Evaluation of certain food additives and contaminants

This report represents the conclusions of a Joint FAO/WHO Expert Committee convened to evaluate the safety of various food additives, including flavouring agents, with a view to recommending acceptable daily intakes (ADIs) and to preparing specifications for identity and purity. The Committee also evaluated the risk posed by two food contaminants, with the aim of advising on risk management options for the purpose of public health protection. The first part of the report contains a general discussion of the principles governing the toxicological evaluation and assessment of intake of food additives (in particular flavouring agents) and contaminants. A summary follows of the Committee's evaluations of technical, toxicological and intake data for certain food additives (acidified sodium chlorite, asparaginase from Aspergillus oryzae expressed in Aspergillus oryzae, carrageenan and processed Eucheuma seaweed, cyclotetraglucose and cyclotetraglucose syrup, isoamylase from Pseudomonas amyloderamosa, magnesium sulfate, phospholipase A1 from Fusarium venenatum expressed in Aspergillus oryzae, sodium iron(III) ethylenediaminetetraacetic acid (EDTA) and steviol glycosides); eight groups of related flavouring agents (linear and branched-chain aliphatic, unsaturated, unconjugated alcohols, aldehydes, acids and related esters; aliphatic acyclic and alicyclic terpenoid tertiary alcohols and structurally related substances; simple aliphatic and aromatic sulfides and thiols; aliphatic acyclic dials, trials and related substances; aliphatic acetals; sulfur-containing heterocyclic compounds; aliphatic and aromatic amines and amides; and aliphatic alicyclic linear alpha, beta -unsaturated di- and trienals and related alcohols, acids and esters); and two food contaminants (aflatoxin and ochratoxin A). Specifications for the following food additives were revised: maltol and ethyl maltol, nisin preparation, pectins, polyvinyl alcohol, and sucrose esters of fatty acids. Specifications for the following flavouring agents were revised: maltol and ethyl maltol, maltyl isobutyrate, 3-acetyl-2,5-dimethylfuran and 2,4,5-trimethyl-delta-oxazoline (Nos 1482, 1506 and 1559), and monomenthyl glutarate (No. 1414), as well as the method of assay for the sodium salts of certain flavouring agents. Annexed to the report are tables summarizing the Committee's recommendations for intakes and toxicological evaluations of the food additives and contaminants considered.     

钩端螺旋体重组DNA探针对致病性黄疸出血群钩体DNA的杂交识别

作者从建立的黄疸出血群钩端螺旋体(下称钩体)DNA基因库中筛选出重组DNA克隆PLIps01(15kb)和PLIEc34(4kb)制备成~(32)P放射性探针。以该二探针对致病性黄疸出血群所属血清型的13个菌株钩体DNA进行Southern印迹分析,结果表明,该二DNA探什对黄疸出血群各株钩体DNA具有强烈的特异性结合,能识别出简洁的DNA带型,并能区分不同血清型以至菌株的DNA带型差别。作者认为,钩体DNA重组探什结合Southern印迹分析是一种灵敏而特异的检测分析方法,可作为诊断、鉴定和分析钩体的工具。     

Continued evolution of highly pathogenic avian influenza A (H5N1): updated nomenclature

Please cite this paper as: WHO/OIE/FAO. (2012) Continued evolution of highly pathogenic avian influenza A(H5N1): Updated nomenclature. Influenza and Other Respiratory Viruses 6(1), 1–5. Background Continued evolution of highly pathogenic avian influenza A (H5N1) throughout many regions of the eastern hemisphere has led to the emergence of new phylogenetic groups. A total of 1637 new H5N1 hemagglutinin (HA) sequences have become available since the previous nomenclature recommendations described in 2009 by the WHO/OIE/FAO H5N1 Evolution Working Group. A comprehensive analysis including all the new data is needed to update HA clade nomenclature. Methods Phylogenetic trees were constructed from data sets of all available H5N1 HA sequences. New clades were designated on the basis of phylogeny and p‐distance using the pre‐established nomenclature system (Emerg Infec Dis 2008; 14:e1). Each circulating H5N1 clade was subjected to further phylogenetic analysis and nucleotide sequence divergence calculations. Results All recently circulating clades (clade 1 in the Mekong River Delta, 2.1.3 in Indonesia, 2.2 in India/Bangladesh, 2.2.1 in Egypt, 2.3.2, 2.3.4 and 7 in Asia) required assignment of divergent HA genes to new second‐, third‐, and/or fourth‐order clades. At the same time, clades 0, 3, 4, 5, 6, 8, 9, and several second‐ and third‐order groups from clade 2 have not been detected since 2008 or earlier. Conclusions New designations are recommended for 12 HA clades, named according to previously defined criteria. In addition, viruses from 13 clades have not been detected since 2008 or earlier. The periodic updating of this dynamic classification system allows continued use of a unified nomenclature in all H5N1 studies.     

Innovative Solutions Using Zygoma Implants

The severely resorbed edentulous maxilla presents significant treatment challenges. The introduction of remote implant support using zygoma implants has provided a plethora of treatment possibilities for many patients. This article presents four very different sets of circumstances successfully treated using this protocol.     

Evaluation of certain veterinary drug residues in food. Sixty-sixth report of the Joint FAO/WHO Expert Committee on Food Additives

This report represents the conclusions of a Joint FAO/WHO Expert Committee convened to evaluate the safety of residues of certain veterinary drugs in food and to recommend maximum levels for such residues in food. The first part of the report considers general principles regarding the evaluation of veterinary drugs within the terms of reference of JECFA, including compounds without an ADI or MRL; recommendations on principles and methods in derivation of MRLs, including a new procedure for estimating chronic dietary intakes; the use of a spreadsheet-based procedure for the statistical evaluation of residue depletion data; a revised approach for the derivation of microbiological ADIs; and the Committee's review of and comments on documents provided by the Codex Committee on Residues of Veterinary Drugs. Summaries follow of the Committee's evaluations of toxicological and residue data on a variety of veterinary drugs: three antimicrobial agents (colistin, erythromycin, flumequine), two production aids (melengestrol acetate, ractopamine hydrochloride), an insecticide (trichlorfon (metrifonate)) and an anthelminthic (triclabendazole). In addition, the attempt by the Committee to use tylosin as an example to investigate if evaluations are possible based on published data in the absence of data submissions from sponsors is described. Annexed to the report is a summary of the Committee's recommendations on these drugs, including acceptable daily intakes and proposed maximum residue limits.     

Evaluation of certain food additives and contaminants

This report represents the conclusions of a Joint FAO/WHO Expert Committee convened to evaluate the safety of various food additives with a view to recommending acceptable daily intakes (ADIs) and to preparing specifications for identity and purity. The Committee also evaluated the risk posed by a number of food contaminants, with the aim of advising on risk management options for the purpose of public health protection. The first part of the report contains a general discussion of the principles governing the toxicological evaluation and assessments of intake of food additives (in particular, flavouring agents) and contaminants. A summary follows of the Committee's evaluations of technical, toxicological and intake data for certain food additives (annatto extracts, natamycin, propyl paraben, synthetic lycopene and lycopene from Blakeslea trispora and food contaminants (aluminium, 3-chloro-1,2-propanediol, 1,3-dichloro-2-propanol and methylmercury). Specifications for the following food additives were revised: carob bean gum, guar gum, titanium dioxide and zeaxanthin. Annexed to the report are tables summarizing the Committee's recommendations for intakes and toxicological evaluations of the food additives and contaminants considered.     

Protein and amino acid requirements in human nutrition

The World Health Organization and the Food and Agriculture Organization have worked to quantify the energy and nutrient needs of populations since 1949. This is the latest in a series of reports that aim to provide: updates on protein and amino acid requirements in health and disease for all age groups and pregnant and lactating mothers; recommendations on protein requirements in health and disease, including their implications for developing countries; recommendations on protein quality and labelling for worldwide use. This report provides the tools to address practical questions on the adequacy of food supplies, targets for food and nutrition policy, and labelling of protein quality. It contains specific recommendations for infant, child and adult nutrition. This report is an essential reference for those who need to determine the adequacy of population food intakes; set national food and nutrition guidelines and regulations on the protein and amino acid content of industrially processed foods; determine nutrient needs, and evaluate and ensure the adequacy of rations for vulnerable groups. The tools in this report can also be used to map and monitor global food shortages and under-nutrition through early warning systems.     

Guidelines for predicting the dietary intake of pesticide residues

These guidelines have been developed to describe procedures for predicting the dietary intake of pesticide residues, and will assist national authorities in their considerations of the acceptability of the Codex maximum residue limits (MRLs). The relevant authorities are invited to consider the basic approaches described in these guidelines, which have been designed to provide reasonable assurance that such MRLs would not result in dietary intakes that exceed the acceptable daily intake (ADI) of a pesticide.