1-chloro-4-nitrobenzene

Endpoint summary

Description of key information

P-chloronitrobenzene was found to be harmful if swallowed, in contact with skin and by inhalation.

Key value for chemical safety assessment

Acute toxicity: via oral route

Endpoint conclusion

Dose descriptor:

LD50

Value:

294 mg/kg bw

Acute toxicity: via inhalation route

Endpoint conclusion

Dose descriptor:

discriminating conc.

Value:

16 100 mg/m³

Acute toxicity: via dermal route

Endpoint conclusion

Dose descriptor:

LD50

Value:

750 mg/kg bw

Additional information

p-chloronitrobenzene is toxic by oral administration, dermal contact and by inhalation.

The acute oral toxicity of 1 -chloro-4 -nitrobenzene was investigated in male Wistar II rats in a study comparable to OECD

guideline 401 with acceptable restrictions. 7 male groups of 10 animals were dosed with 100, 200, 300, 350, 400, 500 and 600 mg/kg bw 1-chloro-4-nitrobenzene per gavage and observed for 14 days following exposure for mortality and clinical signs. Mortalities occurred at dose levels equal to and exceeding 200 mg/kg bw 2 days after administration. Reduced general condition, cyanotic appearance, diarrhea, increased excretion of urine were observed in all male animals dosed 200 - 600 mg/kg bw. Symptoms started to appear between 3 hours (600 mg/kg bw) and 4 days (400 and 600 mg/kg bw) after administration. No clinical signs were observed in animals dosed with 100 mg/kg bw in male rats. The calculated LD50 for male rats was 294 mg/kg bw.

The dermal LD50 ranges for rats are between 750 - 1722 mg/kg body weight and the ranges in rabbit studies are between 2000 - 3160 mg/kg bw.

In a study performed comparable to guideline study 402 with acceptable restrictions the acute dermal toxicity of 1 -chloro-4 -nitrobenzene was investigated in male rats. The LD50 was 750 mg/kg body weight (Loeser, Bayer AG, 1979).

The acute inhalative toxicity of 1 -chloro-4 -nitrobenzene was investigated in study comparable to OECD guideline 403 with acceptable restrictions. Rats were exposed head-only to an atmosphere containing vapour and microcrystalline particles up to 16,100 mg/m³ air for 4 hours. Clinical signs of toxicity were related to dose. During and immediately after exposure cyanosis, corneal opacity, abnormal arched-back posture, lethargy, reddish-brown nasal and frothy mouth discharges, tachypnea, semi-prostration were observed. From 1 - 14 days post exposure pallor, lacrimation, alopecia, corneal opacity, stained perineal area, dermal irritations were observed. Aslo weight loss of 6 - 13 % was detected within the first 24 hours but weight gain normailzed therafter. Three days post exposure death occured at 16100 mg/m³ in 1 of 10 animals. Therefore the LCLo was 16100 mg/m³air (Dupont, 1981).

Justification for classification or non-classification

Based on the available study results, the following classification is derived; this deviates from the present legal classification (see Section 2):

LD50(oral) = 294 mg/kg bw

Classification:

DSD: Xn, R22 Harmful if swallowed

GHS: Acute Oral Category 3 H301

LD50(dermal) = 750 mg/kg bw

Classification:

DSD: Xn, R21 Harmful in contact with skin

GHS: Acute Dermal Category 3 H311

LCLo (inhalation) = 16100 mg/m³ air

Classification:

DSD: Xn, R20 Harmful by inhalation

GHS: Acute Inhalation Category 3 H331