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Tetrodotoxin (TTX) is a potent neurotoxin responsible for many human intoxications and fatalities each year. The origin of TTX is unknown, but in the pufferfish, it seems to be produced by endosymbiotic bacteria that often seem to be passed down the food chain. The ingestion of contaminated pufferfish, considered the most delicious fish in Japan, is the usual route of toxicity. This neurotoxin, reported as a threat to human health in Asian countries, has spread to the Pacific and Mediterranean, due to the increase of temperature waters worldwide. TTX, for which there is no known antidote, inhibits sodium channel producing heart failure in many cases and consequently death. In Japan, a regulatory limit of 2 mg eq TTX/kg was established, although the restaurant preparation of "fugu" is strictly controlled by law and only chefs qualified are allowed to prepare the fish. Due to its paralysis effect, this neurotoxin could be used in the medical field as an analgesic to treat some cancer pains.

Studies on outbreaks or incidences of infectious diseases and food poisonings are the starting points in research. Analyses of the outbreaks will provide the mechanism by which the illnesses occur and the establishment of countermeasure. We report here some sensational outbreaks which recently occurred in Japan: 1) enterohemorrhagic Escherichia coli (EHEC) O157 outbreaks by pickled Chinese cabbage in Hokkaido, 2) EHEC O157/O111 outbreaks by raw beef in Toyama Prefecture, 3) parasitic food poisoning due to raw olive flounder consumption in the western Japan, and 4) botulism due to the consumption of vacuum packed food in Tottori Prefecture.

More than 27 outbreaks per year of food poisoning caused by consuming horse meat were reported in Kumamoto Prefecture (including Kumamoto City) from January 2009 to September 2011. It was found that the causative agent of the outbreaks was a protein with a molecular weight of 15 kDa that had originated from bradyzoites of Sarcocystis fayeri parasitizing the horse meat. Rabit ileal loop tests showed that pepsin treatment of homogenates of frozen horse meat containing the cysts of S. fayeri induced loss of toxicity, presumably by digestion of the proteinous causative agent(s). Slices of horse meat containing the cysts were frozen at below -20°C for various periods. The cysts were collected after thawing the slices, then treated in an artificial stomach juice containing pepsin. The bradyzoites of the cysts kept at -20°C for 48 hr or more completely disappeared. Simultaneously, the 15 kDa protein also disappeared in the frozen cysts. After notifying the public and recommending freezing treatment of horse meat, no subsequent cases of food poisoning were reported. This indicates that freezing of horse meat is effective to prevent the occurrence of food poisoning caused by consuming raw horse meat containing S. fayeri.

Food poisoning at care facilities for the elderly has been breaking out approximately ten cases per year nationwide from 2001 to 2010. Especially, it reflected the characteristics of food poisoning caused by noroviruses at a high rate. Usually we have been preventing from food poisoning by noroviruses working on existing measures such as temperature control of food materials, sanitary handlings of cooking tools and table wares, and so on. Additionally, the most effective measures to avoid secondary pollution at care facilities for the elderly is that all members at these facilities have to have a sense of crisis about food poisoning by noroviruses and managers at these facilities must take care of health control for all staff.

Appropriate handling and controlled temperature prevent cross-contamination and proliferation of contaminants in foods, thereby reducing the incidences of food-borne gastroenteritis in Japan. However, the incidence of Campylobacter jejuni/coli infection did not markedly decrease and has become one of the major causes of food-borne diseases. C. jejuni and C. coli are widespread in warm-blooded domestic animals; therefore, food products may easily become contaminated during processing. C. jejuni and C. coli do not proliferate in foods, nor resistant to freezing, drying and oxidative stresses, and the number is greatly reduced under such conditions. These properties should be considered for risk management of Campylobacter in food processing and manufacturing.

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.

We examined the acid resistance and verocytotoxin (VT) productivity of enterohemorrhagic Escherichia coli O157:H7 irradiated by microwave with a domestic microwave oven and a commercial microwave radiator equipped with a thermo-regulator. When the cell suspension (5 mL) chilled at 0 °C was treated with a domestic microwave oven at weak power (2.45 GHz, 100 W) for 60 s, the living cell number was reduced by 2 orders (final temperature, about 65 °C). The surviving cells showed lower acid resistance and VT productivity than nonirradiated cells. To examine the nonthermal effect of microwave on acid resistance and VT productivity, the cells in Luria-Bertani medium were intermittently irradiated to keep the culture temperature at 37 °C with the microwave radiator (2.45 GHz, 0.6 W/mL). The intermittent radiation slightly reduced the acid resistance, but clearly suppressed the VT productivity. Microwave oven is probably useful for reducing not only the living cell number but also the acid resistance and VT productivity of EHEC O157:H7., (© 2011 Institute of Food Technologists®)

Public health centers (PHCs, hokenjo in Japanese) are local government authorities responsible for public health in Japan. As of 2010, 494 centers were operating under the Ministry of Health, Labour and Welfare of Japan. While the general rule is that one PHC covers 300,000 inhabitants, several centers cover a population of more than 1 million. The roles of PHCs described in the Community Health Act include 1) propagation and improvement of information on community health, 2) vital statistics and other statistics on community health, 3) improvement of dietary conditions and food sanitation, 4) environmental sanitation including housing, water supply, sewage, waste disposal and public cleaning, 5) medical and pharmaceutical affairs, 6) matters involving public health nurses, 7) promotion and improvement of public medical services, 8) maternal, child, and elderly health, 9) dental health, 10) psychiatric health, 11) health of patients under long-term care due to incurable diseases, 12) prevention of infectious diseases, 13) laboratory tests on sanitation/environment, and 14) other functions needed to maintain/promote health in the community. Among those many roles, infectious disease controls are one of the most important. Concerning tuberculosis control, PHCs are responsible for the isolation of patients, health check-ups of those in close contact with infectious TB patients, and public subsidy of medical expenses for tuberculosis treatments. Food poisoning controls are also an important responsibility of PHCs, as are the conduct of surveys to trace suspicious foods and laboratory testing of samples from patients. To make these many measures effective, sufficient numbers of public health professionals are required.

When food safety is mentioned, people would think about food which is in compliance with Food Sanitation Act and standard, and edible food. Because there is difference in terms of food and additives standards between Japan and other countries, a variety of food cannot be imported from foreign countries to Japan. In addition, in 2006, with the introduction of the Positive List, which takes a close-up of pesticide remained in food and anti-biotic, we adopted an effective policy towards imported food which does not reach the national standards. On one hand, in order to ensure food safety, domestic producers, hotels, fast food stores, and restaurants all try to strengthen management on food quality and employees health. However, food poisoning happens frequently. Chemicals and natural poisoning play a part but the major part is played by micro-organism (bacteria). So it become more and more important to develop food safety policies to avoid harm from bad food. Therefore, as an authority with the responsibility of quarantine, inspection and registration, it is important to conduct food inspection and it is even more important to provide comprehensive suggestions.

According to Article 4 of the Food Safety Basic Law (Law No. 48 of 2003), food safety must be ensured by taking necessary measures appropriately at each step of the food supply process both in Japan and overseas. From this viewpoint, for ensuring safety of imported foods further, the quarantine stations have obligations such as confirmation of the import-notification documents submitted under Article 27 of the Law, issue of inspection orders in accordance with Article 26 of the Law for imported foods suspected with high probability of violating the Act (in order to prevent harm to public health from the perspective of food sanitation), and implement of monitoring inspection under Article 28 of the Law to enforce checking of the food-sanitation conditions of various imported foods. If a quarantine station or local organization (including prefectures, cities and specially designated wards that operate public health centers) identify any violation of the Law, the Ministry of Health, Labour and Welfare (hereinafter referred to as "the MHLW"), the quarantine station and the related prefecture shall cooperate to take appropriate measures to help the corresponded importer recall the food as soon as possible. In addition, taking measures to prevent recurrence of such violations by demonstration of examples of violations and guidance to importers. Under the recent situation of accidents such as addition of toxic substances to the food, it is important to make continuous efforts for achieving food safety in exporting countries. With recognition that assurance of the safety of the consumer from foodborn illness, it is necessary for the MHLW, the Agency of Consumer Affaires, local governments and related offices to make active efforts together through risk evaluation, risk management and the risk communication for 1 while measuring the communication.

A new transportation system is proposed recently to improve the defects of liquid transportation by tank trucks. This method is called "soft tank transportation system"; a driver installs a sac-like container (soft tank), which is made from a tarpaulin with high-pressure resistant-waterproof zippers, in a general cargo vehicle. To evaluate the quality of sterilized milk by using the soft tank transportation system, ground and marine transportation for a long distance which took about 36 h from the shipper's loading to the receiver's unloading in a high-temperature summer season (average outside temperature was 33.4 degrees C) were carried out. Although the difference of milk temperature before and after the delivery varied from -0.7 to +1.4 degrees C, there was no difference in milk quality (fat, nonfat solids, total dissolved solids, and pH) and no coliform bacteria were detected. It can be evaluated that sterilized milk was carried in keeping good conditions by soft tank transportation system.

Distrust of food safety has grown among the Japanese people after the occurrence of bovine spongiform encephalitis (BSE) in 2001. The Food Safety Commission was formed under the Cabinet Office and made a network among the ministries. The newly-established Consumer Agency may strengthen the quick response to emergencies. Shoku-iku (food and dietary education) Law is being implemented by the Cabinet Office with cooperation from relevant ministries and NGOs. Food Sanitation Law and Health Promotion Law are briefly explained, and the necessity of functional nutriology for non-nutrient biologically active substances is described. With regard to public health nutrition, a new food label showing energy balance and antioxidant unit (AOU) as a surrogate marker of fruit and vegetables has been developed for tailor-made nutrition which makes it easy to for individuals to control energy intake.

The nerve gas sarin has been responsible for tragic disasters in Matsumoto city, Nagano in 1994 and in the Tokyo subway system in 1995, which was a terrorist attack against non-military citizens. These chemical weapons exposures shocked the world, and have become sources of social concern. Thereafter there were several toxic substance-evoked incidents in Japan, specifically a poisoning due to curry containing arsenite at Wakayama city and foods and drinks containing other toxic chemicals. Following these tragic events, the Japanese government started to prepare a risk and medical management system for countering chemical and biological terrorism by developing a network of nationwide highly-sophisticated analytical instruments in police research institutes and emergency hospitals. Various ministries and National Research Institutes also provide information, guidelines and treatments for chemical and biological agents. In the event of an emergency such as a mass chemical exposure or mass food poisoning, information on "when, where, who, whom, what, how" should be reported rapidly and accurately to the first responding national organizations, such as police and fire departments, health care centers, and hospitals. Pharmaceutical scientists and pharmacists have been educated and trained on the handling of toxic chemical substances as well as drugs, and thus in the case of an event, they can become advisers for risk assessment and the analysis of drugs and chemicals. Japan has experienced food- and drink-poisonings as terrorism-like attacks. Poisonings caused by the herbicide paraquat and other pesticides including organophosphate insecticides, potassium cyanate and the above-mentioned arsenite-poisoned curry food have occurred. Because of easy access to internet-aided purchases of toxic substances and the import and export of foods, we must pay attention to possible massive exposures through foods and develop emergency management measures to counter them.

Objectives: To clarify the attitude of physicians toward the diagnosis and reporting on patients with foodborne disease after implementation of infectious disease prevention and medical treatment to patients as per the Infectious Diseases Act of 1999., Methods: A questionnaire, including experience of diagnosis and reporting on patients with foodborne disease, was mailed to all physicians in charge of AIDS treatment in medical facilities established as AIDS core hospitals., Results: Out of the 391 AIDS core hospitals, 224 (57%) cooperated with the survey. Seven hundred and four questionnaires were distributed to physicians and 681 (97%) were returned. The number of physicians with experience of diagnosing patients with foodborne disease was 391 (57%). One hundred and sixty-six physicians (57%) answered "Reported occasionally" and fifty-five (14%) answered "Never reported". The two main reasons for not reporting were "Did not report because I thought there were no other cases" and "Did not report because the case was not so severe"., Conclusions: A single or sporadic case must be reported by physicians to health authorities to ensure an early alert of illness or potential illness that could affect communities.

The average prevalence of reported foodborne illness from 1981 to 1995 was 2.44 per 100,000 population in Korea, and 28.01 in Japan. The mean case fatality rate in Korea was 0.74% and in Japan, 0.03%. When both prevalence and case fatality rates in Korea and Japan were compared during the same period, the prevalence in Japan was much higher than that in Korea. However, the case fatality rate of patients in Korea was much higher than that in Japan. The distribution of monthly and seasonal patterns of foodborne illness outbreaks strongly indicate the outbreaks may be associated with climatic conditions, frequencies of national holidays, and vacation seasons. Comparison study indicates that the foodborne illness outbreaks in Korea most frequently involved homemade foods (47% of the total cases); in Japan, restaurants accounted for 31.3%. Foodborne illness cases of bacterial origin in Korea were 59.3% of the total and included Salmonella spp. (20.7%). Vibrio (17.4%), Staphylococcus (9.7%), pathogenic Escherichia coli (2.4%), and other species (9.1%); in Japan, 72.8% of the total cases and the majority of the bacterial foodborne illness was caused by Vibrio (32.3%), Staphylococcus (15.9%), Salmonella (14.2%), pathogenic E. coli (3.0%), and other species (7.2%). In conclusion, the outbreaks of foodborne illness in Korea and Japan may be mainly caused by improper food handling, and their occurrences may be differentiated according to food sources.

We reviewed records of all outbreaks of food-borne illnesses due to schoollunch in Japan from 1987 through 1996 to determine the risk factors causing these outbreaks. Major hazards in 269 outbreaks were Salmonella spp., Campylobacter jejuni, Escherichia coli and Staphylococcus aureus. Foods including uncooked or partially cooked items, salad or egg products presented a high risk in 62 outbreaks with confirmed food sources. Contaminated food items were involved in 29 incidents (46.8%); storage of foods for an extended period before serving in 29 incidents (46.8%), inadequate cooking and cross contamination in 21 incidents (33.9%) each; infected employees in nine incidents (14.5%).

The mean MPN viable cell counts in 15 samples of sea water in which clams were held at the time of the onset of mass outbreaks of food poisoning, the number of food poisoning outbreaks, and prevalence of Kanagawa phenomenon-positive strains, and effectiveness of measures to control food poisoning were investigated over 6 years from 1990 to 1995. The results obtained were as follows: 1. Of 6 materials, including sea water and shellfish, which were examined to determine the best marker material for prediction of Vibrio parahaemolyticus food poisoning, sea water in which clams were held was found to be the most appropriate. 2. Except for the outbreaks in 1994, all Vibrio parahaemolyticus food poisoning occurred after the mean MPN viable cell count in 15 samples of sea water in which clams are kept reached 10(5) cells/100 ml. 3. The number of outbreaks of Vibrio parahaemolyticus food poisoning could be predicted based on the time at which the mean MPN viable cell count reached 10(5) cells/100 ml. 4. In 1995, sea water in which clams were held was cultured and examined for thermostable direct hemolysin gene by PCR method. Thermostable direct hemolysin gene was detected in 3 of 82 samples. Thirty-nine Kanagawa phenomenon-positive strains were isolated from 2 of these 3 samples. 5. Kanagawa phenomenon-positive strains were detected after the mean MPN viable cell count in 15 samples of sea water in which clams were kept reached 10(5) cells/100 ml. 6. Four serotypes of Kanagawa phenomenon-positive strains were detected, and they were involved in 5 (45%) of the 11 cases of Vibrio parahaemolyticus food poisoning that occurred in the same year. These serotypes were observed also in 28 (38%) of the 74 strains isolated from food poisoning patients. 7. No conclusion could be made concerning the effectiveness of measures to control food poisoning.