Ochratoxin A (OTA) is a naturally occurring mycotoxin produced by Aspergillus and Penicillium fungi that can contaminate a range of agricultural commodities and products, such as cereal grains, dried fruit, and coffee beans. While some OTA contamination in foods may be unavoidable, there are steps that can be taken to help prevent fungal growth and control the presence of OTA in foods. The U.S. Food and Drug Administration (FDA) has established a regulatory mycotoxin compliance program to sample and analyze human foods for mycotoxins. Each year, under this compliance program, samples of foods susceptible to mycotoxin contamination are collected and analyzed for various mycotoxins, including OTA. In this study, we present and discuss data on OTA levels for over 3,700 food samples collected between fiscal years (FY) 2008 and 2022. OTA levels ranged from non-detect to 116 µg/kg, with the highest findings seen in green coffee beans, dried fruits, grain products, and spices. The vast majority of samples (96.5%) had OTA levels below the levels of quantification (LOQs) of 0.21 to 24.9 µg/kg. The findings were similar to detection rates, levels, and affected foods seen in other surveys of OTA. Our findings support continued monitoring of OTA in susceptible foods and may be useful in future work to determine whether it is appropriate to establish regulatory levels for OTA in the United States.

Assessing the prevalence of foodborne pathogens in the environment is an important step toward mitigating those risks. In this comprehensive two-year study, we assessed the occurrence of human norovirus (NoV) and hepatitis A virus (HAV) in agricultural water used for crop irrigation to better understand potential sources of contamination, which can contribute to outbreaks caused by these viruses. For the first series of experiments, samples of surface and ground water were collected monthly during the growing seasons from 36 sites, representing 21 farms in two regions in the US, namely Georgia (GA) and Ohio (OH). Two primary concentration methods were employed to capture naturally occurring viruses from 10L of water: either dead-end hollow fiber ultrafiltration (DEUF) or modified Moore swab (MMS). For secondary virus concentration, DEUF was coupled with polyethylene glycol (PEG) precipitation, while MMS was paired with ultracentrifugation. The detection rate using RT-qPCR was 8.4% for NoV genogroup II (NoV-GII) and 9.4% for HAV, found across 24 sampling sites on 15 farms. We then directly compared the performance of DEUF and MMS for virus recovery by concentrating 10 L of agricultural water spiked with NoV with each method. The DEUF consistently provided both higher detection rates and lower Ct values across various levels of virus spiking (p < 0.05 at the seeding level of 5.0E+05 genome copies/10L). There were no significant differences in virus recovery between the two secondary concentration methods (PEG or ultracentrifugation). Improving methods for obtaining surveillance information will provide greater insights into the prevalence of human enteric viruses in irrigation water and support the development of viral pathogen mitigation strategies in the prevention of foodborne outbreaks.

This study aimed to clarify the scientific basis for deriving Tolerable Daily Intake (TDI) values in risk assessments conducted by the Food Safety Commission of Japan (FSCJ), with a particular focus on the types of studies used, uncertainty factors (UFs), and critical effect levels (No-Observed-Adverse-Effect Levels and Lowest-Observed-Adverse-Effect Levels).

We reviewed 77 chemical risk assessment reports published by the FSCJ as of October 2022. Using a standardized data extraction template developed with reference to the ATSDR and IRIS formats, ten trained reviewers examined and coded relevant toxicological information. In total, 46 reports were included in the final analysis.

Most TDI values (73.9%) were derived from animal studies and were typically accompanied by large UFs ranging from 100 to 1000. Human-based TDIs derived from human observational (15.2%) and human intervention (10.9%) studies accounted for a smaller proportion but were generally associated with higher TDI values and smaller UFs. The examination of the NOAEL and LOAEL distributions indicated that lower exposure thresholds were primarily based on human study, whereas higher thresholds predominantly relied on animal studies.

The derivation of TDI in Japan relies predominantly on animal study. Enhancing the availability of high-quality human data and improving consistency in the application of UFs may strengthen the transparency and scientific validity of health-based guidance in the future.

Pufferfish in the genus Takifugu accumulate the potent neurotoxin tetrodotoxin (TTX) in specific tissues that vary by species; nevertheless, certain species are consumed as a luxury food in Japan. Therefore, the edible species and tissues of Takifugu pufferfish are regulated in Japan. In recent years, unidentifiable individuals with atypical morphological characteristics caught in waters around Japan have been found to be natural interspecific hybrids among Takifugu species. Four cases of natural hybridization have been reported; in all cases, hybrids had external characteristics intermediate between those of the parental species. Although the frequency of these hybrids was generally low, it is high in certain parental species combinations. The TTX accumulation in tissues of natural and artificial hybrids was investigated and it was inferred that TTX accumulation in the skin is dominantly inherited. However, information on hybrids’ toxicity in Takifugu pufferfish remains insufficient, and further research is required to prevent TTX poisoning associated with them.

Food Safety Commission of Japan (FSCJ) conducted a risk assessment of oxolinic acid (CAS No. 14698-29-4), an antimicrobial agent with a quinoline structure, based on results from submitted documents. For the fifth edition, additional residue data for crops (including taro and broccoli) were submitted by the Consumer Affairs Agency. The data used in the assessment include fate in animals (including rats) and humans, fate in plants (including paddy rice and napa cabbage), residues in crops, residues in livestock products (including cattle and pigs), subacute toxicity (rats, mice, and dogs), chronic toxicity (dogs), combined chronic toxicity/carcinogenicity (rats), carcinogenicity (mice), two-generation reproductive toxicity (rats), developmental toxicity (rats and rabbits), and genotoxicity. Major adverse effects of oxolinic acid were observed in the body weight (suppressed weight gain), the testes (interstitial cell hyperplasia in rats), the ovaries (organ weight increase in rats), excitatory neurological symptoms, and behavioral changes (Table 1). No adverse effects were observed on either fertility, teratogenicity, or biologically significant genotoxicity. The lowest NOAEL for potential adverse effects after a single oral administration of oxolinic acid was 6 mg/kg bw from the results of the acute neurotoxicity study in rats (Table 2). FSCJ established an acute reference dose (ARfD) of 0.06 mg/kg bw by applying a safety factor of 100 to this NOAEL.