Analysis Of Influencing Factors On The Mecury Levels In Hair And Nails Of The General Population

With the rapid development of economy,the global mercury emissions continue to increase.Hg in environments exercises a great influence on the accumulation of mercury in general population and human health.Past research of mercury accumulation mainly focused on occupational mercury exposure group through multiple channels,the number of systematic studies for mecury levels in hair and nails of the general population and affecting factors was very low.This study selected the 11 provinces.On the basis of questionnaire survey we collected 1563 general population samples(including 941 hair samples,622 nails samples).By measuring the sample mercury levels,we carried on risk assessments and correlation analysis of mecury levels in hair and nails of different gender,ages,regions and living habits.The aims of this research was to know the mercury accumulation levels of general population,to discuss the influence factors of the mercury accumulation,to provide basic data for positive prevention and preventive measures.The main results of the research were as follows:1.Average mercury levels in hair and nails were 0.260±0.158 mg/kg and 0.113±0.045 mg/kg,respectively.Compared to the mercury levels of hair in early years,the mercury levels of hair decreased;Compared with the results of other cities at home and abroad,mercury level in hair of this research was in the middle and low level.The determination of mercury level of nails in some cities at home and abroad was close to the investigation.2.Mercury levels correlation analysis between groups of hair and nails sample indicates that mercury levels of hair and nails were highly significant positive correlation(r = 0.602,P < 0.01);The average statistical test results also showed that the hair mercury levels were significantly higher than nails mercury levels(P < 0.01),the mercury content of hair was about 2 times of nails mercury levels,which showed that mercury was more likely to accumulate in hair.Hair and nails can be used to monitor the mercury exposure for general population,and hair monitoring was sensitivity than nails3.According to the USEPA daily toxic exposure dose(RfD),this research adopted single factor index method to calculate mercury quality index(Pi).The results of assessment of mercury exposure risk indicated that the number of mercury levels of hair samples above the health level accounted for 0.53% of the total samples,Pi value of coastal residents was obviously higher than inland areas.4.The average mercury contents of hair in men and women were 0.233±0.130 mg/kg and 0.284±0.175 mg/kg,respectively.The average mercury contents of nails were 0.101 ± 0.032 mg/kg and 0.124±0.049 mg/kg,respectively.Both mercury levels in hair and nails are women slightly higher than the male,but statistical test results showed that there is no significant difference in gender of any samples(P > 0.05).5.The distribution of mercury contents in hair and nails changing along with the ages showed that,the mercury levels in hair and nails were higher in 20~40 years old people than that in younger and older people.Before 15 years old,mercury contents was low and basically stable.The highest mercury levels were between 20 and 40 years old,and after that mercury levels of hair and nails declined slowly with ages.20 to 40 age group mercury exposure at risk was most due to living habits.6.The average mercury contents in hair of coastal and inland population were 0.302 mg/kg and 0.205 mg/kg,while average mercury contents in nails were 0.140 mg/kg and 0.078 mg/kg.The variance analysis results indicated that the coastal mercury levels in both hair and nails were significantly higher than the inland(P < 0.001).The coastal is about 1.5~ 2 times of the inland.7.Influence factors of different living habits analysis results showed that the use frequency of whitening cosmetics and mercury content in hair had an obvious correlation(r = 0.142,P < 0.05),while there was no significant difference between the use of whitening cosmetics and nails mercury levels.At the same time,the accumulation of mercury in hair and nails increased with the increase frequency of the use of fish consumption and dyeing(P < 0.05).It indicated that different living habits such as using whitening cosmetics,eating fish and dyeing can lead to the accumulation of mercury in human body.To sum up,although the average mercury levels of hair and nails in survey area was lower than the past,the living habits such as using whitening cosmetics,eating fish and dyeing still exacerbated mercury exposure risk.It is suggested that we should be careful with whitening cosmetics containing mercury,eat less aquatic products polluted by mercury,reduce the frequency of dyeing.The emissions and levels of mercury in different environment were important sources of mercury accumulation in human hair and nails,especially water,air and soil environment.Despite the influence of the living habits,measures should be taken to reduce environmental mercury emissions,which was the main factors to reduce the mercury exposure risk and of the general population.