4.—(1) Subject to paragraph (2) of this regulation, no person shall sell, consign or deliver—
(a)any oil or fat or any mixture thereof, if erucic acid constitutes more than five per centum of its fatty acid content; or
(b)any food to which oil or fat or a mixture thereof has been added, if erucic acid constitutes more than five per centum of the fatty acid content of all the oil and fat in the food.
(2) In relation to any oil, fat or food manufactured before 1st July 1979, these regulations shall have effect as if the percentages specified in paragraph (1)(a) and (b) of this regulation were in each case ten instead of five.