Micronutrients and heavy metals in rice farms: the case of Ahvaz and Bawie Counties, Khuzestan Province, Iran

Environ Monit Assess. 2022 Dec 5;195(1):173. doi: 10.1007/s10661-022-10774-6.

Abstract

This study addressed micronutrients (Fe, Zn, Cu, Mn, Co) and heavy metals (As, Pb) in the soil and rice crop in Khuzestan Province, Iran. Twenty-eight composite soil and grain samples from the intended rice farms were garnered during harvest time. Concentrations of the elements in the samples and in the grains were, respectively, determined by inductively coupled plasma optical emission spectrometry and inductively coupled plasma mass spectrometry device. The average concentration of As, Fe, Co, Cu, Mn, Pb, and Zn in soil of crop were 2.71, 20,065.8, 10.43, 22.28, 422.28, 5.85, and 47.07 mg/kg, respectively. The physicochemical properties of soil, bioconcentration factor, daily intakes, and health risk assessment of the elements were calculated. The results revealed that the area covered by alkaline saline soils is poor in micronutrients. Bioconcentration factor values of all elements were less than 1. Low levels of bioconcentration factor may be for low levels of nutrients in the soil and physicochemical conditions of the soil. Furthermore, the daily intake of Co (adults' group) and Fe and Zn (children group) was very low. Health risk assessment showed only adults are threatened by non-cancerous diseases due to excessive value of all the elements (HI = 2.53) and cancerous diseases caused by excessive As and Pb (2.86E-04 and 2.01E-05, respectively). Considering that Khuzestan Province is the fourth largest producer of rice in Iran, the lack of micronutrients and the presence of heavy metals in rice produced in the study area can adversely affect consumers. Further investigation is therefore a must in the region.

Keywords: Health risk; Heavy metals; ICP-MS; ICP-OES; Micronutrients; Rice.

MeSH terms

  • Adult
  • Child
  • Environmental Monitoring
  • Farms
  • Humans
  • Iran
  • Lead / analysis
  • Metals, Heavy* / analysis
  • Micronutrients / analysis
  • Oryza* / chemistry
  • Risk Assessment
  • Soil / chemistry
  • Soil Pollutants* / analysis

Substances

  • Soil Pollutants
  • Micronutrients
  • Lead
  • Metals, Heavy
  • Soil