The assessment of field trials in GMO research around the world and their possible integration in field trials for variety registration.

Most regulations worldwide stipulate that a new genetically modified (GM) crop event has to be compared to its closest non-GM counterpart as a corner stone of the pre-market risk assessment. To this end the GM crop and its comparator should be grown in field trials for a phenotypic comparison as well as for subsequent detailed analysis of the composition of the two crop varieties. A more in-depth globally harmonised approach for the conduct of these field trials is lacking. Only a few countries have formulated detailed protocols for the set-up of GM field trials. In some countries, commercial non-GM reference varieties need to be included in a field study to compile reliable data that indicate the range of natural variation for the compounds tested at the specific location. Detailed analysis of pre-market assessment reports have so far not shown the added value of including these reference varieties in the field trials. In all cases where specific values were found to be outside of the range of the reference varieties, it proved possible to draw conclusions on the part of the pre-market risk assessment that relates to the compositional analysis, on the basis of already available compositional data. With the increasing quality of several databases on compositional data of a growing number of crop species, it seems unlikely that reference varieties will become more important on future occasions. It was furthermore investigated whether this part of the risk assessment can be related to field trial requirements for variety registration with the explicit intention of reducing the data burden on producers of new GM plant varieties. Field trials for variety registration so far include an assessment of phenotypic characteristics that do not cover safety aspects, with the exception of establishment of the glycoalkaloid content in potatoes in the Netherlands and Sweden. It may, however, under certain conditions be relatively easy to exchange data from compositional measurements between variety registration and GM testing procedures, thus laying a foundation for testing the feasibility of combining both pre-market assessment procedures in a single pre-market evaluation path.

The applicability of animal health surveillance systems for post-market monitoring of potential adverse effects of genetically modified (GM) feed.

A facultative post market monitoring of potential health impacts of genetically modified (GM) feedstuffs on livestock consuming these feeds after pre-market risk assessment is under ongoing consideration. Within the IPAFEED database, scientific studies on health effects beyond performance in livestock and the results of a systematic search for evidence of outcome effects due to GM feed are consolidated. These outcomes were reviewed and checked for consistency in order to identify plausible syndromes suitable for conducting surveillance. The 24 selected studies showed no consistent changes in any health parameter. There were no repeated studies in any species by GM crop type and animal species. As such, there is insufficient evidence to inform the design of surveillance systems for detecting known adverse effects. Animal health surveillance systems have been proposed for the post market monitoring of potential adverse effects in animals. Such systems were evaluated for their applicability to the detection of hypothetical adverse effects and their strengths and weaknesses to detect syndromes of concern are presented. For known adverse effects, applied controlled post-market studies may yield conclusive and high-quality evidence. For detecting unknown adverse effects, the use of existing surveillance systems may still be of interest. A simulation tool developed within the project can be adapted and applied to existing surveillance systems to explore their applicability to the detection of potential adverse effects of GM feed.

Genetically modified animals from life-science, socio-economic and ethical perspectives: examining issues in an EU policy context.

The interdisciplinary EC consortium (the PEGASUS project) aimed to examine the issues raised by the development, implementation and commercialisation of genetically modified (GM) animals, and derivative foods and pharmaceutical products. The results integrated existing social (including existing public perception) environmental and economic knowledge regarding GM animals to formulate policy recommendations relevant to new developments and applications. The use of GM in farmed animals (aquatic, terrestrial and pharmaceutical) was mapped and reviewed. A foresight exercise was conducted to identity future developments. Three case studies (aquatic, terrestrial and pharmaceutical) were applied to identify the issues raised, including the potential risks and benefits of GM animals from the perspectives of the production chain (economics and agri-food sector) and the life sciences (human and animal health, environmental impact, animal welfare and sustainable production). Ethical and policy concerns were examined through application of combined ethical matrix method and policy workshops. The case studies were also used to demonstrate the utility of public engagement in the policy process. The results suggest that public perceptions, ethical issues, the competitiveness of EU animal production and risk-benefit assessments that consider human and animal health, environmental impact and sustainable production need to be considered in EU policy development. Few issues were raised with application in the pharmaceutical sector, assuming ethical and economic issues were addressed in policy, but the introduction of agricultural GM animal applications should be considered on a case-by-case basis.

Climate change and food safety: an emerging issue with special focus on Europe.

According to general consensus, the global climate is changing, which may also affect agricultural and livestock production. The potential impact of climate change on food security is a widely debated and investigated issue. Nonetheless, the specific impact on safety of food and feed for consumers has remained a less studied topic. This review therefore identifies the various food safety issues that are likely to be affected by changes in climate, particularly in Europe. Amongst the issues identified are mycotoxins formed on plant products in the field or during storage; residues of pesticides in plant products affected by changes in pest pressure; trace elements and/or heavy metals in plant products depending on changes in their abundance and availability in soils; polycyclic aromatic hydrocarbons in foods following changes in long-range atmospheric transport and deposition into the environment; marine biotoxins in seafood following production of phycotoxins by harmful algal blooms; and the presence of pathogenic bacteria in foods following more frequent extreme weather conditions, such as flooding and heat waves. Research topics that are amenable to further research are highlighted.

Early awareness of emerging risks associated with food and feed production: synopsis of pertinent work carried out within the SAFE FOODS project.

This introduction to the journal's supplement on emerging food and feed safety issues summarizes the objectives and activities of the EU-funded SAFE FOODS project in general and its work package focusing on the early identification of emerging food safety risks, in particular. Within this work package, a number of studies have been carried out on methods enabling the early awareness, identification, and prevention of emerging issues before they can become real risks. The various reviews in this supplement explore the background of the emergence of known food safety risks, both of microbial and chemical/biochemical nature, as well the methods that can be used to identify such risks. Another review identifies a number of chemical and microbiological hazards that are likely to be affected by a changing climate. A major conclusion from these explorative reviews is that monitoring and information exchange systems or procedures are in place to detect, in an early phase, the emergence of potential food safety risks linked to known hazards. Additional systems are needed to predict the development of new potential food safety risks, which are linked to either new hazards or known hazards to which exposure has been altered.

Timely awareness and prevention of emerging chemical and biochemical risks in foods: proposal for a strategy based on experience with recent cases.

A number of recent food safety incidents have involved chemical substances, while various activities aim at the early identification of emerging chemical risks. This review considers recent cases of chemical and biochemical risks, as a basis for recommendations for awareness and prevention of similar risks at an early stage. These cases include examples of unapproved genetically modified food crops, intoxications with botanical products containing unintentionally admixed toxic herbs, residues of unapproved antibiotics and contaminants in farmed aquaculture species such as shrimp and salmon; and adverse effects of chemical and biological pesticides of natural origin. Besides case-specific recommendations for mitigation of future incidents of the same nature, general inferences and recommendations are made. It is recommended, for example, to establish databases for contaminants potentially present within products. Pro-active reconnaissance can facilitate the identification of products potentially contaminated with hazardous substances. In international trade, prevention and early identification of hazards are aided by management systems for product quality and safety, rigorous legislation, and inspections of consignments destined for export. Cooperation with the private sector and foreign authorities may be required to achieve these goals. While food and feed safety are viewed from the European perspective, the outcomes also apply to other regions.

Identification of potentially emerging food safety issues by analysis of reports published by the European Community's Rapid Alert System for Food and Feed (RASFF) during a four-year period.

The SAFE FOODS project undertakes to design a new approach towards the early identification of emerging food safety hazards. This study explored the utility of notifications filed through RASFF, the European Commission's Rapid Alert System for Food and Feed, to identify emerging trends in food safety issues. RASFF information and alert notifications published in the four-year period of July 2003-June 2007 were assigned to categories of products and hazards. For chronological trend analysis, a basic time unit of three months was chosen. Data within each hazard category were analyzed for chronological trends, relationships between product and hazard categories, regions of origin, and countries filing the notifications. Conspicuous trends that were observed included a rise in the incidence of food contact substances, particularly 2-isopropyl-thioxanthone, as well as of chemical substances migrating from utensils and fraud-related issues. Temporary increases were noted in the incidences of the unauthorized dye Para Red, genetically modified organisms, the pesticide isophenfos-methyl, and herring worm, Anisakis simplex. National and European authorities themselves have signaled these conspicuous trends and taken measures. It is recommended to add complementary data to RASFF data, including safety assessments, risk management measures, background data on hazards and surveillance patterns, for a holistic approach towards early identification of emerging hazards.

Early identification systems for emerging foodborne hazards.

This paper provides a non-exhausting overview of early warning systems for emerging foodborne hazards that are operating in the various places in the world. Special attention is given to endpoint-focussed early warning systems (i.e. ECDC, ISIS and GPHIN) and hazard-focussed early warning systems (i.e. FVO, RASFF and OIE) and their merit to successfully identify a food safety problem in an early stage is discussed. Besides these early warning systems which are based on monitoring of either disease symptoms or hazards, also early warning systems and/or activities that intend to predict the occurrence of a food safety hazard in its very beginning of development or before that are described. Examples are trend analysis, horizon scanning, early warning systems for mycotoxins in maize and/or wheat and information exchange networks (e.g. OIE and GIEWS). Furthermore, recent initiatives that aim to develop predictive early warning systems based on the holistic principle are discussed. The assumption of the researchers applying this principle is that developments outside the food production chain that are either directly or indirectly related to the development of a particular food safety hazard may also provide valuable information to predict the development of this hazard.

Comparative safety assessment of plant-derived foods.

The second generation of genetically modified (GM) plants that are moving towards the market are characterized by modifications that may be more complex and traits that more often are to the benefit of the consumer. These developments will have implications for the safety assessment of the resulting plant products. In part of the cases the same crop plant can, however, also be obtained by 'conventional' breeding strategies. The breeder will decide on a case-by-case basis what will be the best strategy to reach the set target and whether genetic modification will form part of this strategy. This article discusses important aspects of the safety assessment of complex products derived from newly bred plant varieties obtained by different breeding strategies. On the basis of this overview, we conclude that the current process of the safety evaluation of GM versus conventionally bred plants is not well balanced. GM varieties are elaborately assessed, yet at the same time other crop plants resulting from conventional breeding strategies may warrant further food safety assessment for the benefit of the consumer. We propose to develop a general screening frame for all newly developed plant varieties to select varieties that cannot, on the basis of scientific criteria, be considered as safe as plant varieties that are already on the market.

Safety assessment, detection and traceability, and societal aspects of genetically modified foods. European Network on Safety Assessment of Genetically Modified Food Crops (ENTRANSFOOD). Concluding remarks.

The most important results from the EU-sponsored ENTRANSFOOD Thematic Network project are reviewed, including the design of a detailed step-wise procedure for the risk assessment of foods derived from genetically modified crops based on the latest scientific developments, evaluation of topical risk assessment issues, and the formulation of proposals for improved risk management and public involvement in the risk analysis process.

[Nutrition and health--genetically modified food]. / Voeding en gezondheid--genetisch gemodificeerd voedsel.

The genetically modified (GM) crops cultivated at present have new properties of benefit to agriculture. It is expected that in the future GM crops will also be cultivated with more complex genetic modifications that are aimed at improving the nutritional and health value to the consumer. The safety assessment of GM foods before market approval is based on a comparison of the characteristics of the GM food with those of the conventional counterpart. Identified differences are thoroughly tested for their toxicological and nutritional consequences. Supplementary modern analytical techniques are being developed for the assessment of future complex GM foods. No cases of adverse health or nutritional effects in consumers have been reported for the existing generation of GM foods. The feasibility of post-market surveillance of (GM) foods, in order to identify small or chronic effects that have not been noticed in the pre-market phase, is being investigated, yet its value should not be overestimated. Surveillance can be informative in case of specific questions concerning certain products as long as the consumer intake is well documented. To this end traceability and labelling systems must be set up.

Assessment of the food safety issues related to genetically modified foods.

International consensus has been reached on the principles regarding evaluation of the food safety of genetically modified plants. The concept of substantial equivalence has been developed as part of a safety evaluation framework, based on the idea that existing foods can serve as a basis for comparing the properties of genetically modified foods with the appropriate counterpart. Application of the concept is not a safety assessment per se, but helps to identify similarities and differences between the existing food and the new product, which are then subject to further toxicological investigation. Substantial equivalence is a starting point in the safety evaluation, rather than an endpoint of the assessment. Consensus on practical application of the principle should be further elaborated. Experiences with the safety testing of newly inserted proteins and of whole genetically modified foods are reviewed, and limitations of current test methodologies are discussed. The development and validation of new profiling methods such as DNA microarray technology, proteomics, and metabolomics for the identification and characterization of unintended effects, which may occur as a result of the genetic modification, is recommended. The assessment of the allergenicity of newly inserted proteins and of marker genes is discussed. An issue that will gain importance in the near future is that of post-marketing surveillance of the foods derived from genetically modified crops. It is concluded, among others that, that application of the principle of substantial equivalence has proven adequate, and that no alternative adequate safety assessment strategies are available.

Discoloration of dental carious lesions (a review).

The discoloration of dental carious lesions is a marked feature which has received relatively little attention from dental researchers. In this short review, possible causes are considered: the formation of Maillard pigments, melanins, and lipofuscins, and the uptake of food dyes, metals, and bacterial pigments. It is concluded that the Maillard reaction between proteins and small aldehydes produced by bacteria probably accounts for the discoloration.

A novel pyrroleninone cross-link from bovine dentine.

The aim was to identify suspect collagen cross-links in dentine, eluting close to known cross-links in ion-exchange HPLC. Bovine tooth roots as source of dentine were powdered, demineralised, reduced, and acid-hydrolysed. Cross-linking amino acids were isolated from the acid hydrolysate by size exclusion, adsorption, and sequential ion exchange chromatography. In addition to dihydroxylysinonorleucine and hydroxylysylpyridinoline, an unknown cross-link was isolated (V-2). The ultraviolet, mass, and nuclear magnetic resonance spectra support the proposed structure of V-2, a trimeric amino acid with a pyrroleninone nucleus.

Modification of amino acid residues in carious dentin matrix.

The Maillard reaction between sugar and protein has been postulated as the cause for the browning and arrestment of caries lesions. This reaction has been implicated as the cause for decreased degradability of collagen in vivo. The aim of the present study was to verify the occurrence of the reaction in vivo. Carious and sound dentin samples were taken from extracted human teeth and analyzed for the fluorescence characteristic of the Maillard reaction and oxidation and, by HPLC, for Maillard products. In addition, physiological cross-links were analyzed by HPLC. Oxidation- and Maillard reaction-related fluorescence increased in collagenase digests from carious dentin. Advanced Maillard products (carboxymethyllysine and pentosidine) increased, whereas furosine, a marker for the initial reaction, was not observed consistently. This implies no direct addition of sugars to protein, but rather the addi-tion of smaller metabolites and glycoxidation products. In addition, the physiological cross-links hydroxylysinonorleucine and dihydroxylysinonorleucine decreased in carious dentin. Also for hydroxylysylpyridinoline, a decrease was observed, but not consistently. In conclusion, the caries process modifies amino acids in dentin collagen, which can lead to increased resistance against proteolysis and ultimately to caries arrestment.

The Maillard reaction in demineralized dentin in vitro.

The Maillard reaction between carbohydrate and protein has been proposed as a cause of the browning of carious lesions. The aim of the present investigation was to determine the occurrence of this reaction in bovine dentin collagen in vitro and to establish the effect of the reaction on the proteolytic degradation of bovine dentin collagen in vitro. Slices of demineralized bovine dentin were incubated with 0.2 M glucose or buffer for 10 weeks at 37 degrees C. The formation of initial (furosine) and advanced (pentosidine) products of the Maillard reaction in dentin exposed to glucose was confirmed by HPLC. After reduction with NaBH4 to prevent intermediate Maillard products from further reaction, slices were either degraded with collagenase for fluorescence measurement or incubated with trypsin or pepsin to assess enzymatic degradation. Fluorescence characteristic for the Maillard reaction increased in glucose-exposed slices. Degradation of collagen by pepsin, but not by trypsin, was greatly depressed following glucose pretreatment. This may indicate an altered sensitivity to proteolytic degradation; the Maillard reaction thus has a potential role in caries arrestment.

The biotransformation of sulfadimethoxine, sulfadimidine, sulfamethoxazole, trimethoprim and aditoprim by primary cultures of pig hepatocytes.

The in vitro biotransformation of three sulfonamides, trimethoprim and aditoprim, was studied using primary cultures of pig hepatocytes. Incubation of monolayer cultures with sulfadimethoxine (SDM), sulfamethoxazole (SMX) and 14C-sulfadimidine (SDD) resulted in the formation of the corresponding N4-acetylsulfonamide to different extents, depending upon the molecular structure of the drug. Addition of the acetylsulfonamides to the cells showed that these compounds were deacetylated, each to a different extent. A relatively low degree of acetylation (in the case of SDD) was paralleled by extensive deacetylation (i.e. AcSDD), whereas extensive acetylation (i.e. SMX) was in concert with minor deacetylation (i.e. AcSMX). The addition of bovine serum albumin to the medium resulted in a decrease in conversion of sulfonamides as well as acetylsulfonamides. The main metabolic pathway of 14C-trimethoprim (TMP) was O-demethylation with subsequent conjugation. Two hydroxy (demethyl) metabolites were formed, namely 3'- and 4'-demethyl trimethoprim, which were both glucuronidated while 3'-demethyl trimethoprim was also conjugated with sulphate. The capacity to form conjugates with either glucuronic acid or sulphate was at least as high as the capacity for O-demethylation since more than 90% of the metabolites were excreted as conjugates in the urine of pigs. Addition of 14C-aditoprim (ADP) to the hepatocytes led to the N-demethylation of ADP to mono-methyl-ADP and didesmethyl-ADP. During the incubation another three unknown ADP metabolites were formed. In contrast to TMP, no hydroxy metabolites or conjugated metabolites of aditoprim were formed. These in vitro results were in agreement with the in vivo biotransformation pattern of the studied sulfonamides and trimethoprim in pigs.

The influence of the organic matrix on demineralization of bovine root dentin in vitro.

The effect of matrix degradation on the rate of demineralization of dentin lesions was investigated. It was hypothesized that the demineralized matrix would inhibit the demineralization of the underlying mineralized dentin. Bovine root dentin specimens were alternately demineralized and incubated with either a bacterial collagenase or buffer (control). The demineralization was carried out under various conditions: Acetic acid solutions were used to form incipient and advanced erosive lesions, and lactic acid solutions containing a bisphosphonate were used to form incipient subsurface lesions. Under all conditions, the demineralization was found to be accelerated when the matrix was degraded by collagenase. This increase was more pronounced in advanced erosive lesions than in incipient lesions. Microscopic examination of collagenase-treated specimens revealed that the matrix of erosive lesions contained several layers of differently affected matrices, whereas the matrix of subsurface lesions appeared to be equally affected throughout the lesion. In conclusion, the matrix degradation was different in erosive and subsurface lesions but promoted the demineralization in both types of lesions.