Plant growth regulators in cereals 1992-2017 – a trend analysis

One of the responsibilities of the Swedish  Food Agency (SLV) is to secure safe food for Swedish consumers. To ensure this the SLV has a control programme for pesticide residues in food products.
Before 1992 the SLV had no analytical methods for analysis of plant growth regulator residues. This report includes data from 1992, i.e. from the year when it was possible to analyse chlormequat/ mepiquat. Since then it has been possible to analyse residues of trinexapac and ethephon as well. In Swedish rye the most commonly found plant growth regulator is chlormequat, but residues of mepiquat are also detected regularly. The residue levels of mepiquat is often slightly lower than the residues of chlormequat, but all residue levels found between 1992 and 2017 are well below the maximum residue limit. During recent years trinexapac and ethephon have also been detected in the control. These findings have been far below the maximum residue limits.
Results from analysis of Swedish wheat, barley and oats have also been studied. No trace of plant growth regulators has been found in barley and oats, but in most years residues of plant growth regulators have been detected in wheat. The most commonly detected plant growth regulator is chlormequat in wheat as well; the second most common is trinexapac. Mepiquat has also been detected a few times in Swedish wheat during the 25 years studied, but not ethephon. The residue levels of plant growth regulators in wheat were all far below the maximum residue limit.
The same substances of plant growth regulators as those detected in Swedish cereals have been detected in cereals imported from other EU member states to Sweden. The residue levels were slightly lower in Swedish cereals, but all residues were well below the maximum residue level. It is not possible to detect any clear trend in the residue data, other than that more substances are used today than during the 1990s.
The SLV performed a cumulative risk assessment based on how much cereals Swedish consumers, adults and children, normally eat and residue levels of plant growth regulators found in the control programme. Based on today’s knowledge the consumer risk assessment indicates that detected residue levels of plant growth regulators in cereals available on the Swedish market do not cause a health risk to consumers, neither to adults nor children, and it does not matter whether the consumer eat Swedish or imported cereals.

Link to report

Note: this report is published by the Swedish Food Agency as part of their SLV-Report Series (ISSN: 1104-7089)