Food safety (Tokyo, Japan)最新文献

Hexavalent chromium (Cr(VI)) is toxic, carcinogenic, and mutagenic substances. Oral exposure to Cr(VI) is thought to be primarily from drinking water. However, under the certain reporting limit (~0.1 µg/L), percentage of Cr(VI) concentration in mineral water products under the reporting limit were estimated higher than 50%. Data whose values are below certain limits and thus cannot be accurately determined are known as left-censored. The high censored percentage leads to estimation of Cr(VI) exposure uncertain. It is well known that conventional substitution method often used in food analytical science cause severe bias. To estimate appropriate summary statistics on Cr(VI) concentration in mineral water products, parameter estimation using the Markov chain Monte Carlo (MCMC) method under assumption of a lognormal distribution was performed. Stan, a probabilistic programming language, was used for MCMC. We evaluated the accuracy, coverage probability, and reliability of estimates with MCMC by comparison with other estimation methods (discard nondetects, substituting half of reporting limit, Kaplan-Meier, regression on order statistics, and maximum likelihood estimation) using 1000 randomly generated data subsets (n = 150) with the obtained parameters. The evaluation shows that MCMC is the best estimation method in this context with greater accuracy, coverage probability, and reliability over a censored percentage of 10-90%. The mean concentration, which was estimated with MCMC, was 0.289×10^-3 mg/L and this value was sufficiently lower than the regulated value of 0.05 mg/L stipulated by the Food Sanitation Act.

Food Safety Commission of Japan (FSCJ) was requested by the Ministry of Health, Labour and Welfare (MHLW) to conduct a risk assessment of deoxynivalenol (DON) to assure the maximal level for DON in foods. Previously, FSCJ had conducted a self-tasking risk assessment of DON and nivalenol (NIV) in 2010. In the current 2nd edition, only the assessment of DON has been revised. Grains contaminated with DON may be also contaminated with its derivatives, namely, 3-acetyldeoxynivalenol (3-Ac-DON), 15-acetyldeoxynivalenol (15-Ac-DON) and deoxynivalenol-3-glucoside (DON-3-glucoside). However, these substances orally ingested are rapidly biotransformed into DON. Therefore, FSCJ identified the total DON (sum of DON and its derivatives) to be assessed. The toxicity of DON was assessed based on the data of absorption-distribution-metabolism-excretion (ADME), acute toxicity, sub-acute toxicity, chronic toxicity, carcinogenicity, reproductive/developmental toxicity, genotoxicity, and immunotoxicity. DON was considered to have no significant genotoxic activity in vivo. The no-observed-adverse-effect level (NOAEL), based on the two-year chronic toxicity study in mice, was set at 0.1 mg DON/kg bw/day. By applying an uncertainty factor (UF) of 100, the TDI for DON was determined as 1 µg /kg bw/day. The average estimated exposure levels of total DON were 0.09 µg /kg bw/day and 0.22 µg/kg bw/day in the whole population and the 1-6 years group, respectively, by the Monte-Carlo method. The average exposure level in Japan was thus judged to be below the TDI, although a chance to exceed the TDI remains possible in the 1-6 years group depending on eating habits and DON contamination. For NIV, the genotoxic property was not able to be assessed due to the limited availability of the experimental data. No carcinogenic effect was observed in a two-year chronic toxicity study in mice, and the International Agency for Research on Cancer (IARC) also classifies Fusarium spp toxins including NIV to be in group 3. FSCJ thus judged that TDI can be set for NIV. Based on various toxicity studies, the TDI of NIV was determined at 0.4 µg/kg bw/day by taking into account of LOAEL 0.4 mg NIV/kg bw/day in a subacute toxicity study in rats with 90-day oral administration and UF of 1,000. The exposure level of NIV in Japan was estimated to be below the TDI. FSCJ judged it's unlikely that NIV intake leads to adverse health effects in general population.

To afford the future agenda of risk communication through an evaluation of the past, we examined the changes in risk perception in the food safety sector over the 15 years (2004-2018) since the establishment of the Food Safety Commission of Japan (FSCJ) in 2003 by analyzing the data of the food safety monitor survey. Hazards such as contaminants including cadmium, methylmercury and arsenic, and pesticide residues caused high levels of concern among the public in 2004. In contrast, hazards such as food poisoning by harmful microorganisms and so-called "Health foods" have been ranked high among concerns since 2008 and 2014, respectively. Scoring of concern levels showed that concern related to food additives and pesticide residues intentionally added to foods and controlled has gradually decreased in a time-dependent manner. These concern scores were considerably lower in male monitors than in female ones; the scores were also lower for individuals with professional experience in the food sector than without the experience. The concern scores for contaminants were lower for males with professional experience. The concern scores related to food poisoning and health foods were not decreased and were remained high in recent years. These scores did not show clear dependence on job experience or gender of the monitors. A gap between food specialists and other attributes in the basic recognition of risk seems to make it difficult to communicate effectively and constructively among various interested individuals. To improve the quality of risk communication in the food safety field, it will be necessary to provide scientific knowledge and information regarding food safety management mechanisms for individuals without professional experience in the food sector, taking into account the changes in information media and influence on risk perception.

This study used questionnaires to evaluate knowledge levels of risk management of raw-consumption of oysters and of norovirus as health hazards among monitors signed up for Food Safety Commission of Japan (FSCJ) having work experiences in food fields. The mean scores of monitors on norovirus knowledge were relatively high (79%), but on oyster raw-consumption were low (64%). Scores varied depending on occupational experiences; highest among administrative officials, high among researchers in food companies, and low among medical workers and educators. The higher scores with more practical experiences for risk management of oyster raw-consumption and norovirus were observed among the monitors. These monitors were expected better to recognize the risks, wheres only few monitors among the opinion-leaders replied correctly to all the questions. These results suggest the need of improvement on the management system for oyster raw-consumption, from the current complicated to the more precise and reinforced for consumers. To efficiently manage the risk associated with the consumption of raw oysters, the government should provide more relevant information of risk management to persons having interest, particularly influencers, in order to disseminate information and to improve knowledge among cooks and consumers.

Food Safety Commission of Japan (FSCJ) was requested by the Ministry of Health, Labour and Welfare (MHLW) to conduct a risk assessment of cattle meat and offal imported from the United States of America (U.S.A.), Canada and Ireland. FSCJ assessed potential influences on bovine spongiform encephalopathy (BSE) risks to human health in cases of the alteration of cattle age to be allowed to import of cattle meat and offal from the three countries, from the current under 30 months of age to no age limitation, in line with the international standards for mitigating BSE risks. FSCJ judges that the control measures regarding "risks related to slaughtering and meat processing" are appropriately implemented in the three countries. FSCJ concludes that potential variations of BSE risks to human health by removing the age limit on cattle meat and offal excluding specified risk material (SRMs) imported from the three countries in line with the international standards is negligible.

Elution of cesium-137 (¹³⁷Cs) from tofu into water was investigated to know the behavior of ¹³⁷Cs during preservation and cooking. The food processing retention factor (Fr) reached 0.55 when tofu was soaked in water at a ratio of 1:2 w/w for 24 h at 4°C. Doubling the amount of water did not further significantly decrease Fr. When tofu was held in water at a ration of 1:2 w/w at a temperature of 80℃ for 50 min, Fr was 0.72. Increasing the amount of water to 10 times the tofu weight did not further reduce Fr significantly. Cesium-137 is mostly bound to tofu and does not freely diffuse into water. Tofu was then soaked in water at a ratio of 1:2 w/w at 4℃ for 24 h, placed in new water at a ratio of 1:2 w/w, and held at 80℃ for 50 min, resulting in an Fr 0.33. This value is close to an estimated Fr calculated by multiplying the Fr of 0.55 from soaking at 4°C by the Fr of 0.72 from the hot water treatment. The calculated Fr from soybeans sequentially processing into tofu, soaking tofu at 4°C for 24 h and in hot water at 80°C for 50 min was about 0.1, indicating 90% removal of ¹³⁷Cs. Degree of decrease in ¹³⁷Cs during preservation and cooking of tofu demonstrated in this study will be useful for exposure assessment of ¹³⁷Cs through oral intake of contaminated soybeans after processing and cooking.

Human CYP3A4 is involved in metabolisms of diverse hydrophobic chemicals. Using the data of therapeutic azole fungicides known to interact with CYP3A4, applicability of CYP3A4 Template system was first confirmed to reconstitute faithfully the interaction on Template. More than twenty numbers of pesticide azoles were then applied to the Template system. All the azole stereo-isomers applied, except for talarozole, interacted through nitrogen atoms of triazole or imidazole parts and sat stably for inhibitions through fulfilling three-essential interactions. For their CYP3A4-mediated oxidations, clear distinctions were suggested among the enantiomers and diastereomers of azole pesticides on Templates. Thus, the stereoisomers would have their-own regio- and stereo-selective profiles of the metabolisms. A combined metabolic profile of each azole obtained with CYP3A4 Template system, however, resembled with the reported profile of the in vivo metabolism in rats. These results suggest the major roles of CYP3A forms on the metabolisms of most of azole pesticides in both rats and humans. Free triazole is a metabolite of azole fungicides having a methylene-spacer between triazole and the rest of the main structures in experimental animals and humans. During the simulation experiments, a placement for the oxidation of a methylene spacer between the triazole and main carbon-skeleton was found to be available throughout the azole fungicides tested on Template. The occurrence of this reaction to lead to triazole-release is thus discussed in relation to the possible involvement of CYP3A forms.

Colistin is a critically important antibiotic for humans. The Japanese government withdrew colistin growth promoter and shifted therapeutic colistin to a second-choice drug for pigs in 2017. A quantitative release assessment of mcr-mediated colistin-resistant Escherichia coli (E. coli) in Japanese finisher pigs was conducted under the World Organisation for Animal Health (OIE) risk assessment framework. Input data included colistin resistance and mcr-1-5 test results for E. coli isolates in the Japan Veterinary Resistance Monitoring System (JVARM), postal survey results regarding indication disease occurrence and colistin use by swine veterinarians in 2017 and 2018, and colistin resistance and mcr monitoring experiments at four pig farms in 2017-2018. An individual-based model was developed to assess the risk: the proportion of Japanese finisher pigs with mcr-1-5-mediated colistin-resistant E. coli dominant in the gut on an arbitrary day. Before implementing risk management measures, the risk was estimated to be 5.5% (95% CI: 4.2%-10.1%). At 12 months after stopping colistin growth promoter, the proportion of pigs with plasmid-mediated colistin-resistant E. coli declined by 52.5% on the experiment farms (95% CI: 8.7%-80.8%). The probability of therapeutic colistin use at the occurrence of bacterial diarrhea declined from 37.3% (95% CI: 30.3%-42.5%) in 2017 to 31.4% (95% CI: 26.1%-36.9%), and that of edema disease declined from 55.0% (95% CI: 46.0%-63.7%) to 44.4% (95% CI: 36.9%-52.0%). After risk management implementation, the risk was estimated to have declined to 2.3% (95% CI: 1.8%-4.3%; 58.2% reduction). Scenario analyses showed that pen-level colistin treatment effectively reduces the risk from 5.5% to 4.7% (14.5% reduction), an effect similar to stoppage of therapeutic colistin (16.4% reduction to 4.6%).

The Food Safety Commission of Japan (FSCJ) conducted a risk assessment of betamethasone (CAS No. 37-44-9), a synthetic adrenocortical hormone, based on the documents including assessment reports from the European Medicines Evaluation Agency (EMEA). Among results of various studies, a no-observed-adverse-effect level (NOAEL) of betamethasone (as betamethasone dipropionate) was shown as 0.02 mg/kg bw per day in a fertility and early embryonic development study in rats. FSCJ concluded that it is appropriate to set an acceptable daily intake (ADI) of betamethasone by applying the same ADI as dexamethasone. The ADI for dexamethasone at 0.01 μg/kg bw per day (0.00001 mg/kg bw/day) was specified based on the NOAEL of 0.001 mg/kg bw per day of the endocrine toxicity study in rats¹⁾. Consequently, FSCJ specified the ADI for betamethasone at 0.01 μg/kg bw per day.

FSCJ conducted a risk assessment of an antimicrobial, flumequine (CAS No. 42835-25-6), based on reports of JECFA (Joint FAO/WHO Expert Committee on Food Additives) and EMEA (European Medicines Agency) and other documents including the mechanism for liver tumor. Data used in the assessment include pharmacokinetics, acute toxicity, subacute toxicity, chronic toxicity/carcinogenicity, reproductive toxicity, genotoxicity, and microbiological effects. FSCJ specified the ADI of flumenquine as 0.071 mg/kg bw per day, that is the microbiological ADI calculated using the equation for VICH.