showed a toxic effect at the blood cell level.