Anisidine

The anisidines encompass the three possible isomers of aminoanisole, a benzene ring substituted with a methoxy group and an amino group. These are 2-anisidine (o-anisidine), 3-anisidine (m-anisidine) and 4-anisidine (p-anisidine). All isomers are toxic. They are used as intermediaries in the production of azo-dyes and pharmaceuticals.

2-Anisidine
2-Anisidine (CAS-No. 90-04-0, EU-No. 201-963-1, UN-No. 2431) is a yellow liquid with melting point -1 to 5 °C and density 1.09 g/cm³. The vapor pressure is 0.05 mbar at 20 °C but increases greatly with temperature. It has an aromatic smell and is well absorbed by inhalation, oral ingestion and skin contact. 2-Anisidine is a very toxic agent that causes blood, enzyme and nerve damage with cyanosis and the danger of suffocation. The agent is an experimental carcinogen and is strongly suspected to be also a human carcinogen. The common exposure limit (workplace) is 0.1ml/m3 (=0.5mg/m3). 2-Anisidine has dangerous pollutant properties for water.

3-Anisidine
3-Anisidine (CAS-No. 536-90-3, UN-No. 2431) is a liquid with melting point -1 to 1 °C. The densitity is 1.101 g/cm³. It is very poisonous for the blood leading to pink coloration of the skin and inner suffocation. Additionally its vapors are irritanting to eyes, mucous membranes, the respiratory system and skin. It is not a carcinogen. Exposure limits are the same as for 2-anisidine.

4-Anisidine
4-Anisidine (CAS-No. 104-94-9, UN-No. 2431) is a greybrown solid with melting point 57 to 60 °C. It is the least toxic of the three isomeres (oral LD50 = 1,400mg/kg) but still causes blood damages upon oral ingestion, inhalation or skin contact. If heated strongly, it may release very toxic fumes of nitrogen oxides.