R. Onori

Long-term administration of low doses of mycotoxins to poultry. 1. Residues of aflatoxin B1 and its metabolites in broilers and laying hens.

A study was performed to determine aflatoxin residues in tissues and organs of male broilers and hens that had been fed a diet contaminated with 50 micrograms/kg aflatoxin B1 (AFB1). Residue levels of AFB1, aflatoxicol (Ro), aflatoxin M1 (AFM1) and aflatoxin B2a (AFB2a) were determined by an HPLC method and, with the exception of AFB2a, were detected in the liver, kidney and thigh of both male broilers and hens. The highest levels found were for Ro in liver (1.10 and 0.60 micrograms/kg for male broilers and hens, respectively). On the other hand no detectable amounts of aflatoxins were found in any tissue after withdrawal periods of 14 and 33 days for male broilers and laying hens respectively.

Long term administration of low doses of mycotoxins in poultry. 2. Residues of ochratoxin A and aflatoxins in broilers and laying hens after combined administration of ochratoxin A and aflatoxin B1

The effects of combined administration of ochratoxin A (OA) and aflatoxin B1 (AFB1) on the occurrence and the levels of residues of mycotoxins in poultry have been investigated. Male broilers and laying hens were fed from 14 days old with standard diets contaminated with 50 micrograms/kg OA and 50 micrograms/kg AFB1. Two groups of broilers and hens were withdrawn from contaminated feed at 37 and 88 days, respectively. At the time of sacrifice no significant lesions were found. Residues were compared with those found after administration of either toxin alone in former trials. Combined treatment resulted in higher content of OA in broiler livers (40 versus 5.0 micrograms/kg) and, to a lesser extent, in kidneys and skin, and of AFB1 in broiler liver and kidney (0.15 versus 0.02 microgram/kg and 0.40 versus 0.05 microgram/kg respectively). Laying hens showed smaller differences (0.20 versus 0.10 microgram/kg in liver and 0.32 versus 0.08 in kidneys). Withdrawal from treatment led to the almost complete disappearance of OA residues in broilers and in hens. These results show a synergistic effect of OA and AFB1, particularly in broilers.

HPLC determination of the total content of aflatoxins in naturally contaminated eggs in free and conjugate forms

A study was undertaken to evaluate the total aflatoxin content in naturally contaminated eggs. Two pools of eggs from laying hens were collected after 2 and 7 days of treatment with aflatoxin B1 (AFB1). An HPLC method has been developed for the determination of AFB1, aflatoxin M1 (AFM1), aflatoxin B2a (AFB2a) and aflatoxicol (Ro) both in free form and after release from water-soluble conjugates. The bound form was cleaned up after acid hydrolysis of the aqueous phase. Eggs collected after 2 days of treatment revealed residues of AFB1, AFB2a and Ro in the organic phase, but none in the aqueous portion. After 7 days of treatment both AFB1 and its hydroxy derivative were found in the organic phase but the aqueous portion showed only hydroxylated metabolites accounting for 35% of the total aflatoxin content.

Testing the interaction between analytical modules: an example with Roundup Ready®soybean line GTS 40-3-2

BackgroundThe modular approach to analysis of genetically modified organisms (GMOs) relies on the independence of the modules combined (i.e. DNA extraction and GM quantification). The validity of this assumption has to be proved on the basis of specific performance criteria.ResultsAn experiment was conducted using, as a reference, the validated quantitative real-time polymerase chain reaction (PCR) module for detection of glyphosate-tolerant Roundup Ready® GM soybean (RRS). Different DNA extraction modules (CTAB, Wizard and Dellaporta), were used to extract DNA from different food/feed matrices (feed, biscuit and certified reference material [CRM 1%]) containing the target of the real-time PCR module used for validation. Purity and structural integrity (absence of inhibition) were used as basic criteria that a DNA extraction module must satisfy in order to provide suitable template DNA for quantitative real-time (RT) PCR-based GMO analysis. When performance criteria were applied (removal of non-compliant DNA extracts), the independence of GMO quantification from the extraction method and matrix was statistically proved, except in the case of Wizard applied to biscuit. A fuzzy logic-based procedure also confirmed the relatively poor performance of the Wizard/biscuit combination.ConclusionsFor RRS, this study recognises that modularity can be generally accepted, with the limitation of avoiding combining highly processed material (i.e. biscuit) with a magnetic-beads system (i.e. Wizard).

Evaluation of lead, cadmium, chromium, copper and zinc by atomic absorption spectroscopy in durum wheat milling products in relation to the percentage of extraction

36 samples representative of the 1981 Italian durum wheat crop were separated by an industrial Italian milling process and the products obtained analyzed by AAS for their Pb, Cd, Cr, Cu, Zn content. The results obtained were: Pb ranging from 0.04 to 0.80 ppm, Cd from 0.02 to 1.39 ppm, Cr from 0.05 to 1.60 ppm, Cu from 1.8 to 39.7 ppm and Zn from 8.8 to 117.6 ppm. Although Cr content was relatively homogeneous, Pb, Cd, Cu and Zn distribution in the various mill products proved to be rather inhomogeneous. Maximum contamination for Pb, Cd and Cr, was appreciably lower than in previous studies.

Case studies on genetically modified organisms (GMOs): Potential risk scenarios and associated health indicators

Within the frame of the EU-funded MARLON project, background data were reviewed to explore the possibility of measuring health indicators during post-market monitoring for potential effects of feeds, particularly genetically modified (GM) feeds, on livestock animal health, if applicable. Four case studies (CSs) of potential health effects on livestock were framed and the current knowledge of a possible effect of GM feed was reviewed. Concerning allergenicity (CS-1), there are no case-reports of allergic reactions or immunotoxic effects resulting from GM feed consumption as compared with non-GM feed. The likelihood of horizontal gene transfer (HGT; CS-2) of GMO-related DNA to different species is not different from that for other DNA and is unlikely to raise health concerns. Concerning mycotoxins (CS-3), insect-resistant GM maize may reduce fumonisins contamination as a health benefit, yet other Fusarium toxins and aflatoxins show inconclusive results. For nutritionally altered crops (CS-4), the genetic modifications applied lead to compositional changes which require special considerations of their nutritional impacts. No health indicators were thus identified except for possible beneficial impacts of reduced mycotoxins and nutritional enhancement. More generally, veterinary health data should ideally be linked with animal exposure information so as to be able to establish cause-effect relationships.

Exposure of livestock to GM feeds: Detectability and measurement

This review explores the possibilities to determine livestock consumption of genetically modified (GM) feeds/ingredients including detection of genetically modified organism (GMO)-related DNA or proteins in animal samples, and the documentary system that is in place for GM feeds under EU legislation. The presence and level of GMO-related DNA and proteins can generally be readily measured in feeds, using established analytical methods such as polymerase chain reaction and immuno-assays, respectively. Various technical challenges remain, such as the simultaneous detection of multiple GMOs and the identification of unauthorized GMOs for which incomplete data on the inserted DNA may exist. Given that transfer of specific GMO-related DNA or protein from consumed feed to the animal had seldom been observed, this cannot serve as an indicator of the individual animals prior exposure to GM feeds. To explore whether common practices, information exchange and the specific GM feed traceability system in the EU would allow to record GM feed consumption, the dairy chain in Catalonia, where GM maize is widely grown, was taken as an example. It was thus found that this system would neither enable determination of an animals consumption of specific GM crops, nor would it allow for quantitation of the exposure.

A risk assessment of the food supply chain: vulnerability against terrorist or criminal contamination

The food supply chain has been recognised by the USA and the EU as a critical infrastructure, and it should be considered a target for possible terrorist attacks. In this paper, we present a methodological approach developed within the EU project SecuFood to evaluate the risk associated with this threat. The usefulness of the approach is related to the improvement of the analysis of food supply chain risk in terms of the potential threats, the vulnerability of the system, and the effectiveness of counter measures. The followed approach is based on identifying biological and chemical hazards, analysing those biological and chemical agents, and determining the risk level they present in the main phases of the food supply chain. We consider the feasibility of an attack (what we call likelihood), taking into account the accessibility and manageability of the contamination agents, the vulnerability of the supply chain for specific products, and the possible adverse consequences.

The relevance of sampling for the control of genetically modified organisms in the agri-food chain

Abstract: Sampling is a critical procedure whenever a decision is taken based on the results of sample measurements. Even though optimizing sampling plans can lead to procedures that are more cost effective, sampling is often not treated with due importance. A feasible sampling procedure that is relevant for all the diverse scenarios in which GMOs (genetically modified organisms) are heterogeneously present in primary production and along feed and food chains has not yet been produced or adopted at the European level. In this chapter existing legislative provisions, norms and guidelines are described and their pros and cons considered. Information on specific provisions for sample preparation and sampling uncertainty is also given.