The health and environmental impact of toxic metals in agricultural soils pose a major global challenge, necessitating continuous monitoring of their levels. These hazardous materials present a significant threat to food safety as they can be taken up by crops. Among the prevalent toxic metals that are known to be toxic to humans and aquatic and terrestrial animals are mercury (Hg) and cadmium (Cd). These metals have the potential to be hazardous even at low concentrations, a fact that can be exacerbated by repeated exposure and the prevalence of these hazardous metal combinations in the environment. Reports on the global distribution and concentration of toxic metals are not only crucial for protecting ecosystems but also for evaluating the broader environmental impact and ensuring public health safety. Therefore, the aim of this chapter was to give an overview of the occurrence of Hg and Cd in the agricultural soils and their accumulation levels in cereal grains planted in contaminated soils based on studies conducted worldwide between 2018 and 2024. In some countries, levels of Hg in agricultural soils and Cd in cereal grains have been reported to be above the maximum allowable limits set by regulatory authorities, particularly in samples collected near mining and industrial sites that release toxic metals into the environment. This may pose a serious public health risk. However, because the studies included in this chapter are small-scale and isolated, they do not offer a thorough picture of the levels of harmful metals throughout the world. The development of efficient solutions to mitigate the emission of hazardous metals is imperative in order to safeguard the environment and public health by reducing their accumulation in the environment and downstream ecosystems. Developing nations should pay special attention to this because they are still lagging behind. Additionally, the monitoring of dangerous metal concentrations necessitates the use of quick and accurate analytical techniques.