Tridemorph

Chemical name (IUPAC):

4-alkyl-2,6-dimethylmorpholine; for original definition, 2,6-dimethyl-4-tridecyl= morpholine

A fungicide used to control the fungus Erysiphe graminis in cereals and a range of other diseases.

It is also used with a number of other fungicides including: cyproconazole, fenbuconazole, fenpropi-morph, flusilazole, propiconazole, tebucon-azole, triadimenol.

Tridemorph is applied onto many crops across the world, but very little data on usage and production is in the public domain. It was developed in the 1960s by the German multinational BASF who sell tridemorph under the trade name Calixin. In Europe, it is used in Austria, Belgium, Finland, Germany, Greece, Italy, Ireland, Luxembourg, Netherlands, Spain and UK. It is applied widely on banana plantations Latin America, especially Costa Rica and Ecuador.
    In the UK there are 29 approved products, predominately for use against powdery mildew on cereals but also on root crops. There are no home garden products. In 1997, tridemorph was most commonly used on winter barley (61,207 kg) followed by wheat (50,588 kg) and spring barley (18,411 kg).

Acute toxicity

The acute oral LD50 (the dose required to kill half a population of laboratory test animals) for tridemorph is 650 mg/kg for rats. It is classified by the World Health Organisation as Class II a 'moderately hazardous' pesticide. It is harmful if swallowed and irritating to eyes and skin. Tests show it is moderately to severely irritating to rabbit skin and rabbit eyes. Prolonged or repeated exposure may cause dermatitis and/or conjunctivitis. Inhalation of tridemorph vapour may cause adverse health effects (specific effects not stated). Laboratory rats survived an 8 hour exposure to air saturated with tridemorph vapour.