Abstract <p>A field study was conducted in arsenic (As) affected regions of the Middle Ganga Plain (MGP), focusing on sixteen commonly cultivated wheat and rice cultivars across three agro-climatic zones with varying As concentrations in irrigation water and soil. The aim of the study was to assess the extent of As contamination in these major cereals and to explore their potential association with cancer risk in local populations. The study revealed that As concentrations in rice grains were up to three fold higher than in wheat, depending on total As (<i>t</i>As) levels in irrigation water, edaphic factors and crop genotypes. Its accumulation in grains was influenced by both the maturity time and plant height of the cultivar. Dwarf and semi-dwarf cultivars with shorter maturity periods accumulated approximately half As in comparison to tall and long duration cultivars. These effects were more pronounced in wheat than in rice. Phenolic accumulation was generally higher in rice than in wheat, however, cultivar specific variation dominated among the two cereals. Levels of these compounds were closely related to As accumulation in grains, where gallic acid showed a negative correlation with As accumulation, while other phenolic compounds, such as benzoic acid, coumaric acid, sinapic acid, kaempferol, and caffeic acid, exhibited strong positive correlations in wheat grains. Cumulative As intake from wheat or rice based diets, coupled with the use of As laden water for dough preparation and rice cooking, can significantly increase potential cancer risk (i.e. &gt;&#xa0;80 times higher than the base line of US EPA) in local populations. However, proper rinsing of rice (before cooking) and wheat (before flour preparation) grains in a 1:3 rice/wheat to water ratio could significantly reduce the cancer risk. Furthermore, the cultivation of short duration cultivars and rinsing their grains may lead to an average reduction of 18% in cancer risk.</p> Graphical Abstract <p></p>