Distribution Of Aluminum Species In Atmospheric Particulates And Health Risk Assessment

The toxic effects of aluminum on organisms and the environment have gradually become popular.The toxicity of different forms of aluminum to organisms varies greatly,and the form of aluminum in the environment is very complex.The morphological division and analysis of aluminum in environmental samples is of important practical significance for studying its bioavailability and toxicological properties.We further determined the total aluminum in the sample by simultaneous sampling of PM_2.5.5 and PM₁₀0 in the atmosphere.The morphology of aluminum in samples was extracted by chemical extraction and the distribution characteristics of aluminum in PM_2.5.5 and PM₁₀0 were discussed and the health risks of aluminum exposure were evaluated.The main conclusions are as follows:?1?The PM_2.5.5 and PM₁₀0 at the sampling point in spring and winter are generally higher than those in summer and autumn,indicating that air pollution is more severe in spring and winter than in summer and autumn.The spring-autumn climate at the sampling point is relatively stable,but there is rainfall before and after the summer sampling period,which has a greater impact on particulate matter erosion.In Nanchang,during the winter sampling period,the wind speed is relatively large,which is affected by the cold air and shows irregular changes in the concentration of particulate matter.?2?There is a significant linear relationship between the collected samples PM_2.5and PM₁₀,and the regression equation is:PM₁₀=1.236PM_2.5+35.547,the correlation coefficient reached 0.912.The PM_2.5/PM₁₀0 value accounted for about 61%,indicating that the proportion of fine particles in the PM₁₀0 near the sampling point is greater;?3?The average concentration of total aluminum in PM_2.5.5 was 219.95 ng/m³?spring?,192.68 ng/m³?summer?,188.53 ng/m³?fall?,and 245.11 ng/m³?winter?.The average concentration of total aluminum in PM₁₀0 was 245.89 ng/m³?spring?,215.91ng/m³?summer?,234.81 ng/m³?fall?,and 301.52 ng/m³?winter?.The total aluminum concentration in PM_2.5.5 and PM₁₀0 showed the trends of winter>spring>summer>autumn,which was basically consistent with the seasonal distribution of PM_2.5.5 and PM₁₀0 mass concentrations,indicating that the distribution of aluminum in the atmosphere was related to the concentration of particles.The correlation between mass concentration of PM_2.5.5 and total aluminum is better;?4?The concentration of Al³⁺aluminum in the PM_2.5.5 sample ranged from 5.40 to29.34 ng/m³.The concentration range of hydroxy aluminum is 1.04⁸.23 ng/m³.The aluminum concentration range of Al?OH?₃⁰ is 29.84⁹5.12ng/m³.Al-HA morphology aluminum concentration range is 1.56¹6.24ng/m³.The aluminum concentration of Al³⁺in the PM₁₀0 sample ranged from 10.87 to 50.93 ng/m³,and the range of the hydroxy aluminum concentration ranged from 2.64 to 8.94 ng/m³.The aluminum concentration range of Al?OH?₃⁰ is 54.42¹49.63ng/m³,and the concentration of Al-HA is 1.60¹9.37ng/m³.In the samples of PM_2.5.5 and PM₁₀,the distribution of four aluminumspecieswascolloidAl?OH?₃⁰>Al³⁺>Al-HA>hydroxylaluminum.Compared with the distribution characteristics of aluminum in the soil,it indicates that the source of aluminum in the atmosphere is more complicated;?5?The diurnal variation of Al³⁺and hydroxy aluminum is the largest.The Al-HA form aluminum changes the smallest.The stability of Al³⁺and hydroxy-aluminum in the particles is poor and susceptibility to morphological changes.Al-HA is the most stable form of aluminum.The distribution characteristics of different forms of aluminum in coarse and fine particles are also different:The Al³⁺form of aluminum has a great difference between PM₁₀0 and PM_2.5,but there is little difference in the distribution of hydroxy aluminum between PM_2.5.5 and PM₁₀.The colloidal Al?OH?₃⁰ and Al-HA morphologies of aluminum peaks and troughs appear alternately in PM_2.5.There is a morphological transformation between colloidal aluminum and Al-HA in PM_2.5.The colloidal Al?OH?₃⁰ and Al³⁺peaks and troughs alternate in PM₁₀,indicating that there is a morphological transformation between colloidal aluminum and Al³⁺in PM₁₀.Precipitation occurs at all of these feature points.Precipitation has an effect on the form of aluminum in atmospheric particulates and can cause inter-conversion between different forms.?6?Al³⁺aluminum has a higher percentage of PM₁₀,while other forms of aluminum account for a higher proportion of PM_2.5,and toxic forms of aluminum in PM_2.5.5 account for 0.21 of the total extraction.The toxic morphous aluminum in PM₁₀accounted for 0.28 in the total extraction form,and PM₁₀0 toxic aluminum form was enriched to a higher degree;?7?The Al³⁺form of aluminum in PM_2.5.5 showed the trend of winter>spring>summer haze,the monohydroxyaluminum and Al?OH?₃⁰ states showed the trend of winter>spring>summer>autumn,and the morphology of Al-HA was winter>autumn>spring>summer trend;The Al³⁺form of aluminum in PM₁₀0 showed a winter>spring>autumn>summer trend,while the mono-hydroxy form aluminum was the highest in winter,there is no obvious difference in other seasons.The trend of Al?OH?₃⁰ was winter>spring>autumn>summer,Al-HA was winter>spring>autumn>summer;?8?Assessment of the health risk of aluminum in fine particulate matter(PM_2.5),.Calculate the daily average total aluminum exposure in PM_2.5.5 to be 5.56×10⁷ng/m³.The daily average exposure of toxic aluminum is 4.71×10⁶ng/m³.Aluminum chronic non-carcinogenic health risk factor HQ=0.011.The chronic non-carcinogenic health risks of aluminum in the atmosphere are low.