Organic vs conventional agriculture: evaluation of cadmium in two of the most consumed vegetables in Brazil

Cadmium (Cd) concentrations were evaluated in conventionally and organically grown foods. The samples were prepared, submitted to acid extraction and analyzed by Graphite Furnace Atomic Absorption Spectrometry (GFAAS). The mean concentration of Cd found in organic lettuce samples was 0.0811 +/- 0.0367 mg kg(-1), while in conventional lettuce samples it was 0.1549 +/- 0.0266 mg kg(-1). Organic carrot samples had a mean concentration of Cd of 0.1064 +/- 0.0553 mg kg(-1), while samples of carrots cultivated by the conventional method had a mean concentration of 0.1174 +/- 0.0780 mg kg(-1). It was observed that conventionally cultivated foods in individual evaluations presented concentrations of 1.2 to 3.1 times higher of Cd when compared to organic vegetables. The Brazilian legislation regarding the detection of Cd is established by RDC n degrees 42. It can be inferred that the average concentrations found in this study are within the values established by the legislation. When considering Cd exposure through vegetable consumption by evaluating the estimated daily metal intake (EDI) and the target hazard quotients (THQ), the samples did not present a potential health risk.