A mining district in south China shows significant metal(loid) contamination in paddy fields. In the soil, Pb, Cd and As were 516.7, 11.7 and 35.1 mg•kg-1 respectively. The content of Cd exceeded the environmental quality standard for agricultural soils in China by approximately 82%. The contents of Pb, Cd and As in rice were 22.7, 1.1 and 0.7 mg•kg-1 respectively. These concentrations are also higher than the agricultural industry standard of China for rice. The elevated contents of Pb, Cd and As detected in soils around the factories, indicated that their spatial distribution was influenced by anthropogenic activity. Greater concentrations of Cd in rice appeared in the northwest region of the factories, indicating that the spatial distribution of heavy metals was affected by natural factors. The metals affected the viability of HepG2 and KERTr cells, which decreased with increasing metal concentration. Co-exposure to heavy metals (Pb+Cd) increased the metals (Pb or Cd)-mediated MT protein induction in both human HepG2 and KERTr cells. Increased levels of MT protein will lead to greater risk of carcinogenic manifestations, and it is likely that chronic exposure to metals may increase the risk to human health. Nevertheless, when co-exposure to two or more metals occur (such as As+Pb), they may have an antagonistic effect thus reducing the toxic effects of each other.

Sterigmatocystin (STG), a biosynthesis precursor of aflatoxin B1, is well known for its toxic and carcinogenic effects in humans and animals. STG derivatives and protein conjugates are needed for generation of monoclonal antibodies (mAbs). This work describes a reliable and fast synthesis of novel STG derivatives, based on which novel STG bovine serum albumin conjugates were prepared. With the novel STG bovine serum albumin conjugates, three sensitive and specific mAbs against STG, named VerA 3, VerA 4, and VerA 6, were prepared by semi-solid hypoxanthine/aminopterin/thymidine (HAT) medium using a modified two-step screening procedure. They exhibited high affinity for STG and no cross-reactivity (CR) with aflatoxins B1, B2, G1, G2, and M1. Based on the most sensitive antibody VerA 3, an ultra-sensitive competitive enzyme-linked immunosorbent assay (ELISA) was developed for STG in wheat, maize, and peanuts. Assays were performed in the STG-GA-BSA-coated (0.5 µg·mL−1) ELISA format, in which the antibody was diluted to 1∶80,000. Several physicochemical factors influencing assay performance, such as pH, ionic strength, blocking solution, and diluting solution, were optimized. The final results showed that the assays had the detection limits of 0.08 ng·g−1 for wheat, 0.06 ng·g−1 for maize, and 0.1 ng·g−1 for peanuts, inter-assay and intra-assay variations of less than 10%, and recoveries ranging from 83% to 110%. These recoveries were in good agreement with those obtained by using HPLC-MS/MS method (90–104%), indicating the importance of the mAb VerA 3 in the study of STG in crude agricultural products.

A simple and direct arylation of benzothiazoles in the presence of diaryliodonium salts to afford 2‐arylbenzothiazoles has been developed. This cross‐coupling reaction is catalyzed by palladium bromide in the presence of cesium carbonate and a phosphorus ligand. The protocol has a broad substrate scope and is tolerant towards a wide range of functional groups to give the desired products in moderate to high yields.

A one‐step, cheap and practical manganese‐mediated aerobic oxidative olefination of (het)arenemethanols with acetonitrile to highly steroselectively prepare trans‐cinnamonitrile derivatives in good yield is developed. For benzyl alcohols, the trans‐products were obtained exclusively. The convenient method of this C=C bond formation has an wide substrate scope and a highly atom utility. Control experiments showed that synergetic oxidative effect of manganese dioxide and oxygen and Mn‐promoted Knoevenagel condensation thereafter make the reaction proceed smoothly.