Arsenic concentrations in local aromatic and high-yielding hybrid rice cultivars and the potential health risk: a study in an arsenic hotspot

Abstract

The presence of high levels of arsenic (As) in rice fields has negative effects on the health of those consuming rice as their subsistence food. This study determined the variation in total As concentration in local aromatic rice (LAR) (kalijira) and two high-yielding varieties (HYVs) (BRRI dhan 32 and BRRI dhan 28) grown in paddy fields in Matlab, Bangladesh, an As hotspot with elevated As levels in groundwater. Mature rice grain samples and soil samples were collected from different paddy fields, and the As concentrations in both the de-husked grains and the husks of the three rice cultivars were analysed to identify the safest of the three cultivars for human consumption. The results showed that the total As concentration was higher (0.09–0.21 mg As kg−1) in the de-husked grains of LAR than in the husks, while the opposite was found for the HYV rice. Moreover, the As concentration in soil samples was 2 to 5-fold higher for the LAR than for the HYVs, but the As accumulation factor (AF) was lower in the LAR (0.2–0.4%) than in the HYVs (0.9–1%). Thus, LAR can be considered the safest of the three cultivars for human consumption owing to its low AF value. Furthermore, due to the low AF, growing LAR instead of HYVs in soils with slightly elevated As levels could help improve the food safety level in the food chain.

Arsenic accumulation in rice (Oryza sativa L.) is influenced by environment and genetic factors

“…Rice and rice-based products with high As concentrations may increase health risk for the humans (Sandhi et al, 2017;Signes-Pastor et al, 2016). The level of total As and As species in rice grains are depended on the rice genotype, physico-chemical, and environmental interactions as summarized in Table 4.…”

Arsenic in the water and agricultural crop production system: Bangladesh perspectives

“…This arsenic exposure is due to growing food crops in arsenic-contaminated soil and/or irrigated with arsenic-contaminated groundwater. In Bangladesh, rice is one of the major agronomic crop varieties, covering up to 75% of total agricultural land and requiring 83% of irrigation water (Sandhi et al 2017 ). The use of As-contaminated irrigation water in Bangladesh has been found to be the main cause for the accumulation of this carcinogenic metalloid in the food crops (Das et al 2009 ).…”

“…However, arsenic-related human health risks and their analysis through rice consumption not only depend on the rice varieties, arsenic content in the soil and irrigation water of those cultivated rice fields, and their arsenic AF (accumulation factor, metal/metalloid concentration ratio of plant to soil). A field study conducted in Matlab, Bangladesh, showed that arsenic content in the de-husked grain of hybrid rice cultivars was low compared to the local aromatic rice cultivar and that it could reduce health risk through rice consumption; however, they have a higher accumulation factor than the local rice varieties (Sandhi et al 2017 ). Therefore, the rice cultivars high arsenic AF could increase arsenic ingestion in the human food chain more if they have been cultivated in As-rich environments (soil and groundwater).…”

“…Long-term exposure to As could cause a number of chronic diseases, including but not limited to skin lesions, skin cancer, kidney, lung, bladder, hypertension, cardiovascular diseases, and DNA methylation (Rahman et al 2015 ; Smith et al 2000 ; Saha and Rahman 2020 ; Ljung et al 2011 ). Strongly elevated levels of arsenic (< 0.5– > 4600 µg/L) have been found in the groundwater systems in several regions of Bangladesh and are considered to be one of the major environmental disasters of this South-East Asia region (Huq et al 2020 ; Rahman et al 2019b ; Sandhi et al 2017 ; Smith et al 2000 ). Arsenic poisoning (via e.g., drinking water) poses significant public health concerns for Bangladesh and is estimated to affect about 35–77 million inhabitants throughout the country (Rahman et al 2018 ; Smith et al 2000 ).…”

Heavy metals as environmental risk factors for cardiovascular diseases: from the perspective of the renin angiotensin aldosterone system and oxidative stress

“…Drinking water contamination caused by As is a public health problem in several countries such as Bangladesh, Vietnam and Chile (Smith et al, 2000;Nordstrom, 2002). Recent investigations reported the presence of As in rice grains grown in As prone areas (Sandhi et al, 2017;Maher et al, 2018), heavy metal contamination in fruits and vegetables (Shaheen et al, 2016;Massadeh and Al-Massaedh, 2018) and in soils near an electronics manufacturing facility (Wu et al, 2018).…”