Researchers studied how different types of soil, soil pH levels, and soil metals affect the accumulation of arsenic and cadmium in rice grown in Malawi. They found that the type of soil, its pH, and the presence of certain metals in the soil can impact the levels of arsenic and cadmium in rice grains. The highest arsenic levels were found in rice from the central region grown in specific soil types, while the highest cadmium levels were detected in rice from the same region but in different soil conditions. The study showed that soil type, pH, and metal content all play a role in determining the levels of these harmful substances in rice.