Search

In acidic paddy fields of South China, rice (Oryza sativa L.) faces the dual challenges of cadmium (Cd) toxicity and silicon (Si) deficiency. Although previous studies have highlighted the functions of Si application timing and strategies in mitigating Cd-stressed rice, the precise mechanisms underlying the health restoration of Cd-toxic rice and the assurance of grain safety remain elusive. This study explored Cd translocation and detoxification in the shoots of rice regulated by various Si fertilization regimes: Si(T) (all Si added before transplanting), Si(J) (all Si added at jointing), and Si(TJ) (half Si added both before transplanting and at jointing). The findings revealed that the regime of Si(TJ) was more beneficial to rice health and grain safety than Si(T) and Si(J). The osmotic regulators such as proline, soluble sugars, and soluble proteins were significantly boosted by Si(TJ) compared to other Si treatments, and which enhanced membrane integrity, balanced intracellular pH, and increased Cd tolerance of rice. Furthermore, Si(TJ) was more effective than Si(T) and Si(J) on the Cd sequestration in the cell wall, Cd bio-passivation, and the down-regulated expression of the Cd transport genes. The concentrations of Cd in the xylem and phloem treated with Si(TJ) were reduced significantly. Additionally, Si(TJ) facilitated much more Cd bound with the outer layer proteins of grains, and promoted Cd chelation and complexation by phytic acid, phenolics, and flavonoids. Overall, Si (TJ) outperformed Si(T) and Si(J) in harmonizing the phycological processes, inhibiting Cd translocation, and enhancing Cd detoxification in rice plant. Thereby the split Si application strategy offers potential for reducing Cd toxicity in rice grain. [ABSTRACT FROM AUTHOR]

Ceramic products are among the most frequently used food contact materials. Health risks associated with ceramic tableware usually arise from the migration of heavy metals. In this study, 767 pieces of ceramic tableware of different shapes and types were collected across China, and the migration levels of 18 elements were determined using inductively coupled plasma mass spectrometry. Migration tests were conducted according to the Chinese National Food Safety Standard – Ceramic Ware (GB 4806.4) with microwaveable and non-microwavable samples under different conditions. The food consumption of consumers via different shapes of ceramic tableware was obtained through a self-reported web-based survey, and the estimated dietary intakes of the studied elements were calculated accordingly. The exposure assessment showed that certain metals leached from the ceramic tableware at levels of concern. In addition, the applicability of the migration experiment conditions for microwaveable ceramic ware in GB 4806.4 needs to be further investigated. [ABSTRACT FROM AUTHOR]

Urban surface deposited sediments (USDS) are unique indicators of local pollution that pose a potential threat to the living environment and human health. Ekaterinburg is a highly populated metropolitan area in Russia with rapid urbanization and industrialization activities. In Ekaterinburg's residential areas, about 35, 12, and 16 samples are represented by green zones, roads, driveways, and sidewalks, respectively. The total concentrations of heavy metals was detected using a chemical analyzer inductively coupled plasma mass spectrometry (ICP-MS). Zn, Sn, Sb, and Pb have the highest concentrations in the green zone, while V, Fe, Co, and Cu represent the utmost values on roads. Moreover, Mn and Ni are the prevailing metals in the fine sand fraction of driveways along with sidewalks. Broadly, the high pollution in the studied zones is generated by anthropogenic activities and traffic emissions. The potential ecological risk (RI) was observed in high risk (IR > 600), even though the results of all heavy metals reveal no adverse health effects from the considered noncarcinogenic metal for adults and children by different exposure pathways except the children's exposure to Co in case of the dermal contact, where the HI values of Co for children in the studied zones are higher than the proposed level (> 1). In all urban zones, the total carcinogenic risk (TLCR) values are predicted as a high potential inhalation exposure., (© 2023. The Author(s), under exclusive licence to Springer Nature B.V.)