1,2-dichloro-3-nitrobenzene

Repeated dose toxicity: oral

Administrative data

Endpoint:

short-term repeated dose toxicity: oral

Remarks:

combined repeated dose and reproduction / developmental screening

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Acceptable, well-documented study publication which meets basic scientific principles.

Data source

Reference

Reference Type:

publication

Title:

Unnamed

Year:

1994

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 422 (Combined Repeated Dose Toxicity Study with the Reproduction / Developmental Toxicity Screening Test)

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

1,2-dichloro-3-nitrobenzene

EC Number:

221-717-7

EC Name:

1,2-dichloro-3-nitrobenzene

Cas Number:

3209-22-1

Molecular formula:

C6H3Cl2NO2

IUPAC Name:

1,2-dichloro-3-nitrobenzene

Details on test material:

test substance purity: 99.15%

Test animals

Species:

rat

Strain:

Crj: CD(SD)

Sex:

male/female

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

olive oil

Details on oral exposure:

admnistration period: male 44 days, females from day 14 before mating to day 3 of lactation.

Duration of treatment / exposure:

admnistration period: male 44 days, females from day 14 before mating to day 3 of lactation; terminal kill: male day 45; females: day 4 of lactation.

Frequency of treatment:

daily

Doses / concentrations

Remarks:

Doses / Concentrations:
0, 1, 5, 100 mg/kg bw
Basis:

No. of animals per sex per dose:

five per dose and sex

Control animals:

yes, concurrent vehicle

Results and discussion

Results of examinations

Details on results:

1,2-dichloro-3-nitrobenze induced toxic effects in liver and kidney and induced hemolytic anemia in treated rats. Liver and kidney weights were increased and splenic hemosiderosis occured. Hepatocellular swelling and hyaline droplets in the renal convoluted tubular epithelium were observed in males given 25 mg/kg or more. Elevations in urine protein, serum Na, total protein and total cholesterol, and decreases in blood urea nitrogen and body weight gain were noted in males given 100 mg/kg. The females given 25 mg/kg or more exhibited similar pathological changes in the liver, kidney and spleen. The change in the kidney was characterized by vacuolated tubular epithelium.

Effect levels

1

Dose descriptor:

NOAEL

Effect level:

5 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: no adverse effects

2

Dose descriptor:

LOAEL

Effect level:

25 mg/kg bw/day (nominal)

Based on:

test mat.

Sex:

male/female

Basis for effect level:

other: males and females: decreased body weights, increased liver and kidney weights, hepatocellular swelling, hemosiderosis (males), hyaline droplets in proximal tubular epithelium (males), vacuolated tubular epithelium of the kidney (females)

Target system / organ toxicity

Critical effects observed:

not specified

Any other information on results incl. tables

The parental males receiving doses of 1 or 5 mg/kg exhibited no effects related to the test substance. In the 25 mg/kg dose group, liver and kidney weights were increased, and splenic hemosiderosis occurred. Histologically, hepatocellular swelling and hyaline droplets in the renal convoluted tubular epithelium were observed. In addition, to these changes, overt regeneration was found in the renal tubules of the 100 mg/kg dose group. Elevations of urine protein, serum sodium, total protein and total cholesterol, and decreases of blood urea nitrogen and body weight gain were found. Hemolytic anemia was revealed in the 100 mg/kg dose group as indicated by decrease of hemoglobin and hematocrit values, and increased reticulocyte counts. Parental females also exhibited pathological changes in the liver, kidney and spleen at doses of 25 mg/kg or more. The change in female kidneys was characterized by vacuolated tubular epithelium. Incidence of athropic thymus was increased in the 100 mg/kg dose group when compared with the control group. There were no notable alterations in general conditions, and no fatalities among any of the dosage groups. Food consumption of the 100 mg/kg males and females was decreased on the first day of the treatment but showed no significant difference from control values thereafter. NOAEL: 5 mg/kg/day.

 

 

Table: absolute and relative organ weights of parental male and female rats

Sex	Dose (mg/kg)	0	1	5	25	100
Males	Number of animals	10	10	10	10	10
	Final body weight (g)	543 ± 43	506 ± 15	515  ± 24	496 ± 28*	481 ± 31**
	Liver (g)	17.76 ± 2.88	16.23 ± 1.34	17.00± 2.02	19.71 ± 2.35	21.64 ± 2.27**
	Liver (g%)	3.30  ±0.30	3.21 ± 0.23	3.36 ± 0.27	3.96 ± 0.29**	4.49 ± 0.26**
	kidneys (g)	3.54  ± 0.34	3.35 ± 0.22	3.49 ± 0.26	3.75 ± 0.42	4.11 ± 0.51**
	kidneys (g%)	0.66  ± 0.07	0.66 ± 0.05	0.69 ± 0.07	0.76 ± 0.08*	0.85 ± 0.10**
	Thymus (g)	0.41  ± 0.11	0.44 ± 0.07	0.37 ± 0.07	0.38 ± 0.06	0.38 ± 0.10
	Thymus (g%)	0.08±0.02	0.09± 0.01	0.07±0.01	0.08± 0.01	0.08±0.02
	Testes (g)	3.28 ± 0.23	3.30± 0.17	3.40±0.24	3.47± 0.29	3.39±0.32
	Testes (g%)	0.62±0.07	0.65± 0.03	0.68±0.06	0.70± 0.08*	0.70±0.05**
	Epididymides (g)	1.33±0.09	1.35± 0.07	1.35±0.07	1.35±  0.11	1.37±0.12
	Epididymides (g%)	0.25 ±0.03	0.27± 0.01	0.27±0.02	0.27± 0.03	0.29±0.03**
Females	Number of animals	8	7	9	8	8
	Final body weight (g)	348  ± 30	355 ± 31	360 ± 21	354 ± 12	342 ±20
	Liver (g)	13.86 ± 0.80	15.00± 1.11	15.30±0.62	17.27± 0.65*	20.52±2.24**
	Liver (g%)	4.00  ± 0.22	4.23 ± 0.31	4.26  ±0.18	4.89± 0.10	5.99±0.42**
	Kidneys (g)	2.00  ± 0.11	2.20± 0.20	2.19±0.25	2.30± 0.25	2.46±0.19**
	Kidneys (g%)	0.58  ±0.03	0.62±0.04	0.61±0.06	0.65± 0.06	0.72± 0.06**
	Thymus (g%)	0.07  ±0.03	0.06± 0.02	0.08±0.02	0.06± 0.01	0.04±0.02
	Thymus (g)	0.24±0.12	0.20± 0.07	0.28±0.09	0.20± 0.04	0.15±0.05

 

* significantly different from control at 5% level of probability

 

** significantly different from control at 1% level of probability

 

Table: Incidence of histopathological findings in parental male rats

Males	Findings
	Dose		0	1	5	25	100
Organ	Animals examined		10	10	10	10	10
Liver	Hepatocellular swelling	+	0	0	0	7	7
	Hepatocellular swelling	++	0	0	0	0	3
	Total		0	0	0	7**	10**
	Hepatocellullar fatty change	+	3	1	0	0	0
	Focal necrosis	+	0	0	0	0	0
Kidneys	Hyaline droplets in proximal tubular epithelium	+	0	0	0	4	0
	Hyaline droplets in proximal tubular epithelium	++	0	0	0	3	9
	Hyaline droplets in proximal tubular epithelium	+++	0	0	0	0	1
	Total		0	0	0	7**	10**
	Eosinophilic bodies in proximal tubule	+	3	3	2	2	4
	Eosinophilic bodies in proximal tubule	++	2	1	1	4	1
		+++	0	0	0	0	1
	Total		5	4	3	6	6
	Tubular casts	+	0	0	0	0	2
	Tubular atrophy and regeneration	+	2	0	0	4	4
	Tubular atrophy and regeneration	++	0	0	0	0	3
	Tubular atrophy and regeneration	+++	0	0	0	0	1
	Total		0	0	0	4	8**
	Fibrotic foci	+	0	0	0	0	0
	Tubular mineralization	+	0	0	0	0	0
Spleen	Increased extramedullary hematopoiesis	+	0	0	0	0	2
	Hemosiderosis	+	0	0	0	4*	8**

 

 

 

Table: Incidence of histopathological findings in parental female rats

females	Findings
	Dose		0	1	5	25	100
Organ	Animals examined		10	10	10	10	10
Liver	Hepatocellular swelling	+	0	0	0	10	0
	Hepatocellular swelling	++	0	0	0	0	10
	Total		0	0	0	10**	10**
	Hepatocellullar fatty change	+	0	0	0	0	0
	Focal necrosis	+	0	0	0	0	1
Kidneys	Tubular epithelial vacuolation	+	0	0	0	1	3
	Tubular epithelial vacuolation	++	0	0	0	1	3
	Tubular epithelial vacuolation	+++	0	0	0	0	1
	Total		0	0	0	2	7**
	Tubular atrophy and regeneration	+	0	0	1	0	1
	Tubular atrophy and regeneration	++	0	0	0	0	0
	Tubular atrophy and regeneration		0	0	0	0	0
	Total		0	0	1	0	1
	Fibrotic foci	+	0	1	0	0	0
	Tubular mineralization	+	1	0	0	0	0
Spleen	Hemosiderosis	+	0	0	0	1	5**

* significantly different from control at 5% level of probability ** significantly different from control at 1% level of probability

 

* significantly different from control at 5% level of probability

 

** significantly different from control at 1% level of probability

Applicant's summary and conclusion

Executive summary:

In a repeated dose and reproductive/developmental toxicity Screening Test (OECD TG 422) 1,2-dichloro-3-nitrobenzene was administered (oral gavage) to male and female Crj:CD (SD) rats. The rats were treated with 0 (vehicle)1, 5, 25 and 100 mg/kg bw/day test substance. The parental males receiving doses of 1 or 5 mg/kg exhibited no effects related to the test substance. In the 25 mg/kg dose group, liver and kidney weights were increased, and splenic hemosiderosis occurred. Histologically, hepatocellular swelling and hyaline droplets in the renal convoluted tubular epithelium were observed. In addition, to these changes, overt regeneration was found in the renal tubules of the 100 mg/kg dose group. Elevations of urine protein, serum sodium, total protein and total cholesterol, and decreases of blood urea nitrogen and body weight gain were found. Hemolytic anemia was revealed in the 100 mg/kg dose group as indicated by decrease of hemoglobin and hematocrit values, and increased reticulocyte counts. Parental females also exhibited pathological changes in the liver, kidney and spleen at doses of 25 mg/kg or more. The change in female kidneys was characterized by vacuolated tubular epithelium. Incidence of atrophic thymus was increased in the 100 mg/kg dose group when compared with the control group. There were no notable alterations in general conditions, and no fatalities among any of the dosage groups. Food consumption of the 100 mg/kg males and females was decreased on the first day of the treatment but showed no significant difference from control values thereafter.

Based on these findings the authors suggested a NOAEL of 5 mg/kg bw/day (Ministry of Health and Welfare Japan 1994).