Abstract:

In this study, 108 groups of rice grain and soil samples from Hunan province were collected for analysis
of Cd content in rice grain, and the contents of total and available Cd and available Zn in soil by inductively coupled
plasma mass spectrometry (ICP-MS). The results showed that the Cd contents in rice grain were in the range of 0.015–
1.05 mg/kg, with an average of 0.272 mg/kg, and over 70% of the rice samples were in the range of 0.10–0.30 mg/kg. The ranges
of total and available Cd, and available Zn in soil were 0.180–1.89, 0.116–0.742, and 0.893–17.37 mg/kg, with average values of
0.679, 0.295, and 5.02 mg/kg, respectively. The statistical analysis by SPSS software showed that the content of Cd in rice grain
showed an upward opening quadratic curve relationship with the content of total Cd in soil and presented a downward opening
quadratic curve relationship with the content of available Zn in soil (P = 0.000). However, it was positively correlated with the
content of available Cd in soil (P = 0.000). The results showed that Cd content in rice grainwas increased by the available Cd
content in soil, but high concentrations of available Zn in soil restricted accumulation of Cd in rice grain.

Key words: rice grain, soil, cadmium, zinc