Effects of iron, tin, and copper on zinc absorption in humans

Zinc absorption as measured by body retention of [65Zn]zinc chloride or a turkey test meal extrinsically labeled with 65Zn was determined in human subjects by whole body counting after 7 days. Average 65Zn absorption from zinc chloride in persons with a high iron-absorbing capacity was similar to persons with a low capacity to absorb iron. Inorganic iron, 920 mumol (51 mg), or HB iron, 480 mumol (26 mg), inhibited 65Zn absorption from 92 mumol (6 mg) of zinc chloride. When 610 mumol of iron (34 mg) was added to a turkey test meal containing 61 mumol of zinc (4 mg), 65Zn absorption was not inhibited. Tin, 306 mumol (36 mg), given with zinc chloride or turkey test meals (61 mumol, 4 mg, of Zn) significantly reduced 65Zn absorption. Copper, 79 mumol (5 mg), had no significant effect on the 65Zn absorption from 7.9 mumol (0.5 mg) of zinc chloride. In summary, the capacity to absorb iron did not influence 65Zn absorption, but both inorganic iron and heme-iron inhibited 65Zn absorption from zinc chloride. Inorganic iron had no effect, however, on 65Zn absorption from the turkey test meal. Tin in a large dose also inhibited 65Zn absorption from both zinc chloride and the turkey test meal.     

锌的排铅作用及对铜 铁元素的影响

目的:探讨锌的排铅作用及对血液和股骨中铜、铁元素的影响。方法:小鼠连续30 d饮用0.55%醋酸铅水溶液制作铅中毒模型,同时硫酸锌水溶液灌胃为加锌组,依地酸二钠钙注射为阳性药物对照。结果:加锌组小鼠血铅和股骨铅明显降低,血铁和股骨锌含量明显高于铅中毒模型组;其股骨中的锌、铁和锌/铜均明显高于依地酸二钠钙组。结论:硫酸锌对于铅中毒小鼠具有促进排铅作用,它在维持小鼠股骨中微量元素方面优于依地酸二钠钙。     

珠海市小学生营养不良与血清中铁、锌、铜含量的相关性研究

目的了解珠海市小学生营养不良与微量元素铁、锌、铜的关系,为提高营养不良与微量元素缺乏的预防和治疗,提供科学的理论和实验依据。方法采用电感耦合等离子体质谱仪。测定242例营养不良小学生血清中的微量元素铁、锌、铜的含量及缺乏率,与正常对照组进行对比。结果①营养不良小学生的缺锌率最高达22.31%,缺铁率次之为20.66%,铜的缺乏率最少为6.20%,随着年龄的增加缺铁、锌率也随之增加。②营养不良小学生的缺铁率女生明显高于男生,差异有统计学意义(P<0.05)。锌、铜的缺乏率男女生无统计学意义,城市和农村的铁、锌、铜缺乏率的差异无统计学意义。③营养不良小学生血清中的铁、锌、铜的含量明显低于营养正常小学生,差异有统计学意义(P<0.01)。结论小学生营养不良与微量元素铁、锌、铜缺乏有密切关系,治疗营养不良时要注意微量元素的补充。     

Evaluation of trace trace elements iron, zinc, copper and lead in the diet of female university students

Food consumption of 50 female students in Universiti Kebangsaan Malaysia was recorded for 7 days. Foods and drinks most frequently consumed were selected for analysis of iron, zinc, copper and lead content. The mean daily intakes of energy, protein, carbohydrate and fat among the students are 6.5±1.4 MJ (1550±335 kcal), 59.8±18.5g, 227.1±54.6 g and 46.0±11.5 g respectively. This diet contributed 19.6-6.4 mg Fe, 7.0-2.0 mg Zn and 1.6-0.6 mg Cu per day which were lower than the Malaysian RDA for Fe and US RDA for Zn, while Cu is within the recommended range. The main sources of these minerals in the student's diet were rice, rice products, meat and animal products. Lead concentration in the diet (134±77 ug/day) is below the acceptable daily intake (ADI) value suggested by Codex Alimentarius Commission (1984). This study indicated concern regarding the low intake of the essential trace elements on long term basis among the students.     

Tin, copper, iron and calcium metabolism of rats fed various dietary levels of inorganic tin and zinc

Three studies were conducted to determine the effects of various dietary levels of tin (less than 1, approximately 100, approximately 200, approximately 500, approximately 2000 micrograms/g diet) and of zinc (approximately 15, approximately 30, approximately 52 micrograms/g diet) on the metabolism of tin, copper, iron and calcium by growing rats. The accumulation of tin in the kidneys and tibias of animals was proportional to dietary exposure. The concentration of tin in the bones of rats fed greater than 100 micrograms Sn/g diet was 5-fold and 20-fold greater than the levels found in kidney and liver, respectively. Rats fed greater than 500 micrograms Sn/g diet had plasma copper levels that were only 13% of control levels and had depressed copper levels in livers and kidneys. The activity of delta-aminolevulinic acid dehydratase in the erythrocytes of rats fed the highest level of tin was 55% of that found in control animals. The amounts, but not the concentrations, of calcium in the tibias of rats fed greater than 100 micrograms Sn/g diet were less than the levels in the bones of control animals. The moderate variations in dietary zinc levels did not affect significantly the levels of minerals in tissues.     

抽动障碍儿童血清锌、铁、铅、铜、镁、钙含量的Meta分析

目的 探究抽动障碍儿童血清微量元素含量与正常健康儿童的差异,为抽动障碍的防治提供参考.方法检索中国知网数据库(CNKI)、重庆维普中文科技期刊数据库(VIP)、万方数据库(Wanfang Data)、临床试验注册中心、Pubmed、Embase、Cochrane Library及Web of Science等数据库,检...     

蒸发浓缩-火焰原子吸收光谱法测定水中铁、锰、铜、锌、铅、镉

目的:利用蒸发浓缩同时测定水中多种重金属,以提高分析速度,节省试剂。方法:采用蒸发浓缩-火焰原子吸收光谱法测定水中铁、锰、铜、锌、铅、镉。结果:可有效扩大直接吸入-火焰原子吸收光谱法的测量范围,能充分满足低浓度地表水、地下水以及其它水样的检测。     

Cadmium,copper, and zinc in rice produced in Java

Cadmium (Cd), copper (Cu) and zinc (Zn) contents in 116 polished and unpolished rice samples produced in the Java Islands of Indonesia were assessed as a base-line study of trace metals. Arithmetic means and one standard deviation were 0.040±0.042 ppm Cd, 2.93±1.11 ppm Cu, and 18.17±3.13 ppm Zn. Concentration ratio of Cd to Zn was 0.00220±0.00222. The correlation coefficients between the metals were low. The two highest samples of rice contained 0.27 and 0.34 ppm Cd. Using the fact that Indonesians consume about 300 g of rice, the daily intake of Cd would exceed the tolerable limit proposed by FAO/WHO and could cause slight chronic renal damage to the rice eaters. Soil type by suborder and rice variety gave little difference of the three metals content in rice. Rice samples from West Java, where major soil type by order is Ultisol, contained higher cadmium and zinc, and lower copper than those from East Java (Vertisol).     

Cadmium,copper, lead and zinc in bovine hair in the new lead belt of missouri

Summary The levels of Cd, Cu, Pb and Zn were determined in washed hair samples from four test cows exposed to multiple lead production sources of contamination and four control cows that were not exposed. Cadmium and lead were found in significantly higher concentrations in the hair collected from the test cows than in the hair of the control cows. The mean concentration of Cd in the summer sample from the test cows' hair was approximately 16 times higher than that of the control cows, and the Pb concentration in hair of the test cows was approximately 75 times higher than that of the control cows. The hair concentrations of Cd, Pb and Zn were significantly affected by season and Cu and Zn concentrations varied significantly among the cows on each farm. There was no relationship between hair and milk lead concentrations. Reduction in lead exposure was reflected more rapidly in blood than in hair concentrations. These results demonstrate the value of using bovine hair samples in surveillance of environmental contamination, as well as other ecologic, epidemiologic and mineral metabolism research.This work was supported by contract 68-02-0092 from the Environmental Protection Agency.