Contamination status, risk assessment, and control measures of heavy metals in tuber crops

Abstract

Tuber crops (TCs) are an important food source for people; however, the contamination of TCs by heavy metals (HMs) has not received sufficient attention. In this study, 253 batches of TCs samples containing HMs (Pb, Cd, Cr, Hg, As) were collected to investigate the contamination status and health risks. The results showed that different TCs contained different concentrations of HMs, while cassava exhibited the highest levels of each HM. In terms of health risks, the non-carcinogenic and carcinogenic risks associated with TCs consumption were in the “Negligible risk”, “Cautionary risk”, respectively. On the economic and age scales, the health risk concerning TCs consumption varied. The health risks increased when cassava was included in the diet. Field experiments were conducted to explore the factors influencing the accumulation of HMs and propose measures to control HMs contamination. When measures were taken to intervene in the factors (soil HMs, soil organic matter, soil pH and cassava variety) affecting the HMs content in cassava, the health risks were significantly reduced, with a maximum reduction of 43.71% and 17.50% in non-carcinogenic and carcinogenic risks, respectively. This study provides ideas for the pollution management of HMs in TCs.