The Distribution Of Arsenic And Immersion Washing Effect On Arsenic Residues In Rice In Heilongjiang Provinces

The paper analyzes 50 regions of 50 rice samples collected from Heilongjiang.The sampling area selected is based on the "national food security and long-term planning framework(2008-2020)" and the provincial government of Heilongjiang province "billions of pounds of grain production capacity construction plan".In this paper,the residual amount of total arsenic and inorganic arsenic in rice was determined,and the effects of soil and irrigation water on the residual arsenic in rice were analyzed.The specific research contents are as follows:(1)The total arsenic content in paddy,brown rice and polished rice samples ranges from 0.214 to 0.47 mg/kg,0.096 to 0.216 mg/kg,and 0.021 to 0.078 mg/kg.The content of inorganic arsenic in paddy,brown rice and polished rice samples ranges from 0.198 to 0.439 mg/kg,0.076 to 0.196 mg/kg,and 0.017 to 0.064 mg/kg.The total arsenic content of all paddy,brown rice and polished rice samples was 0.352 mg/kg,0.128 mg/kg,0.040 mg/kg.The average content of inorganic arsenic in all rice,brown rice and rice samples was 0.327 mg/kg,0.112 mg/kg,0.032 mg/kg.The residual amount of total arsenic and inorganic arsenic in brown rice was 35.5%and 34.2%,respectively,and the residual amount of total arsenic and inorganic arsenic in polished rice was 31.2%and 28.6%from brown rice.The concentrations of arsenic is decreasing in the progress of the paddy from brown rice into polished rice,The relationship between arsenic content in different parts of grain of rice husk>brown rice>polished rice.(2)According to the pollution degree of arsenic in paddy in different areas,the total arsenic residues of soil and irrigation water in the rice growing environment were detected respectively.The results showed that the total arsenic content in irrigation water was 0.336-0.702g/L,and in soil was 0.811-0.952mg/kg.The results show that the total arsenic content in paddy rice has a certain relationship with the soil and irrigation water,that is,the higher the total arsenic content,the higher the content of total arsenic in soil and irrigation water.Indicating that the environmental pollution led to the migration of arsenic absorbed by the roots of rice,which led to a large amount of total arsenic in rice.With the deterioration of environmental pollution,soil and irrigation in the natural background of arsenic increased,the arsenic content of rice must rise,so we must control environmental pollution.(3)Rice panning experiment showed that the residual amount of total arsenic in the first and second rice panning was 62.8-70.5%and 48.4-58.9%respectively.The residual amount of inorganic arsenic in the first and second rice panning was 65.0-74.4%and 60.3-68.1%.It indicates that the arsenic residue in rice decreases with the increase in the number of panning.The residual amount of arsenic in the soaking experiment was 67.4%-94.8%and 90.5%-98.2%respectively after 0.5 hours of soaking.After 1 hour,the total arsenic and inorganic arsenic residues were 64.0%-94.9%And 85.3%-95.1%,respectively.After 2 hours,the total arsenic and inorganic arsenic residues were 60.0%-92.6%and 80.0%-92.0%respectively.After 3 hours,the total arsenic and inorganic arsenic residues were 56.0%-89.8%The total arsenic residues were 53.1%-86.6%and 69.5%-84.7%after 4 hours.The total arsenic residues were 49.7%-83.8%and 63.2%-80.4%after 5 hours.With longer time immersion for rice,the lower content of total arsenic and inorganic arsenic in rice,indicating that some heavy metals transfer to the soak liquid.