1,4-Dichloro-2-nitrobenzene

1,4-ジクロロ-2-ニトロベンゼン

CAS No. 89-61-2

2,5-Dichloronitrobenzene

2,5-ジクロロニトロベンゼン

Molecular formula: C6H3Cl2NO2 Molecular weight: 192.00

ABSTRACT

With regard to reproductive/developmental toxicity, yellowish brown urine and salivation were found in both sexes at 60 and 200 mg/kg, and perigenital soiling, decrease in locomotor activity, extension of hindlimbs etc. were found in both sexes at 200 mg/kg. Death of one dam occurred during the gestation period, one during the delivery period and four during the lactation period in the 200 mg/kg group. Reduced body weight gains were found in both sexes at 200 mg/kg. On histopathological examination, degeneration of seminiferous epithelium in the testes and debris in epididymides ducts were found in the 200 mg/kg group. In addition, there were indications that the test substance affected growth of newborn pups at 200 mg/kg. The test substance is concluded to affect dams during the perinatal period and neonatal development in spite of no changes in copulation or fertility indexes. NOELs are suggested to be 200 mg/kg and 20 mg/kg for reproductive performance of males and females, respectively, and 60 mg/kg for development of pups in terms of reproductive developmental toxicological effects.

1,4-Dichloro-2-nitrobenzene was mutagenic in Salmonella typhimurium TA 100 with and without metabolic activation and TA1537 without metabolic activation. Structural chromosomal aberrations were induced at the highest concentration (0.15 mg/ml) with 48-hr continuous treatment of CHL/IU cells. Polyploid cells were not induced.

SUMMARIZED DATA FROM THE STUDIES

1. Preliminary Reproductive/Developmental Toxicity1)

Purity	:	>99.5%
Test species/strain	:	Rat/Crj:CD (SD)
Test method	:	OECD Preliminary Reproduction Toxicity Screening Test
Route	:	Oral (gavage)
Dosage	:	0 (Vehicle), 6, 20, 60, 200 mg/kg/day
Number of animals	:	Males, 12; Females, 12/group
Vehicle	:	Corn oil
Administration period	:	Males, 49 days Females, from 14 days before mating to Day 3 of lactation
Terminal killing	:	Males, Day 50 of administration Females, Day 4 of lactation
GLP	:	Yes

　Test results:

<Reproductive/Developmental Toxicity>

One dam receiving 60 mg/kg delivered only dead pups. In the 200 mg/kg group, one dam died on Day 20 of pregnancy, one during the delivery period and four during the lactation period. Lack of care behavior was also found in seven dams receiving 200 mg/kg. A lower value for the viability index on Day 4 of lactation was obtained with 200 mg/kg because many pups died during the lactation period. With the pups of the 200 mg/kg group, reduced body weight values were obtained for both sexes on Days 0 and 4 of lactation. It is concluded that this test substance exerts effects on dams during the perinatal period at 60 mg/kg or more and the dams during the lactation period at 200 mg/kg. In addition, there are indications that the test substance affects growth of newborn pups at 200 mg/kg. NOELs are concluded to be 200 mg/kg and 20 mg/kg for reproductive performance of males and females, respectively, and 60 mg/kg for development of pups in terms of reproductive developmental toxicological effects.

<Repeat Dose Toxicity>

This test substance exhibited influence on general signs (yellowish brown urine and salivation at 60 mg/kg or more, and perigenital soiling, decrease in locomotor activity and extension of hindlimbs at 200 mg/kg in both sexes), suppressed body weight gains in both sexes at 200 mg/kg, lower values for food consumption in females at 200 mg/kg. Degeneration of seminiferous epithelium in the testes and debris in ducts of the epididymides were found at 200 mg/kg. Atrophy of the thymus and decreased cellularity of white pulp in the spleen were found in surviving females, whereas atrophy/hemorrhage in the thymus, lymphoid atrophy and decreased cellularity of marginal zone in the spleen, congestion in the lungs and liver, and glandular stomach were ulcer at on found in females receiving 200 mg/kg which died.

2. Genetic Toxicity

2-1 Bacterial test2)

Purity	:	above 99.5%
Test species/strain	:	S.typhimurim TA100, TA1535, TA98, TA1537 E. coli WP2 uvrA
Test method	:	Guidelines for Screening mutagenicity Testing of Chemicals (Japan)
Procedures	:	Plate incorporation method
Solvent	:	DMSO
Positive controls	:	-S9 Mix, AF-2 (TA100, WP2, TA98) sodium azide (TA1535) and 9-aminoacridine (TA1537) +S9 Mix; 2-aminoanthracene (all strains)
Doses	:	- S9 Mix; 0, 78.13 - 2500 μg/plate (TA100) +S9 Mix; 78.13 - 2500 [156.3 - 5000 (WP2 and TA1537)] 0, 156.3, 312.5, 625, 1250, 2500 and 5000 (WP2)
S-9	:	Rat liver, induced with phenobarbital and 5,6-benzoflavone
Plates/test	:	3
Number of replicates	:	2
GLP	:	Yes

　Test results:

Minimum concentration of test substance at which toxicity was observed:

Toxicity was observed at concentrations of 1250 (TA1535 and TA1537), 2500 (TA100) and 5000 (TA98) μg/plate with out metabolic activation and 1250 (TAl535, TA98 and TA1537) and 2500 (TA100 and WP2) μg/plate with metabolic activation.

　Genetic effects :

S. typhimurium TA100

	+	?	-
without metabolic activation:	[*]	[ ]	[ ]
with metabolic activation:	[*]	[ ]	[ ]

S. typhimurium TA1535

	+	?	-
without metabolic activation:	[*]	[ ]	[ ]
with metabolic activation:	[ ]	[ ]	[*]

S. typhimurium TA 98 and TA1537

	+	?	-
without metabolic activation:	[ ]	[ ]	[*]
with metabolic activation:	[ ]	[ ]	[*]

E. Coli WP2 uvrA

	+	?	-
without metabolic activation:	[ ]	[ ]	[*]
with metabolic activation:	[ ]	[ ]	[*]

2-2. Non-bacterial in vitro test (chromosomal aberration test)2)

Purity	:	More than 99.5%
Type of cell used	:	Chinese hamster lung (CHL/IU) cells
Test method	:	Guidelines for Screening Mutagenicity Testing of Chemicals (Japan)
Solvent	:	Dimethyl sulfoxide
Positive controls	:	-S9, Mitomycin C +S9, Cyclophosphamide
Doses	:	-S9 (continuous treatment): 0, 0.04, 0.08, 0.15 mg/ml -S9 (short-term treatment): 0, 0.024, 0.047, 0.094 mg/ml +S9 (short-term treatment): 0, 0.024, 0.047, 0.094 mg/ml
S-9	:	Rat liver, induced with phenobarbital and 5,6-benzoflavone
Plates/test	:	2
GLP	:	Yes

　Test results:

Cytogenetic effects were seen as follows.

At the highest concentration (0.15 mg/ml) after 48-hr continuous treatment without metabolic activation, 10.6% cells demonstrated structural chromosomal aberrations, including gaps.

Lowest concentration producing cytogenetic effects in vitro:

without metabolic activation (continuous treatment ): 0.15 mg/ml (clastogenicity)

　Genotoxic effects:

	clastogenicity			polyploidy
	+	?	-	+	?	-
without metabolic activation:	[*]	[ ]	[ ]	[ ]	[ ]	[*]
with metabolic activation:	[ ]	[ ]	[*]	[ ]	[ ]	[*]

1)	The test was performed by Nihon Bioresearch Inc. Hashima Laboratory, 6-104 Majima, Fukuju-cho, Hashima, Gifu, 501-62 Japan Tel +81-58-392-6222 Fax +81-58-391-3171
2)	The tests were performed by the Hatano Research Institute, Food and Drug Safety Center, 729-5 Ochiai, Hadano-shi, Kanagawa, 257, Japan. Tel +81-463-82-4751 Fax +81-463-82-9627