Concentrations of selective metabolites of organophosphorus pesticides in the United States population

We report population-based concentrations (stratified by age, sex, and composite race/ethnicity variables) of selective metabolites of chlorpyrifos (3,5,6-trichloro-2-pyridinol; TCPY), chlorpyrifos methyl (TCPY), malathion (malathion dicarboxylic acid; MDA), diazinon (2-isopropyl-4-methyl-6-hydroxypyrimidine; IMPY), methyl parathion (para-nitrophenol; PNP), and parathion (PNP). We measured the concentrations of TCPY, MDA, IMPY, and PNP in 1997 urine samples from participants, aged 6-59 years, of the National Health and Nutrition Examination Survey, 1999-2000. We detected TCPY in more than 96% of the samples tested. Other organophosphorus pesticide metabolites were detected less frequently: MDA, 52%; IMPY, 29%; and PNP, 22%. The geometric means for TCPY were 1.77 microg/L and 1.58 microg/g creatinine. The 95th percentiles for TCPY were 9.9 microg/L and 8.42 microg/g creatinine. The 95th percentiles for MDA were 1.6 microg/L and 1.8 microg/g creatinine. The 95th percentiles for IMPY and PNP were 3.7 microg/L (3.4 microg/g creatinine) and 5.0 microg/L (4.2 microg/g creatinine), respectively. Multivariate analyses showed that children aged 6-11 years had significantly higher concentrations of TCPY than adults and adolescents. Similarly, adolescents had significantly higher TCPY concentrations than adults. Although the concentrations between sexes and among composite racial/ethnic groups varied, no significant differences were observed.     

Measurement of dialkyl phosphate metabolites of organophosphorus pesticides in human urine using lyophilization with gas chromatography-tandem mass spectrometry and isotope dilution quantification

Urinary dialkylphosphate (DAP) metabolites have been used to estimate human exposure to organophosphorus pesticides. We developed a method for quantifying the six DAP urinary metabolites of at least 28 organophosphorus pesticides using lyophilization and chemical derivatization followed by analysis using isotope-dilution gas chromatography-tandem mass spectrometry (GC-MS/MS). Urine samples were spiked with stable isotope analogues of the DAPs and the water was removed from the samples using a lyophilizer. The dried residue was dissolved in acetonitrile and diethyl ether, and the DAPs were chemically derivatized to their respective chloropropyl phosphate esters. The chloropropyl phosphate esters were concentrated, and analyzed using GC-MS/MS. The limits of detection of the method were in the low microg/l (parts per billion) to mid pg/ml range (parts per trillion) with coefficients of variation of 7-14%. The use of stable isotope analogues as internal standards for each of these metabolites allows for sample-specific adjustment for recovery and thus permits a high degree of accuracy and precision. Use of this method with approximately 1100 urine samples collected from pregnant women and children indicate that the low limits of detection allow this method to be used in general population studies.     

Assessment of the exposure of pest control operators to organophosphorus pesticides. Organophosphorus pesticides in blood and alkyl phosphate metabolites in urine

Pest control operators usually spray pesticides in small areas such as a kitchen in a restaurant and are exposed to various pesticides, especially those of the organophosphorus (OP) type. In order to evaluate their occupational exposure to OP pesticides during the work, OP pesticides in blood and alkyl phosphate metabolites in urine of these operators were analyzed and the relationship between pesticide exposure and analytical results were studied. OP pesticides in blood were analyzed by gas chromatography with flame photometric detector (FPD-GC) after separation of phospholipid in blood with silicagel column chromatography. OP pesticides were not detected in any blood samples (the limit of detection was 1 ng/ml). Dimethylphosphate (DMP) and dimethylthiophosphate (DMTP), being urinary metabolites of OP pesticides, were analyzed by FPD-GC after benzyl derivatization. This method eliminated interfering peaks in gas chromatograms. The ratio of two isomeric derivatives of DMTP was found to be constant. Both DMP and DMTP of the exposed group were significantly higher than those of the non-exposed group, DMP being higher than DMTP. The ratio of DMP to DMTP in the fenitrothion-dichlorvos-exposed group was significantly higher than that in the fenitrothion-exposed group. It was considered that the ratio might reflect a result of pesticide exposure. The urinary metabolites of OP pesticides tended to become lower with the lapse of time since the last exposure. However, small amounts were detected in a few samples even 5 days after the last exposure.     

Dialkyl phosphate metabolites of organophosphorus in applicators of agricultural pesticides in Majes – Arequipa (Peru)

Background  

Organophosphorus (OPs) pesticides are the most commonly used pesticides in Peruvian agriculture. The population at risk for OPs exposure includes formulators, applicators and farmers. Majes Valley is the most important agricultural center of the Southern region of Peru. The present study was aimed to determine the knowledge about using OPs, safety practice and urinary dialkylphosphate metabolites on OP applicators in the Majes Valley, Peru.     

有机磷农药代谢产物分析的研究进展

长期低剂量接触有机磷农药(organophosphorus pesticides,OPs)可引起迟发性神经疾病,严重时有诱发突变和致癌作用.根据OPs的化学和毒理学性质,可以通过生物监测方法评价人体接触OPs的程度及其对健康可能产生的潜在影响.     

气相色谱法分析尿样中六种有机磷农药代谢产物

目的：本文采用气相色谱法进行人尿样中6种二烷基磷酸酯类代谢物（DMP、DEP、DMTP、DETP、DMDTP、DEDTP）定量分析。方法：将尿样与乙腈混溶、蒸发，以二丁基磷酸酯（DBP）作为内标，用五氟溴苄苯（PFB）作为衍生试剂，50℃下衍生反应16h，用气相色谱法／火焰光度检测器进行分析。结果：代谢物浓度在100μg/L时，6种化合物的回收率均大于66％，最低检出限范围为2μg/L-15μg/L。结论：结果表明，该方法可用于监测职业人群对有机磷农药的接触水平。     

Fracture risk in the U.S. Medicare population

Using data from the 5% U.S. Medicare sample, we estimated the actuarial (life table) risk that a person aged 65 will fracture the upper or lower limbs or the pelvis, by age 75, 80, 85, and 90, taking into account the chance of dying in the interval. The actuarial risk of a 65-year old white woman sustaining a fracture by age 90 is 16% for the hip, 9% for distal forearm, 5% for proximal humerus, and 4% for ankle. Black women and white men have substantially lower risks, and the risks for black men are very low. Although hip fractures pose the single greatest risk, the risk of all other fractures combined is greater. White women have particularly high risks for all fractures, because of their longevity as well as their high fracture rates. It is important to adjust for the probability of dying when estimating risks in an elderly population.     

Concentrations of urinary phthalate metabolites are associated with increased waist circumference and insulin resistance in adult U.S. males

BACKGROUND: Phthalates impair rodent testicular function and have been associated with anti-androgenic effects in humans, including decreased testosterone levels. Low testosterone in adult human males has been associated with increased prevalence of obesity, insulin resistance, and diabetes. OBJECTIVES: Our objective in this study was to investigate phthalate exposure and its associations with abdominal obesity and insulin resistance. METHODS: Subjects were adult U.S. male participants in the National Health and Nutrition Examination Survey (NHANES) 1999-2002. We modeled six phthalate metabolites with prevalent exposure and known or suspected antiandrogenic activity as predictors of waist circumference and log-transformed homeostatic model assessment (HOMA; a measure of insulin resistance) using multiple linear regression, adjusted for age, race/ethnicity, fat and total calorie consumption, physical activity level, serum cotinine, and urine creatinine (model 1); and adjusted for model 1 covariates plus measures of renal and hepatic function (model 2). Metabolites were mono-butyl phthalates (MBP), mono-ethyl phthalate (MEP), mono-(2-ethyl)-hexyl phthalate (MEHP), mono-benzyl phthalate (MBzP), mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), and mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP). RESULTS: In model 1, four metabolites were associated with increased waist circumference (MBzP, MEHHP, MEOHP, and MEP; p-values 相似文献   

Rice Consumption and Urinary Arsenic Concentrations in U.S. Children

Background: In adult populations, emerging evidence indicates that humans are exposed to arsenic by ingestion of contaminated foods such as rice, grains, and juice; yet little is known about arsenic exposure among children.Objectives: Our goal was to determine whether rice consumption contributes to arsenic exposure in U.S. children.Methods: We used data from the nationally representative National Health and Nutrition Examination Survey (NHANES) to examine the relationship between rice consumption (measured in 0.25 cups of cooked rice per day) over a 24-hr period and subsequent urinary arsenic concentration among the 2,323 children (6–17 years of age) who participated in NHANES from 2003 to 2008. We examined total urinary arsenic (excluding arsenobetaine and arsenocholine) and dimethylarsinic acid (DMA) concentrations overall and by age group: 6–11 years and 12–17 years.Results: The median [interquartile range (IQR)] total urinary arsenic concentration among children who reported consuming rice was 8.9 μg/L (IQR: 5.3–15.6) compared with 5.5 μg/L (IQR: 3.1–8.4) among those who did not consume rice. After adjusting for potentially confounding factors, and restricting the study to participants who did not consume seafood in the preceding 24 hr, total urinary arsenic concentration increased 14.2% (95% confidence interval: 11.3, 17.1%) with each 0.25 cup increase in cooked rice consumption.Conclusions: Our study suggests that rice consumption is a potential source of arsenic exposure in U.S. children.     

Multiple skin cancer risk behaviors in the U.S. population

BACKGROUND: The incidence of all types of skin cancer has increased over the past 3 decades in the United States. Increased skin cancer risk is associated with exposure to ultraviolet radiation. This study examined the age-stratified prevalence and correlates of multiple skin cancer risk behaviors (infrequent use of sun-protective clothing, staying in the sun when outside on a sunny day, infrequent use of sunscreen, indoor tanning, and receiving a sunburn) among U.S. adults. METHODS: 28,235 adults participating in the 2005 National Health Interview Survey (NHIS) answered questions regarding sun-protection behaviors, indoor tanning in the past year, and sunburns in the past year. Examined correlates included geographic location, demographics, healthcare access, BMI, physical activity, smoking, alcohol use, melanoma family history, perceived cancer risk, skin sensitivity to the sun, and receipt of a total skin exam. RESULTS: The most commonly reported skin cancer risk behaviors were infrequent use of sun-protective clothing and infrequent use of sunscreen. The majority of individuals reported multiple skin cancer risk behaviors. Although significant correlates varied according to age, individuals reporting more risk behaviors were more likely younger, residing in the Midwest, male, non-Hispanic white, less-educated, smokers, risky drinkers, and had skin that was less sun-sensitive. CONCLUSIONS: The majority of the U.S. population engage in multiple skin cancer risk behaviors. A comprehensive approach to skin cancer prevention requires attention to multiple skin cancer risk behaviors that are common in the U.S. population.     

液相色谱串联质谱法定量检测尿中有机磷农药代谢物

目的建立了液相色谱串联质谱(LC-MS/MS)法测定尿中二乙基磷酸酯、二硫代磷酸二甲酯、二硫代磷酸二乙酯、4-硝基酚、3-氯-4-甲基-7-羟基香豆素和TCPY 6种有机磷农药代谢物含量的方法。方法尿样中加入酶解液,37℃水浴4h后经oasis HLB柱固相萃取,用甲醇洗脱后离心浓缩,乙腈定容;以乙酸铵做缓冲溶液,乙腈和水为流动相等梯度洗脱,经Waters Symmetry C185μm(2.1mm×150mmcolumn)分离,经在线电喷雾离子源(ESI)负离子化后,采用多反应离子监测方式(MRM)选择离子对测定。结果目标化合物的线性范围为0～1000ng/ml,6种化合物的相关系数有5种大于0.990,加标回收率在79%～130%之间,RSD<8.2%;日内、日间相对标准偏差小于15%(n=6)。结论该方法样品采集简单,特异性强,能准确、高效地检测尿样中有机磷农药代谢物。     

Non-occupational exposures to pesticides for residents of two U.S. cities

The Non-Occupational Pesticide Exposure Study, funded by the U.S. Environmental Protection Agency, was designed to assess total human exposures to 32 pesticides and pesticide degradation products in the non-occupational environment; however, the study focused primarily on inhalation exposures. Two sites—Jacksonville, Florida (USA) and Springfield/Chicopee, Massachusetts (USA)—were studied during three seasons: Summer 1986 (Jacksonville only), Spring 1987, and Winter 1988. Probability samples of 49 to 72 persons participated in individual site/seasons. The primary environmental monitoring consisted of 24-hr indoor, personal, and outdoor air samples analyzed by gas chromtography/mass spectrometry and gas chromatography/electron capture detection. Indoor and personal air concentrations tended to be higher in Jacksonville than in Springfield/Chicopee. Concentrations tended to be highest in summer, lower in spring, and lowest in winter. Indoor and personal air concentrations were generally comparable and were usually much higher than outdoor air concentrations. Inhalation exposure exceeded dietary exposure for cyclodiene termiticides and for pesticides used mainly in the home. Dietary exposures were greater for many of the other pesticides. Inhalation risks were uncertain for termiticides (depending on rates of degradation) but were negligible for other pesticides. The data were insufficient to support risk assessments for food, dermal contact, or house dust exposures.     

HIV behavioral surveillance among the U.S. general population

HIV behavioral surveillance in the United States is conducted among three groups: infected populations, high-risk populations, and the general population. We describe the general population component of the overall U.S. HIV behavioral surveillance program and identify priority analyses. This component comprises several data systems (ongoing, systematic, population-based surveys) through which data on risk behaviors and HIV testing are collected, analyzed, and disseminated. Multiple data systems are needed to balance differences in scope and purpose, as well as strengths and weaknesses of the sampling frames, mode of administration, and frequency of data collection. In a concentrated epidemic, such as in the United States, general population data play a small but important role in monitoring the potential spread of infection more broadly, particularly given increases in HIV transmission through heterosexual contact.     

芽孢杆菌降解有机磷农药的研究

目的 筛选出既能降解农药又有抑制霉菌的芽孢杆菌,并测定此芽孢杆菌的最佳生长条件。方法 本实验以有机磷农药为试验用培养基中惟一氮源筛选出10株能分解有机磷农药的芽孢杆菌,并测试其抑制霉菌作用,摸索菌株最适生长条件。结果 筛选得到的降解农药的7号菌株,有抑制霉菌生长作用,培养温度为35℃,pH7.0。结论 芽孢杆菌能够抑制霉菌并且降解有机磷农药。