Residues of Straw Height Reducing Plant Growth Regulators in Cereal Products

Abstract: The use of plant growth regulators (PGRs) to reduce stem elongation in cereals has for a long time been debated in Sweden, particularly since residues of especially one active substance, chlormequat, are often detected in cereal food products. The food company Coop Sverige AB has a desire to limit the possible presence of PGRs in the cereal products of their own brands. Therefore in this thesis, products were sent to Eurofins for analysis of the active substances chlormequat, ethephon, mepiquat and trinexapac. Also, a literature review has been made to investigate how the substances are regulated nationally and in the European Union, the presence in plant protection products (PPPs) in Sweden and the effect on human health. Additionally, a brief analysis on the attitude towards the PGRs in the Swedish cereal industry was made. Residues of the substances were found in 12 out of 23 products. The most frequently detected substance was chlormequat, in the range of 0.006-0.15 mg/kg. Trinexapac and mepiquat were found in two samples respectively. No residue of ethephon was found in any sample. All cereals deriving from Germany contained residues, while the majority of the products originating from Sweden and Italy were free from residues. Since all values were below the corresponding maximum residue levels (MRLs), the residues in the analysed food poses no risk to the consumer.