GB2367911A - A system for media contamination risk analysis and for identifying priorities for testing for the presence and/or levels of contaminants - Google Patents

Abstract

A system for media contamination risk analysis and for identifying and prioritising which contaminants ought to be tested comprises: means for collecting data characteristic of a medium or media in which contamination is suspected; means for collecting and collating parameters relating to influencing factors on level of contamination; means for analysing said data and influencing factors to generate data indicating risk of contaminant residues being present; means for identifying likely concentrations of residues; means for prioritising, according to pre-selected weighting factors, which residues ought to be sought by conducting testing analysis and applying priority tags to the data; means for transmitting the data generated, including priority tags, to a location for online display thereof; and means for generating prompts according to the characteristics of the medium or media and suspected contaminants to derive further data for improving the accuracy of the generated data, whereby priority for testing of residues is identified according to established guidelines to provide a cost-effective regime for contaminant testing. The system is for use in the food and feed industry to enable farmers and growers to assess the contamination risk in a crop.

Description

A SYSTEM, METHOD AND ARTICLE OF MANUFACTURE FOR MEDIA CONTAMINATION RISK ANALYSIS AND FOR IDENTIFYING PRIORITIES FOR TESTING FOR THE PRESENCE AND/OR LEVELS OF CONTAMINANT Field of the Invention The present invention relates to risk analysis of media contamination and more particularly relates to using accumulated data and experience to evaluate the presence of particular contaminants and to identify a priority for testing for the presence of said contaminants.

A number of professional bodies have been involved in chemical analysis and biological characterisation of foods and feed for many and up to 40 years and each has acquired a pool of knowledge which is applied individually to each sample presented for testing. The Applicant has accumulated a knowledge base which, especially in the sphere of contaminants, is unsurpassed in breadth, depth, accuracy and understanding. The knowledge base grows constantly Advice to clients on the chemical or biological investigations that they should conduct involves assessment of the risks and costs to the client Currently, the risk assessment process requires experts to collect (and recollect) detailed information on a case-by-case basis from a large number of very diverse sources, forming a constantly growing informal database, and then to weigh up the implications of a host of factors that impinge on the case, to tailor the advice for the individual client or for the individual medium to be tested.

The current system is largely based on memory and requires access to highly experienced people. It places the experts under pressure to access all relevant information and to try to ensure that the advice is both consistent and up-to-date Information relating to contaminants is constantly being updated and modified as new products are brought onto the market, acceptable residue levels of given contaminants change and public awareness and opinion alters Estimation and weighting of the effects of influencing factors have no simple, formal basis or rationale. Therefore when experts leave, or are otherwise not accessible, those given the task of providing advice have to start from scratch and may arrive at different (potentially even irrational) conclusions. The whole task involves consideration of so much information that even experts who provide advice on a regular basis cannot do so with absolute consistency. In the (hitherto unusual) event that a risk assessment proves erroneous, there is no means for a formal analysis of the factors leading to the error, nor to ensure that such an error could not recur.

In some instances rough rules of thumb are applied and a certain amount of instinctive intuition is used to formulate a testing strategy for a customer In the food and feed industry particularly there is a requirement on growers and producers to ensure that their product is as safe as possible for consumption, whether it be for direct human consumption or for animal feed. Thus, growers and producers are expected to show due diligence in the monitoring of possible contaminants to their product It is an object of the present invention to seek to alleviate the above disadvantages and to provide means for increasing the reliability and consistence of advice tendered to ensure accurate risk analysis and prioritising of contaminant testing.

It is a further object of the present invention to provide an on-line advice system enabling the food and feed industries (in the broadest sense), and their customers,

to decide on requirements for chemical analysis and biological investigation, based on multi-dimensional risk assessments It is a yet further object of the present invention to provide an expert system for deciding on the acceptability of chemical, physical, biological or cultural treatment regimes and on requirements for chemical analysis and biological investigation, based on multi-dimensional assessment of risks and costs In the present application, the term"medium"or"media"is intended to be directed to any physical entity which may carry, contain or otherwise incorporate a contaminant. Thus, the term is meant to include, for example, soil, water, air, crops, animal feed, manufactured or processed food, materials used for containing or wrapping food or feed and the like. It will be appreciated by the skilled reader that the application of the invention is particularly diverse.

It will also be appreciated that the term"contaminant"or"contaminant residue"is to be interpreted in the broadest sense and is to include components which may be desirable and undesirable. Some of the contaminants are of natural origin and may be hazardous or non-hazardous. Of the less desirable components the following list is to be taken only as an example of the contaminants considered pesticide residues ; veterinary drug residues, mycotoxins; heavy metal and industrial contaminants; nutrients ; natural constituents, pest and disease control products; pest and disease identifiers ; microbiological contaminants, genetically modified organisms (GMO); authenticity and food ingredient species, allergens and packaging and processing contaminants The above list should in no way be taken as exhaustive and is intended merely to be illustrative.

Statements of the Invention Accordingly, the present invention provides a system for media contamination risk analysis and for identifying and prioritising which contaminants ought to be

tested, the system comprising. a) means for collecting data characteristic of a medium or media in which contamination is suspected, b) means for collecting and collating parameters relating to influencing factors on level of contamination ; c) means for analysing said data and influencing factors to generate data indicating risk of contaminant residues being present, d) means for identifying likely concentrations of residues; e) means for prioritising, according to pre-selected weighting factors, which residues ought to be sought by conducting testing analysis and applying priority tags to the data, f) means for transmitting the data generated, including priority tags, to a location for display thereof, and

g) means for generating prompts according to the characteristics of the I medium or media and suspected contaminants to derive further data for improving the accuracy of the generated data, whereby priority for testing of residues is identified according to established guidelines to provide a cost-effective regime for contaminant testing The invention further provides a user interface for a contaminant risk analysis system including means for a user to interactively explore how the risk of a contaminant residing in a medium such as foodstuffs, soil, water or any part of a food chain may change according to a number of influencing factors The user interface further includes means for generating recommendations for testing for identified contaminants, which recommendations are preferably prioritised according to recognised weighting factors including, for example, toxicity, non-approved use, adverse public opinion and contaminant longevity (half-life).

The invention also provides a method for analysing contamination risk of media and for identifying which contaminant residues ought to be tested, the method comprising : a) collecting data characteristic of a medium or media in which contamination is expected; b) collecting and collating parameters relating to influencing factors on level of contamination, c) analysing said data and influencing factors to generate data indicating risk

of contaminant residues being present ; Z=l 7 d) identifying likely concentrations of residues ; e) prioritising, according to pre-selected weighting factors, which residues ought to be sought by conducting testing analysis and applying priority tags to the data; f) transmitting the data generated, including priority tags, to a location for display thereof ; and g) generating prompts according to the characteristics of the medium or media and suspected contaminants to derive further data for improving the accuracy of the generated data,

thereby identifying a priority base schedule for testing of residues according to established guidelines to provide a cost-effective regime for contaminant testing The invention yet further comprises a method of providing an indication to a user of the probability of contaminant risk in a medium or media, the method comprising. interactively exploring how the risk of a contaminant residing in a medium such as foodstuffs, soil, water or any part of a food chain may change according to a number of influencing factors, and

generating recommendations for testing of identified contaminants, said I recommendations being prioritised according to recognised weighting factors including, for example, toxicity, non-approved use, adverse public n opinion and contaminant longevity (half-life) The method preferably includes the steps of concurrently displaying a plurality of input objects, one or more being configured to generate question fields to be completed by a user, generating a display based on decisions made from the input objects and question field inputs; and determining and displaying a set of recommendations and associated priorities based on the input objects and question field inputs For assessing pesticide residues in a plant crop as an exemplifying embodiment, the method preferably includes assessing terminal residue levels. estimated from data relating to crop variety grown, date of harvest, total plant mass at harvest, and marketed plant part and mass; applying appropriate mathematical functions to

estimate the plant growth patterns, derived from information on sowing, planting, I harvesting, and consequently deriving the plant mass of various parts of the plant. residue distribution is estimated from physio-chemical characteristics of the pesticide and timing of the application; pesticide treatment rates are estimated from label recommendations (or user entered data) and estimated deposition efficiency factors derived from plant mass estimates.

A new product has been conceived that formalises and computerises the decisionmaking processes and accesses the vast quantities of supporting data from databases. This product is preferably made available on-line to clients as a chargeable service and for use internally to reduce the costs and inconsistencies of decision-making. The databases of supporting information are updated constantly and, because the decision-making processes) is substantially automated, the system can be adjusted as required to take into account of emergent information The product is conveniently adapted to utilise existing database software and Internet technology and is intended for access via personal computer and the like In a further aspect, the present invention provides a machine-readable medium having stored thereon data representing sequences of instructions for execution by a processor, the instructions causing the processor to display concurrently a series of input objects representative of contaminant classes, the input objects being configured to generate question fields to be completed by a user, generate a display based on decisions made from the input objects and question field inputs ; determining risk assessments based on said inputs, and displaying a set of recommendations and associated priorities for conducting contaminant testing.

The technical advantages of the invention include (i) availability of completely consistent expert advice on demand, around the clock, throughout the year, relating to all decisions on chemical and biological examination of media such as soil, water, air and particularly food and feed ; (ii) redirecting valuable resources to more productive areas, for example, freeing experts from handling individual enquiries and allowing them to contribute to refinement (and correction, if necessary) of the product, as and when required; (iii) retaining the benefits of expert knowledge and understanding when individual experts retire or leave and aiding in the training of future specialists/experts Although the product relies on subjective assessments of the data, the data and interpretation algorithms have a logical and structured nature so that the knowledge and understanding can be transferred rapidly in training new experts, without having to work alongside existing experts for prolonged periods ; (iv) incorporating existing and emergent relevant information from any source, including new expert opinion and product feedback from clients, into the advice given; (v) providing reports from incomplete input data, whereby users of the product are prompted for all relevant/available input information, to enable the best possible advice to be obtained, but the product provides assessments from incomplete input data,

(vi) facilitating modification of data, risks and weighting factors so that the it 4 :) advice on complex issues relating to chemical and biological

characterisation of foods, feeds, etc., which is based on formal decision making processes, each part of which is readily amenable to modification according to emergent information, without having to change the whole, (vii) basing the advice on all relevant current information, including factors influencing the occurrence, distribution, persistence and fate of contaminants, etc, the hazards associated with such contaminants, and the costs and limitations of available detection methods, (viii) highlighting specifically critical elements of the advice (with explanation of the more obscure underlying problems) to ensure that clients focus on the most important issues;

(ix) providing self-correcting and/or iterative assessments enabling clients to CD learn quickly which parameters lead to lower or higher risks and costs, n thereby benefiting both manufacturers, growers and consumers of food or, more generally, users of the product being analysed for contaminants, (x) providing clients with a comprehensive suite of supporting information, enabling to achieve a more complete understanding of the issues relating to their own problems ; (xi) updating clients, automatically (where available), with new information that may affect the risks and the weighting of risks in their particular circumstances, as the product is amended, extended or refined and when risk factors change in response to emergent information Further technical advantages may be provided by maintaining and monitoring

assessment data and geographical data to produce profiles of pesticide, herbicide I and other chemical or contaminant use Data may be accumulated and correlated then with particular residues found in different types of media, for example, soil

and crops. In this way, the risk factors and weighting applied can be monitored for review. Furthermore, evidence of contaminants being brought through the food chain may be found, thus highlighting at an early stage possible risk indicators for the food and feed sector.

Brief Description of the Drawings The present invention will now be described more particularly with reference to the accompanying figures which show, by way of example only, one embodiment of system for media contamination risk analysis and for identifying what residues ought to be tested. In the figures: Figure 1 comprises a first screen shot to identify the contaminant considered most relevant to the analysis to be undertaken;

Figure 2 is a screen shot of a menu generated following a user selection of Fi, lcction of "pesticide residues"from the screen illustrated in Figure 1 ; Figure 3 is a screen shot of a completed question driven template based on responses provided by a user in data fields filled in the screen illustrated in Figure

2 ; Figure 4 is a screen shot of a first generated output screen identifying possible unauthorised use of pesticide which in themselves provide warnings of possible future accumulations of residues to unacceptable levels ; Figure 5 is a screen shot of a second generated output screen providing information of risk level and suggested analytical priority; Figure 6 is a screen shot of a third generated output screen facilitating a user to conduct a"due diligence"analysis by comparing official monitoring programmes and guidelines to those programmes conducted or proposed to be conducted by

the user ; and Figure 7 is a screen shot of a fourth generated output screen setting out practical I n advice on sampling and on how amenable the identical pesticide residues are to analysis.

Detailed Description of the Embodiment The invention is now described with reference to a single class of residues selected from options provided from a first screen Example input and output screens form the accompanying figures The worked through example shows what is produced for a grower of lettuce who needed advice on prioritisation of analysis for pesticide residues, based on his own treatment records.

Referring initially to Figure 1, the risk analysis system is intended for providing assessments of risk and sampling advice across a whole range of chemical and biological contaminants. This screen of Figure 1 also provides access to relevant news, to relevant technical and scientific literature, and to changes in the algorithms or databases used by the product that may influence previous and future assessments made for a user. The user selects one or more contaminant classifications to generate a question field driven screen In Figure 1, the user has selected"pesticide residue".

Figure 2 is generated by the system or program associated to indicate the input fields required when the client has selected"pesticide residues"in Figure 1 There are broad questions to answer, as well as payment details to enter.

Figure 3 illustrates a screen generated to provide an input template based on the answers given in the preceding screen to questions on commodity and the information available on treatment history Figure 4 (output screen 1 of 4) informs the client about the approvals status of the treatments made (or planned) Warning lights appear against non-approved treatments (or those made during an approval withdrawal period for a pesticide) The information is generated by comparison with the LIAISON database held by Central Science Laboratory (CSL) Figure 5 (output screen 2 of 4) is the most complex and provides the basis for the assessment of risks in the context of analytical requirements. The approvals status from Figure 4 (output screen 1 of 4) is summarised here, because it indicates the legality of the treatments made. The risks of measurable residues and of exceeding the maximum residue limit (MRL) are derived from complex algorithms that involve : (i) prediction of deposition rates (subjective estimates from estimated or actual application rates and estimated plant size/density), (ii) prediction of the crop growth (derived subjectively from the dates given and from typical growth rates and yields), (iii) prediction of pesticide metabolism and distribution within the commodity (derived from a subjective assessment of published and unpublished data) ; and (iv) prediction of the effects of trimming/processing (derived from subjective assessments of published and unpublished data, estimates from (iii) and

the parts of the plant remaining.

I Test assessments are checked against existing residues data, where these are available, and the algorithms refined if required, before they are incorporated into the product. Relative toxicity is based broadly on published assessments of Acceptable Daily Intake (ADI) or hazard classification but involves arbitrary categorisation and also subjective categorisation (based on whatever toxicological data are available) where no ADI is published.

All pesticides attract adverse public opinion but a subjective assessment is made of the current depth of adverse public opinion Relative analytical costs are considered subjectively for each analyte and a subjective assessment made of whether analytical costs can be lessened by determination of more than one analyte simultaneously.

All the above assessments are subjective, because they have no fixed values and must be based on experience. Accordingly, weighting factors are associated to the values generated for the parameters assessed Influencing factors may also be brought to bear.

The final assessment of analytical priority is derived from an algorithm that weights the risks identified above against the costs of combined analytical costs Because all these assessments are based on calculations involving real or assigned values, any of the individual parameters can be modified separately, on the basis of emergent data. This allows the effects of changed or new parameters to be estimated and checked easily and economically before such changes are introduced to clients.

Figure 6 (output screen 3 of 4) is a detailed analysis of published data (from data bases), presented in a new form, to allow the client to gauge how official monitoring programmes compare with the client's own due diligence programme Figure 7 (output screen 4 of 4) provides factual advice on sampling and analytical requirements (from data bases), to enable the client to prepare and take samples suitable for analysis, and to establish that his contract laboratory provides the service required to conduct his programme properly. The screen also allows the client to download his assessment as an electronic file (for his records) and to make comments if it is perceived that some aspect of the assessment is not as required/expected To ensure the system is maintained up to date, the decision making calculations are adapted and refined in the light of emergent data, with corresponding calculations introduced for all combinations of commodity, sample origin and chemical/biological contaminant. The databases supporting the product are conveniently updated and/or expanded very frequently so that new databases are added as required for new commodities, sample origins and chemical/biological contaminants, and as required to improve the support given to clients Where the system/product is maintained as an Internet accessible or subscriber service, updating is easily facilitated. Where the product is provided as a CD-ROM or similar machine-readable medium, new releases are dispatched to those paying for an updating service.

Advantageously, the product/system is easily adaptable for use in a range of countries and chemical products and names can easily be substituted or appended so as to ensure common factors are applied to common or equivalent contaminant sources, for example.

On-line development of the system is facilitated by client and user co-operation and by availing of the knowledge bases of other experts.

It is envisaged that major users/clients of the product/system will be farmers, growers, importers, exporters, food and feed manufacturers, wholesalers, retailers, consultants, laboratories, and any other organisation or individual requiring instant, expert, low-cost advice on chemical or biological measurements on media such as food and feeds The further relevance of the invention to a wider market

will be appreciated with the full consideration of the wider media to which the system and method may be applied. Analysis of contaminants in other media including soil, water, air, packaging and so on, is equally important in its own right in addition to the knock-on implications for the food and feed sector.

Leaching of contaminants from air, soil and industrial effluent is of major concern to providers of water and waste services and knowledge of additional sources of contamination is particularly important.

To illustrate the basis for risk assessment calculations, the exemplifying embodiment of analysing pesticide residues in lettuce, as a plant crop, is shown below.

A. Assessment of approval risks 1. Approvals for use of the active ingredient and the specific formulation, for the application rate, and for the harvest interval observed, are compared with data input by the user, or those calculated from the dates of sowing, planting, harvest and treatments and the legality of the treatments is indicated. In cases were a legal treatment will become illegal at some future date, an"intermediate"warning is given, with explanation Assessment of approval risk (A) is independent of the residue risk assessment (B) but the use of active ingredients that are not approved for the specific crop, soil type, etc. , is likely to influence adversely the residue risk assessment.

B. Assessment of residue risks and analytical priorities 1. Assessment of terminal residue levels 1.1 Using the description of variety grown (user entered) and date of harvest (user entered), the total plant mass at harvest, together with the plant mass as trimmed for market are estimated.

1. 2 Using an appropriate mathematical function to represent the plant growth pattern, and using the dates given for sowing, planting and harvest, the I I plant mass and effective application target area at the treatment dates are estimated.

1.3 Using the treatment rates (user entered or looked up maximum allowable), allowing for the plant mass (1. 2), and incorporating a deposition efficiency factor, the mass of chemical deposited on the target are estimated 1.4 Using appropriate (pre-determined) factors for the subsequent distribution of the chemical (i e. systemic-including acropetal/basipetal preferential distribution, partially systemic or non-systemic), together with plant mass at treatment and the trimmed and total plant masses at harvest, the proportion of the deposited chemical mass in the trimmed harvested plant mass is estimated. Note that the formulae will differ according to the systemic/non-systemic nature of the chemical: the extremes are (i) to assume uniform distribution at harvest and (ii) to assume that the treatment does not migrate from the treated parts (which may or may not be trimmed off), but intermediate formulae can be used if required.

1.5 The degree of metabolism, to chemicals not included in"residue definitions", is estimated from the estimated plant growth (1. 1 and 1.2) and the limited published information on metabolism (extrapolating from other plants if required).

1 6 The concentration of chemical in the trimmed plant mass is estimated from 1.1, 1.3, 1.4 and 1.5. [Note : typical values to be checked against"real life"existing data, where possible, during testing of the algorithms, prior to releases

2. The value from 1. 6 is compared with the maximum residue limit (MRL) and a risk factor, based on the ratio, is allocated 3. The value from 1.6 is compared with the likely reporting limit (RL) achievable to the chemical and a risk factor, based on the ratio, is allocated.

4. The value from 1 6 is compared with the infant food MRL (0 01 mg/kg) and a risk factor, based on the ratio, is allocated.

5. A factor for the relative toxicity of the chemical is assigned, based on published acceptable daily intakes (ADIs), World Health Organisation (WHO) hazard classification or other relevant information, using the largest (most conservative) factor if different sources of information are not in agreement.

6. A factor is assigned for relative adverse public opinion rating of the chemical (all chemicals have an adverse rating but some are worse than others).

7. A relative cost of analysis is assigned for the chemical, based on in-house costings and whatever external knowledge is available.

8. An appropriate factor is assigned if costs of 7 can be reduced by combining analyses with other chemicals being assessed in the same material (food, etc. ). This factor is used as a divisor of the value from 7.

9. Appropriate weighting is assigned to factors A, B2, B3, B5, B6 and B8, to assess the relative priority for analysis required to show due diligence in controlling the use of the chemicals.

10. Appropriate weighting is assigned to factors A, B4, B5, B6 and B8, to assess the relative priority for analysis required to show due diligence in the production of infant foods If the chemical is proposed or actually banned for use on products intended for manufacture of infant food, the risk factor is increased, whether or not approved for other uses 11. All calculated values, A and B2-B10 are converted, to suitable

alphanumeric strings and symbols, to enable the results to be displayed in 0 a form that is easy to understand and has an immediate impact on the user The example provided as an exemplifying embodiment of the invention serves only to illustrate some of the considerations made to the various parameters relevant to pesticide residues in a crop It will be appreciated that the same residues may be present in different media, for example, crop stubble, soil and waste water used to wash the particular crop, in this case lettuce It should be further appreciated that the example given is a relatively simplistic one allowing for ease of explanation and that the invention is adapted to facilitate the easy handling of complex interactions of media, contaminant and external influencing factor in addition to compensation for incomplete input data for analysis Furthermore, although the above description concentrates on the influence and presence of artificial and deliberately or accidentally applied contaminants, the present invention may also be applied to analysing environmental contaminants in air, soil and water, for example It will of course be understood that the invention is not limited to the specific details described herein, which are given by way of example only, and that various modifications and alterations are possible within the scope of the invention.

Claims (16)

Claims

1. A system for media contamination risk analysis and for identifying and prioritising which contaminants ought to be tested, the system comprising a) means for collecting data characteristic of a medium or media in which contamination is suspected, b) means for collecting and collating parameters relating to influencing factors on level of contamination. c) means for analysing said data and influencing factors to generate data indicating risk of contaminant residues being present. d) means for identifying likely concentrations of residues, e) means for prioritising, according to pre-selected weighting factors, which residues ought to be sought by conducting testing analysis and applying priority tags to the data ; f) means for transmitting the data generated, including priority tags, to a location for display thereof ; and g) means for generating prompts according to the characteristics of the medium or media and suspected contaminants to derive further data for improving the accuracy of the generated data. whereby priority for testing of residues is identified according to established guidelines to provide a cost-effective regime for contaminant testing

2. A user interface for a contaminant risk analysis system including means for a user to interactively explore how the risk of a contaminant residing in a medium such as foodstuffs, soil, water or any part of a food chain may

change according to a number of influencing factors 9

3. A user interface as claimed in claim 2, which includes means foi generating recommendations for testing for identified contaminants, which recommendations are preferably prioritised according to recognised weighting factors including, for example, toxicity, non-approved use, adverse public opinion and contaminant longevity (half-life)

4 A method for analysing contamination risk of media and for identifying which contaminant residues ought to be tested, the method comprising a) collecting data characteristic of a medium or media in which contamination is expected, b) collecting and collating parameters relating to influencing factors on level of contamination, c) analysing said data and influencing factors to generate data indicating risk of contaminant residues being present d) identifying likely concentrations of residues, e) prioritising, according to pre-selected weighting factors, which residues ought to be sought by conducting testing analysis and applying priority tags to the data, f) transmitting the data generated, including priority tags, to a location for display thereof, and

g) generating prompts according to the characteristics of the medium 0 or media and suspected contaminants to derive further data for improving the accuracy of the generated data, thereby identifying a priority base schedule for testing of residues according to established guidelines to provide a cost-effective regime for contaminant testing

5. A method of providing an indication to a user of the probability of contaminant risk in a medium or media, the method comprising interactively exploring how the risk of a contaminant residing in a medium such as foodstuffs, soil, water or any part of a food chain may change according to a number of influencing factors, and generating recommendations for testing of identified contaminants, said recommendations being prioritised according to recognised

weighting factors including, for example, toxicity, non-approved l use, adverse public opinion and contaminant longevity (half-life).

6 A method as claimed in claim 5, which includes the steps of concurrently displaying a plurality of input objects, one or more being configured to generate question fields to be completed by a user ; generating a display based on decisions made from the input objects and question field inputs, and

determining and displaying a set of recommendations and 0 associated priorities based on the input objects and question field inputs.

7. A method as claimed in either claim 5 or claim 6, in which, for assessing pesticide residues in a plant crop as an exemplifying embodiment, the method includes assessing terminal residue levels : estimated from data relating to crop variety grown, date of harvest, total plant mass at harvest, and marketed plant part and mass, applying appropriate mathematical functions to estimate the plant growth patterns, derived from information on sowing, planting, harvesting, and consequently deriving the plant mass of various parts of the plant; residue distribution is estimated from physio chemical characteristics of the pesticide and timing of the application, pesticide treatment rates are estimated from label recommendations (or user entered data) and estimated deposition efficiency factors derived from plant mass estimates

8. A computer product for formalising and automating the decision-making processes for conducting media contamination risk analysis and provides access to the vast quantities of supporting data from associated databases

9 A computer product as claimed in claim 8, in which the databases of supporting information are updated constantly using emergent information provided by users, the system being operable to take into account said emergent information.

10 A machine-readable medium having stored thereon data representing sequences of instructions for execution by a processor, the instructions causing the processor to display concurrently a series of input objects representative of contaminant classes, the input objects being configured to generate question fields to be completed by a user; generate a display based on decisions made from the input objects and question field inputs, determining risk assessments based on said inputs, and displaying a set of recommendations and associated priorities for conducting contaminant testing

11 A system for media contamination risk analysis substantially is herein described with reference to and as shown in the accompanying drawings

12. A user interface for a contaminant risk analysis system substantially as herein described with reference to and shown in the accompanying drawings.

13. A method for analysing contamination risk substantially as herein described with reference to the accompanying drawings

14 A method of indicating probability of contamination risk substantially as

herein described with reference to the accompanying drawings p

15 A computer product substantially as herein described with reference to or shown in the accompanying drawings.

16. A machine-readable medium substantially as herein described with reference to the accompanying drawings