辽宁省一般人群全血和尿液中铬水平分析

目的 了解2009-2010年辽宁省一般人群全血和尿液中铬水平(以下简称血铬、尿铬),分析其流行病学特点。方法 2009-2010年采用整群随机抽样方法,从辽宁省内东、中、西部3个城市抽取2105名6~60岁一般人群作为研究对象,对其生活环境和健康状况问卷调查,并分别采集2105份静脉抗凝血和1691份尿样,应用电感耦合等离子体质谱法检测血铬、尿铬水平,分析不同年龄、性别和区域人群的分布情况。结果 辽宁省一般人群血铬几何均数为0.53μg/L,中位数为0.3μg/L,P₉₅为2.92μg/L;男性和女性几何均数分别为0.49、0.58μg/L(P<0.01);6~12、13~16、17~20、21~30、31~45、46~60岁年龄组血铬几何均数分别为0.38、0.57、0.66、0.55、0.57和0.52μg/L(P<0.01);东、中、西部地区人群血铬几何均数分别为0.32、1.23、0.42μg/L(P<0.01)。辽宁省一般人群尿铬几何均数低于检出限0.42μg/L,对不同特征中尿铬高于检出限人数分布比较结果显示,不同年龄、地域人群尿铬水平差异有统计学意义(P<0.01)。结论 辽宁省血铬、尿铬水平均低于全国一般人群血铬、尿铬水平,本研究为进一步开展铬的生物监测、鉴别排除职业禁忌症等研究提供了基础数据。     

山区农村散居80岁及以上老年人营养调查

对象与方法：在沂蒙山区对４个乡镇的散居高龄老人１２１人进行营养调查（男５５,女６６）,年龄最高男９６岁,女９２岁;最低男女均为８０岁。以称重法与五日询问回忆法相结合,进行四季动态的膳食调查。结果：其膳食构成以谷类（占总重量６１％～７１％）及蔬菜（１２％～１６％）为主,配有少量豆类（１．８％～４．６％）与动物性食品（６．２％～１２．０％）。按中国营养学会８０岁以上老人ＲＤＡ计算,四季能量摄入男性达到ＲＤＡ的８１％～９１％,女性达到７５％～８４％,蛋白质男性仅达到６７％～７５％,女性５５％～６７％,动物和豆类蛋白质来源不足,低于蛋白质总量的３０％～５０％。钙摄入量只有ＲＤＡ的２０％左右,锌、硒、维生素Ａ、Ｂ１、Ｂ２、Ｃ均明显不足。三大营养素所占能量比例合理,脂肪来源以植物油为主,符合老年人营养要求。营养缺乏病检查发现有维生素不足症状,如皮肤干燥鳞皮占４．１％,口角湿白厚２８．９％,舌腥红２２．３％,味蕾肥大８１．０％,膝反射消失１２．４％等。临界高血压患病率为１６．１％,高血压患病率１４．３％。生化检查：血红蛋白检测１１４人,低于１２０ｇ／Ｌ者１６．７％;血糖检测１１６人,高于正常的占６．９％,低于正常的占４７?     

Characterisation of exposure to total and hexavalent chromium of welders using biological monitoring

Inhalation exposure to total and hexavalent chromium (TCr and HCr) was assessed by personal air sampling and biological monitoring in 53 welders and 20 references. Median inhalation exposure levels of TCr were 1.3, 6.0, and 5.4 μg/m³ for welders of mild steel (MS, <5% alloys), high alloy steel (HAS, >5% alloys), and stainless steel (SS, >26% alloys), respectively. The median exposures to HCr compounds were 0.23, 0.20, and 0.08 μg/m³, respectively. Median concentrations of TCr in urine, blood plasma and erythrocytes were elevated in all welders, compared with the corresponding median concentrations in the reference group (p < 0.005). The TCr levels observed in plasma were two-fold higher in welders of SS and HAS than in welders of MS (p < 0.01). Exposure to HCr as indicated by median total content of Cr in erythrocytes was 10 μg/L in welders of SS, MS and HAS. Uptake of TCr during the shift was confirmed for welders of SS by a median increase of urinary TCr from pre- to post-shift of 0.30 μg/g creatinine. For welders of MS and HAS as a group TCr was not increased.     

富铬豆浆对糖尿病大鼠血糖及血脂的影响

研究富铬豆浆对四氧嘧啶所致实验性糖尿病大鼠的血糖及血脂的影响。用氯化铬浸泡大豆并发芽 ,通过生物富集和生物转化作用 ,使部分无机铬转化为有机形式并富集在豆芽中 ;对糖尿病大鼠连续灌胃普通豆浆 [Cr0 2 5 μg (d·kgBW) ]、低剂量富铬豆浆 [Cr30 μg (d·kgBW) ]和高剂量富铬豆浆 [Cr30 0 μg (d·kgBW ) ]四周 ,每周末尾静脉采血 ,测定血糖、总胆固醇 (TC)、甘油三酯 (TG)、低密度脂蛋白 (LDL)、高密度脂蛋白 (HDL)及胰岛素含量。结果显示 ,富铬豆浆组大鼠血糖水平、胰岛素、TC、TG、LDL及胰岛素明显降低 ,而HDL明显升高。高剂量富铬豆浆组的降糖作用明显高于其它组。结论 :富铬豆浆可以改善糖代谢和脂代谢 ,可以用来预防和治疗糖尿病     

铬中毒性肾损害与铬结合物关系的研究

本研究采用ＳｅｐｈａｄｅｘＧ５０凝胶层析技术，对铬中毒大鼠肾、尿中铬结合物进行了分离和测定，并分析了各种铬结合物与肾损害的关系。实验结果提示，低分子铬结合物（ＬＭＷ－Ｃｒ）是铬的主要排泄形式，与铬的解毒可能有密切关系；随着肾损害进展小分子铬结合物（ＭＭＷ－Ｃｒ）出现并明显增多，反映了机体形成ＬＭＷ－Ｃｒ能力的紧张，ＭＭＷ－Ｃｒ可能是攻击靶器官的主要活性因素；高分子铬结合物（ＨＭＷＣｒ）的增多可能是ＭＭＷＣｒ增加导致铬与生物活性大分子结合的结果     

25家电镀企业中铬污染现状和作业者接触情况

目的 了解电镀企业铬污染现状和工人铬接触情况,寻找有效的铬接触生物标记物,为铬污染的防治提供科学依据.方法 采用整群抽样的方式抽取杭州市25家使用6价铬的电镀企业,进行职业卫生现场调查和空气中铬浓度检测,并对157名铬接触工人和93名非接触工人进行健康调查和体内红细胞中铬含量检测.结果 车间空气中6价铬短时间接触浓度中位数为0.06 mg/m3,范围0.01(检出限)～0.53 mg/m3,合格率89.4％;其中超标岗位均为电镀岗位,中位数0.10 mg/m3,范围0.01(检出限)～0.53 mg/m3,合格率76.3％.铬接触工人红细胞内铬含量的中位数为4.41( 2.50～5.29) μg/L,显著高于对照人群[1.54 (0.61～2.98) μg/L,P＜0.01).按性别、年龄、吸烟、饮酒分层后,除了小于30岁的人群(P=0.11),其余各层内两组间的差异都有统计学意义(P＜0.05).在接触工人中,吸烟者红细胞内铬含量[4.98(2.90～6.37) μg/L]明显高于不吸烟的人群[3.58( 2.25～4.40) μg/L],差异有统计学意义(P＜0.05).结论 杭州市电镀作业环境中存在6价铬污染,电镀作业工人体内铬负荷显著高于对照人群.应降低作业环境中铬浓度,加强工人个体防护,降低6价铬对工人的危害.     

藻酸双酯钠铬配合物的制备及其理化性质的初步研究

目的 制备藻酸双酯钠(PSS)的铬配合物.并研究其溶解性、颜色、分子量等理化性质和光谱表征.方法 将PSS与三价铬离子在不同pH条件下进行络合.制备PSS铬配合物(PSS-Cr),采用正交实验优化制备条件.并采用UV、IR、HPGPC、原子吸收和电导滴定等分析方法 对PSS-Cr的结构和基本理化性质进行初步分析.结果 与结论 制备PSS-Cr的最适条件为:温度为50℃.pH值为7,PSS(以单糖计)与铬的摩尔比为2:1,在此条件下制备的PSS-Cr中的铬含量迭6.69%,重均相对分子质量为12188Da.     

Carcinogenic chromium(VI)-induced protein oxidation and lipid peroxidation: implications in DNA-protein crosslinking

Hexavalent chromium [Cr(VI)] compounds are Group-I human carcinogens. Cr(VI)-induced DNA-protein crosslinks (DPCs) have been implicated in the mutagenic and carcinogenic effects of Cr(VI). Although multiple mechanisms have been suggested for Cr(VI)-induced DNA-protein crosslinking, the mechanism of formation of DNA-protein crosslinks is not well understood. In this study, we explored the hypothesis that Cr(VI)-induced DPCs could be formed via generation of protein carbonyls and malonaldehyde (MDA) through protein oxidation and lipid peroxidation, respectively. Treatment of human leukemic T-lymphocyte MOLT4 cells with potassium chromate induced the formation of protein carbonyls and DPCs within 2 h, but increased the level of MDA only after 4 h, in a dose-dependent manner. Chromate treatment of MOLT4 cell homogenates also resulted in increased formation of MDA and protein carbonyls in a dose-dependent manner. EPR spectrometry in combination with spin trapping techniques revealed that reaction of Cr(VI) with biological reductants such as NADPH, glutathione reductase or H(2)O(2) generates Cr(V) and (*)OH radicals. Pretreatment of cells with antioxidants such as alpha-tocopherol or Tiron inhibited chromate-induced increase in formation of protein carbonyls, MDA and DPCs, but pretreatment of cells with riboflavin or 3-aminotriazole, a catalase inhibitor, had the opposite effect. Our results, for the first time, demonstrate that Cr(VI) exposure increases the cellular level of protein carbonyls and that Cr(VI)-induced DPCs may be formed, at least in part, via generation of protein carbonyls.     

Java medaka: a proposed new marine test fish for ecotoxicology

Java medaka (Oryzias javanicus), which is distributed in estuarine waters of East to Southeast Asia, is proposed here for consideration as a new marine test fish. Semi-static acute toxicity tests were conducted at 26 degrees C for 1 week, 2 weeks, and 1 month old Java-medaka exposed to 4-chlorophenol and zinc, and 2 weeks olds exposed to potassium dichromate (hexavalent chromium) and sodium hypochlorite (residue chlorine). Ninety-six hours LC50s of 4-chlorophenol, zinc, hexavalent chromium, and residue chlorine were from 3.0 to 4.1, from 12.4 to 14.7, 7.4, and 0.05 mg/L, respectively. There were no large differences in sensitivity for 4-chlorophenol and zinc among the three growth stages. Compared with other fish species, these LC50s were relatively low suggesting that Java medaka has relatively high sensitivity to chemicals. This fish is quite easy to keep in the laboratory, with low mortalities at early stages and it takes about 3 months to mature from hatching, suggesting that this fish can be used not only for short-term toxicity tests but also for early life stage toxicity tests. From these results, Java-medaka is highly recommended as a marine test fish for ecotoxicity tests.     

铬酵母中铬的含量测定

目的 研究铬酵母中铬的含量测定方法。方法 采用氧化－光度法。结果 铬的平均回收率及相对标准偏差分别为１００．３％、２．７％（ｎ＝５）。结论 本方法可用于测定铬酵母中铬的含量,方法简便,易行。