Food safety (Tokyo, Japan)最新文献

Food Safety Commission of Japan (FSCJ) conducted risk assessments of isobutylamine, isopropylamine, sec-butylamine, propylamine, hexylamine, pentylamine and 2-methylbutylamine, which are used as food additives (flavors) (hereinafter, referred to as "the flavoring agents"), based on the Guidelines for the Assessment of Flavoring Substances in Foods on Health (Decision of the Commission Dated May 2016, hereinafter, referred to as the Guidelines on Flavoring Substances), using various documents. Based on the structural and metabolic similarity, FSCJ regarded that the identical procedures are applicable for the risk assessments of all the flavoring agents. FSCJ judged that the seven flavoring agents have no genotoxicities relevant to human health on the basis of the evaluation of analogous compounds. FSCJ metabolized to innocuous products with no food safety concerns. The estimated daily intakes of all the flavoring agents are within the range of 0.02 μg/person per day to 2 μg/person per day, which are below the threshold of concern (i.e., 1,800μg/person per day for Class I), and therefore, FSCJ judged that the flavoring agents are considered to be of no concern for food safety. In summary, FSCJ concluded, as a result of the safety assessment, that there is no safety concern with the flavoring agents, isobutylamine, isopropylamine, sec-butylamine, propylamine, hexylamine, pentylamine, and 2-methylbutylamine, as long as they are used as flavorings in foods.

The Food Safety Commission of Japan (FSCJ) conducted a risk assessment of hexavalent chromium, hereinafter referred to as Cr (VI), related to the amendment of the standards for beverages established by the Ministry of Health, Labour and Welfare. Major toxicities induced by Cr (VI) were damages to small intestine and anemia in experimental animals. The finding observed at the lowest LOAEL was diffuse hyperplasia of mucosal epithelium in the duodenum in mice. Regarding to carcinogenicity, Cr (VI)-treatment by drinking water significantly increased incidences of tumors in the small intestine in mice and in the oral mucosa and tongue in rats. Therefore, FSCJ considered that Cr (VI) is carcinogenic. Cr (VI) showed positive results in many genotoxic studies in vitro, and in vivo after parenteral administration, whereas no clear positive results were obtained after the oral administration. These data indicate the genotoxic properties of Cr (VI), though genotoxicity by the oral administration including drinking water remains unclear. The mechanism of small intestinal tumors in mice is considered as follows: Continuous damage to mucosal epithelium in the small intestine by long-term exposure to Cr (VI) induces the hyperplasia in the crypt of small intestine, which would lead to the formation of tumor. In the in vivo gene mutation assays using transgenic rats and mice, no significant increases in mutant frequencies of the transgenes were observed in the carcinogenic target tissues, after exposure to Cr (VI) in drinking water for either 28 (rats) or 90 days (mice)^{1), 2)}. On the basis of these results, FSCJ judged that the carcinogenic mechanism of Cr (VI) intakes through drinking water was hardly attributable to the genotoxicity. FSCJ considered that the quantitative risk assessment of Cr (VI) through drinking water was difficult to conduct based on the results from epidemiological studies of non-occupational and occupational exposures in human population. Consequently, specifying a tolerable daily intake (TDI), based on the results of animal studies with oral exposure to Cr (VI) through drinking water, is rather feasible. FSCJ specified the TDI of Cr (VI) as 1.1 μg/kg bw/day after applying the uncertainty factor of 100 to BMDL₁₀ of 0.11 mg/kg bw/day, which was ascribed on the diffuse epithelial hyperplasia in the duodenum in male mice observed in the two-year oral exposure study. Since chromium in food is regarded to be present as trivalent chromium³⁾, FSCJ estimated daily intake of Cr (VI) from consumption of mineral water and tap water. The estimation gave the mean and high intakes as ca. 0.04 μg/kg bw/day and 0.290 μg/kg bw/day, respectively. Since both of these two values were lower than the TDI, 1.1 μg/kg bw/day, FSCJ concluded the risk of health effects from Cr (VI) at the current exposure through the consumption of mineral water and tap water to be extremely low.

[This corrects the article DOI: 10.14252/foodsafetyfscj.2018003.].

Bovine spongiform encephalopathy (BSE) is a fatal neurodegenerative disease that belongs to transmissible spongiform encephalopathy (TSE). Since the first case was identified in the UK in 1986, BSE spread to other countries including Japan. Its incidence peaked in 1992 in the UK and from 2001 to 2006 in many other countries, but a feed ban aimed at eliminating the recycling of the BSE agent and other control measures aimed at preventing food and feed contamination with the agent were highly effective at reducing the spread of BSE. In 2004, two types of atypical BSE, H-type BSE (H-BSE) and L-type BSE (L-BSE), which differ from classical BSE (C-BSE), were found in France and Italy. Atypical BSE, which is assumed to occur spontaneously, has also been detected among cattle in other countries including Japan. The BSE agent including atypical BSE agent is a unique food-safety hazard with different chemical and biological properties from the microbial pathogens and toxic chemicals that contaminate food. In this review, we summarize the reported findings on the tissue distribution of BSE prions in infected cattle and other aspects of BSE, as well as the control measures against the disease employed in Japan. Topics that require further studies are discussed based on the summarized findings from the perspective of food safety.

Flies play a key role as vectors in transmitting various bacteria and pose bacterial contamination risk to food. To evaluate the time- and concentration-related bacterial contamination of food by houseflies based on their attraction to the food, we determined the number of fed antimicrobial-resistant Escherichia coli transferred from houseflies to foods, sugar and milk mixture, apple, and castella (such as sponge cake). Houseflies contaminated the foods with the fed E. coli within 5 min, and the bacteria were present in high numbers on apple and castella (3.3 × 10³ and 3.5 × 10⁴ CFU/g of food, respectively). Furthermore, the number of fed E. coli on the foods increased with time, rising to 3.6 × 10⁴-1.7 × 10⁵ CFU/g. We show that the food contamination level caused by houseflies depends on the concentration of bacteria that the houseflies carry, the contact time with the food, and the attraction of the flies to the food.

The Food Safety Commission of Japan (FSCJ) conducted a risk assessment of flubendiamide (CAS No. 272451-65-7), an iodophthalimide insecticide for the setting of an acceptable daily intake (ADI) in 2006. FSCJ now has assessed this insecticide for the setting of an acute reference dose (ARfD). Data including fate in animals (rats and mice) and residues in crops (burdock roots, pumpkins and others) were newly submitted. Major adverse effects of flubendiamide include hepatocellular hypertrophy, fatty changes in hepatocytes, follicular epithelial cell hypertrophy in thyroid and ocular enlarged eye in rats. No neurotoxicity, carcinogenicity, reproductive toxicity, teratogenicity, neurodevelopmental toxicity and genotoxicity were observed. The lowest no-observed-adverse-effect level (NOAEL) in the toxicological studies was 1.70 mg/kg body weight/day in a two-year carcinogenicity study in rats. FSCJ confirmed an ADI of 0.017 mg/kg bw/day after applying a safety factor of 100 to the NOAEL. Adverse effects elicited by a single oral administration of flubendiamide would be abnormalities in eyes such as ocular hypertrophy and iris adhesion in offspring, which were obtained in a two-generation reproductive toxicity study, a one-generation reproductive toxicity study and a neurodevelopmental toxicity study in rats. FSCJ judged that these studies may be applicable to set the ARfD for lactating women in relation to the exposure of flubendiamide to offspring after the birth through breast milk. By taking into account the overall evaluations of the two-generation reproductive toxicity study, one-generation reproductive toxicity study and neurodevelopmental toxicity study in rats, FSCJ judged NOAEL of 15.0 mg/kg bw/day as for an overall NOAEL, and consequently specified an ARfD of 0.15 mg/kg bw/day for lactating women by applying a safety factor of 100 to the NOAEL.

The in vivo mutagenicity of hexavalent chromium in the small intestine, the target organ of tumorgenicity, was examined by means of a transgenic mouse gene mutation assay. Sodium dichromate dihydrate was administered orally in drinking water to male gpt delta mice at a dose of 85.7 or 257.4 mg/L for 28 days or at a dose of 8.6, 28.6 or 85.7 mg/L for 90 days. No significant increase in gpt mutant frequency relative to that in control mice was observed in the small intestine in either the 28- or 90-day study, whereas 28-day oral administration of potassium bromate, a positive control substance, increased mutant frequency.

The Food Safety Commission of Japan (FSCJ) conducted a self-tasking assessment of mycotoxins, fumonisin B1 (FB1 CAS No. 116355-83-0), fumonisin B2 (FB2 CAS No. 116355-84-1), and fumonisin B3 (FB3 CAS No. 136379-59-4). Hepatotoxicity and/or nephrotoxicity were commonly observed in experimental animals given orally purified FB1, and the sex-related differences were observed in rats and mice. Species differences were also identified: Increased incidences of liver tumors in female mice and of kidney tumors in male rats were observed in chronic toxicity/carcinogenicity studies. Fumonisins did not show appreciable genotoxicity both the in vivo and in vitro tests. FSCJ judged fumonisins as non-genotoxic carcinogens from the results of various toxicological studies on fumonisins, and thus specified a tolerable daily intake (TDI) of 2 μg/mg bw/day for fumonisins (FB1, FB2 and FB3, alone or by combination), after applying an uncertainty factor of 100 to the lowest no-observed-adverse-effect level (NOAEL) of 0.21 mg/kg bw/day in subacute toxicity study in rats. The estimated exposure levels of fumonisins among high consumers such as toddlers are still below the TDI. Therefore, FSCJ concluded that adverse effect of fumonisin on human health through food are unlikely under the current situation in Japan.