Subject to the provisions of Regulation 7 of these Regulations, where the content of an undesirable substance or product mentioned in column (1) of Part I of the Second Schedule to these Regulations in a feed material mentioned in column (2) of the said Part I exceeds the level laid down in column (3) of the First Schedule to these Regulations in respect of the corresponding feedingstuffs, the feed material mentioned in column (2) of Part I of the said Schedule, may be put into circulation only