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Total mercury, methyl mercury, and selenium levels in the red meat of small cetaceans sold for human consumption in Japan.

We surveyed the total mercury (T-Hg) and methyl mercury (M-Hg) levels in red meat products (n = 160) from small cetacean species sold for human consumption in markets throughout Japan from 2000 to 2003. Genetic identification showed that the red meat products originated from nine species: false killer whale, bottlenose dolphin, short-finned pilot whale, striped dolphin, rough-toothed dolphin, Risso's dolphin, pantropical spotted dolphin, Baird's beaked whale, and Dall's porpoise. T-Hg and M-Hg concentrations in all red meat products exceeded the provisional permitted levels of T-Hg (0.4 microg/wet g) and M-Hg (0.3 microg/ wet g) in fish and shellfish set by the Japanese government, respectively. The average M-Hg level in the most contaminated species (false killer whale) was 11.5 microg/wet g, and that in the least contaminated species (Dall's porpoise) was about 1.0 microg/wet g, exceeding or equaling the Codex guideline of M-Hg in predatory fishes (1.0 microg/wet g). Contamination levels of T-Hg and M-Hg differed considerably among samples of the nine species and among individuals of a particular species. The highest M-Hg was about 26 microg/ wet g in a sample from a striped dolphin, 87-times higher than the permitted level. The consumption of only 4 g of this product would exceed the provisional tolerable weekly intake of M-Hg for someone of 60 kg body weight (1.6 microg/kg-bw/ week). Although a high correlation between T-Hg and selenium (Se) was observed in these products, the molar ratio of T-Hg to Se was substantially higher than 1. The consumption of red meat from small cetaceans, therefore, could pose a health problem for not only pregnant women but also for the general population.

Animals↗

Food safety and amino acid balance in processed cassava "Cossettes".

Processed cassava (Manihot esculenta Crantz) roots provide more than 60% of the daily energy intake for the population of the Democratic Republic of Congo. Insufficiently processed cassava roots in a diet deficient in sulfur amino acid have been reported to cause the irreversible paralytic disease konzo, afflicting thousands of women and children in the remote rural areas of Bandundu Province. "Cossettes" (processed cassava roots) purchased in several markets of Kinshasa were analyzed for their content of cyanogens, free amino acids, and total protein amino acids. Residual cyanogen levels were below the safe limit recommended by the codex FAO/WHO for cassava flour (10 mg kg(-1)). The amino acid score was evaluated. Lysine and leucine were the limiting amino acids. Methionine content was very low and contributed about 13% of the total sulfur amino acids. Dietary requirements for sulfur amino acids need to be adjusted for the loss caused by cyanogen detoxification.

Amino Acids↗

Occurrence and distribution of organochlorine pesticides (OCPs) in tomato (Lycopersicon esculentum) crops from organic production.

Organochlorine pesticides (OCPs) were quantified by GC-ECD in tomato (Lycopersicon esculentum) during a vegetation period. Plants were harvested at 15, 60, and 151 days after seed germination. Leaves, stem, roots, and fruit (peel and flesh) were analyzed separately. The results showed that tomato plants were able to accumulate OCPs from soils, and a trend to reach the equilibrium among tissues at mature stages was also observed. Endosulfans comprised the main OCP group, probably due to its spray during summer months in the surrounding areas. Banned pesticides such as DDTs, heptachlor, and dieldrin were found. OCPs levels in the fruit were below the maximum residues limits (MRL) considered by the Codex Alimentarius. DDE/DDT and alpha-/gamma-HCH ratios of <1 would indicate recent inputs of DDT and lindane in the environment. The occurrence of OCPs in the study farm, where agrochemicals have never been used, is a result of atmospheric deposition of those pesticides.

DDT↗

Levels of organochlorine pesticides in soils and rye plant tissues in a field study.

The organochlorine pesticides are lipophilic and persistent and tend to accumulate in soils and growing plants. The contamination of growing plants occurs by adhesion of volatile substances from the air to the plant surface and by the migration of contaminants through xylem in inner ascendant transport. Persistent organochlorine pesticides (HCB, alpha,gamma-HCH, pp'DDE, op'DDT, pp'DDT) levels were determined in soils and rye plants. The aims of the study were the monitoring of organochlorine pesticide concentrations and the comparison of these levels among soil, rye straw, and rye grains. Fifty soil samples and 50 rye plant (50 straw and 50 grains) samples were taken. The GLC-ECD chromatographic results indicated the following contamination levels distributed among soil, straw, and grains: HCB (0.7-1.2-0.7 microg.kg(-1)), alpha-HCH (0.6-3.4-1.2 microg.kg(-1)), gamma-HCH (1.8-27.3-4.4 microg.kg(-1)), Sigma-HCH (2.5-30.7-5.6 microg.kg(-1)), pp'DDE (1.0-7.8-5.5 microg.kg(-1)), op'DDT (16.1-20.4-17.0 microg.kg(-1)), pp'DDT (38.0-41.7-49.6 microg.kg(-1)), and Sigma-DDT (54.2-63.2-72.1 microg.kg(-1)). The study verified the presence of organochlorine pesticides in the Mexican agricultural environment and their migration from soil to the growing rye plants. However, DDT has been banned since 1999 for sanitary reasons, and Lindane is applied only in some cases as a seed dresser. The determined organochlorine pesticide levels in rye plants are low, at residual levels that are below Codex Alimentarius Commission maximum residue limits.

DDT↗

Need for an "integrated safety assessment" of GMOs, linking food safety and environmental considerations.

Evidence for substantial environmental influences on health and food safety comes from work with environmental health indicators which show that agroenvironmental practices have direct and indirect effects on human health, concluding that "the quality of the environment influences the quality and safety of foods" [Fennema, O. Environ. Health Perspect. 1990, 86, 229-232). In the field of genetically modified organisms (GMOs), Codex principles have been established for the assessment of GM food safety and the Cartagena Protocol on Biosafety outlines international principles for an environmental assessment of living modified organisms. Both concepts also contain starting points for an assessment of health/food safety effects of GMOs in cases when the environment is involved in the chain of events that could lead to hazards. The environment can act as a route of unintentional entry of GMOs into the food supply, such as in the case of gene flow via pollen or seeds from GM crops, but the environment can also be involved in changes of GMO-induced agricultural practices with relevance for health/food safety. Examples for this include potential regional changes of pesticide uses and reduction in pesticide poisonings resulting from the use of Bt crops or influences on immune responses via cross-reactivity. Clearly, modern methods of biotechnology in breeding are involved in the reasons behind the rapid reduction of local varieties in agrodiversity, which constitute an identified hazard for food safety and food security. The health/food safety assessment of GM foods in cases when the environment is involved needs to be informed by data from environmental assessment. Such data might be especially important for hazard identification and exposure assessment. International organizations working in these areas will very likely be needed to initiate and enable cooperation between those institutions responsible for the different assessments, as well as for exchange and analysis of information. An integrated assessment might help to focus and save capacities in highly technical areas such as molecular characterization or profiling, which are often necessary for both assessments. In the area of establishing international standards for traded foods, such as for the newly created Standards in Trade and Development Facility (STDF), an integrated assessment might help in the consideration of important environmental aspects involved in health and food safety. Furthermore, an established integrated view on GMOs may create greater consumer confidence in the technology.

Environment↗

Regional monitoring of lead and cadmium contamination in a tropical grazing land site, Thailand.

An investigation was carried out to monitor Pb and Cd contamination in grazing land located near a highway. Environmental media at different distances from highway (soil, grass, water, cow's forage, fertilizer, manure and milk samples) were collected from three sampling locations. Soil and grass were characterized by high metal mobility (soil with Pb: 5.25 +/- 0.71-14.59 +/- 1.17 mg kg(-1), dry mass and Cd: 0.038-0.33 +/- 0.04 mg kg(-1), dry mass and grass with Pb: 0.76 +/- 0.05-6.62 +/- 0.18 mg kg(-1), dry mass and Cd: 0.17+/- 0.01-0.73 +/- 0.09 mg kg(-1), dry mass). One-way analysis of variane (ANOVA) was applied to find out the correlation between metal (total and bioavailable) concentrations in the soil and the distance from roadside. In most cases, the finding showed that plants growing nearer to the highway are usually exposed to more heavy metal accumulations than those away from the highway. In addition, a correlation was established between plant available metal concentrations and plant metal uptake concentrations. Analysis of fertilizer and manure showed considerable amount of metals (fertilizer with Pb: 1.53 +/- 0.06 mg kg(-1) and Cd: 0.038 mg kg(-1) and manure with Pb: 2.55-3.34 mg kg(-1) and Cd: 0.14-0.31 mg kg(-1)). Long-.term simultaneous application of fertilizer and manure on the commercial farm showed higher metal accumulation in the soil and plants than those of co-operative farm. Considerable concentrations of metals (Pb: 1.60-2.94 mg kg(-1) and Cd: 0.025-0.19 mg kg(-1)) were observed in fodder. The finding clearly demonstrated that there are seasonal variation in total daily metal intake by individual cow (Pb: 109.37 mg day(-1) (dry), 273.47 mg day(-1) (rainy) and Cd: 2.02 mg day(-1) (dry), 19.62 mg day(-1) (rainy)). The provisional tolerable weekly intake of heavy metals in cows is 390 microg Pb and 28 microg Cd per kg body weight in the rainy season and 156 microg Pb and 2 microg Cd per kg body weight in the dry season. The levels of metals (Pb: 0.014 mg L(-1) and Cd: not detectable) and bio-transfer factor (10(-5)-10(-4)) in raw milk were found to be well below the Codex Alimentarius Commissions Draft (1997). Our analysis revealed that improvements on farm management give significant reduction in elevated levels of Pb and Cd in soil and plants, and however leads to minimize the amount of Pb and Cd in consumed milk.

Animal Feed↗

Enhancing pan-cancer spatial transcriptomics at single-cell resolution with stPainter.

Subcellular spatial transcriptomics can resolve tissue architecture at cellular scale, but sparse gene panels and limited detection sensitivity constrain downstream analysis. Existing enhancement methods often require tissue-matched single-cell RNA sequencing (scRNA-seq) references and dataset-specific retraining. Here we show that stPainter, a conditional generative model pretrained on a pan-cancer scRNA-seq atlas, can enhance spatial transcriptomics data without matched references or retraining. Using a latent diffusion architecture guided by Stochastic Differential Equations (SDE), stPainter&#xa0;reconstructs expanded expression profiles from sparse measurements and produces latent representations for clustering and cell-state analysis. When we apply stPainter&#xa0;upon 6 spatial transcriptomics datasets of different cancer types, we demonstrate that our model empowers downstream biological analyses, including fine-grained subpopulation clustering and pathway enrichment. Comparison with spatially resolved proteomics (CODEX) provided independent support for regional agreement between imputed cellular compositions and protein-level tissue organization. These results establish stPainter&#xa0;as a scalable approach for analyzing tumor microenvironments without auxiliary sequencing data.

Spatial Transcriptomics↗

An implementation of the HACCP system in the production of food-packaging material.

The Hazard Analysis Critical Control Point (HACCP) system according to the Codex Alimentarius model was applied to the processes of five paper and paperboard mills and four plants further converting paper or board intended for contact with foodstuffs. The generalised flow diagrams of the processes are presented. Each of the overall processes contained 40-150 process steps. Normally three to five sessions with HACCP teams and additional private negotiations were needed for each mill or plant. Hazards leading to critical control points (CCPs) were microbiological (handling/storage, circulation water, starch, process environment) and physical (process environment) in mills, and microbiological (storage, lacquers or glues, packaging and process environment), chemical (printing) and physical (storage of products, packaging and process environment) in plants. Specifications, critical limits (e.g., based on different kinds of reports and instructions), monitoring methods (microbiological and visual) and frequency, responsibilities and corrective actions of the processes are presented. Most of the improvements focused on improving the process environment. In five cases, hygiene training was included in the implementation of the HACCP system.

Food Packaging↗

Nutrition labelling: purpose, scientific issues and challenges.

Nutrition labels describe the nutrient content of a food and are intended to guide the consumer in food selection. The nutrition information provided must be selected on the basis of consistency with dietary recommendations. Selection of the specific nutrients or food components to be listed should further take into account label space, the analytical feasibility of measuring the particular nutritional component within the food matrix, and the relative costs of such analyses. Nutrition information provided on labels should be truthful and not mislead consumers. At the same time, labelling regulations should provide incentives to manufacturers to develop products that promote public health and assist consumers in following dietary recommendations. It is likely that in many countries, there would be some segments of the population that would benefit from information about the composition of foods. In these cases, countries should consider the need to provide for appropriate labelling and its presentation relative to existing guidelines and approaches. As nutrition-labelling efforts have evolved, different approaches and legal requirements have been established. These create difficulties in developing and harmonizing nutrition information listings, which have broad international applications. For these reasons, the Codex Guidelines on Nutrition Labeling play an important role to provide guidance to member countries when they want to develop or update their national regulations and to encourage harmonization of national standards with international standards. These Guidelines are based on the principle that no food should be described or presented in a manner that is false, misleading or deceptive. The Guidelines include provisions for voluntary nutrient declaration, calculation and presentation of nutrient information. The Guidelines on Claims establish general principles to be followed and leave the definition of specific claims to national regulations. Definitions are provided for a number of claims (nutrient content, comparative claims, nutrient function claims) as well as general requirements concerning consumer information in relation with claims. Nutrition labelling by itself cannot solve nutrition problems. It should be seen as one of the elements of nutrition policy and should be envisaged in the larger perspective of consumer education, which in its turn is part of an overall development policy. Exchange of information at the regional and subregional level is important, as each country can learn from the experience of others and regional co-ordination and co-operation can be developed.

Food Labeling↗

[The prohibition of lithotomy within the Hippocratic Oath: historical and ethical considerations on the history of surgery].

A passage with one of the most contradictory interpretations of the so-called Hippocratic Oath, which was presumably created between 500 and 300 before Christ, is the prohibition of lithotomy. The oldest handwritten traditions of the Hippocratic Oath are dating back to the 11th-12th century. However the section of the prohibition of lithotomy is missing in the oldest preserved tradition (Codex Urbinas gr. 64), which led to some authors interpretation of being added later on. Beyond all doubt the analysis of the texture of the Hippocratic Oath leads to the conclusion that the prohibition of bladder stone lithotomy must have been an integrative part of the oath from the very first beginning. The author could have been inspired by the following reasons to have a non oath related doctor let done the medical operation: the removal of a bladder stone by an operation, which was outfitted with many complications, was one of the most difficult surgical interventions in the antique. Celsus (1st century A. D.) mentioned "severe fever, urine fistula and deadly inflammations" after lithotomy. Since the operation was done perineally, presumably a negative sexual potency was feared. No doctor engaged to help and not to harm his patients was allowed to make this kind of operation, which was often followed by many complications. Nevertheless sometimes patients were "tantalised to death by suffering dreadful pain" through those bladder stone diseases. Consequently "practising men" (the term "surgeon" was created at a later date), those who had been specialised in that operation and had not been linked to the oath, were allowed to make this kind of dangerous operation. Due to a greater experience of those specialists (named as "Lithotomos" by Celsus ih the 1st century A. D.) the danger of this kind of operation was reduced. The prohibition of lithotomy could be interpreted as a commitment to realize the limits of ones own medical actions.

Cystostomy↗

Minerals and trace elements in total diets in The Netherlands.

1. During a period of 2.5 years, every 3 months 221 different food items forming a 'market basket' were purchased, prepared and divided into twenty-three food-commodity groups. The 'market basket' was based on a study of the dietary intake of 18-year-old male, Dutch adolescents. In the (homogenized) food groups various minerals and trace elements were determined. 2. The mean daily amounts of cadmium (21 micrograms), mercury (0.7 micrograms), lead (32 micrograms), tin (0.65 mg), arsenic (38 micrograms) and bromine (8 mg) in the diet of adolescents, as calculated from the concentrations analysed in the food groups, were all (well) below the Food and Agriculture Organization/World Health Organization acceptable daily intake (ADI) value (Codex Alimentarius Commission, 1984). 3. The mean daily amounts of zinc (14 mg) and selenium (72 micrograms) seemed to be adequate compared with the Dutch recommendations, (Voedingsraad (Dutch Nutrition Council) 1986). The amounts of copper (mean value 1.5 mg/d) and iron (mean value 14 mg/d) in the total diet were marginal. Contents of calcium (1340 mg/d), magnesium (433 mg/d) and iodine (402 micrograms/d) were all well above the Dutch recommendations for male adolescents. Sodium intake, corresponding to 11 g sodium chloride/d, was higher than advised. 4. It is concluded that the amounts of As, Br and toxic heavy metals in Dutch total-diet samples of male adolescents are of little concern as regards health aspects. Among the essential trace elements, Fe and Cu contents seem to be marginal. Some concern regarding the salt content is indicated.

Adolescent↗

Residue variability and sampling--practical problems and consequences for residues monitoring.

Data generated in the UK have indicated that pesticide residue levels can be highly variable between the individual fruit or vegetables from the same crop or lot in trade. Statistical experiments with these data showed that residues in composite samples, taken according to Codex recommendations, are unlikely to differ by more than a factor of 3-4 from the mean level in the lot. This was corroborated by results obtained from real composite samples. Many fruit or vegetables in trade are mixed after harvest to form combined lots. Analysis of composite samples provides a good indication of average residues but, where the lot has been mixed, such average values are potentially misleading. Residues monitoring is the best means available for general control of pesticide use and consumer exposure, but new strategies for sampling and analysis are required to address the combined effects of residues variability and mixing of lots.

Data Interpretation, Statistical↗

Ochratoxin A in Brazilian roasted and instant coffees.

Thirty-four samples of roast and ground coffee, 14 samples of instant coffee and two samples of decaffeinated instant coffee were collected in markets and supermarkets in the city of Campinas, Brazil, and analysed for ochratoxin A using immunoaffinity columns for clean-up and HPLC with fluorescence detection for quantification. The limit of detection was 0.2 ng/g ochratoxin A. Twenty-three samples of ground and roast coffee were found to be contaminated with the toxin at levels ranging between 0.3 and 6.5 ng/g. The average concentration in all 34 samples was 0.9 ng/g. All samples of instant coffee contained ochratoxin A at levels ranging from 0.5 to 5.1 ng/g, with an average figure of 2.2 ng/g. Roast and ground coffee is the type of coffee most used by Brazilians for the preparation of the beverage. Considering that an average Brazilian adult takes five cups of coffee per day, which corresponds to 30 g of roast and ground coffee, the probable daily intake of ochratoxin A by a 70 kg adult would be 0.4 ng/kg bw, which is far below the current Provisional Tolerable Daily Intake of 14 ng/kg bw for ochratoxin A as set by the Codex Alimentarius. To study the transfer of ochratoxin A into coffee brew, the beverage was prepared by two methods: (a) the drip method and (b) the Brazilian country style method. No significant difference was observed between the two methods in terms of extraction of the toxin using five contaminated samples containing between 0.8 and 6.5 ng/g ochratoxin A. The drip method extracted 86 +/- 15% and the Brazilian country style 74 +/- 20% of the ochratoxin A initially present in the roast and ground coffee.

Brazil↗

Three-year study of fenthion and dimethoate pesticides in olive oil from organic and conventional cultivation.

Residues of fenthion and dimethoate pesticides were determined in organic and conventional olive oils by liquid-liquid and solid-phase extractions with subsequent gas chromatography and mass spectrometric analysis. The olive oil samples were collected from Crete during 1997-99. The average concentrations of fenthion in conventional olive oils were 0.1222, 0.145 and 0.1702 mg x kg(-1), and for dimethoate were 0.0226, 0.0264 and 0.0271 mg x kg(-1) for 1997, 1998 and 1999, respectively. The average concentrations of fenthion in organic olive oils were 0.0215, 0.0099 and 0.0035 mg x kg(-1) for 1997, 1998 and 1999, while for dimethoate they were 0.0098, 0.0038 and 0.0010 mg x kg(-1), respectively. All the olive oils contained residue levels lower than the maximum residue levels according to the FAO/WHO Codex Alimentarius. The organic olive oil contained significantly lower concentrations of the two pesticides. The levels of fenthion and dimethoate in organic olive oils exhibited a decreasing trend following the implementation of the new cultivation method. We propose procedures that should be established in the organic cultivation in order to maximize its effectiveness.

Dimethoate↗

Determination of polydimethylsiloxanes by 1H-NMR in wine and edible oils.

Fourier transform (1)H-nuclear magnetic resonance (NMR) spectroscopy was suitable for the quantitative determination of polydimethylsiloxanes (PDMS) in wine and edible oil samples. This approach offers highly specific qualitative and quantitative analysis due to silicone-specific location of proton signals linked to carbon atoms located directly next to silicon atoms (0-0.5 ppm), as well as a different location of signals in the range for different organosilicon structures. The method can be used for the control of PDMS at regulatory limits in foodstuffs (10 mg kg(-1)) using hexamethyldisiloxane (HDMS) as an internal standard. Samples were prepared by extraction under suitable conditions to separate the analyte, and with analyte enrichment before (1)H-NMR analysis. Analytical procedures were developed to permit the determination of PDMS at 0.06 mg kg(-1) in wine and at 6 mg kg(-1) in edible oils samples using readily available NMR instrumentation. It was, however, possible to lower the limit of detection to 6 microg kg(-1) for wine and to 60 microg kg(-1) for edible oils using a higher field instrument (500 MHz). Relative standard deviations (S(r)) were obtained for wine (0.028) and for oil samples (0.043), which when compared with values obtained for samples spiked with PDMS (0.021) indicated that the sample preparation was the main factor determining the precision of the method. The average recovery rates for PDMS were 97 and 95% for wine and edible oils, respectively. PDMS was detected in four brands of Italian wine, with Chianti-Rafaello containing the highest concentration (0.35 mg kg(-1)), and in four types of edible oils, highest concentration (11.9 mg kg(-1)) being found in Italian corn oil. None of the levels of PDMS found in the food samples exceeded the permissible standards laid down by the Codex Alimentarius Commission (10 mg kg(-1)), with the exception of the one corn oil sample.

Dimethylpolysiloxanes↗

Residues of DDT and HCH pesticides in rice samples from different geographical regions of India: a multicentre study.

As part of a multicentre study conducted by the Indian Council of Medical Research, 2000 samples of rice were collected from rural and urban areas of 13 states representing different geographical regions of India. The samples were analyzed for residues of DDT [2,2-bis(p-chlorophenyl)-1,1,1-trichloroethane] and different isomers of HCH [1,2,3,4,5,6-hexachlorocyclohexane, a mixture of isomers] by gas-chromatography. Residues of DDT and HCH, respectively, were detected in about 58 and 73% of the samples analysed. Medians of both DDT and HCH in rice samples were around 0.01 mg kg (-1). Concentrations of alpha-, beta-, gamma- and delta-HCH exceeded a maximum residue limit of 0.05 mg kg (-1) for each isomer in rice fixed by the Ministry of Health and Family Welfare of the Indian Government in 4.3, 2.6, 1.7 and 1.2% of the samples, respectively. There is no statutory limit fixed in India for DDT residues in cereals. Its maximum residue limit of 0.1 mg kg (-1) in cereals recommended by Codex was exceeded by about 2% of the samples examined. Estimated intake of DDT and isomers of HCH through consumption of rice contaminated at their median and 90th percentiles constituted a small proportion of their acceptable daily intakes.

Chromatography, Gas↗

Norwegian monitoring programme on the inorganic and organic contaminants in fish caught in the Barents Sea, Norwegian Sea and North Sea, 1994-2001.

The results from part of a monitoring programme of contaminant levels in fish and other seafood products initiated by the Directorate of Fisheries in Norway in 1994 are presented. Concentrations of 22 elements (four are presented here: As, Cd, Hg and Pb) and HCB, HCH, PCB 28, 52, 101, 105, 118, 138, 153, 156, 180, pp-DDD, p-DDE, p-DDT, sum DDT and (137)Cs were determined in 17 species of fish caught in three sampling locations: the Barents Sea, the Norwegian Sea and the North Sea. The fish species analysed in the survey were limited to species of commercial importance for Norway with catching volumes of at least 10,000 metric tons year(-1). The survey started in 1994 and is expected to continue beyond 2010. The analyses were carried out on 25 individual fish from each species and each sampling location, and the locations were representative of commercial fishing grounds for the species in question. The concentrations of contaminants found were considerably lower than the maximum levels permissible in fish set by CODEX and the European Union for contaminants in seafood products.

Animals↗

Joint IDF-IUPAC-IAEA(FAO) interlaboratory validation for determining aflatoxin M1 in milk by using immunoaffinity clean-up before thin-layer chromatography.

A collaborative study was conducted under the auspices of the International Dairy Federation (IDF), the International Union of Pure and Applied Chemistry (IUPAC) and the International Atomic Energy Agency (IAEA), a collaborative Food and Agricultural Organization (FAO) body fully to validate a method combining immunoaffinity clean-up to thin-layer chromatography for the determination of aflatoxin M(1) in milk. Work was done in order to afford those laboratories not equipped with high-performance liquid chromatography, mainly from developing countries, with a simplified but fully validated method as an alternative to the European validated immunoaffinity-high performance liquid chromatography method published as an EN ISO Standard 14501, February 1999. The validation study was carried out on samples of aflatoxin M(1)-contaminated milk and milk powder at levels close to the tolerable level of 0.5 microg l(-1) as recommended by the Codex Alimentarius and to the regulatory level of 0.05 microg l(-1) as laid down by the European Commission. Fourteen laboratories representing 11 countries participated in the trial. The relative standard deviations for repeatability and reproducibility based on raw data were in the range 27-48 and 35-54%, respectively. The recovery rate varied from 32 to 120%. The mishandling of two crucial steps of the protocol such as matrix sample reconstitution and extract evaporation could explain the wide variation of the recovery rate. For this reason, data were then corrected for recovery. Consequently, the relative standard deviations for repeatability and reproducibility were recalculated after correction for recovery and were in the range 26-54 and 34-53%, respectively. The method will be published as a standard ISO/DIS 14674--IDF 190.

Aflatoxin M1↗