Comparison And Evaluation Of Eye UV Exposure Of Caucasus,Mongolia And Negroids At Different Latitudes

Objective: To explore the differences of eye UV exposure in the three species of Caucasus,Mongolia and Negroid at different latitudes,and evaluate the risk of uv exposure in different latitudes.To investigate the relationship between UV exposure and cataract incidence in different countries.Methods: Using the UV exposure function model established by our research team,we calculated the UV exposure of the eyes of the Caucasians,Mongolians and Negroid in their respective representative cities at corresponding evaluation time,make comparisons between latitude,season and race.The calculated amount of UV exposure to the eye was compared with age-standardized cataract prevalence in each country to explore the relationship between the two.Results: 1.In the area within the tropic of Cancer(23.26°),the UV exposure intensity in the UVA band was higher in the cool season than in the hot season,and there was no difference in the UVB band throughout the year.At the boundary of middle and low latitudes(30°),the UVA band of eye UV exposure intensity was higher in spring and autumn than in summer,summer than in winter,and the UVB band was higher in spring than in winter.There was no difference between summer and autumn.In the middle and high latitudes(47°～64°),the UVA and UVB bands of eye UV exposure intensity were higher in summer than in spring and autumn,and higher in winter.2.When the sun is directly directed at the equator,the intensity of eye UV exposure in the Southern hemisphere increases gradually with the increase of latitude(<33.55°),while the intensity of eye UV exposure in the northern hemisphere decreases gradually with the increase of latitude(34.4°～64.13°).When the sun is directly on the tropic of Capricorns,there is no difference in the UV exposure intensity of the southern eye with the increase of latitude(4.25°～33.55°),while the UV exposure intensity of the northern eye decreases gradually with the increase of latitude(18.25°～47.90°).When the sun is directly on the Tropic of Cancer,the eye UV exposure intensity in the southern hemisphere decreases gradually with the increase of latitude(4.25°～33.55°),while the eye UV exposure intensity in the northern hemisphere decreases gradually with the increase of latitude(48.87°～64.13°).3.The intensity of UV exposure in the eyes of three species was the highest in Negroid race and the lowest in Caucasian race.4.The daytime risk exposure time of the three species of Caucasians,Mongolians and Negroes decreased gradually with the increase of the latitude of their cities.The daytime risk exposure time of the three species of females was the longest and that of the Caucasians the shortest.The daytime risk exposure time of the three species of females was higher than that of males,and the average time was 1.5 times that of males.5.The UVB band of UV exposure was positively correlated with cataract prevalence in various countries.Conclusion: 1.The annual UV exposure in low latitudes is higher than that in high latitudes.2.The risk of UV exposure to the eye was highest among Negroid,lowest among Caucasians,and higher among women than men.3.There was a positive correlation between UVB exposure and cataract incidence.4.The duration of daytime risk exposure was the longest for Negroid women and the shortest for Caucasian men,with females averaging 1.5 times as long as males.