We investigated the cadmium content in soils and rice in Cha Hayang, Wuchang, Fangzheng, Xiangshui, and Jiansanjiang areas of Heilongjiang Province, and characterized the effect of rice intake on human health. The samples were analyzed by ICP-MS, and the cadmium transfer in soil-rice system was modeled by the Nemero comprehensive pollution index method. The health risk assessment model was used to study the status of cadmium pollution in rice and its health risk assessment for adults and children. The results showed that the average contents of cadmium in rice were 0.003 (Cha Hayang), 0.016 (Wuchang), 0.006 (Fangzheng), 0.006 (Xiangshui), and 0.005 (Jiansanjiang) mg kg-1. The prediction model developed in this study, including the total heavy metals and pH value of the soil, effectively described the transfer of cadmium in the soil-rice system of Wuchang, Chahayang and Xiangshui paddy fields (with R2 between 0.256 and 0.468). The pollution index of the study area was less than 1. The comprehensive pollution index was 0.037<1, sugesting no pollution, and the comprehensive pollution index was between 0.059 and 0.158. The health risk index of carcinogenic heavy metal cadmium to adults and children in Cyang and JianSanjiang areas was lower than that recommended by USEPA (1 × 10-4), suggesting no risk of cancer. However, the mean values in Wuchang, Fang Zheng and Xiangshui were higher than the maximum acceptable risk recommended by USEPA, suggesting a risk of cancer.

The diversity of fungi in barley in simulated storage environments was analyzed. Barley was stored at different temperatures (15, 25, 35°C) and relative humidity (55, 65, 75, 85 RH) for 180 and 360 days. Alpha diversity, beta diversity, species composition, and species differences were analyzed using Illumina HiSeq technology. The fungal communities in all barley samples before and after storage belonged to 3 phyla, 18 classes, 39 orders, 71 families, 103 genera, and 152 species. The relative abundance of the dominant phylum Ascomycota was 77.98–99.19%. The relative abundance of Basidiomycota was 0.77–21.96%. At the genus level, the dominant genera of fungi in barley initially included Fusarium, Aspergillus, Microdochium, Alternaria, and Epicoccum. After 360 days of storage, the dominant genera became Epicoccum, Alternaria, Bipolar, Cladosporium, Fusarium, and Aspergillus. According to Venn diagrams and principal coordinates analysis, the fungal community diversity in barley initially was much higher than in barley stored at different temperatures and humidity. The application of PLS-DA could accurately distinguish between barley stored for 180 and 360 days. Some high-temperature and high-humidity environments accelerated storage. The dominant genera differed in different storage conditions and constantly changed with increasing storage duration. Epicoccum was one of the dominant genera after longer storage periods. This study provides theoretical support for optimizing safe storage conditions in barley.

In order to explore the distribution and transfer of lead elements in soil and rice in the five regions of Chahayang, Wuchang, Fangzheng, Xiangshui and Jiansanjiang in Heilongjiang Province, and analyze the impact of rice intake on human health, the samples were tested by ICP-MS. Modeling the lead-element transfer in the soil-rice system, using the Nemero comprehensive pollution index method and the health risk assessment model to evaluate the lead pollution status of rice in the study area and its health risks to adults and children. The results showed that the average content of lead in rice in the study area was Chahayang 0.02 mg/kg, Wuchang 0.03 mg/kg, Fangzheng 0.017 mg/kg, Xiangshui 0.023 mg/kg and Jiansanjiang. 0.024 mg/kg did not exceed the lead content limit specified by China's National Food Hygiene Standard (0.2 mg/kg); Based on the prediction model of heavy metal lead content, pH value, and organic matter in the soil, the transfer of lead elements in the soil-rice system of Chahayang, Fangzheng, Xiangshui, and Jiansanjiang rice fields can be significantly described, with R 2 values ranging from 0.224 to 0.419; Both the pollution index and the comprehensive pollution index in the study area were less than 1, which belong to the non-pollution category. The health risk index of heavy metal lead for adults and children in all five regions is lower than the maximum acceptable risk level recommended by USEPA, and there is no risk of causing cancer.

At present, fomesafen is widely used to control weeds in Vigna angularis fields. To explore the effect of fomesafen (FSA) on the nutritional value and amino acids of Vigna angularis, the protein, fat, water, ash, sand yield, and hundred-grain weight of Vigna angularis were measured using Vigna angularis sprayed with or without FSA. A non-targeted metabonomics and a high-throughput targeted amino acid analysis of Vigna angularis were performed using the metabonomics technology of liquid chromatography–mass spectrometry (LC-MS). The results showed that the protein (23.39 ± 0.16%) and fat (0.49 ± 0.05%) in sprayed Vigna angularis (Z-2-GS-2) were significantly different from the protein (19.88 ± 0.05%) and fat (0.71 ± 0.06%) in non-sprayed Vigna angularis (GS), indicating that a certain amount of FSA could promote the synthesis of protein in Vigna angularis and inhibit the formation of fat. A total of 63 metabolites with significant differences were screened from the non-targeted metabonomic analysis, including isoprene lipids, carboxylic acids, organic oxygen compounds, and carboxylic acid derivatives. Seventeen metabolic pathways were enriched. Five metabolic pathways with significant differences were screened according to p < 0.05, including alanine, aspartic acid, glutamic acid metabolism, tryptophan metabolism, and arginine biosynthesis, indicating that FSA had a significant effect on amino acid metabolism in Vigna angularis. Through targeted amino acid analysis, 21 different amino acids in Vigna angularis were accurately determined qualitatively and quantitatively. Among them, the contents of Asp and Glu increased under the influence of FSA, while the contents of Phe, His, and Ile decreased, which proved that FSA would cause the sweet taste of Vigna angularis to increase, reducing the flavor. Use of FSA will lead to the increase in protein content, ash content, and sand yield of Vigna angularis, while also leading to the decrease of fat content, water content, and hundred-grain weight. The use of FSA will also have a particular impact on the nutritional value, health care efficacy, and taste of Vigna angularis. The results of this study provide new ideas for follow-up research on the rational use of FSA in the field of Vigna angularis and the development of Vigna angularis health food.