Male Reproductive Hormone Disturbance Of Exposure To Pyrethroid Pesticides And Polycyclic Aromatic Hydrocarbons

Partâ… Determination of Pyrethroids Metabolite in Human UrineTo develop a sensitive and specific method of GC-MS for the determination of 3-phenoxybenzoic acid(3-PBA)in human urine.Internal standard solution of 2-phenoxybenzoic acid(2-PBA)was added to the urine sample.After acid hydrolysis and extraction with n-hexane,the organic phase was basified with NaOH for further clean-up.The carboxylic acids were re-extracted into the aqueous phase.After acidification and extraction into n-hexane again,the metabolite was derivatized with N-tert-butyldimethylsilyl- N-methyltrifluoro acetamid(MTBSTFA)and analyzed by GC-MS in electron impact mode.The linear range for 3-PBA was 0.05-30μg/L with the correlation coefficient of 0.997.The limit of detection for 3-PBA was 0.01μg/L.The RSD of the inter-day imprecision was between 2.4 and 3.8%,intra-day imprecision was between 8.7%and 10.8%at a spiked concentration of 0.1,1.0 and 4.0μg/L and the relative recovery was between 94.3%and 120.6%.The method presented here is reliable,economic,and more sensitivity than other methods. By this procedure,we can quickly and exactly detect the urinary levels of 3-PBA,the general metabolite of pyrethroids,which presents the exposure to pyrethroids.Partâ…¡The Relationship of 3-PBA and Male Reproductive Hormones among Non-occupational Exposure MalesMany pesticides possess hormonal activities and have been classified as EDCs.Synthetic pyrethroids are one kind of the most common pesticides used in the world.In the present study,we explored the association between serum reproductive hormone levels and urinary creatinine(CR)adjusted concentration of 3-phenoxybenzoic acid(3-PBA),a general metabolite of pyrethroids,in Chinese adult men.Study subjects(n=212)were from the affiliated hospitals of Nanjing Medical University.By using GC-MS,urinary 3-PBA level of each subject was measured and adjusted by urinary CR.Blood samples were collected for measuring serum levels of reproductive hormones,including follicle stimulating hormone(FSH),luteinizing hormone(LH),estradiol(E₂), testosterone(T)and prolactin(PRL).All of subjects had detectable levels of 3-PBA in their urine samples.The median concentration of 3-PBA was 0.815μg/g·CR.The results showed that there was a positive associations between the levels of serum LH and 3-PBA(P=0.013)but negative associations between E₂ and 3-PBA level(P=0.022)and the adjusting P-value were 0.044 for LH and E₂,but no associations were found between other hormones and 3-PBA level,which suggested that pyrethroids are able to disrupt the male endocrine function.In adult men,urinary 3-PBA levels were associated with increased LH and reduced E₂ levels.On a population level,these alterations show potential public health importance because of widespread exposure to these pesticides.Partâ…¢Determination of Polycyclic Aromatic Hydrocarbons Metabolite in Human UrineTo develop a sensitive and specific method of LC-MS/MS for the determination of hydroxy- polycyclic aromatic hydrocarbons(PAHs) (1-naphthol,1-N;2-naphthol,2-N;2-hydroxyfluorene,2-F;1-hydroxypyrene, 1-P)in human urine.After enzyme hydrolysis and extraction with solid phase extraction and analyzed by LC-MS/MS in electrospray ionization(ESI)mode. The linear range for PAHs was 1-100μg/L with the correlation coefficient more than 0.99.The limit of detection for 1-P was 0.15μg/L,for the 1-N,2-N and 2-F was 0.3μg/L.The RSD of the inter-day imprecision was between 3.3%and 12.3%,intra-day imprecision was between 9.6%and 21.4%at a spiked concentration of 3,8 and 80μg/L and the relative recovery was between 80.8% and 122.7%.The method presented here is reliable and economic.By this procedure,we can quickly and exactly detect the hydroxy- PAHs,the general metabolite of PAHs,which presents the exposure to PAHs.Partâ…£The Relationship between Polycyclic Aromatic Hydrocarbon Metabolites and Male Reproductive Hormones among Non-occupational Exposure MalesMany PAHs possess hormonal activities and have been classified as EDCs. PAHs are ubiquitous environmental contaminants in the world.In the present study,we explored the association between serum reproductive hormone levels and urinary CR adjusted concentration of 1-N,2-N,2-F and 1-P,in Chinese adult men.Study subjects(n=642)were from the affiliated hospitals of Nanjing Medical University.By using LC-MS/MS,urinary 1-N,2-N,2-F and 1-P level of each subject were measured and adjusted by urinary CR.Blood samples were collected for measuring serum levels of reproductive hormones,including FSH, LH,E₂,T and PRL.All of subjects had detectable levels of four metabolites of PAHs in their urine samples.The median concentration of 1-N,2-N,2-F and 1-P were 2.440,4.176,2.843 and 1.148μg/g·CR.There were suggestive association between increased CR-adjusted 1-N tertiles and E₂ concentration, 2-F tertiles and LH,FSH level,1-P and E₂ level;whereas other hormones were weakly or non-significantly associated with other metabolites tertiles, respectively.The results also showed that there were negative associations between the levels of serum LH and 1-P(P=0.011)and the adjusting P-value was 0.048,but no associations were found between other hormones and PAHs metabolites level.These observed associations between hydroxy- PAHs levels and some altered hormone level indicated the slight reproductive effects on adult men of PAHs exposure.