Toxicity
The seeds resemble the seeds of Brassica nigra (mustard). As a result, mustard can be adulterated by argemone seeds, rendering it poisonous. Several significant instances of katkar poisoning have been reported in India, Fiji, South Africa and other countries. The last major outbreak in India occurred in 1998. 1% adulteration of mustard oil by argemone oil has been shown to cause clinical disease.
Katkar oil poisoning causes epidemic dropsy, with symptoms including extreme swelling, particularly of the legs.
Read more about this topic: Argemone Mexicana