An extensive review of arsenic dynamics and its distribution in soil-aqueous-rice plant systems in south and Southeast Asia with bibliographic and meta-data analysis

Arsenic contamination in rice: a DPSIR analysis with a focus on top rice producers

Arsenic contamination in rice poses significant risks to public health and food security. While previous reviews have examined specific aspects of this issue, they often lack a comprehensive analysis linking human activities to arsenic contamination and its broader consequences. This review applies the DPSIR (Driving Forces-Pressures-States-Impacts-Responses) framework to elucidate the cause-and-effect relationships of arsenic contamination in rice, with a focus on top rice producers. It also synthesizes current knowledge on the environmental sources, fate, and transport of arsenic across different environmental compartments, illustrating its movement from emission sources to accumulation in rice while highlighting the complex interplay between environmental conditions, rice varieties, and contamination levels. The DPSIR analysis revealed that socioeconomic factors, including population growth and industrialization, were the primary driving forces behind arsenic contamination in rice. These factors increased pressures such as reliance on arsenic-contaminated irrigation water, historical pesticide use, and industrial pollution, which contributed to arsenic accumulation in rice-growing environments. Consequently, the soil, water, and rice were contaminated with arsenic at various levels, posing serious risks to human health. The impacts extend beyond health concerns to disruptions in global rice trade and threats to food security. In response, various mitigation strategies have been implemented, including regulation, sustainable agricultural practices, water and soil remediation, and public guidance. However, challenges persist, requiring an integrated approach that incorporates scientific advancements, policy interventions, and improved agricultural techniques. Key research priorities include developing arsenic-resistant rice varieties, assessing health risks for vulnerable populations, quantifying economic losses, and determining arsenic-related foodborne diseases burden.

Impact of chronic exposure to ternary metal mixtures on behavioral and cellular responses in Nauphoeta cinerea nymphs

There is a  growing concern about the impact of environmental contamination by metals on insects owing to their biodiversity and important ecological roles. We investigated the neurobehavioral traits, cellular responses, and levels of metals in tissues of Nauphoeta cinerea nymphs exposed, separately and in ternary mixtures, to arsenic (15 and 7.5 mg/L), copper (15 and 7.5 mg/L), and zinc (100 and 50 µg/L), in drinking water for 35 consecutive days. Results showed that the diminutions in locomotor parameters (maximum speed, motility time, and distance traveled), motor and turning capabilities (path efficiency, turn angle, and body rotation) and the increase in anxiety-like behavior (total time freezing and freezing episodes) were more pronounced in individual metal exposure than triple metal mixtures groups. Barring zinc alone group, acetylcholinesterase activity decreased significantly in all the treatment groups compared to the control. The diminutions in glutathione level and antioxidant enzyme activities were partially attenuated in the fat body, midgut, and head of insects in the triple metal mixtures groups. Further, the levels of nitric oxide, hydrogen peroxide, lipid peroxidation, and reactive oxygen and nitrogen species were higher in individual metal exposed insects than the ternary mixture groups. The concentrations of arsenic, copper, and zinc in the fat body, midgut, and head of insects were significantly higher in individual metal exposure groups than the ternary metal mixtures groups. Collectively, the detrimental effects of elevated ecological concentrations of arsenic, copper, and zinc were more pronounced in insects exposed to individual metal than those in ternary mixtures groups.

Recent Advances in Transcriptome Analysis Within the Realm of Low Arsenic Rice Breeding

Arsenic (As), a toxic element, is widely distributed in soil and irrigation water. Rice (Oryza sativa L.), the staple food in Southern China, exhibits a greater propensity for As uptake compared to other crops. Arsenic pollution in paddy fields not only impairs rice growth but also poses a serious threat to food security and human health. Nevertheless, the molecular mechanism underlying the response to As toxicity has not been completely revealed until now. Transcriptome analysis represents a powerful tool for revealing the mechanisms conferring phenotype formation and is widely employed in crop breeding. Consequently, this review focuses on the recent advances in transcriptome analysis within the realm of low As breeding in rice. It particularly highlights the applications of transcriptome analysis in identifying genes responsive to As toxicity, revealing gene interaction regulatory modules and analyzing secondary metabolite biosynthesis pathways. Furthermore, the molecular mechanisms underlying rice As tolerance are updated, and the recent outcomes in low As breeding are summarized. Finally, the challenges associated with applying transcriptome analysis to low-As breeding are deliberated upon, and future research directions are envisioned, with the aim of providing references to expedite high-yield and low-arsenic breeding in rice.

A critical review on the organo-metal(loid)s pollution in the environment: Distribution, remediation and risk assessment

Toxic metal(loid)s, e.g., mercury, arsenic, lead, and cadmium are known for several environmental disturbances creating toxicity to humans if accumulated in high quantities. Although not discussed critically, the organo-forms of these inorganic metal(loid)s are considered a greater risk to humans than their elemental forms possibly due to physico-chemical modulation triggering redox alterations or by the involvement of biological metabolism. This extensive review describes the chemical and physical causes of organometals and organometal(loid)s distribution in the environment with ecotoxicity assessment and potential remediation strategies. Organo forms of various metal(loid)s, such as mercury (Hg), arsenic (As), lead (Pb), tin (Sn), antimony (Sb), selenium (Se), and cadmium (Cd) have been discussed in the context of their ecotoxicity. In addition, we elaborated on the transformation, speciation and transformation pathways of these toxic metal(loid)s in soil-water-plant-microbial systems. The present review has pointed out the status of toxic organometal(loid)s, which is required to make the scientific community aware of this pressing condition of organometal(loid)s distribution in the environment. The gradual disposal and piling of organometal(loid)s in the environment demand a thorough revision of the past-present status with possible remediation strategies prescribed as reflected in this review.

Harness arsenic in medicine: current status of arsenicals and recent advances in drug delivery

INTRODUCTION

Arsenicals have a special place in the history of human health, acting both as poison and medicine. Having been used to treat a variety of diseases in the past, the success of arsenic trioxide (ATO) in treating acute promyelocytic leukemia (APL) in the last century marked its use as a drug in modern medicine. To expand their role against cancer, there have been clinical uses of arsenicals worldwide and progress in the development of drug delivery for various malignancies, especially solid tumors.

AREAS COVERED

In this review, conducted on Google Scholar [1977-2024], we start with various forms of arsenicals, highlighting the well-known ATO. The mechanism of action of arsenicals in cancer therapy is then overviewed. A summary of the research progress in developing new delivery approaches (e.g. polymers, inorganic frameworks, and biomacromolecules) in recent years is provided, addressing the challenges and opportunities in treating various malignant tumors.

EXPERT OPINION

Reducing toxicity and enhancing therapeutic efficacy are guidelines for designing and developing new arsenicals and drug delivery systems. They have shown potential in the fight against cancer and emerging pathogens. New technologies and strategies can help us harness the potency of arsenicals and make better products.

An assessment of the impact of traditional rice cooking practice and eating habits on arsenic and iron transfer into the food chain of smallholders of Indo-Gangetic plain of South-Asia: Using AMMI and Monte-Carlo simulation model

The current study was designed to investigate the consequences of rice cooking and soaking of cooked rice (CR) with or without arsenic (As) contaminated water on As and Fe (iron) transfer to the human body along with associated health risk assessment using additive main-effects and multiplicative interaction (AMMI) and Monte Carlo Simulation model. In comparison to raw rice, As content in cooked rice (CR) and soaked cooked rice (SCR) enhanced significantly (at p < 0.05 level), regardless of rice cultivars and locations (at p < 0.05 level) due to the use of As-rich water for cooking and soaking purposes. Whereas As content in CR and SCR was reduced significantly due to the use of As-free water for cooking and soaking purposes. The use of As-free water (AFW) also enhanced the Fe content in CR. The overnight soaking of rice invariably enhanced the Fe content despite the use of As-contaminated water in SCR however, comparatively in lesser amount than As-free rice. In the studied area, due to consumption of As-rich CR and SCR children are more vulnerable to health hazards than adults. Consumption of SCR (prepared with AFW) could be an effective method to minimize As transmission and Fe enrichment among consumers.