3-nitrotoluene

Endpoint summary

Description of key information

Acute tox values: 
oral 
LD50 = 2121 mg/kg bw male
LD50 = 1784 mg/kg bw female
Inhalative: LD50= 880 mg/m³
Dermal: LD50 > 1157 mg/kg bw

Additional information

With a single oral administration to rats, the following symptoms occurred at doses of 500 mg/kg bw and above: sedation, cyanosis, impairment of the general condition and patchy livers in animals found dead [Gröning et al. 1976.Bayer AG. Unpublished report]. Doses ranging from 1000 to 4000 mg/kg bw also caused excitation, increased breathing frequency, short-term convulsions, debility and atony [Ciss et al., 1980. Dakar Medical 25:303-311; Ciss et al., 1978. Dissertation. Unversite´ Rene´Descartes de Paris, Serie E No. 17].

In rats of both sexes a single dermal application of 1157 mg m-nitrotoluene/kg bw (exposure time: 24 hours) caused an impairment of general condition; no deaths occurred [Gröning et al. 1976.Bayer AG. Unpublished report]. A rabbit weighing 2.175 kg, treated with a single dermal application of 1 mL m-nitrotoluene (532 mg/kg bw) to the skin of the back, flanks and belly, exhibited a slightly increased breathing rate. The animal behaved normally during the 50-hour exposure period [Dambleff J: Beiträge zur Kenntnis der giftigen Wirkung nitrierter Benzole und Toluole insbesonder von der Haut aus. Dissertation, Würzburg, 1908].

A 1-hour inhalation of m-nitrotoluene vapour (calculated concentration: 2417 mg/m³) was tolerated without symptoms by male rats and mice [Gröning et al. 1976.Bayer AG.Unpublished report].

Study on Methemoglobin formation: Two cats received a single intra peritoneal injection of 100 mg m-nitroroluene/ kg bw, maximum methemoglobin levels ranging from 9 to 52% were reached after 4 to 8 hours; the values differed greatly between individual animals and no dose dependency was seen. More Heinz bodies were also detected that with o-nitrotoluene. All the treated animals displayed reduced blood-clotting ability. At doses of 300 mg/kg bw and above, the following effects were observed: cramps in the extremities, trembling, baring of the teeth, breathing disorders, dilation of pupils, rigidity of the entire musculature on the day of administration and muscular laxity on the following day [Von Bredow et al., Naunyn-Schmiedeberg´s Arch. Exp. Path. Pharmak. 200, 335-355. 1942-1943].

Justification for classification or non-classification

Like other nitrotoluenes, a primary toxic effect of 3 -nitrotoluene is methaemoglobin formation. Taking into account that humans are much more sensitive to methaemoglobin producing substances than rats it is suggested to classify 3-nitrotoluene as T; R 23/24/25 , according to DSD-DPD and Toxicity Category III according to EU-GHS.