[Trends of food poisonings caused by natural toxins in Japan, 1989-2011].

In order to reduce the health risk associated with food poisonings caused by natural toxins, it is necessary to implement risk management strategies based on previous poisoning data and risk factors. In present study, we statistically analyzed natural toxin food poisoning (NTFP) data published by the Ministry of Health, Labour and Welfare from 1989 to 2010 in Japan and reviewed the trends of NTFP for each natural toxin hazard. Since 1989, the number of incidents of NTFP in each year has not been reduced. Prevention and control are needed to reduce the risk of NTFP. The major site for all hazards was "at home". This result suggested that consumer education is critically important to inform about NTFP occurrence, preventive measures and emergency treatments. Furthermore, countermeasures for NTFPs which have never occurred in the past in Japan should be considered, because of the increasing variety of imported foods and changes resulting from the inerease of sea temperature with global warming.

Effect of reducing the top concentration used in the in vitro chromosomal aberration test in CHL cells on the evaluation of industrial chemical genotoxicity.

A current concern with in vitro mammalian cell genotoxicity testing is the high frequency of false or misleading positive results caused in part by the past use of excessively high test concentrations. A dataset of 249 industrial chemicals used in Japan and tested for genotoxicity was analyzed. Of these, 116 (46.6%) were positive in the in vitro chromosomal aberration (CA) test, including 6 that were positive only at test concentrations >10mM. There were 59 CA-positive chemicals at test concentrations ≤ 1mM. At >1mM, 51 chemicals were CA-positive, including 13 Ames-positive chemicals, which were therefore not "missed" by the test battery. Thus, 38 potentially positive chemicals would not have been detected in the test battery if the top test concentration was limited to 1mM in CA test. Analysis of the relevance of CA results on the 38 missed chemicals was conducted based on a weight of evidence approach, including evaluations of effects of extreme culture conditions (low pH, high toxicity, or precipitation), in silico structural alert analysis, in vivo genotoxicity and carcinogenicity test data (where available), mode of action, or information from closely related chemicals. After an exhaustive review, there were four chemicals with some concern for human health risk assessment, nine with minimal concern, and the remaining 25 with negligible concern. We apply different top concentrations to the 38 missed chemicals to identify the most accurate approach for predicting the genotoxicity of industrial chemicals. Of these 2mM or 1mg/mL, whichever is higher, was the most effective in detecting these chemicals, i.e., relatively higher (8/13) or lower (17/25) detection among 13 chemicals with some or minimal concern, or 25 with negligible concern, respectively. Lower top concentration limits, 1mM or 0.5mg/mL, whichever is higher, are not as effective (2/13) for detecting these chemicals with concern. Therefore, we conclude 2mM or 1mg/mL, whichever is higher, would be an appropriate top concentration limit for testing industrial chemicals for chromosome damage.

Estimating the burden of acute gastroenteritis and foodborne illness caused by Campylobacter, Salmonella, and Vibrio parahaemolyticus by using population-based telephone survey data, Miyagi Prefecture, Japan, 2005 to 2006.

Most cases of acute gastroenteritis and foodborne disease are not ascertained by public health surveillance because the ill person does not always seek medical care and submit a stool sample for testing, and the laboratory does not always test for or identify the causative organism. We estimated the total burden of acute gastroenteritis in Miyagi Prefecture, Japan, using data from two 2-week cross-sectional, population-based telephone surveys conducted in 2006 and 2007. To estimate the number of acute gastroenteritis illnesses caused by Campylobacter, Salmonella, and Vibrio parahaemolyticus in Miyagi Prefecture, we determined the number of cases for each pathogen from active laboratory-based surveillance during 2005 to 2006 and adjusted for seeking of medical care and submission of stool specimens by using data from the population-based telephone surveys. Monte Carlo simulation was used to incorporate uncertainty. The prevalence of acute gastroenteritis in the preceding 4 weeks was 3.3% (70 of 2,126) and 3.5% (74 of 2,121) in the winter and summer months, yielding an estimated 44,200 episodes of acute gastroenteritis each year in this region. Among people with acute gastroenteritis, the physician consultation rate was 32.0%, and 10.9% of persons who sought care submitted a stool sample. The estimated numbers of Campylobacter-, Salmonella-, and V. parahaemolyticus -associated episodes of acute gastroenteritis were 1,512, 209, and 100 per 100,000 population per year, respectively, in this region. These estimates are significantly higher than the number of reported cases in surveillance in this region. Cases ascertained from active surveillance were also underrepresented in the present passive surveillance, suggesting that complementary surveillance systems, such as laboratory-based active surveillance in sentinel sites, are needed to monitor food safety in Japan.

Expert review for GHS classification of chemicals on health effects.

Intoxication as a result of chemical accidents is a major issue in industrial health. The Globally Harmonized System of Classification and Labelling of Chemicals (GHS) provides a framework for hazard communication on chemicals using labelling or safety data sheets. The GHS will be expected to reduce the number of chemical accidents by communicating the hazards posed and prompting safety measures to be taken. One of the issues which may be a barrier to effective implementation of the GHS results from discrepancies in GHS classifications of chemicals across countries/regions. The main reasons are the differences in information sources used and in the expertise of people making the classification (Classifiers). The GHS requests expert judgment in a weight of evidence (WOE) approach in the application of the criteria of classification. A WOE approach is an assessment method that considers all available information bearing on the determination of toxicity. The quality and consistency of the data, study design, mechanism or mode of action, dose-effect relationships and biological relevance should be taken into account. Therefore, expert review should be necessary to classify chemicals accurately. However, the GHS does not provide any information on the required level of expertise of the Classifiers, definition of who qualifies as an expert, evaluation methods of WOE or data quality, and the timing of expert judgment and the need for updating/re-classification as new information becomes available. In this paper, key methods and issues in expert reviews are discussed. Examples of expert reviews and recommendations for harmonized classification are also presented.

Echocardiography for the detection of valvulopathy associated with the use of ergot-derived dopamine agonists in patients with Parkinson's disease.

OBJECTIVE: The ergot-derived dopamine agonists, cabergoline and pergolide, are associated with valvulopathy risk. In Japan, product labels were revised in April 2007 to recommend periodic echocardiography for patients taking these dopamine agonists, however, the compliance of physicians to follow through with this recommendation is unknown. This study assessed changes in echocardiography evaluation of patients with Parkinson's disease (PD) taking cabergoline or pergolide before and after the label revision and examined the factors related with echocardiography performance. METHODS AND PATIENTS: Medical claim data from January 2005 to December 2008 were used. Patients were divided into a C-P group (prescribed either cabergoline or pergolide) or reference group (prescribed other anti-PD drugs), and further classified based on whether they were prescribed these drugs "pre-revision" or "post-revision." The Cochran-Armitage trend test was used to compare the proportion of echocardiograms obtained amongst these groups before and after the revision. The frequencies of echocardiograms performed among the treatment groups for each period were compared by Fisher's exact test. RESULTS: A total of 222 subjects (C-P, 73; reference, 149) were assessed. The proportion of C-P patients undergoing echocardiography increased from 4.8% to 27.9% after revision of product labels (p=0.001), which was higher than those in the reference group following label revisions (11.0%) (p=0.014). Prescription duration of C-P after the revision was longer in the patients with echocardiography than without echocardiography (p=0.026). CONCLUSION: Although echocardiography evaluations increased, more than 70% of PD patients prescribed cabergoline or pergolide did not undergo such assessment despite the product label recommendation. Adherence to drug safety recommendations should be facilitated with more feasible and effective measures.

[Analysis of drug safety information using large-scale adverse drug reactions database].

The worldwide situations of drug safety have changed dramatically. Drugs are used based on the evaluation of safety data collected in clinical practice worldwide. US Food Drug Administration collects spontaneous reports and requires manufacturers to report adverse drug reactions (ADRs) of US marketed drugs occurring worldwide. These worldwide data are available through the Adverse Event Reporting System (AERS) (about 4.1 million reports on about 3,073,340 patients, for 13 years: 1997.4th qr-2010.4th qr.). The current issues are how to analyze and utilize such large-scale safety data. Potential biases should always be kept in mind, because AERS is based on spontaneous reports. However, its huge volumes and exhaustiveness allow for sufficient scientific evaluation with the aid of current IT technology. Therefore, analysis of large-scale ADR database becomes a new research area not only from the medical science but also from the statistical viewpoint. In this report, I introduce some case studies in which we analyzed the AERS data on psychotropics including antipsychotics, antiepileptics, and antidepressants. Antipsychotics caused ADRs specific to each drug, and, in combination therapy, increased the incidences of diabetes mellitus, pancreatitis, and neuroleptic malignant syndrome; antiepileptics caused AEs (adverse events) including serious skin reactions such as Stevens-Johnson syndrome (SJS), congenital anomaly, and closed-angle glaucoma; and antidepressants caused AEs including serotonin syndrome, suicidal events, and congenital anomaly, and AEs occurring at a higher incidence for other indications, drugs often used in the elderly and AEs in combination therapy. We have analyzed ADRs associated with concomitant drug therapies using Bayesian approach. In the analysis we faced difficulties of overdispersion and we have to estimate a number of parameters, given a large number of target drugs as well as ADRs. In addition, ADR reports are not collected from uniform populations, we also have to consider the variations in the target populations. So, we use Bayesian statistics. Bayesian analysis has become feasible with advances in computer technologies and the Markov chain Monte Carlo (MCMC) methods. It allows us to analyze ADRs associated with concomitant drug therapies and estimate the ADR signals for each drug. Therefore, the analysis and evaluation of large-scale ADR database can provide important safety information in clinical practice and the studies on ADR database are the most important issues in ensuring the postmark safety of pharmaceutical products.

Establishment of a transgenic hairy root system in wild and domesticated watermelon (Citrullus lanatus) for studying root vigor under drought.

Root vigor is an important trait for the growth of terrestrial plants, especially in water-deficit environments. Although deserts plants are known for their highly developed root architecture, the molecular mechanism responsible for this trait has not been determined. Here we established an efficient protocol for the genetic manipulation of two varieties of watermelon plants: a desert-grown wild watermelon that shows vigorous root growth under drought, and a domesticated cultivar showing retardation of root growth under drought stress. Agrobacterium rhizogenes-mediated transgenic hairy roots were efficiently induced and selected from the hypocotyls of these plants. Transgenic GUS expression was detected in the roots by RT-PCR and histochemical GUS staining. Moreover, a liquid culture system for evaluating their root growth was also established. Interestingly, growth of the hairy roots derived from domesticated variety of watermelon strongly inhibited under high osmotic condition, whereas the hairy roots derived from wild variety of watermelon retained substantial growth rates under the stress condition. The new protocol presented here offers a powerful tool for the comparative study of the molecular mechanism underlying drought-induced root growth in desert plants.

Practical issues on the application of the GHS classification criteria for germ cell mutagens.

The Globally Harmonized System of Classification and Labeling of Chemicals (GHS) requires classification of chemicals on germ cell mutagenicity. The Japanese government has conducted GHS classification on about 1400 chemicals in a 2-year project (J-GHS) for implementing GHS domestically. Prior to the classification work, the technical guidance for classification of germ cell mutagens was prepared. This guidance introduces the concept of heritable mutagenicity, and presents detailed criteria for germ cell mutagens, test data to be used, and a practical decision tree for classification. These practical guidance and supporting explanations are useful for non-expert Classifiers (scientists applying the classification criteria). Several issues, however, were identified during the course of J-GHS and in re-evaluating the classification results. These include: (1) the information sources when available data are limited; (2) lack of understanding GHS classification criteria or insufficient review of the information by Classifiers; (3) varying opinions of experts on data quality and weight of evidence, and; (4) decision tree approaches, e.g., inadequacy for use in overall evaluation in some cases. Ideally, classification should be performed by Classifiers with high expertise using high quality information sources. Genetic toxicologists as experts should consider data quality and reliability, and give a critical review of all available information for support of classification. A weight of evidence approach is also required to assess mutagenic potential of chemicals. Critical points for suitable classification for GHS are discussed.

[Histamine food poisonings in Japan and other countries].

Histamine food poisonings are allergy-like food poisonings caused by the ingestion of spoiled fish containing markedly elevated histamine levels. We examined histamine food poisonings in Japan from 1998 to 2008. In average 8 food poisonings and 150 cases were reported annually and there was no fatality case. In more than 80% of remaining food samples, histamine content exceeded 20 mg/100 g. These poisonings were caused by tuna, billfish (marlin) and mackerel, which contained higher level of histamine than other fishes in histamine food poisonings in Japan. Cooking methods of these fishes were mainly "broiled". We also studied histamine food poisonings in other countries. Tuna was the main fish in histamine food poisonings reported to Centers for the Disease Control and Prevention (CDC) in the US and Ozfoodnet in Australia from 2000 to 2006. In the US, histamine food poisonings were also caused by mahimahi and escolar fish. Our review will be useful for in taking measures to reduce risk of histamine food poisonings.

[Studies on the results of monitoring of veterinary drug residues in food products of animal origin in Japan and other countries].

The positive list system was introduced in Japan for agricultural chemicals such as pesticides, feed additives and veterinary drugs in May 2006. After this time, food containing residues of these chemicals exceeding MRLs, or the default tolerance (uniform limit: 0.01 ppm) cannot be marketed in Japan. The number of chemicals to be tested for imported food at the port increased remarkably. We studied on the results of monitoring of imported food for the residues of veterinary drugs and change in trend of violation after the enforcement of the system. The number of violation of the veterinary drugs in imported food increased largely, most of them were attributed to chloramphenicol and nitrofurans in seafood from Asian countries. Monitoring of the veterinary drugs in seafood in other countries such as EU, United States, United Kingdom and Australia were also studied.

The human health burden of foodborne infections caused by Campylobacter, Salmonella, and Vibrio parahaemolyticus in Miyagi Prefecture, Japan.

To estimate the human health burden of foodborne infections caused by Campylobacter, Salmonella, and Vibrio parahaemolyticus in Japan, an epidemiological study was conducted in Miyagi Prefecture. Laboratory-confirmed infections among patients with diarrhea caused by the three pathogens were ascertained from two clinical laboratories in the prefecture from April 2005 to March 2006. To estimate the number of ill persons who were not laboratory-confirmed, we estimated physician-consultation rates for patients with acute diarrhea by analyzing foodborne outbreak investigation data for each pathogen and the frequency at which stool specimens were submitted from a physician survey. Each factor was added to a Monte-Carlo simulation model as a probability distribution, and the number of laboratory-confirmed cases was extrapolated to estimate the total number of ill persons. The estimated incidence of foodborne infections per 100,000 per year in this region estimated by this model was 237 cases for Campylobacter, 32 cases for Salmonella, and 15 cases for V. parahaemolyticus. Simulated results indicate a significant difference between our estimated incidence and the reported cases of food poisoning in this region. An enhanced surveillance system is needed to complement the present passive surveillance on foodborne illnesses in Japan to identify food safety issues more precisely, and to monitor the effectiveness of risk management options.

Monitoring minimization of grade B environments based on risk assessment using three-dimensional airflow measurements and computer simulation.

A practical, risk-based monitoring approach using the combined data collected from actual experiments and computer simulations was developed for the qualification of an EU GMP Annex 1 Grade B, ISO Class 7 area. This approach can locate and minimize the representative number of sampling points used for microbial contamination risk assessment. We conducted a case study on an aseptic clean room, newly constructed and specifically designed for the use of a restricted access barrier system (RABS). Hotspots were located using three-dimensional airflow analysis based on a previously published empirical measurement method, the three-dimensional airflow analysis. Local mean age of air (LMAA) values were calculated based on computer simulations. Comparable results were found using actual measurements and simulations, demonstrating the potential usefulness of such tools in estimating contamination risks based on the airflow characteristics of a clean room. Intensive microbial monitoring and particle monitoring at the Grade B environmental qualification stage, as well as three-dimensional airflow analysis, were also conducted to reveal contamination hotspots. We found representative hotspots were located at perforated panels covering the air exhausts where the major piston airflows collect in the Grade B room, as well as at any locations within the room that were identified as having stagnant air. However, we also found that the floor surface air around the exit airway of the RABS EU GMP Annex 1 Grade A, ISO Class 5 area was always remarkably clean, possibly due to the immediate sweep of the piston airflow, which prevents dispersed human microbes from falling in a Stokes-type manner on settling plates placed on the floor around the Grade A exit airway. In addition, this airflow is expected to be clean with a significantly low LMAA. Based on these observed results, we propose a simplified daily monitoring program to monitor microbial contamination in Grade B environments. To locate hotspots we propose using a combination of computer simulation, actual airflow measurements, and intensive environmental monitoring at the qualification stage. Thereafter, instead of particle or microbial air monitoring, we recommend the use of microbial surface monitoring at the main air exhaust. These measures would be sufficient to assure the efficiency of the monitoring program, as well as to minimize the number of surface sampling points used in environments surrounding a RABS.

[Study on pesticides residue monitoring data in some countries of the world].

In May 2006, the positive list system for residues of pesticide and veterinary medicines in food was introduced in Japan. Under this system, the number of regulated pesticides remarkably increased. The information of food items and foods/origins combinations in which pesticides were frequently detected over the detection limits and/or exceeding MRL in the foreign pesticides residue monitoring are useful to achieve the Japanese pesticides residue monitoring programme more efficiently and effectively. We investigated pesticides residue monitoring data published by food safety authorities of North America, Europe and Oceania countries in their web sites. We focused food items and foods/origins combinations which Japan imported in large quantity. Most of pesticides residues detected in twelve food items were mainly fungicides and insecticides, and some residues level of their samples were exceeding the MRLs (maximum residue limits) established in Japan. Most of pesticides residues detected in European countries were also fungicides (e.g. maneb-group and procymidone) and insecticides (e.g. pirimiphos-methyl and malathion), but herbicides were less detected. We provided the collection of Web links to information sites of MRLs and the pesticides residue monitoring reports published by food safety authorities of other countries.

[Study on usage of pesticides in various countries].

Usage of pesticides in food items in export countries was studied, focusing items which Japan imports in large quantity. Japan has imported field crops such as wheat, corn and soy bean, and also grapefruit in large quantity on a weight base, mainly from United States, Australia and Canada. While, Japan has imported various kinds of vegetables in which China had the largest share. We collected usage data of pesticides for 44 food items of 17 countries of 2004. Pesticides which were used frequently (usage rank within top ten in each item/country) were dichlorvos, carbofuran, chlorpyrifos, dimethoate (insecticides), mancozeb, carbendazim, thiophanate-methyl, chlorthalonil (fungicides), glyphosate, 2,4-D, paraquat, acetochlor (herbicides). Carbendazim, thiophanate-methyl, acetochlor and dichlorvos were mainly used in China. Dithiocarbamates are used frequently in various food items in various countries, and also frequently detected in monitoring in foreign countries. Some pesticides such as bisultap, monosultap, etaboxam and triazmate were used only in certain countries, and available information on toxicity or analytical method was very limited. Some of pesticides described above have not been analyzed in the pesticide residue monitoring in Japan before 2005,however, many of them are subjects of analysis for import food after 2006 with the enforcement of positivelist system for residues of pesticide and veterinary medicines in food in Japan.

[Chemical incidents and gathering information on toxicity].

Major cases of chemical incidents and information on chemical agents and chemical terrorist attacks are outlined. Since the late 1990s, major incidents occurred consecutively, such as two cases of sarin attack in 1994 and 1995, an oil spill from a Russian oil tanker in the Japan Sea in 1997, arsenic poisoning in Wakayama in 1998, the criticality incident at Tokai-Mura in 1999 in Japan, and terrorist attacks on September 11, 2001, in New York. The importance of crisis management and cooperation among relevant organizations has been emphasized. To provide information for an appropriate and quick response in emergencies, we prepared a Web portal site for information on chemicals including chemical agents, a chemical incident database, and links to relevant Web sites. In intentional cases of poisoning caused by toxic chemicals in Japan, 111 cases were collected mainly from a newspaper database (1984-1999). Many copy-cat poisonings occurred, especially in 1984-1985 and in 1998 just after an arsenic poisoning incident in Wakayama. Many cases occurred in the laboratories of institutes, universities, and hospitals where various types of chemicals are used.

[Trends in the utilization of internet for facilitating transparent and more active stakeholder participation in the Codex process in several countries].

Codex standards have become the benchmarks against which national food safety control measures and regulations are evaluated within the legal parameters of the World Trade Organization (WTO) Agreements. For this reason, high-level representation at meetings of the Codex Alimentarius Commission, it's related committees and ad hoc intergovernmental task forces continue to be a priority for many governments. Opportunities broaden for stakeholder input towards the development of government positions for all Codex work through the national Codex website. Some countries utilize a national Codex website as an effective communication tool between the national Codex Contact Point (CCP) and stakeholders. In this regard, stockholder participation in the national Codex preparation process is insufficient in Japan. One of the reasons for this could be the lack of information on Codex and the insufficient understanding of the work of Codex among Japanese stakeholders. To overcome these problems, more active and effective utilization of the Japanese Codex webpage should be considered. In this paper, we show analyses of recent trends of the information on Codex available from national Codex websites from six countries in order to identify the needs to establish a similar Japanese Codex website and possible contents of the site. The six websites of the national CCPs analyzed are regularly updated and utilized for the means of active information interchange between national CCPs and stakeholders, for example, providing basic general information on Codex, including its purpose, structure and meeting schedule, posting Codex working documents open for comment, and the Terms of Reference, key issues under discussion, and delegation reports of the previous sessions. Consequently, stakeholders interested in the paper could submit their comments to the delegate of the country whose contact details are made available on the website. This is one of the examples of active stakeholder participation. By establishing a similar communication system in Japan between the National Codex Contact Point and stakeholders, a more active stakeholder participation in the national codex process could be achieved. The web site could be used to provide information on the issues under discussion in each Committee and summaries of the Codex working documents circulated for the comments and their potential implications in Japan.

[Development of the databases for ADI (acceptable daily intake) and relevant information on food additives, pesticides and veterinary drugs].

Databases for ADI (Acceptable Daily Intake) and relevant information on food additives, pesticides and veterinary drugs were developed. The databases we developed are easily accessible on the web, and contain ADIs, latest evaluation year, classification and use, as well as synonym and CAS registry number. The databases are designed to be easily updated by researchers as ADI and relevant information are updated or added without delay. The database for food additives has already provided from the homepage of NIHS, and the access log of the web site was 1325/month in December 2005 and 2179/month in March 2006.

[Outbreaks of Salmonella in infants associated with powdered infant formula].

Historically, outbreaks associated with Salmonella-contaminated milk products were recognized as early as the 1950's in the United Kingdom and Bulgaria. In the 1960's and 1970's there were also a number of outbreaks related to Salmonella in various powdered milk products. As a result, Salmonella criterion was included in the Codex Code of hygienic practice for foods for infants and children. Between 1985 and 2005 at least 6 outbreaks of salmonellosis, involving as many as 250 infants, have been associated with powdered infant formula (PIF). In 2005, in France, an outbreak affecting more than 100 infants was associated with PIF contaminated with Salmonella Agona. These reported outbreaks indicated that problems persisted. Experts from two FAO/WHO Expert Consultations, held in 2004 and 2006, concluded that intrinsic contamination of PIF with Enterobacter sakazakii and Salmonella has been a cause of infection and illness in infants, including severe disease which can lead to serious developmental sequelae and death. Most of the Salmonella outbreaks associated with PIF involved unusual Salmonella serotypes, which likely aided in the recognition of these outbreaks. In many regions of the world where Salmonella serotyping is not routinely performed, identification of geographically or temporarily diffused outbreaks could be difficult. It is therefore important to use the appropriate methodology to detect unusual strains of Salmonella that cause illnesses in infants, such as the lactose-positive strain, and to perform serotyping and/or pulsed-field gel electrophoresis (PFGE) genotyping for rapid identification of Salmonella outbreaks and to establish linkages between the illness and implicated food.