Depending on the harvest conditions, coffee beans can be contaminated by soil when dropped to the ground. It is well known
that agricultural soils act as sinks for agrochemicals applied to the crops. While coffee is brewed, substances present in
the roasted and ground coffee beans are extracted by hot water, emphasizing the need to assess the possible transfer of impurities
from the soil to the beverage. Soil-contaminated samples of roasted coffee beans were split into 2 groups according to the
treatments: (a) washed and ground and (b) only ground. Brewing was performed in a household espresso machine for both coffees.
The resulting beverage was freeze-dried and the elemental composition determined by instrumental neutron activation analysis
(INAA). The mass fractions of the terrigenous elements Fe, La, Sc, Sm and Th in the freeze-dried non-washed coffee beverages
were, at least, 2 times higher than in the washed samples. These elements are tracers of the soil, indicating that the impurities
from the soil reached the beverage.