铬负荷与铬中毒性肾损害关系的实验研究

在亚慢性铬中毒性肾损害动物模型研究发现：当血铬在６．６ｍｇ／ｍｌ以下时血铬与尿铬排泄率和肾铬水平呈明显正相关；当血铬超过６．６ｍｇ／ｍｌ时，尿铬排泄率开始下降，肾铬水平无明显增加。尿Ｌｙｓ、尿蛋白和ＧＦＲ出现异常的尿铬临界浓度分别为５．９０、７．５７和９．３６ｕｇ／ｍｇ肌酐。尿Ｌｙｓ和尿蛋白出现异常的肾皮质铬临界浓度分别是３６．７ｐｐｍ和４１．８ｐｐｍ。     

铅作业工人肾功能的调查研究

对139名铅作业工人和51名无职业性铅接触史的城市居民进行调查。结果:铅作业工人尿肌酐(Cr)排出减少,血Cr含量增加,血中尿素氨含量增加,溶菌酶(Lys)含量减少。尿cr与尿ALA呈显著负相关,尿Lys与ALA呈显著正相关。尿Lys和血Cr含量在铅接触工人中存在明显的性别差异。表明职业性铅接触可引起肾脏损害,且存在明显的性别差异。     

江苏某电池厂工人血铅、血镉和尿镉的浓度及相关性

目的了解江苏某电池厂工作人员体内血铅、血镉和尿镉的浓度,对三者的关系进行比较分析。方法选择该电池厂437名员工为研究对象,并测定其体内的血铅、血镉、尿镉含量。结果血铅<400μg/L和≥400μg/L组血镉的均值分别为1.23μg/L和2.10μg/L,差异有统计学意义(t=-3.758,P<0.01);两组尿镉均值分别为1.03μg/g肌酐和1.10μg/g肌酐,差异无统计学意义(t=-0.618,P>0.05)。血镉与血铅之间存在相关关系(r=0.238,P<0.01),尿镉与血铅之间无相关关系(r=0.051,P>0.05)。结论该工厂工人体内血铅、血镉、尿镉含量均存在一定异常,血铅和血镉之间存在相关关系。为减少铅、镉行业对从业人员的健康损害,需要政府部门、企业、从业人员的共同努力。     

血清CysC、β2-MG、尿微量白蛋白/尿肌酐比值与糖尿病肾病患者尿蛋白的相关性

目的探讨血清胱抑素C(CysC)、β2-微球蛋白(β2-MG)、尿微量白蛋白/尿肌酐比值与糖尿病肾病患者尿蛋白的相关性。方法选取2018年3月至2019年5月在本院门诊或住院部就诊的2型糖尿病患者216例,根据24 h尿微量白蛋白排泄率分为Ⅰ期组104例、Ⅱ期组70例、Ⅲ期组42例;选取同期健康志愿者100例为对照组。检测晨尿样本中的微量白蛋白、尿肌酐及24 h尿样本中尿微量白蛋白水平,根据尿量计算排泄率;检测血清CysC、β2-MG水平。结果Ⅰ期组、Ⅱ期组、Ⅲ期组患者血清CysC、β2-MG、尿微量白蛋白/尿肌酐比值明显高于对照组,Ⅱ期组、Ⅲ期组明显高于Ⅰ期组,Ⅲ期组明显高于Ⅱ期组,上述差异均有统计学意义(均P<0.05)。Ⅱ期组、Ⅲ期组患者尿微量白蛋白排泄率明显高于Ⅰ期组和对照组,差异均有统计学意义(均P<0.01);Ⅲ期组患者尿微量白蛋白排泄率(819.62±74.39)mg/24 h明显高于Ⅱ期组(153.05±41.39)mg/24 h,差异有统计学意义(P<0.01)。血清CysC、β2-MG、尿微量白蛋白/尿肌酐与尿微量白蛋白排泄率均呈正相关(均P<0.05)。结论随着糖尿病肾病患者尿蛋白程度进展,血清CysC、β2-MG、尿微量白蛋白/尿肌酐比值均升高。     

环境镉暴露与肿瘤危险性

在探讨环境镉暴露与肿瘤的关系的研究中,对994名随机选取的研究对象进行24h尿镉和庭院土壤中镉含量测定,并对研究起始至2004年6月30日肿瘤的发病情况进行监测。用Cox回归计算内部与外部镉暴露的危险比。结果发现,土壤中镉含量为0.8～17.0mg/kg。研究起始高暴露区尿镉排泄量高于低暴露区排泄量,有统计学意义。随访期间共发生50例恶性肿瘤和20例良性肿瘤,其中,肺部肿瘤分别为恶性18例、良性1例。全癌症危险度与2倍24h镉排泄量显著相关。高暴露区肺癌人群归因危险度百分比为67%。2倍24h尿镉排泄量、高暴露区相对低暴露区、土壤中2倍镉浓度的肺癌调整危险比分别为1.70、4.17、1.57。可见,非铁冶炼厂镉污染仍是一个严重的健康问题,急需采取有针对性的防护措施。     

不同校正方法对尿铅、尿镉浓度影响的研究

分析了肌酐代谢无明显异常的17名铅、镉接触者在自由饮水条件下收集的132份尿样。用尿比重(U_(SG))、尿肌酐(U_(Cr))、尿流速调整的肌酐比率(U_(CF))等方法校正尿测定浓度(U),比较其对尿铅、尿镉浓度的影响。结果表明,不同方法校正后的变异程度,以U_(CF)时最大,其次为U_(Cr)、U_(SG)校正,未校正的测定浓度(U)的变异程度最小。因此,可以认为,U_(SG)、U_(Cr)、U_(CF)校正与测定浓度相比,并未提供明显的优点。就尿铅、尿镉而言,在特殊情况下需校正时,以尿比重为参数较为合适。     

夏津县正常儿童尿碘、尿肌酐排泄量的调查

在正常情况下 ,单位时间的排碘量与 2 4h排碘量相关。尿肌酐的排泄量在 2 4h内虽有波动 ,但多数人比较稳定 ,因此 ,尿碘与尿肌酐也是相关的。目前 ,在地甲病的普查防治工作中 ,由于收集 2 4h尿比较困难 ,所以常采用随机尿检测尿碘及尿肌酐比值 ,从而推算出 2 4h尿碘排泄量。近年来 ,我区发现高碘性地甲病 ,但缺乏儿童 2 4h尿碘排泄量的对照。为了解我县正常儿童 2 4h尿碘、尿肌酐排泄情况 ,找出尿肌酐系数 ,对本县朱庙乡联中 1～ 6年级的 77名学生进行了调查。1　概况当地群众日常生活以自产自食为主 ,由于饮水含碘量的多寡直接影响尿碘 ,因…     

镉对去卵巢大鼠钙代谢的影响

目的 研究镉对去卵巢大鼠钙代谢的影响。方法 将SD大鼠行人工去卵巢术，分别经饮人不同剂量（50，100，200mg/L）的镉染毒24周。分别于第6，12，18，34周收集24h尿液、粪便。用石墨炉原子吸收法测定血、尿镉，放射免疫法测定血清雌二醇、尿β2－微球蛋白，同时测定粪、尿及骨钙含量，计算粪钙及尿钙日排泄总量。结果 大鼠去卵巢后，体内雌二醇明显下降。镉染毒后，去卵巢大鼠粪钙及尿钙日排泄总量明显升高，且呈剂量－反应关系，200mg/L镉染毒组去卵巢大鼠的骨钙含量也显著性下降。同时镉染毒的去卵巢大鼠发生肾损害，表现为尿β2－微球蛋白排汇增加，尿钙日叫量与β2－微球蛋白显著性正相关。结论 镉可导致去卵巢大鼠钙代谢损害，肠钙及尿钙的排泄量增加，使骨钙含量降低。     

尿中肌酐排泄稳定性的研究

分析在自由饮水条件下７７３个健康人的一次点尿样，６２人的２４ｈ尿样及８人连续５天收集的２４ｈ尿样，对这些尿样分别测定比重、肌酐浓度及肌酐排泄量，以揭示尿肌酐排泄的稳定性。研究发现，尿肌酐浓度与尿比重之间具有一定的相关性，尿肌酐排泄存在明显的个性差异和体内变异。可以认为，肌酐排泄的稳定性较差，用肌酐作为尿毒物浓度的校正参数，其适合性和可靠性值得怀疑。     

深圳市产妇、新生儿和少儿体内重金属负荷水平研究

目的了解深圳市敏感人群体内铬、砷、镉、汞、铅5种重金属的负荷水平。方法选择环境重金属污染敏感人群(包括产妇、新生儿和3~5年级儿童),采集产妇静脉血、胎儿脐血、儿童静脉血以及产妇和儿童的尿液,采用电感耦合等离子体质谱法测定全血和尿液中镉、铅、铬、砷、汞的含量。结果产妇静脉血中铬、砷、镉、汞、铅质量浓度分别为2.58、1.57、0.99、1.66和18.52μg/L,新生儿脐带血重金属质量浓度分别为1.63、1.49、0.03、3.28和15.38μg/L;产妇尿中5种重金属的质量浓度分别为4.41、94.85、1.58、2.02和6.14μg/g·肌酐,尿镉和尿汞超标率分别为2.63%和7.14%;儿童静脉血中铬、砷、镉、汞、铅质量浓度分别为3.90、1.94、0.48、1.67和30.85μg/L,3名儿童血铅超标,尿中5种重金属的质量浓度分别为4.19、107.67、0.79、1.20和4.21μg/g·肌酐,仅1名儿童尿砷超标,12名儿童尿汞超标;尿样与血样中砷、镉、汞质量浓度呈显著正相关(P0.05)。结论人体生物样本中重金属质量浓度个体差异较大,本次调查的深圳地区重金属污染敏感人群(产妇、新生儿和儿童)体内重金属负荷水平远低于大多数其它国家和地区,但仍存在重金属铅、砷、汞、镉超标情况。     

Mobilisation of heavy metals into the urine by CaEDTA: relation to erythrocyte and plasma concentrations and exposure indicators

To investigate the effects of calcium disodium ethylenediamine tetra-acetate (CaEDTA) on the urinary excretion, erythrocyte, and plasma concentrations and exposure indicators of seven heavy metals, CaEDTA was administered by intravenous infusion to 20 workers exposed to lead, zinc, and copper. The workers' blood lead concentrations ranged from 22 to 59 micrograms/dl (mean 38 micrograms/dl (1.8 mumol/l]. The 24 hour urinary excretion of metals after CaEDTA administration (mobilisation yield) was on average 13 times the background excretion for lead, 11 times for zinc, 3.8 times for manganese, 3.4 times for cadmium, 1.3 times for copper, and 1.1 times for chromium; no significant increase was found for mercury. The mobilisation yield of lead (MPb) was significantly correlated with whole blood and erythrocyte concentrations and the urinary excretion of lead but not with its plasma concentration; similarly, the mobilisation yield of cadmium was significantly correlated with its erythrocyte concentration. In addition, MPb was significantly correlated with intra-erythrocytic enzyme delta-aminolaevulinic acid dehydratase activity and urinary coproporphyrin excretion. The relation between the mobilisation yield of heavy metals and their body burden (and toxic signs) is discussed in the light of these findings.     

Mobilisation of heavy metals into the urine by CaEDTA: relation to erythrocyte and plasma concentrations and exposure indicators.

To investigate the effects of calcium disodium ethylenediamine tetra-acetate (CaEDTA) on the urinary excretion, erythrocyte, and plasma concentrations and exposure indicators of seven heavy metals, CaEDTA was administered by intravenous infusion to 20 workers exposed to lead, zinc, and copper. The workers' blood lead concentrations ranged from 22 to 59 micrograms/dl (mean 38 micrograms/dl (1.8 mumol/l]. The 24 hour urinary excretion of metals after CaEDTA administration (mobilisation yield) was on average 13 times the background excretion for lead, 11 times for zinc, 3.8 times for manganese, 3.4 times for cadmium, 1.3 times for copper, and 1.1 times for chromium; no significant increase was found for mercury. The mobilisation yield of lead (MPb) was significantly correlated with whole blood and erythrocyte concentrations and the urinary excretion of lead but not with its plasma concentration; similarly, the mobilisation yield of cadmium was significantly correlated with its erythrocyte concentration. In addition, MPb was significantly correlated with intra-erythrocytic enzyme delta-aminolaevulinic acid dehydratase activity and urinary coproporphyrin excretion. The relation between the mobilisation yield of heavy metals and their body burden (and toxic signs) is discussed in the light of these findings.     

Adjustment of urinary concentration to urinary volume in relation to erythrocyte and plasma concentrations: an evaluation of urinary heavy metals and organic substances

The effects of urinary volume on adjusted and nonadjusted urinary excretion of 11 heavy metals and organic substances were examined in relation to plasma and erythrocyte concentrations in 19 metal workers under conditions of water restriction and loading. Blood lead concentrations in these workers ranged from 25 to 59 micrograms/dl. The results indicated that: urinary volume significantly affects not only nonadjusted urinary concentration for all substances, but also affects timed excretion and concentrations adjusted to urinary specific gravity and to urinary creatinine for most substances; the concentration adjusted to urinary volume is, on the other hand, independent of urinary volume; and urinary excretion of lead and mercury is related more closely to erythrocyte concentration than to plasma concentration. This last finding reflects complex renal excretory mechanisms for these heavy metals.     

Cadmium in blood and urine related to present and past exposure. A study of workers in an alkaline battery factory

Blood and urinary cadmium concentrations together with cadmium in air concentrations from the breathing zone of 18 male workers in an alkaline battery factory were determined at regular intervals for 11 consecutive weeks. Nine of the workers examined were smokers and nine non-smokers. Smokers and non-smokers did not differ in age or years of employment. Cadmium in air concentrations varied, but no definite trend was observed. The concentrations of cadmium in the blood and urine were found to be stable. Exposure to airborne cadmium was identical for smokers and non-smokers but average cadmium concentrations in the blood and urine of smokers were approximately twice as high as those in non-smokers. For the whole group, urinary cadmium was significantly correlated with years of employment, but no correlation was found between blood cadmium concentrations and exposure. For non-smokers, the correlation between cadmium in blood and years of employment was statistically significant (p less than 0.001). This finding indicated that blood concentrations of cadmium reflect body burden in non-smokers at current low exposure levels.     

Cadmium in blood and urine related to present and past exposure. A study of workers in an alkaline battery factory.

Blood and urinary cadmium concentrations together with cadmium in air concentrations from the breathing zone of 18 male workers in an alkaline battery factory were determined at regular intervals for 11 consecutive weeks. Nine of the workers examined were smokers and nine non-smokers. Smokers and non-smokers did not differ in age or years of employment. Cadmium in air concentrations varied, but no definite trend was observed. The concentrations of cadmium in the blood and urine were found to be stable. Exposure to airborne cadmium was identical for smokers and non-smokers but average cadmium concentrations in the blood and urine of smokers were approximately twice as high as those in non-smokers. For the whole group, urinary cadmium was significantly correlated with years of employment, but no correlation was found between blood cadmium concentrations and exposure. For non-smokers, the correlation between cadmium in blood and years of employment was statistically significant (p less than 0.001). This finding indicated that blood concentrations of cadmium reflect body burden in non-smokers at current low exposure levels.     

Renal function of workers with low-level cadmium exposure

The influence of occupational exposure to cadmium on renal function was examined in 27 male cadmium workers from plants with second-degree usage of cadmium. The levels of cadmium in the blood and urine and various protein concentrations in the urine and serum were determined. The urinary levels of beta 2-microglobulin, retinol-binding protein, and N-acetyl-beta-D-glucosaminidase were statistically significantly increased in workers with urinary cadmium levels above 50 nmol/l. SDS-PAGE electrophoresis with silver staining is probably a sensitive indicator of the early effects of cadmium on protein excretion. The currently recommended biological exposure limits may have to be lowered.     

Adjustment of Creatinine-Adjusted Value to Urine Flow Rate in Lead Workers

Two male lead workers, aged 57 and 51 y, were studied to compare the urinary flow/creatinine-adjusted values published earlier by Araki et al. and by Greenberg and Levine. We collected 24-h urine samples once a month for 31 mo and 16 mo for workers 1 and 2, respectively. The workers' urinary excretions of lead, delta-aminolevulinic acid, and coproporphyrin were measured. No significant correlations between urine flow rate and urinary flow/creatinine-adjusted values published by Araki et al. for the three substances were found for these two workers. However, urinary flow/creatinine-adjusted values presented by Greenberg and Levine for lead and delta-aminolevulinic acid were correlated positively with urine flow rate in the two workers, and their adjusted value for coproporphyrin was correlated positively with urine flow rate in one of the workers. We concluded that use of the urinary flow/creatinine-adjusted value by Greenberg and Levine for biological monitoring poses a problem because of the theoretical fallacy.     

Measurement of vitamin D3 metabolites in smelter workers exposed to lead and cadmium

OBJECTIVES: To investigate the effects of lead and cadmium on the metabolic pathway of vitamin D3. METHODS: Blood and urinary cadmium and urinary total proteins were measured in 59 smelter workers occupationally exposed to lead and cadmium. In 19 of these workers, the plasma vitamin D3 metabolites, (25-hydroxycholecalciferol (25 OHD3), 24R, 25-dihydroxycholecalciferol (24R,25(OH)2D3) and 1 alpha,25- dihydroxycholecalciferol (1 alpha, 25(OH)2D3)) were measured together with blood lead. Vitamin D3 metabolites were measured by radioimmunoassay, (RIA), lead and cadmium by atomic absorption spectrophotometry, and total proteins with a test kit. RESULTS: Ranges for plasma 25(OH)D3, 24R,25(OH)2D3 and 1 alpha,25(OH)2D3 were 1.0-51.9 ng/ml, 0.6-5.8 ng/ml, and 0.1-75.7 pg/ml, respectively. Ranges for blood lead were 1-3.7 mumol/l, (21-76 micrograms/dl), blood cadmium 6- 145 nmol/l, and urinary cadmium 3-161 nmol/l. Total proteins in random urine samples were 2.1-32.6 mg/dl. Concentrations of lead and cadmium in blood showed no correlation (correlation coefficient -0.265) but there was a highly significant correlation between blood and urinary cadmium. Concentrations for 24R,25(OH)2D3 were depressed below the normal range as blood and urinary cadmium increased, irrespective of lead concentrations. High cadmium concentrations were associated with decreased plasma 1 alpha,25(OH)2D3 when lead concentrations were < 1.9 mumol/l and with above normal plasma 1 alpha,25(OH)2D3 when lead concentrations were > 1.9 mumol/l, Kruskal-Wallis analysis of variance (K-W ANOVA) chi 2 = 10.3, p = 0.006. Plasma 25(OH)D3 was negatively correlated with both urinary total proteins and urinary cadmium, but showed no correlation with plasma 24R,25(OH)2D3, 1 alpha,25(OH)2D3, blood lead, or blood cadmium. CONCLUSION: Continuous long term exposure to cadmium may result in a state of equilibrium between blood and urinary cadmium. Cadmium concentrations in blood could be predicted from the cadmium concentration of the urine, (regression coefficient +0.35 SE 0.077). Exposure to cadmium alone decreased the concentrations of 1 alpha,25(OH)2D3 and 24R,25(OH)2D3, whereas exposure to both cadmium and lead increased the concentrations of 1 alpha,25(OH)2D3. It has been suggested that cadmium and lead interact with renal mitochondrial hydroxylases of the vitamin D3 endocrine complex. Perturbation of the vitamin D metabolic pathway by cadmium may result in health effect, such as osteoporosis or osteomalacia, risks which are possibly increased in the presence of lead.

 

     

八种校正参数对尿毒物浓度影响的研究

本研究采用尿比重（Ｕ＿（ＳＧ））、尿肌肝（Ｕ＿（Ｃｒ））、比重校正的尿肌酐（Ｕ＿（ＳＧ－Ｃｒ））、尿流速校正的肌酐比率（Ｕ＿（ＣＦ）ｂ，ｂ值分别为０．６７、０．３３、０，２７和０．１６）等参数，校正肌酐代谢正常的１７名铅、镉接触者在自由饮水条件下收集的１３２份尿样的测定浓度（Ｕ），以揭示其对尿铅、镉浓度的影响。研究表明，尿肌酐、铅、偏排泄存在明显的个体差异和体内变异。不同参数校正后的变异系数，尿铅以Ｕ＿（ＣＦ）０．６７最大，其次为Ｕ＿（Ｃｒ）、Ｕ＿（ＳＧ－Ｃｒ）、Ｕ＿（ＳＧ），测定浓度（Ｕ）最小，尿镉仍以Ｕ＿（ＣＦ）０．６７最大，Ｕ＿（Ｃｒ）、Ｕ＿（ＳＧ）次之，Ｕ＿（ＳＧ－Ｃｒ）最小。因此，可以认为，Ｕ＿（ＳＧ）、Ｕ＿（Ｃｒ）、Ｕ＿（ＳＧ－Ｃｒ）、Ｕ＿（ＣＦ）ｂ与尿铅的Ｕ相比，并未提供明显优点，而尿镉以Ｕ＿（ＳＧ－Ｃｒ）的校正效果较好。就Ｕ＿（ＣＦ）ｂ而言，变异系数随校正指数减小而缩小，本研究得出的校正指数（０．１６）的校正效果优于０．６７、０．３３和０．２７。     

Reliability of studies of iodine intake and recommendations for number of samples in groups and in individuals

The iodine intake level in a population is determined in cross-sectional studies. Urinary iodine varies considerably and the reliability of studies of iodine nutrition and the number of samples needed is unsettled. We performed a longitudinal study of sixteen healthy men living in an area of mild to moderate iodine deficiency. Iodine and creatinine concentrations were measured in spot urine samples collected monthly for 13 months. From these data we calculated the number of urine samples needed to determine the iodine excretion level for crude urinary iodine and for 24 h iodine excretion estimated from age- and gender-specific creatinine excretions. We found that mean urinary iodine excretion varied from 30 to 87 microg/l (31 to 91 microg/24 h). Sample iodine varied from 10 to 260 microg/l (20 to 161 microg/24 h). Crude urinary iodine varied more than estimated 24 h iodine excretion (population standard deviation 32 v. 26; individual standard deviation 29 v. 21; Bartlett's test, P < 0.01 for both). The number of spot urine samples needed to estimate the iodine level in a population with 95 % confidence within a precision range of +/- 10 % was about 125 (100 when using estimated 24 h iodine excretions), and within a precision range of +/- 5 % was about 500 (400). A precision range of +/- 20 % in an individual required twelve urine samples or more (seven when using estimated 24 h iodine excretions). In conclusion, estimating population iodine excretion requires 100-500 spot urine samples for each group or subgroup. Less than ten urine samples in an individual may be misleading.