Effects Of Metal Cations On The Accumulation Of Metal Pollutants In Leafy Vegetables

Leafy vegetables,as important consumer goods in the dining table of residents,are easy to enrich heavy metal pollutants and have high safety hidden dangers-In order to reduce the risk of heavy metal pollution of leafy vegetables and improve the safety level of leafy vegetables,Escort the public for food safety.In this paper,Shanghai cabbage was taken as the research object to explore the ways to reduce the accumulation of heavy metal pollutants in leafy vegetables.As a convenient and effective culture mode,hydroponic culture model can reduce the interference factors in the environment and ensure the content and proportion of metal cations in the research process.Orthogonal experimental design is an efficient,rapid and economical multi-factor experimental design method,which can achieve the same results as a large number of comprehensive tests with the least number of tests.Therefore,the effects of three different metal cations,K+?Ca2+?Mg2+,on the accumulation of lead,cadmium,mercury and arsenic in Shanghai cabbage were studied by orthogonal experiment and hydroponic model.And get as follows the conclusion is as follows:(1)Different metal cations in the culture medium had certain effects on the accumulation of lead,cadmium,mercury and arsenic in Shanghai cabbage,and the effects of different cations on the accumulation of different metal pollutants were different.The effect of potassium ion concentration on the accumulation of arsenic in Shanghai green was significant,but the effect on the accumulation of lead,cadmium and mercury was not significant.The effect of calcium ion concentration on the accumulation of lead and arsenic was significant,but not on the accumulation of cadmium and mercury,but the effect of magnesium ion concentration on the accumulation of cadmium was significant,but on the accumulation of lead,arsenic and mercury was not significant.Shanghai cabbage With the increase of calcium concentration,the accumulation of lead and arsenic increased at first and then decreased,while the contents of cadmium and mercury decreased at first and then increased.With the increase of potassium concentration,the accumulation of lead increased at first and then stabilized,the accumulation value of cadmium continued to decrease,and the accumulation of mercury and arsenic increased at first and then decreased.With the increase of magnesium ion concentration,the accumulation of lead and arsenic decreased at first and then increased,the absorption of cadmium decreased continuously,and the content of mercury increased continuously.(2)The accumulation of different metal pollutants is also affected by different metal cations.The cationic order affecting lead absorption in Shanghai cabbage was Ca2+>K+>Mg2+,the cationic order affecting cadmium absorption in Shanghai cabbage was Mg2+>Ca2+>K+,and the cationic order affecting mercury absorption in Shanghai cabbage was Ca2+>K+>Mg2+.The cationic order affecting arsenic absorption in Shanghai cabbage wasK+>Mg2+>Ca2+.(3)By calculating the comprehensive pollution index of different factors and different levels,the comprehensive pollution degree of K+?Mg2+?Ca2+metal cations at different levels can be determined under this experimental system,in which 2.5mmol/L potassium ion,10mmol/L calcium ion,2mmol/L magnesium ion comprehensive pollution degree is the lowest.