Annex 1. Project Report to DEFRA

Annex 1. Project Report to DEFRA.

DEFRA commission PS2108

Towards cost effective registration of natural semiochemicals for crop protection in the UK

Report for distribution and discussion with PSD

Authors: Rothamsted Research, and JSC International Ltd.

Date: 10th August 2005

Contents

Contents......

1.Introduction......

2.Literature searching......

2.1Chemical Search Terms:......

2.2Additional Search Terms:......

2.3Databases searched......

2.4Private databases and begging for data......

2.5Data storage:......

2.6Obtaining reprints......

2.7Translation......

3.Data collation......

3.1Abstracting data into Tier II documents......

3.2Specific Points on Completing Dossier Summaries......

Section 1 Identity......

Section 1 Physical and chemical properties......

Section 2 Analytical methods......

Section 3 Toxicological and metabolism studies......

Section 4 Residues......

Section 5 Fate and behaviour in the environment......

Section 6 Ecotoxicological studies......

Classification and labelling......

4.Assessment of costs required to complete the packages to a standard suitable for regulatory purposes

Appendix 1 - Use scenarios used as the basis of the data gap analysis......

Appendix 2 Summary of costs outstanding to complete the packages for regulatory submission

1.Introduction

Naturally occurring semiochemicals, that control the behaviour or development of pests and their hosts, can be extracted from cultivated non-food plants and deployed for the protection of larger areas of crop plants. However, naturally derived semiochemicals, that are applied as “plant protection products”, require registration under EC Directive 91/414/EEC.

In the United Kingdom, there is considerable demand for use of alternatives in crop protection to conventional synthetic broad-spectrum pesticides which have a predominantly toxic mode of action on the target pest. Since semiochemicals act as signals regulating behaviour or development of the pest (or crop), rather than by toxic or other direct physiological effects, effective pest control methods based on their use may be more acceptable not only over synthetic conventional pesticides but also over botanically-derived toxicants. Although it is also ‘conventional wisdom’ that many do not have very good or predictable efficacy; semiochemicals can be valuable components of integrated pest management programmes particularly because their risk profiles can be favourable in comparison with conventionally available synthetic chemicals (e.g. due to their specific mode of action combined with low effective use rates), and they may also be acceptable in organic production systems.

However, the specific profile of the candidate semiochemicals which are proposed for registration and subsequent commercialisation must be demonstrated objectively in the formal assessment of potential hazards and risks made by the Pesticide Safety Directorate (PSD) based on information contained in a registration dossier. The developing industry has indicated that data requirements, their presentation and assessment procedures are based too heavily on procedures for conventional pesticides and thus appear a potential barrier to commercialisation, and hence the availability, of more desirable control methods. The publication of information arising from pilot registration exercises would assist this emerging industry with development of appropriate registration packages and further exploitation of semiochemicals. This would in turn contribute to addressing the demand for pest control systems which exploit natural processes e.g. biorational alternatives which may be preferable to some conventional methods and currently available GM technologies.

The main objective of this research project was be to take information on three specific examples of semiochemicals and assess the availability of data and produce packages suitable for registration, presenting this information in the dossier format required under 91/414/EEC which is acceptable to regulatory authorities. The main activities involved providing data for long term previous and current human contact with the three natural semiochemicals, together with toxicological data as available for each, or for closely related natural products, and any appropriate synthetic analogues. Any further data required will be provided by ongoing research in other projects, with this study concentrating on the compilation of existing data, and those from other sources, and the computation of or extrapolation from these data for the purposes of the registration packages.

Europe has adopted the Organisation for Economic Co-operation and Development (OECD) harmonised approach where much of the core chemical data set can be reduced for semiochemicals[1] that affect the behaviour of arthropods. Further reductions in data requirements are possible for Straight-Chained Lepidopteran Pheromones (SCLPs) which are pheromones with a well-defined unbranched aliphatic structure, characteristic of the Lepidoptera. Thus it was considered of value to consider the OECD semiochemicals guidance document[2] while compiling the draft dossier documents in this project. The guidance was useful in some cases but of limited value (and occasionally misleading) at times for these non-SCLP substances.

OECD have compared the inherent properties of semiochemicals with properties of conventional chemicals. It is considered that arthropod semiochemicals products pose lower potential risk to human health and the environment than conventional pesticides for a number of reasons. All these factors minimise the risk of adverse effects from the use of semiochemicals:

• They act by modifying behaviour of the pest species rather than killing it
• They are more target specific than conventional insecticides
• They are generally effective at very low rates so can be used at concentrations close to those in nature
• They are generally volatile and usually dissipate rapidly in the environment thus minimising residues in crops and exposure of non-target organisms
• End use products may be used in dispensers that result in little direct exposure to humans and non-target organisms
• Furthermore, SCLPs are considered to be of low toxicity to mammals.

Three natural semiochemicals were chosen and a probative registration package assembled for each, to devise a general framework. These were:

1.crops. Hop β-acids. This material is extracted from brewing hops and acts as an effective antifeedant (a semiochemical interfering with feeding behaviour) against, for example, the two-spotted spider mite, Tetranychus urticae, a pest of high value horticultural

2. Methyl salicylate. This is employed as the major component of a fully definable essential oil (oil of wintergreen) and acts as an indicator of plant stress, and therefore non-host status, thereby reducing aphid colonisation of, for example, cereal crops.

3.cis-Jasmone. This is obtained as a major component of various essential oils and acts as a plant signal, or plant activator, that usefully “switches on” plant defence and reduces thereby, for example, aphid numbers on cereal crops.

The milestones for the project were:

1. Search available literature and databases for all available

data for the three semiochemicals. (end of month 6)

1. Collate data under EC directive 91/414 format, conduct a data gap analysis

and define areas where further research is required.(end of month 8)

1. Construct and maintain a web site, which will incorporate the data relevant to each registration package as it is assembled. (end of month 7)

1. Assemble example registration packages for the three semiochemicals and submit to PSD for scrutiny. end of month 12)

The project commenced on 01/01/2004.

There were two objectives in the project; to develop registration dossiers for three semiochemicals and also to comment on the challenges encountered in attempting to do this using data from the public domain. The documents produced which are summarised in the table below are not forming a submission to PSD at the current time, but they will be used as the basis of a future regulatory submission.

The following table summaries the outputs according to each milestone.

Milestone / Who / Outputs
Search available literature and databases for all available data for the three semiochemicals / RR / JSC / Microsoft Access database format summarising all relevant papers found.
Comments on the procedure used are presented in this report.
Reports found were collated as below.
Collate data under EC directive 91/414 format… / RR / JSC / Document K-II Sections 1-6 Reference lists Sections 1-6
…conduct a data gap analysis… / JSC / Findings presented in this report and JSC overview comment sheets associated with each M-II dossier document.
…and define areas where further research is required / JSC / Findings presented in this report with comments on costings to complete the dossiers to submission standard.
Construct and maintain a web site, which will incorporate the data relevant to each registration package as it is assembled / RR / A draft format of a web site has been produced and a final version will need to be agreed by RR, JSC and PSD
Assemble example registration packages for the three semiochemicals and submit to PSD for scrutiny / RR / JSC / Document K-II Sections 1-6 Reference lists Sections 1-6
RR / JSC / Document D-1 GAP forms
RR / JSC / Draft Document M-II Sections 1-6, plus:
JSC / -- Additional input to complete the methyl salicylate M-II, Section 3 (Toxicology section)

RR: Rothamsted Research

JSC: JSC international Ltd.

The documents generated and listed above will be of value alongside this report as worked examples to form the basis of discussions with PSD, and complete the project. We hope that the experiences gained compiling these three examples will allow productive discussion on potential ways forward for the regulatory process for semiochemicals and plant extracts.

2.Literature searching

As wide a selection of databases possible, both free and by subscription were searched. Private databases such as the Research Institute for Fragrance Materials (RIFM) and the Flavor and Extract Manufactures Association (FEMA) database were a different matter (see below). All databases were searched using a range of keywords, however, with cis-jasmone and hop -acids the references were usually few, so that the databases were searched using chemical terms only and relevant hits found by manual searching the output. Search terms were adjusted to suit the requirements or content of the database.

2.1Chemical Search Terms:

SemiochemicalSearch Terms

Methyl salicylate:methyl salicylate; methyl AND salicylate (Boolean); methyl (1W) salicylate (word proximity); salicylate; salicylic; wintergreen; 119-36-8 (CAS number).

cis-Jasmone:cis-jasmone; (Z)-jasmone; Z-jasmone; jasmone; jasmon*; cis AND jasmone (Boolean); 488-10-8 (principal CAS number).

Hop -acids:hop beta-acids; (hops OR hop) AND beta AND acids (Boolean); hops; lupulone; 468-28-0 (CAS number); lupulon; lupulone OR lupulon (Boolean); colupulone; adlupulone; prelupulone; postlupulone.

2.2Additional Search Terms:

The majority of the following additional search terms were suggested by JSC International. These were abbreviated using wild cards (* or ?) as shown where the database supported it. Where it did not, the terms were searched individually, e.g. toxicity or toxicology.

Toxicology/human exposure, safety

toxic*; human; medical; poison*; rat; LD50; repro*; diet*; expos*; operator?; worker?; farm*; material safety data sheet; msds.

Environmental exposure/breakdown

environ*; groundwater; water; ecotox*; bird; worm; earthworm; daphnia; bird; plant; metab*; decomp*; degrad*.

Physico-chemical properties

photolysis; hydrolysis; melting; UV; NMR; solubil*; mass AND spectr* (Boolean); vapo?r; logKow; flamm*.

2.3Databases searched

Databases were searched in the following order:

1. Google Google uses non-Boolean searches (assumes AND) but the advanced option can be used to format searches more precisely. I would always recommend searching Google before going on to more specialised databases. It is a remarkably powerful search engine that is capable of finding one obscure search term on page 49 of a 100 page pdf document! Several very useful secondary sources, with references were originally located using Google, for example:

Methyl salicylate: California Environmental Protection Agency (EPA) Department of Pesticide Regulation, Medical Toxicology Branch Methyl Salicylate: Data Gap Status.

Methyl salicylate: National Institute for Occupational Safety and Health: Registry of Toxic Effects of Chemical Substances. Salicylic acid, methyl ester.

National Institute for Occupational Safety and Health: Registry of Toxic Effects of Chemical Substances. 2 - Cyclopenten - 1 - one, 3 - methyl - 2 - (2 - pentenyl) - , (Z) –(cis-jasmone)

RTECS #: GY7301000

National Institute for Occupational Safety and Health: Registry of Toxic Effects of Chemical Substances. Salicylic acid, methyl ester.

UIC/NIH Center for Botanical Dietary Supplement in Women's Health. (Contains chemical structures and physical properties of hop alpha-acids, hop beta-acids and iso-alpha acids.).

Safety assessment of salicylic acid, butyloctyl salicylate, calcium salicylate,C12-15 alkyl salicylate, capryloyl salicylic acid, hexyldodecyl salicylate, isocetyl salicylate, isodecyl salicylate, magnesium salicylate,MEA-salicylate, ethylhexyl salicylate, poassium salicylate, methyl salicylate, myristyl salicylate, sodium salicylate, TEA-salicylate, and tridecyl salicylate.

Committee for veterinary medical products: Salicylic acid, sodium salicylate, aluminium salicylate, basic and methyl salicylate: Summary report.

1. Scirus Scirus is the best non-subscription web-based search engine for scientific papers. It also searches entries in BioMed Net, Medline, PubMed and Science Direct and so saves searching those separately. It searches 167 million web pages. You can specify whether to search web sources or journal sources (or both). It uses Boolean input and has more options in advanced search. Earliest papers date from the 1950s but coverage is thin for early 20th century information. Output is ranked by relevance. One needs to register with Science Direct and BioMed Net to access full text articles (in some cases) although the summary is always accessible.

1. Web of Knowledge (WOK) (formerly Web of Science) Subscription database open to universities, colleges and institutes only and accessed via Athens account. It originally only had references to articles from 1981 to date but now purports to include papers back to 1945, but coverage of early years is patchy. WOK uses Boolean searching in separate database fields. Earlier papers often don’t have an abstract. It can do useful things like citation searching.

1. Beilstein is primarily a very powerful chemical database but is now expanded to include pharmacological data, although their inclusion seems patchy. Data input is by name, name fragment, chemical structure or chemical structure fragment. Beilstein has useful points like “LitLink” in which the web link to the reference is made directly. This was very useful in finding physical properties. Contains early references (19th century), as it is derived from the original Beilstein Handbook. Subscription only and accessed via Athens account. There were many more hits for the pharmacological data for methyl salicylate when I searched the database in June than in January, suggesting that more data are being entered retrospectively. There were little data apart from basic chemical information for cis-jasmone and lupulone and its analogues, although I had found them by using other databases.

1. Edina Biosis Biological abstracts. Boolean searching in database fields. Useful for purely biological and toxicological searching. Accessed via Athens account.

1. CAB Abstracts This database covers international journals in agriculture, forestry, and allied disciplines in the life sciences and from 1973 to current. Accessed via Athens account. Boolean searching in fields. Very few useful hits were found.

1. Toxnet. This site searches ten toxicological databases, including Toxline. Boolean searching in an index field. Rothamsted subscribes to this database.

1. PAN Pesticide database – chemicals. This covers Identification, toxicity, use, water pollution potential, ecological toxicity and regulatory information on pesticides and their active ingredients. Searching is by chemical name, common name, name-fragment or CAS number. There are useful links to regulatory web sites. “Oil of Wintergreen” was located on this database, however, no new data were located that hadn’t already been found. Interestingly, octyl salicylate was also listed.

1. Dialog Web. This searches over 600 databases. Rothamsted subscribed for me for three months. The following were searched:
   

34 and 434 (Sci search), 94 (Japanese science and technology (JICST)), 245, waternet, (CAS), 306 (pesticide fact file), 235 (agroprojects), 10 (Agricola), 156 (Toxfile), 70 (SEDBASE), 161 (occupational safety and health), 229 (drug information full text), 172 (Embase alert), 307 (dictionary of substances and their effects) 317 (chemical safety news base), 331 (material safety data sheets), 337 Registry of toxic effects of chemical substances ((RTECS)), 337 (Chemtox).

Dialog Web was generally the least productive, as surprisingly almost no new relevant information was found that had not already been previously located.

The European Chemical Substances Information System was checked for the three compounds[3] and an IUCLID Dataset was found for methyl salicylate (CAS 119-36-8), thus indicating that in parallel, notifiers are defending the substance in the EU for a range of uses.

The only other database that could have been searched but was not was STN express (CAS online) as it was considered that its coverage had already been adequately searched.

2.4Private databases and begging for data

The most obvious and relevant database is the RIFM and FEMA database. Response to letters asking for access elicited the following (typical) reply:

“Philip,

In response to your e-mail requesting data for methyl salicylate and cis-jasmone, we do not distribute our company data (ex. Moreno and Epstein reports) unless requested by a governmental organization or by a RIFM member. You are able to purchase electronic copies of our monographs for those materials if you are interested, though please note they have not been updated since their respective publication dates.

If you have access to a library, the monographs for those materials were published in special issues of Food and Chemical Toxicology in 1979, v17, p845, Special Issue V and 1978, v16, p821, Special Issue IV.

Sincerely,

Christen Sachse-Vasquez

Technical Manager

Research Institute for Fragrance Materials, Inc.

50 Tice Boulevard

Woodcliff Lake, NJ 07677

Phone: 201-689-8089 ext. 107

FAX: 201-689-8090

”

Unfortunately, as I already had the special issues of Food Chem. Toxicol. that were mentioned and I knew they only contained bottom line summary data.