Rice Grain Cadmium Concentrations in the Global Supply-Chain

Abstract

One of cadmium's major exposure routes to humans is through rice consumption. The concentrations of cadmium in the global polished (white), market rice supply-chain were assessed in 2270 samples, purchased from retailers across 32 countries, encompassing 6 continents. It was found on a global basis that East Africa had the lowest cadmium with a median for both Malawi and Tanzania at 4.9 μg/kg, an order of magnitude lower than the highest country, China with a median at 69.3 μg/ kg. The Americas were typically low in cadmium, but the Indian sub-continent was universally elevated. In particular certain regions of Bangladesh had high cadmium, that when combined with the high daily consumption rate of rice of that country, leads to high cadmium exposures. Concentrations of cadmium were compared to the European Standard for polished rice of 200 μg/kg and 5% of the global supply-chain exceeded this threshold. For the stricter standard of 40 μg/kg for processed infant foods, for which rice can comprise up to 100% by composition (such as rice porridges, puffed rice cereal and cakes), 25% of rice would not be suitable for making pure rice baby foods. Given that rice is also elevated in inorganic arsenic, the only region of the world where both inorganic arsenic and cadmium were low in grain was East Africa.

The Effects of Cadmium Toxicity

“…Vegetarians and shellfish consumers may be exposed to a higher cadmium intake than omnivores [32]. One of the major routes for cadmium exposure in humans is through rice consumption [33]. For this reason, flooding rice fields at harvest time is recommended as a water management strategy for reducing Cd accumulation in rice, especially in Japan, in areas where there is soil contamination of Cd; this strategy may, however, increase As accumulation in rice [34,35].…”

Assessment of alkalinity on the adsorption of cadmium ion using KOH-activated carbon from Sesame stem

“…From the figure, the equilibrium adsorption was attained after about 60 min for the activated carbon powders with adsorption capacities of 86.68 KOH-AC. A general observation was that before equilibrium, there was rise in the removal efficiency of Cd2+ by KOH-AC with increasing contact time which is universally true for good adsorbents [9]. The major shift was observed between 1-2 hours.…”

Differential Expression Profiles and Potential Intergenerational Functions of tRNA-Derived Small RNAs in Mice After Cadmium Exposure

“…Cadmium (Cd) is a toxic heavy metal and ubiquitous environmental endocrine disruptor (EDC), which is widely present in contaminated foods, water, soil and air at low concentrations ( Sirot et al, 2008 ; Järup and Åkesson, 2009 ; Satarug, 2018 ; Genchi et al, 2020 ; Shi et al, 2020 ). Notably, smoking is an increasingly important route to Cd exposure ( Faroon et al, 2012 ; Taha et al, 2018 ).…”