Defences which may or may not be allowed in prosecutions under this Act.—
1) Save as hereinafter provided in this section, it shall be no defence in a prosecution under this Act to prove merely that the accused was ignorant of the nature or quality of the insecticide in respect of which the offence was committed or of the risk involved in the manufacture, sale or use of such insecticide or of the Section 1 - circumstances of its manufacture or import