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1.
On 30 June 2011, the European Chemicals Agency published two reports, one on the functioning of the REACH system, the other on the use of alternatives to animal testing in compliance with that system. The data presented are based on information gained during the first registration period under the REACH system, which included high production volume chemicals and substances of very high concern, which have the most extensive information requirements. A total of 25,460 registration dossiers were received, covering 3,400 existing, so-called 'phase-in', substances, and 900 new, so-called 'non-phase-in', substances. Data sharing and the joint submission of data are reported to have worked successfully. In the registration dossiers for these substances, results from new animal tests were included for less than 1% of all the endpoints; testing proposals (required for 'higher-tier' information requirements) were submitted for 711 in vivo tests involving vertebrate animals. The registrants mainly used old, existing experimental data, or options for the adaptation (waiving) of information requirements, before collecting new information. For predicting substance toxicity, 'read-across' was the second most-used approach, followed by 'weight-of-evidence'. In vitro toxicity tests played a minor role, and were only used when the respective test methods had gained the status of regulatory acceptance. All in all, a successful start to the REACH programme was reported, particularly since, in contrast to most predictions, it did not contribute to a significant increase in toxicity testing in animals.  相似文献   

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3.
The hedonic thresholds methodology was recently proposed which allows for determination of two new sensorial thresholds, the compromised acceptance threshold and the hedonic rejection threshold (HRT). For a new methodology to be accepted by the scientific community, its ability to produce reliable results must be demonstrated. Thus, this study sought to validate this new methodology when used to calculate the HRT. In order to do so, the analytical performance indices of precision (repeatability, intermediate precision, and reproducibility), accuracy and robustness for the results for the HRT calculation were measured. The results of seven experiments demonstrated that the methodology possesses high repeatability, intermediate precision and robustness, and satisfactory accuracy and reproducibility. It was therefore concluded that the HRT determination methodology satisfactorily met the analytical performance criteria evaluated, therefore generating reliable results.

Practical applications

The hedonic thresholds methodology (HTM) has numerous applications, including the application of a more severe thermal treatment to obtain greater microbial or enzymatic inactivation, the determination of food shelf life based on its sensory acceptance, the reduction of specific, expensive ingredients in food formulations, reduction of ingredients that are harmful to health when consumed in excess (e.g., sucrose, sodium, and fat), determination of the maximum “defect” threshold that may be present in food and others. The HTM is a recently proposed methodology; therefore, the reliability of the values of the hedonic rejection threshold must be validated, calculated via the HTM. Reliability of the HRT results was confirmed when HTM validation was performed. Thus, the methodology can undoubtedly be applied for the intended purpose.  相似文献   

4.
Guidelines for the registration of entomogenous fungi as insecticides   总被引:1,自引:0,他引:1  
Guidelines have been formulated for registration of entomogenous fungi. It is recommended that producers wishing to register a mycoinsecticide supply detailed information concerning the basic biology, host range and characterization of the strain involved as well as details of the manufacturing, quality control, use, field application, efficacy and safety of the pathogen. The recommendations for safety-testing to warm-blooded animals are arranged in a 3-tier system to facilitate decision making for registration authorities. The safety protocols include infection, toxicity, allergenicity and mutagenicity tests. Recommendations are also made to monitor possible effects on people who handle the product during manufacture or application. Information on the activity of the fungus to plants and non-target vertebrates and invertebrates is also required.  相似文献   

5.
Lactobacilli have played a crucial role in the production of fermented products for millennia. Their probiotic effects have recently been studied and used in new products. Isolated cases of lactobacillemia have been reported in at-risk populations, but lactobacilli present an essentially negligible biological risk. We analyzed the current European guidelines for safety assessment in food/feed and conclude that they are not relevant for the Lactobacillus genus. We propose new specific guidelines, beginning by granting a 'long-standing presumption of safety' status to Lactobacillus genus based on its long history of safe use. Then, based on the available body of knowledge and intended use, only such tests as are useful will be necessary before attributing 'qualified presumption of safety' status.  相似文献   

6.
The unique and complex nature of biotechnology-derived pharmaceuticals has meant that it is often not possible to follow the conventional safety testing programs used for chemicals, and hence they are evaluated on a case-by-case basis. Nonclinical safety testing programs must be rationally designed with a strong scientific understanding of the product, including its method of manufacture, purity, sequence, structure, species specificity, pharmacological and immunological effects, and intended clinical use. This knowledge, coupled with a firm understanding of the regulatory requirements for particular product types, will ensure that the most sensitive and regulatory-compliant test systems are used to optimize the chances of gaining regulatory approval for clinical testing or marketing authorization in the shortest possible time frame.  相似文献   

7.
In 1990 a new approach for vaccination was invented involving injection of plasmid DNA in vivo, which elicits an immune response to the encoded protein. DNA vaccination can overcome most disadvantages of conventional vaccine strategies and has potential for vaccines of the future. However, today 15 years on, a commercial product still has not reached the market. One possible explanation could be the technique's failure to induce an efficient immune response in humans, but safety may also be a fundamental issue. This review focuses on the safety of the genetic elements of DNA vaccines and on the safety of the microbial host for the production of plasmid DNA. We also propose candidates for the vaccine's genetic elements and for its microbial production host that can heighten the vaccine's safety and facilitate its entry to the market.  相似文献   

8.
FDA oversight of medical devices, including in vitro diagnostic devices (IVDs or laboratory tests), in the United States was a direct result of the passage of the Medical Device Amendments of 1976. This law introduced a series of general controls for medical devices including registration and listing, requirements for production using good manufacturing practices, and requirements for post-market reporting of device failures. This produced for the first time a menu of laboratory tests on the market, a system to ensure these were produced consistently over time, and a mechanism for FDA to identify problems with device use and to work with companies to ensure corrective action. This law also introduced the requirement for premarket review of new versions of old devices and of fundamentally new medical devices.  相似文献   

9.
Recent advances in molecular biology, immunology, microbiology, genetics and microbial pathogenesis have lead to the development of a wide variety of new approaches for developing safer and more effective vaccines based on designs such as subunit vaccines, gene deleted vaccines, live vectored vaccines, and DNA mediated vaccines. Technology tools can be as basic as identifying naturally occurring strains with deletions that support differentiating infected from vaccinated animal (DIVA) needs or be based on higher technology developments such as improved protein expression and purification methods, transgenic plant- and plant virus-based antigen production, and novel adjuvants that target specific immune responses. These new approaches, when applied to the development of marker vaccines and companion diagnostic test kits hold tremendous potential for developing improved tools for eradication and control programs. Marker vaccines and companion diagnostic test kits must meet the established licensing requirements for purity, potency, safety and efficacy. Efficacy claims are based on evaluation of the level of protection demonstrated in host animal trials and may range from "prevents infection with (a specific agent)", to "for use as an aid in the reduction of disease due to (a specific agent)." The differences in claims and recommendations are a function of the variation in protection elicited by various vaccines. For designing effective eradication programs, vaccine efficacy characteristics such as for reducing susceptibility to infections and spread of infections must be well defined; similarly, diagnostic test performance characteristics (efficacy) must be determined. In addition to data to support efficacy claims, it is imperative that safety of production and use of vaccines be evaluated. During the design of marker vaccines and diagnostic tests, it is important to consider the application of appropriate technologies to improve the safety of these products. Use of recombinant technologies for production of vaccines and/or diagnostic test antigens can reduce the biosafety concerns during production and during use, including human exposure to zoonotic pathogens during production and use, and potential spread of foreign animal disease agents due to loss of biocontainment. In addition, vaccines may induce adverse reactions. It is important to determine the frequency of adverse events and to reduce the likelihood of induction of adverse reactions through proper design.  相似文献   

10.
Quality control in the production of an immunoglobulin for intravenous use   总被引:1,自引:0,他引:1  
A Gardi 《Blut》1984,48(6):337-344
This paper briefly surveys the control measures and tests which are carried out before, during and after manufacture of an i.v. immunoglobulin in order to assure the quality of the preparation. The quality requirements are determined by both the standards expected by physicians and patients and by the specifications of the registration authorities in the various countries. A great deal of know-how and considerable technical investment is required to match these requirements. Furthermore a comprehensive quality assurance programme is compulsory: It begins with the careful collection and analysis of each single blood donation, continues through all the manufacturing stages and ends with the rigorous testing of every batch of the end product - an examination comprising 23 different tests.  相似文献   

11.
微生物是人类赖以生存的重要资源,为提高微生物的生产效率或者赋予其新的生物学功能,需要通过理化方法进行诱变或通过分子生物学技术对其进行定点突变。在目前的理化诱变方法中,常压室温等离子(atmospheric and room temperature plasma,ARTP)诱变技术具有操作简单、条件温和、安全性高、诱变快速等优点,成为倍受青睐的新方法。基于此,综述了ARTP诱变技术的原理及其在微生物诱变育种方面的应用,以期为选育性能优越的微生物菌种的诱变育种相关研究提供借鉴。  相似文献   

12.
Constraints about the use of chemical insecticides have limited the availability of control measures against soil-borne insect pests. Entomopathogenic nematodes of the genera Steinernema and Heterorhabditis provide an environmentally safe and economically reasonable alternative. Their life cycle and current production, storage and formulation technology are described. An overview of their safety, use in integrated pest management and current market potential (US$10 million in 1994) is also given. The costs of research and development efforts and the scale-up of production technologies are discussed in relation to the current and future market potential. Large-scale, outdoor application will require additional scientific and technical progress in the areas of production, storage, formulation and application. Besides public funding, the current niche markets will need to provide the financial basis for further development, provided that regulatory conditions will not limit the exploitation of the nematodes' market potential. It is recommended that nematodes should be exempted from registration. Rules for risk assessment in the use of exotic nematodes should be internationally harmonized and related specifically to the biology and ecology of these nematodes. The volume of current markets would not justify the costs of registration procedures currently required for chemical or microbial insecticides or genetically engineered organisms. Regulatory policies should aim at supporting the further introduction of entomopathogenic nematodes as biocontrol agents.  相似文献   

13.
Application of rRNA-targeted oligonucleotide probes in biotechnology   总被引:4,自引:0,他引:4  
Ribosomal RNA-targeted oligonucleotide probes have become valuable tools for the detection of microorganisms involved in important biotechnological processes. Microorganisms which are of major importance for processes such as wastewater treatment, microbial leaching or methane production can be detected and quantified in situ within a complex microbial community. For certain processes, such as nitrification or biological phosphate removal, new microorganisms have become the focus of interest and have led to an improved understanding of these bioremediation techniques. Hybridization techniques have become fast and reliable alternatives to conventional cultivation techniques in the food industry as a control method for starter cultures for fermentation processes or product control. Recent analytical tools such as flow cytometry and digital image processing have improved the efficiency of these techniques. This review is intended to present a summary of methodological aspects of rRNA-based hybridization techniques and their application in biotechnology.  相似文献   

14.
Bioprocessing for biofuels   总被引:1,自引:0,他引:1  
While engineering of new biofuels pathways into microbial hosts has received considerable attention, innovations in bioprocessing are required for commercialization of both conventional and next-generation fuels. For ethanol and butanol, reducing energy costs for product recovery remains a challenge. Fuels produced from heterologous aerobic pathways in yeast and bacteria require control of aeration and cooling at large scales. Converting lignocellulosic biomass to sugars for fuels production requires effective biomass pretreatment to increase surface area, decrystallize cellulose and facilitate enzymatic hydrolysis. Effective means to recover microalgae and extract their intracellular lipids remains a practical and economic bottleneck in algal biodiesel production.  相似文献   

15.
Microorganisms are enormous but largely untapped natural resources for biological control of pests and diseases. There are two primary reasons for their underployment for pest or disease control: (1) the technical difficulties of using microorganisms for biological control, owing to a lack of fundamental information on them and their ecology, and (2) the costs of product development and regulatory approvals required for each strain, formulation, and use. Agriculture and forestry benefit greatly from the resident communities of microorganisms responsible for naturally occurring biological control of pest species, but additional benefits are achieved by introducing/applying them when or where needed. This can be done as (1) an inoculative release, (2) an augmentative application, or (3) an inundative application. Because of their specificity, different microbial biocontrol agents typically are needed to control different pests or the same pest in different environments. Four potential adverse effects are identified as safety issues (hazards) associated with the use of microorganisms for the biological control of plant pests and diseases. These are: (1) displacement of nontarget microorganisms, (2) allergenicity to humans and other animals, (3) toxigenicity to nontarget organisms, and (4) pathogenicity to nontarget organisms. Except for allergenicity, these are the same attributes that contribute to the efficacy of microbial biocontrol agents toward the target pest species. The probability of occurrence of a particular adverse nontarget effect of a microbial biocontrol agent may be a function of geographic origin or a specific trait genetically added or modified, but the safety issues are the still the same, including whether the microorganism intended for pest or disease control is indigenous, nonindigenous (imported and released), or genetically modified by traditional or recombinant DNA (rDNA) technology. Likewise, the probability of occurrence of a particular adverse nontarget effect may vary with method of application, e.g., whether as an aerosol, soil treatment, baits, or seed treatment, and may increase with increased scale of use, but the safety issues are still the same, including whether the microorganism is used for an inoculative release or augmentative or inundative application. Existing practices for managing microorganisms in the environment (e.g., plant pathogens,Rhizobium,plant inoculants) provide experience and options for managing the risks of microorganisms applied for pest and disease control. Moreover, experience to date indicates that any adverse nontarget effects, should they occur, are likely to be short-term or transitory effects that can, if significant, be eliminated by terminating use of the microbial biocontrol agent. In contrast, production agriculture as currently practiced, such as the use of tillage and crop rotations, has significant and long-term effects on nontarget organisms, including the intentional and unintentional displacement of microorganisms. Even the decision to leave plant pests and diseases unmanaged could have significant long-term environmental effects on nontarget organisms. Potential safety issues associated with the use of microbial biocontrol must therefore be properly identified and compared with the impact of other options for managing the pest or leaving the pest unmanaged. This paper provides a scientific framework for this process.  相似文献   

16.
Microbial pathogens continue as major threats to health. Indeed, many ongoing societal changes are enhancing our vulnerability and exposure to several frank and opportunistic pathogens. This, together with rampant antimicrobial resistance and reduced prospects for newer drugs and vaccines, is forcing a higher reliance on microbiocides in infection prevention and control. That this reliance may not be well-founded becomes apparent from a closer look at current ways of testing and registering microbiocides, their label claims as well as human and environmental safety of certain widely used microbicidal chemicals. Many methods to test microbiocides for registration are flawed and/or entail test conditions irrelevant to field use. Pathogens listed on product labels may not be among those amenable to interruption through microbiocide use. The wide variations and discrepancies in existing national/regional regulations for registering microbiocides for sale stifle innovation. This is a critical look at the above-mentioned issues with emphasis on chemicals meant for use on environmental surfaces and medical devices. It highlights better ways to test microbiocides and to attain global harmonization of testing and product registration. It also details the known and potential dangers of microbiocide use and what to consider in choosing such formulations for optimal safety and effectiveness. End users are advised to be more critical and prudent in the selection and application of microbicidal chemicals, manufacturers are encouraged to explore infection control products and technologies that are safer in the workplace and for the environment, and regulators are urged to review and update the requirements and procedures for premarket review of microbiocide efficacy data and label claims. Independent investigations are also urgently needed to document the proportion of nosocomial infections that would be amenable to prevention through chemical disinfection of environmental surfaces.  相似文献   

17.
An essential feature of the production of all microbial control agents is an effective quality control system. Well-defined product specifications with accompanying quality control procedures help to maximize product performance, ensure product safety, standardize manufacturing costs and reduce the risks of supply failure, thus building user confidence. A production system that does not have a quality control system is one whose output is uncontrolled and a lack of thorough quality feedback can result in batches of product with variable concentrations of active agent. This results in products with variable performance leading to control failures by users and serious loss of user confidence. Strict quality control procedures are not only essential for product consistency, but also for safety. Where quality control is inadequate, microbial contamination of the final product is inevitable. In most of such cases this will merely lead to a loss of efficacy due to dilution of the active ingredient by competing microorganisms, but also the potential of producing human pathogens must be ruled out. Recognition of contaminants and quantification of the degree of contamination are therefore important in determining any possible risk to human health. Many low technology production systems in use around the world have minimal or no quality control procedures. This is unacceptable and can damage the reputation of microbial control in addition to possibly posing health risks to those that produce or are exposed to the product. Two case studies from developing countries, are used to illustrate how the lack of quality control procedures can lead to the production of low viability, highly contaminated products with low or negligible concentrations of the active ingredient. However, it is also demonstrated that low technology production systems in developing countries can produce high quality products, provided appropriate quality control procedures are firmly implemented. It must be recognized that quality control procedures can be more complex and technologically demanding than the production procedures themselves, but it is largely on the effectiveness of these control procedures that the long-term acceptability of fungal and viral products depends. This paper details the quality control procedures considered necessary in the mass production of fungi and viruses for use as biocontrol agents, and attempts to suggest reasonable standards that can be achieved by all producers.  相似文献   

18.
Standardization of acellular pertussis vaccines.   总被引:1,自引:0,他引:1  
In comparison with the current whole cell pertussis vaccine, the new generation of acellular pertussis vaccines opens new opportunities to improve the standardization of the product, because well defined and characterized components are used in these new products.However, different compositions, purification and inactivation methods are used by different manufacturers. Consequently the various acellular pertussis vaccines in the world are difficult to compare in a meaningful manner using simple laboratory tests. In addition, the absence of a reliable animal model and serological correlates with protection in children are other complicating factors.For that reason it seems that the consistency in manufacturing based on a clinically validated production process is the best way to ensure the safety and efficacy of routinely produced acellular pertussis vaccines.Laboratory tests to monitor the antigen content, purity, safety and immunogenicity seem to be the best approach to standardize this new generation of pertussis vaccines against homologous standard vaccines with known clinical efficacy and safety and to support the consistency in manufacture.  相似文献   

19.
Soil microbial toxicity tests are seldom used in ecological risk assessments or in the development of regulatory criteria in the U.S. The primary reason is the lack of an explicit connection between these tests and assessment end-points. Soil microorganisms have three potential roles with respect to ecological assessment endpoints: properties of microbial communities may be end-points; microbial responses may be used to estimate effects on plant production; and microbial responses may be used as surrogates for responses of higher organisms. Rates of microbial processes are important to ecosystem function, and thus should be valued by regulatory agencies. However, the definition of the microbial assessment endpoint is often an impediment to its use in risk assessment. Decreases in rates are not always undesirable. Processes in a nutrient cycle are particularly difficult to define as endpoints, because what constitutes an adverse effect on a process is dependent on the rates of others. Microbial tests may be used as evidence in an assessment of plant production, but the dependence of plants on microbial processes is rarely considered. As assessment endpoints are better defined in the future, microbial ecologists and toxicologists should be provided with more direction for developing appropriate microbial tests.  相似文献   

20.
Evaluating cell substrates for producing vaccines and other biologicals is one of the critical aspects in assuring quality and safety of these products. As part of its mission in setting standards for biological products, WHO provides recommendations for manufacturing and evaluating biologicals. Regular updates of the guidance documents are important to manufacturers and regulators worldwide. WHO Expert Committee on Biological Standardization (ECBS) identified a need for revising the requirements for cell substrates (WHO TRS 878, annex 1). In response, WHO established a Study Group (SG) in 2006 that prepared an updated set of recommendations for using cell substrates for the production of biologicals. A summary of the proposed changes that the SG made in 2007 is available at WHO web site (http://www.who.int/biologicals/publications/meetings/areas/vaccines/cells/en/index.html). Draft revised recommendations were circulated to regulators, manufacturers and other experts for comments in April 2009.The SG held its third meeting on 22–23 April 2009 to review progress in the revision and to propose further improvements. In addition, the experts discussed the need for reference preparations, reference cell banks, and standardization of testing methodologies. The SG proposed clarifications of the rationale for in vivo testing as well as the potential for applying new methods for in vitro testing for detecting microbial agents. In line with this, WHO should conduct review of the current manufacturers' practice in using tests for microbial agents and interpreting these results. Additionally, WHO should take a lead in developing an International Standard for nucleic acid amplification test (NAT) for detecting mycoplasma contamination in cell substrates. WHO Collaborating Centers will lead this initiative, involving other relevant institutions in this area. Finally, advice on the replacement of the WHO Vero reference cell bank 10–87 with respect to the source of cells and re-characterization of the bank was provided. The intended use of the replacement cell bank would be the same as for the current cell bank, which is to serve as a source of well-characterized cells for establishing master cell banks for the production of biologicals. The SG will report outcomes of its discussion to the ECBS at its next meeting in October 2009 for further considerations and advice regarding the proposed course of action.  相似文献   

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