Occurrence and risk assessment of pesticide residues, heavy metals, and mycotoxins in green and roasted coffee beans distributed in the Republic of Korea

Coffee is one of the most widely consumed beverages globally, raising concerns regarding chronic dietary exposure to chemical contaminants. This study provides a comprehensive and simultaneous assessment of pesticide residues, mycotoxins, and heavy metals in coffee products distributed in the Republic of Korea, along with an evaluation of potential health risks. In 2025, a total of 88 samples (green coffee beans, n = 45; roasted coffee beans, n = 43) were collected from online markets, supermarkets, and local coffee shops in Busan. A multi-residue analytical approach targeting 480 pesticides was employed using GC–MS/MS and LC–MS/MS, while mycotoxins were determined by LC–MS/MS and heavy metals were quantified by ICP–MS and a direct mercury analyser. Pesticide residues were detected in 14 samples (15.9%), exclusively in green coffee beans, whereas no residues were detected in roasted coffee. Mycotoxins were identified at trace levels in a limited number of green coffee samples but were absent in roasted products. Pb and Cd were frequently detected, with Cd concentrations significantly higher in roasted coffee beans (p < 0.001), likely due to concentration effects during roasting. Mean total As concentrations were comparable to those of Cd, whereas Hg concentrations were substantially lower than those of the other heavy metals and showed no significant differences between sample types. Dietary exposure was estimated using a screening-level approach (ND = 0). Under a conservative worst-case scenario assuming that 100% of total arsenic was present as inorganic arsenic, the margin of exposure (MOE) was approximately 56. Despite this, exposure levels for all analytes remained substantially below relevant health-based guidance values. Principal component analysis revealed no distinct clustering by origin or processing stage, indicating that contamination patterns are influenced by multiple factors. Overall, these findings demonstrate that coffee distributed in Korea is unlikely to pose significant health risks under typical consumption conditions.