PESTICIDE USAGE SURVEY REPORT 275 POTATO STORES IN THE UNITED KINGDOM 2016 A. Hinchcliffe, I. Barker, D. G. Garthwaite & G. Parrish Pesticide Usage Survey Team Fera Sand Hutton York UK YO41 1LZ A NATIONAL STATISTICS SURVEY National Statistics are produced to high professional standards set out in the Code of Practice for Official Statistics. They are free from any political interference. The UK Statistics Authority has a statutory duty to assess National Statistics for compliance with this Code of Practice. Further information is available from the Office for National Statistics website (http://www.ons.gov.uk/ons/index.html). The statistics undergo regular quality assurance reviews to ensure that they meet customers’ needs. The United Kingdom Statistics Authority has designated these statistics as National Statistics, in accordance with the Statistics and Registration Service Act 2007 and signifying compliance with the Code of Practice for Official Statistics. Designation can be broadly interpreted to mean that the statistics: • meet identified user needs; • are well explained and readily accessible; • are produced according to sound methods; and • are managed impartially and objectively in the public interest. Once statistics have been designated as National Statistics it is a statutory requirement that the Code of Practice shall continue to be observed. If you have any enquiries or feedback on the statistics included in this report they can be directed to the contact given below: Pesticide Usage Survey Team – e-mail: [email protected] Telephone: 01904 462 302 Alternatively, please contact: Fera Science Ltd. at: [email protected] DATA USES The data are used for several purposes including: • Quantifying pesticide usage and changes in the use of active substances over time; • Policy, including assessing the economic and/or environmental implications of the introduction of new active substances and the withdrawal/non-authorisation of pesticide products (the data reported to organisations such as the OECD and EU enabling the UK to honour international agreements); evaluating changes in growing methods and Integrated Pest Management where this has an impact on pesticide usage; • Informing the pesticide risk assessment (authorisation) process; • Informing the targeting of monitoring programmes for residues in food and the environment; • Contributing to assessing the impact of pesticide use, principally as part of the Pesticides Forum’s Annual Report; • Responding to enquiries (for example, Parliamentary Questions, correspondence, queries under the Freedom of Information Act or Environmental Information Regulations, etc.); • Providing information to assist research projects which can support all the above activities; • Training/teaching programmes which are designed to improve practice in the use of pesticides by the farming/training industries; • Informing the Wildlife Incident Investigation Scheme (WIIS) programme to help identify potential misuse of pesticides. REVISIONS POLICY This report presents a comprehensive summary of data for Potatoes harvested in 2016 and stored during 2016/2017. We will provide information on any revisions we make to the report or the datasets if any inaccuracies or errors occur. Details of any revisions, including the date upon which they were changed, will appear on the following website: https://secure.fera.defra.gov.uk/pusstats/surveys/index.cfm 2 CONTENTS PAGE Executive Summary 4 Introduction 6 Trends 7 Ware Potatoes 9 Seed Potatoes 10 Appendix 1 – Ware Potato Tables 11 Appendix 2 – Seed Potato Tables 12 Appendix 3 – Comparison Table 13 Appendix 4 – Utilisation of Ware Potato Stores for Other Commodities 14 Appendix 5 – Definitions 15 Appendix 6 – Methodology 16 Acknowledgements 19 References 19 3 EXECUTIVE SUMMARY This report presents information on all aspects of pesticide usage during storage of potatoes harvested in 2016 and stored during 2016/2017. Data were collected by a combination of visits and telephone surveys comprising of 69 merchants stores and 72 farm stores totalling 141 stores surveyed in the United Kingdom. A total of 9.6% of the ware potato crop tonnage stored and 26% of the seed potato tonnage stored were surveyed in this year’s survey round. As for the 2014 report, the main body of the 2016 report differs from previous potato storage reports, in that the data collected on ware potatoes from both farm and merchant are now combined. This reflects the changes in potato storage practice over the last decade which has resulted in very little difference between the way in which farm and merchant stores are managed. In addition, data collection has changed from primarily a visit survey, to a combination of visit, postal and telephone surveys. Farm and merchant stores are still reported separately for the purposes of estimating the storage of other commodities and the use of chlorpropham where other commodities have been stored, as this would be expected to be more relevant to farm potato stores. The estimated weight of ware potatoes stored from the 2016 harvest was approximately 3.45 million tonnes, of which this survey estimated that 69% received no post-harvest treatment (79% of the untreated crop was in refrigerated stores). The basic tonnage treated was 1.07 million tonnes, though some potatoes received multiple treatments. The total tonnage treated, which adds up the tonnages of multiple treatments, was 1.64 million tonnes. The active substance chlorpropham, a potato sprout suppressant, accounted for 82% of the total tonnage treated, while 15% were treated with ethylene, 3% with spearmint oil, and less than 1% with either imazalil/thiabendazole or imazalil alone. A total of 9.2 tonnes of active substances were used to treat ware potatoes. Chlorpropham (95%), spearmint oil (4%), thiabendazole (<1%) and imazalil (<1%), accounted for the total weight of active substances used. Ethylene gas does not have a weight of active substance associated to it. Gro-Stop Electro was encountered for the first time in 2016, this formulation of chlorpropham contains eugenol (clove oil). From this survey, it is estimated that 46% of the 550,582 tonnes of the stored seed potatoes were treated, either on entry to the store or during the storage period, with a single application of pesticides. The formulations recorded were imazalil/thiabendazole, imazalil and ethylene, accounting for 84%, 15% and 1% of the total tonnage treated respectively. In total, 6.14 tonnes of active substances were used, principally thiabendazole, accounting for 65% of the total weight, and imazalil 35%. A comparison is made between this survey and previous surveys conducted between 2006 and 2016. The tonnage of ware potatoes stored increased by 11% from that in 2014 despite a decrease of 2% in the area grown, reflecting the favourable 2016 growing season. The basic tonnage treated decreased by 34% and the total tonnage treated decreased by 63% from that recorded in 2014. The 2016 season demonstrated a dramatic change. The weight of active substances used in 2016 was 9.2 tonnes, a decrease in usage of 75%. This marked reduction in usage could be explained by many cumulative factors. Growers and processors are increasingly concerned over acrylamide levels in the potato crop and the effects this has on potato quality, and so this is reflected by the proportion of untreated crop tonnage, increasing to 69% of the total ware tonnage stored in 2016. In addition, the total tonnage of ware potatoes treated in store decreased by 63% since 2014. The significant reduction in the weight of active substances used since 2014 also reflects the current requirement for store managers to adhere to the ‘Step Down’ process to which introduced lower application rates for chlorpropham during the 2016/17 season. In addition, Stewardship best practice (endorsed by the CIPC Applicator Group and Red Tractor Farm Assurance) continues to allow just a single application to chlorpropham up to a maximum of 16 gr/tonne in refrigerated stores. Changes from July 2017 introduced the requirement for ‘active recirculation’ during and after chlorpropham application to stored 4 potatoes which may have influenced store management during the 2016/17 season as store managers were encouraged to “Be 2017 Ready” The usage of imazalil and imazalil/thiabendazole on ware crops also fell significantly between 2014 and 2016 contributing a reduction in weight of active substance applied of 1.78 tonnes alone. The use of ethylene gas has no weight of active substances associated with it in 2016, whereas in 2014, some stores provided quantities of ethanol used in the Restrain Fuel generators that provided a treated weight for ethylene of 3.27 tonnes in the last report. The total tonnage of stored seed potatoes in the United Kingdom had decreased by 10% between 2010 and 2012, while the basic tonnage treated decreased by 32%. In 2014, the total tonnage stored decreased by 8% since 2012, however the basic tonnage treated increased by 46%. Overall, the weight of active substances applied to seed potatoes doubled between 2012 and 2014 and the proportion of untreated crop decreased from 75% in 2012 to 60% in 2014. In 2016, the total weight of active substances applied to stored seed potatoes increased by 6% to 6.14 tonnes from 5.78 tonnes in 2014. This was despite an increase of 23% in the total tonnage of seed potatoes stored and partially helped by the untreated tonnage of seed potatoes stored which increased by 15% over the same period to represent 54% of the total seed potato crop stored in 2016. After the introduction of the CIPC Stewardship Scheme in 2008, the 2016 report indicates a cessation in the usage of chlorpropham in ware potato stores where other commodities are stored. Between 2008 and 2016, the percentage of farm stores storing other commodities and using chlorpropham fell from 13% to none, whilst the percentage in merchant stores fell from 5% to none. 5 INTRODUCTION The Expert Committee on Pesticides (ECP) advises government on all aspects of pesticide use.