某蓄电池生产地区6～12岁儿童环境铅暴露的调查

目的了解某蓄电池生产地区(A、B、C、D四个村)6～12岁儿童铅暴露状况。方法于2007年10至11月在某蓄电池生产地区(A、B、C、D村)采用分层随机抽样的方法,并采用自制问卷调查当地309名6～12岁儿童,并采集静脉血、头发、指甲样品,采用石墨炉原子吸收光谱法检测血铅、发铅、甲铅含量。结果被调查儿童血铅几何均值为71.2μg/L, 54名儿童血铅≥100μg/L(铅超标率为17.5%)。男女儿童血铅几何均值分别为75.0μg/L、67.5μg/L。A村6～10岁儿童血铅水平高于11～12岁儿童,B村男童血铅水平、铅超标率高于女童。A村(与D村比较)、6～10岁(与11～12岁比较)、男孩(与女孩比较)为儿童血铅超标危险因素,OR值分别为9.110、2.484、2.102。发铅、甲铅含量与血铅浓度均为正相关,男童发铅水平高于女童。结论A村儿童铅暴露最严重;发铅受性别影响;发铅、甲铅可作为铅中毒辅助诊断指标,对铅暴露有提示作用。     

非铅污染地区血铅与发铅水平及相关性分析

目的 研究某非铅污染地区人群中血铅与发铅总体平均水平及两者的相关性.方法 以某非铅污染区域中9个自然村270名健康人群为研究对象,用石墨炉原子吸收光谱法测定其血铅和发铅水平.结果 非铅污染区域人群血铅、发铅水平中位数(M)分别为0.067 μmol/L、3.6μg/g,男性血铅水平高于女性(M分别为0.088、0.050 μmol/L,P＜0.001),女性发铅水平高于男性(M分别为4.0、3.4 μg/g,P＜0.05);人群血铅、发铅水平总体均数的95％可信区间分别为(5.5,7.8)、(3.3,4.1),男性的为(7.3,10.3)、(2.8,4.0),女性的为(2.4,6.0)、(3.4,4.7).血铅水平与发铅水平的spearman等级相关系数为-0.043.结论 非铅污染环境下人群的血铅和发铅总体平均水平都较低,血铅水平与发铅水平无相关性.     

广州市荔湾区产妇及新生儿脐带血铅水平及其影响因素分析

目的了解广州市荔湾区产妇及新生儿脐带血铅水平及其相关的影响因素。方法于2005年7-12月对在某医院产科分娩的155例产妇及其新生儿进行静脉血和脐带血铅含量的测定,并进行家庭社会环境和健康状况问卷调查,分析脐带血铅水平的影响因素。血铅测定采用石墨炉原子吸收光谱法。结果155例母子血铅水平分别为(72.3±47.5)μg/L(8～260μg/L)及(68.7±45.6)μg/L(11～160μg/L)。产妇血铅与新生儿脐血铅含量呈显著性相关(r=0.532 0,P<0.01)。其中,母血铅值≥100μg/L者38例,占24.52%;新生儿脐血铅值≥100μg/L者32例,占20.65%。孕期被动吸烟、居住地靠马路边、住房新装修、怀孕前半年内或怀孕期间染过发是胎儿期铅暴露的危险因素,母亲文化程度及家庭人均收入相对高、了解铅污染相关知识、补钙和补锌是胎儿期铅暴露的保护因素。结论该次调查新生儿脐带血铅水平与家庭和环境因素有关,对孕妇加强宣教,避免影响因素,适时补钙、锌可预防新生儿铅暴露。     

某蓄电池厂作业工人血铅、尿铅与指甲铅检测结果分析

目的 通过对某蓄电池厂工作人员血铅、尿铅及指甲铅水平的分析, 探讨三者在职业病诊断中的价值。
方法 留取该企业203名作业工人静脉血标本、尿标本以及指甲标本, 用石墨炉原子吸收光谱法测定血铅、尿铅以及指甲铅水平, 并对数据进行统计学分析。
结果 该企业铅烟时间加权平均浓度(C_TWA)为(0.31 ±0.37) mg/m3, 铅尘C_TWA为(0.28 ±0.50) mg/m3。员工血铅均值为(280.37 ±164.86)μg/L, 异常率为22.7%;尿铅均值为(0.035 ±0.042) mg/L, 异常率为11.3%;指甲铅均值为(1 407.96 ±2 625.26)μg/g。男性工人血铅、尿铅、指甲铅水平均高于女性工人, 差异有统计学意义(P < 0.01或0.05)。不同工龄组工人血铅、尿铅异常率差异均无统计学意义(P>0.05)。血铅、尿铅水平和指甲铅水平均存在相关关系(r=0.544、0.546, P < 0.01)。
结论 该蓄电池厂铅作业工人血铅、尿铅、指甲铅均有异常, 指甲铅和血铅水平有较好的相关性。指甲铅水平可作为职业性慢性铅中毒诊断的一个辅助指标, 值得进一步探讨。
     

辽宁省一般人群血和尿中铅水平研究

目的调查辽宁省一般人群血和尿中铅水平,分析其分布特点。方法采用整群随机抽样方法,2009—2010年在辽宁省东部、西部和中部抽取2105名6~60岁人群为调查对象,分别采集血液和尿液样品,应用电感耦合等离子体质谱法检测血和尿液中铅水平,并分析年龄、性别和区域对血和尿中铅水平的影响。结果辽宁省一般人群全血中铅的几何均数为29.04μg/L,男性和女性分别为35.11、24.33μg/L(Z=-18.5,P0.01),东、中、西部人群分别为30.59、27.27和29.43μg/L(χ2=21.58,P0.01),吸烟和不吸烟人群分别为42.28、27.46μg/L(Z=-11.52,P0.01),饮酒和不饮酒人群分别为40.39、27.89μg/L(Z=-8.82,P0.01);一般人群尿铅的几何均数为3.22μg/L,男性和女性分别为3.37、3.08μg/L(Z=-1.96,P=0.05);东、中、西部人群分别为3.21、2.22和4.74μg/L(χ2=297.71,P0.01)。结论辽宁省一般人群血铅和尿铅水平存在性别及地区差异,并与吸烟和饮酒有关。     

职业性铅暴露对工人铁代谢的影响

目的分析探讨职业性铅暴露对作业工人铁代谢的影响。方法选取铅暴露工人,采集血尿测定铅负荷和铁代谢指标;分析铅负荷与铁代谢之间的相关性。结果 729名研究对象血铅为(344.28±156.54)μg/L,尿铅为52.64(12.00,72.00)μg/L,锌原卟啉(ZPP)水平为8.56(3.00,10.20)μg/g Hb。各组铁代谢相关指标均值在正常范围内,相关性分析和偏相关分析发现工人血清铁、血清铁蛋白、转铁蛋白、转铁蛋白饱和度和血红蛋白等与血铅和(或)尿铅和(或)ZPP呈负相关(P<0.05)。结论铅暴露作业工人机体铁代谢受到影响。     

钙硒联合对铅暴露小鼠学习记忆能力影响

目的 探讨钙硒2种营养素联合应用对铅暴露小鼠学习记忆能力的影响.方法 3周龄清洁级昆明小鼠36只,随机分为3组:对照组,铅染毒组.钙硒联合干预组;在实验第20 d进行水迷宫实验,取小鼠的血、脑测定铅含量及NO含量、一氧化氮合酶(NOS)和诱导型一氧化氮合酶(iNOS)活性.结果 小鼠钙硒联合干预组血铅(469.59±58.31)μg/L和脑铅(0.460±0.034)μg/g含量高于对照组,低于铅染毒(885.02±105.77)μg/L和(1.290±0.270)μg/g组,差异有统计学意义(P<0.01);钙硒联合干预组脑NO含量为(8.29±1.22)μmol/g、NOS和iNOS活性分别为(4.39±0.98),(1.65±0.28),均低于对照组(10.27±2.27)ixmoVg,(6.22±1.25),(1.91±0.44)高于铅染毒组(5.66±1.04)μmol/g,(2.66±0.59),(0.67±0.14)差异有统计学意义(P<0.01);对照组、钙硒联合干预组小鼠水迷宫逃避潜伏期分别为(43.8±8.9),(44.1±11.7)s,短于铅染毒组的(85.9±23.5)s,差异有统计学意义(P<0.01),钙硒联合干预组与对照组差异无统计学意义.结论 钙和硒联合应用能有效地促进铅模型小鼠拮抗体内铅的毒性作用.     

铅暴露对发育期小鼠学习记忆能力影响

目的 探讨不同铅暴露水平对发育期小鼠学习记忆能力的影响及脑一氧化氮(NO)、总一氧化氮合酶(NOS)与小鼠学习记忆能力的关系.方法 采用自由饮水(含醋酸铅)的方式对刚断乳小鼠染毒,染毒剂量为0.3,1和3 g/L,每组30只.开始染铅记为第0 d,分别在第7,14,21 d进行血铅、小鼠Morris水迷宫试验及小鼠脑铅浓度、脑NO含量和脑总NOS活性的测定.结果 与正常对照组比较,染毒组小鼠血铅和脑铅浓度增加(P＜0.05);迷宫实验中,第21 d,正常组及染铅0.3,1,3 g/L组平均潜伏期分别为(33.8±7.8),(73.0±12.1),(85.9±12.7),(101.3±19.7)s,各铅暴露组与对照组之间差异有统计学意义(P＜0.05);正常组,0.3,1,3 g/L组脑NO含量分别为(10.27±4.28),(6.07±1.95),(5.63±2.03)和(3.74±1.89)μmol/(g·prot),各铅暴露组与对照组之间的差异有统计学意义(P＜0.05);正常组,0.3,1,3 g/L组脑总NOS活性分别为(6.22±2.42),(4.36±1.76),(2.84±1.42)和(3.25±1.76)U/(mg·prot),各铅暴露组与对照组之间差异有统计学意义(P＜0.05);第21 d,小鼠脑NO含量和脑总NOS与血铅、脑铅浓度及Morris水迷宫逃避潜伏期均呈负相关(r=-0.540,P=0.000;r=-0.520,P=0.000;r=0.755,P=0.000;r=0.709,P=0.000).结论 铅暴露对发育期小鼠学习记忆能力的影响与铅暴露导致的脑NOS活性降低和NO含量减少密切相关,且影响程度与铅的暴露时间及浓度有关.     

铅接触对工人血清骨钙素水平的影响

目的研究铅接触对工人血清骨钙素(BGP)的影响。方法对某蓄电池厂73名铅作业工人及当地某机械厂73名非铅接触者进行血铅、尿铅、血清BGP水平的测定。结果铅作业工人血铅、尿铅水平显著高于对照组(P<0.01);铅接触组的血清BGP质量浓度(4.75±3.28)μg/L,显著低于对照组(7.91±3.56)μg/L(P<0.01);血清BGP与血铅水平有显著负相关(P<0.01),而与尿铅相关性无统计学意义(P>0.05);随接铅工龄的延长,BGP水平逐渐降低(P<0.01)。结论铅接触可引起工人血清BGP水平降低,提示铅可能引起成骨细胞的代谢异常。     

电子垃圾处理环境中居民体内重金属水平及其影响因素的研究

目的 分析暴露于电子垃圾处理环境的人群重金属内暴露水平及其影响因素.方法 于2005年8-12月在我国南方某有十余年历史的电子垃圾集散地及无明显工业污染的农业区随机选取调查对象各59名(暴露组)和79名(对照组).用原子吸收光谱法测定研究对象血和尿中铅、镉、铜水平,并分析研究对象体内的重金属水平及其相关影响因素.结果 暴露组和对照组人群血铅、血镉及尿铅的差异均无统计学意义.但暴露组的尿铜水平(中位数:38.06 μg/g Cr)却高于对照组(中位数:23.69μg/g Cr),差异有统计学意义(P＜0.01);而对照组血清铜水平(中位数:0.86 mg/L)和尿镉水平(中位数:1.96 μg/g Cr)则高于暴露组(血清铜中位数:0.76 mg/L;尿镉中位数:1.04 μg/g Cr),差异均有统计学意义(P＜0.01).此外,电子垃圾回收拆解从业史是血铅的危险因素(OR=3.2,P＜0.05),性别和吸烟是血镉升高的危险因素(性别:OR=7.4,P＜0.05;吸烟:OR=18.4,P＜0.05).结论 电子垃圾处理环境中的铜污染可能危及当地居民健康.对照区未知的镉和铜潜在污染源暴露可能与当地居民尿镉和血清铜水平有关.     

109Cd K x ray fluorescence measurements of tibial lead content in young adults exposed to lead in early childhood

OBJECTIVES—Tibia lead measurements were performed in a population of 19-29 year old people who had been highly exposed to lead in childhood to find whether lead had persisted in the bone matrix until adulthood.
METHODS—¹⁰⁹Cd K x ray fluorescence was used to measure the tibia lead concentrations of 262 exposed subjects and 268 age and sex matched controls. Questionnaire data allowed a years of residence index to be calculated for exposed subjects. A cumulative blood lead index was calculated from the time weighted integration of available data of blood lead.
RESULTS—The mean (SEM) difference between exposed and control men was 4.51 (0.35) µg Pb/g bone mineral, and between exposed and control women was 3.94 (0.61) µg Pb/g bone mineral. Grouped mean bone lead concentrations of exposed subjects were predicted best by age. When exposed and control subjects' data were combined, grouped mean bone lead concentrations were predicted best by cumulative blood lead index. The years of residence index was neither a good predictor of bone lead concentrations for exposed subjects nor for exposed and control subjects combined. Finally, exposed subjects had increased current blood lead concentrations that correlated significantly with bone lead values.
CONCLUSION—Bone lead concentrations of exposed subjects were significantly increased compared with those of control subjects. Lead from exposure in early childhood had persisted in the bone matrix until adulthood. Exposed subjects had increased blood lead concentrations compared with controls. Some of this exposure could be related to ongoing exposure. However, some of the increase in blood lead concentration in adult exposed subjects seemed to be a result of endogenous exposure from increased bone lead stores. The endogenous exposure relation found for men was consistent with reported data, but the relation found for women was significantly lower. Further research is needed to find whether the observed differences are due to sex, or pregnancy and lactation.


Keywords: lead; environment; childhood     

Windblown Lead Carbonate as the Main Source of Lead in Blood of Children from a Seaside Community: An Example of Local Birds as “Canaries in the Mine”

Background

In late 2006, the seaside community in Esperance, Western Australia, was alerted to thousands of native bird species dying. The source of the lead was thought to derive from the handling of Pb carbonate concentrate from the Magellan mine through the port of Esperance, begun in July 2005. Concern was expressed for the impact of this process on the community.

Objective

This study was designed to evaluate the source of Pb in blood of a random sample of the community using Pb isotope ratios.

Methods

The cohort comprised 49 children (48 < 5 years of age) along with 18 adults (> 20 years of age) with a bias toward higher blood lead (PbB) values to facilitate source identification.

Results

Mean PbB level of the children was 7.5 μg/dL (range, 1.5–25.7 μg/dL; n = 49; geometric mean, 6.6 μg/dL), with four children whose PbB was > 12 μg/dL. The isotopic data for blood samples lay around two distinct arrays. The blood of all children analyzed for Pb isotopes contained a contribution of Pb from the Magellan mine, which for young children ranged from 27% up to 93% (mean, 64%; median, 71%). Subtraction of the ore component gave a mean background PbB of 2.3 μg/dL. Several children whose PbB was > 9 μg/dL and most of the older subjects have complex sources of Pb.

Conclusions

The death of the birds acted as a sentinel event; otherwise, the exposure of the community, arising from such a toxic form of Pb, could have been tragic. Isotopic data and mineralogic and particle size analyses indicate that, apart from the recognized pathway of Pb exposure by hand-to-mouth activity in children, the inhalation pathway could have been a significant contributor to PbB for some of the very young children and in some parents.     

电子垃圾拆解集散地居民铅、镉、铜内暴露水平与淋巴细胞双微核率的关系

[目的]研究电子垃圾拆解集散地居民血尿铅、镉、铜的暴露水平和淋巴细胞双微核率的变化及其影响因素。[方法]选择某电子垃圾拆解集散地居民58人为暴露组（男性44人，女性14人），平均年龄为33．0岁；距离集散地50km，且无明显工业污染的农业区人群80人为对照组（男性41名，女性39名），平均年龄为43．7岁。采用石墨炉原子吸收光谱法检测血铅、血镉和尿铅、尿镉、尿铜含量，火焰原子吸收光谱法测定血清铜含量；胞质阻滞双微核实验测定淋巴细胞双微核率。[结果]暴露组居民血铅和尿铜中位数分别为0．52μmol／L和51．97μmol／mmol肌酐，均高于对照组（P〈0．05）。暴露组人群双微核率中位数（4‰）是对照组（1‰）的4倍，年龄是血镉增高的危险因素（OR=1．1，P〈0．01）；电子垃圾拆解职业暴露史是影响血铅水平及双微核率的危险因素（OR=2．9，P〈0．05；OR=6．7，P〈0．01）。[结论]电子垃圾拆解地居民血铅、尿铜水平及淋巴细胞双微核率均高于对照区居民。     

1989-2009年中国九省区居民膳食营养素摄入状况及变化趋势(二)18-49岁成年居民膳食能量摄入状况及变化趋势

目的分析九省区18-49岁居民能量摄入状况及其变化趋势,为中国居民能量参考摄入量修订和相应的膳食指导提供依据。方法以"中国健康与营养调查"项目1989-2009年间8次调查中有膳食调查资料的18-49岁调查对象作为研究对象。使用SAS9.2软件对数据库资料进行统计分析。结果 2009年九省区18-49岁男女性成年居民的能量摄入[kJ/d(kcal/d)]分别为10277.6(2456.4)和8539.1(2040.9)。其中城市、郊区、县城和农村男性成年居民的能量摄入[kJ/d(kcal/d)]分别为9707.3(2320.1),10022.8(2395.5),9876.3(2360.5)和10632.8(2541.3);女性分别为7923.7(1893.8),8120.7(1940.9),8340.0(1993.3)和8909.0(2129.3)。能量的食物来源以谷类食物为主,尤其是农村成年居民,约占总能量的57.7%。蛋白质、脂肪和碳水化合物供能比分别为15.1%、31.4%和53.5%。其中,城市、郊区、县城和农村成年居民的脂肪供能比分别为36.0%、33.7%、32.19%和29.2%,1989-2009年我国成年居民能量摄入呈现出总体下降的趋势,能量摄入从高到低依次为农村、郊区、县城、城市,以郊区降低最明显,20年间减少1966.1 kJ/d(469.9 kcal/d)。结论 2009年我国九省区18-49岁成年居民能量摄入较前有较大幅度减少,脂肪供能比显著增加,使肥胖及膳食相关慢性病的高危人群增加。其原因可能在于动物性食物和食用油摄入的增加,值得重点关注。在修订能量参考摄入量和制订膳食指导原则时,应充分考虑我国的经济发展水平及不同地区的人群膳食消费特点。     

辽宁省1991—2006年成人超重流行趋势分析

目的分析1991—2006年辽宁省成年居民超重状况及变化趋势。方法以1991、1993、2000、2004和2006年中国健康与营养调查资料中健康成人为对象,以BMI≥24 kg/m2作为成人超重判定标准;应用SAS 8.2软件进行统计分析。结果 1991—2006年辽宁省成年居民超重率呈逐年增长趋势,超重率由1991年的24.4%增加到2006年的48.8%,15年间增长幅度达到100%,且超重增长速度逐年加快。男性超重率增长幅度明显高于女性,至2006年男女性超重率分别为46.8%和50.6%,性别差异逐渐消失。18～30岁男女性是超重率增长最快年龄段。男性居民中,城市居民超重率增长最快,2006年已达到62.5%。女性居民中,农村居民超重率增长最快,至2006年4类地区女性超重率差异基本消失。结论 1991—2006年辽宁省成年居民超重率呈明显上升趋势,15年间超重率增加一倍。     

Efficient antioxidant capacity against lipid peroxide levels in healthy elderly of Mexico City

We evaluated antioxidant activity against lipid peroxide levels (LPO) in healthy elderly and adults of Mexico City in comparison with a population of a rural area. The study included free-living subjects: 38 adults aged <60 years and 129 older subjects aged > or = 60 years of urban Mexico City in addition to 37 adults aged <60 years and 88 older subjects aged > or = 60 years of rural area (Actopan, Hidalgo State, Mexico). LPO were observed as higher in adults and elderly of the urban area than among rural subjects (P<0.01), although LPO levels were similar in rural adults and elderly (P>0.05); conversely, in urban area levels were higher in the elderly than in adults (P<0.01). On the other hand, the superoxide dismutase in urban elderly was higher than that in rural elderly (P<0.05) but similar between urban adults and urban elderly (P>0.05). Total oxidant status in urban elderly was higher than that in rural elderly (P<0.01). Our findings allow us to conclude that the urban elderly (residents of Mexico City) have higher oxidative stress than the rural-dwelling elderly, though the urban elderly have efficient antioxidant capacity as a response to elevated LPO.     

Lead and cadmium levels and balance and vestibular dysfunction among adult participants in the National Health and Nutrition Examination Survey (NHANES) 1999-2004

Background: Few studies have been conducted to identify risk factors for balance and vestibular dysfunction in general populations, but previous studies have reported evidence of adverse effects of lead and cadmium on balance control in high-risk groups.Objective: We evaluated the relationship between blood lead and cadmium levels and balance and vestibular dysfunction in a general population study.Methods: We analyzed data from the 1999–2004 National Health and Nutrition Examination Survey (NHANES) of 5,574 adults ≥ 40 years of age. Balance dysfunction was evaluated by the Romberg Test of Standing Balance on Firm and Compliant Support Surfaces, which examines the ability to stand unassisted using four test conditions to evaluate vestibular system, vision, and proprioception inputs that contribute to balance. Blood levels of lead and cadmium were measured by atomic absorption spectrometry. Associations were estimated using logistic regression models adjusted for potential confounders. Associations with time to loss of balance were estimated using adjusted Cox proportional hazard models.Results: The adjusted odds ratio (OR) for balance dysfunction in association with the highest quintile (3.3–48 µg/dL) versus the lowest quintile (< 1.2 µg/dL) of lead was 1.42 [95% confidence interval (CI): 1.07, 1.89]. The corresponding OR for cadmium (0.9–7.4 µg/L vs. < 0.2 µg/L) was 1.27 (95% CI: 1.01, 1.60). The adjusted hazard ratio for time to failure for the most physiologically challenging balance test among subjects with the highest vs. lowest quintiles of blood lead was 1.24 (95% CI: 1.04, 1.48). Cadmium levels were not associated with time to failure.Conclusions: Our findings suggest that blood lead and cadmium levels may be associated with balance and vestibular dysfunction in a general sample of U.S. adults.     

鞍山市儿童血铅水平状况调查

目的了解鞍山市3~6岁儿童铅中毒情况并探讨血铅水平与不同地区、年龄、性别的关系。方法采用分层整群抽样法,抽取鞍山市5所托幼机构的3~6岁408名学龄前儿童（男孩217名,女孩192名）,用石墨炉法测定血铅,并对其父母进行相关知识问卷调查。结果鞍山市不同地区幼儿园间儿童血铅水平差异有统计学意义（P〈0.05）。男孩与女孩在同年龄组间血铅水平差异无统计学意义（P〉0.05）,但不同年龄组男孩的血铅水平差异有统计学意义（P〈0.01）。结论目前鞍山市儿童铅中毒问题比较严重,应采取行之有效的干预措施。     

锌原卟啉作为环境铅污染人群筛查指标的可行性研究

目的探讨红细胞锌原卟啉（ZPP）应用于人群接触环境铅污染筛查指标的可行性。方法以紫金县某电池厂附近常住居民为调查对象,采集被调查者静脉血2～3 mL,采用血液锌原卟啉测定仪测定ZPP、石墨炉原子吸收光谱法测定血铅。儿童以血铅含量≥100μg/L、成年人以≥400μg/L为慢性铅中毒判定标准。结果共调查946名居民,其中1～13岁儿童174人、16～87岁成年人772人。儿童血铅含量超标率为14.9%（26/174）,儿童ZPP含量中位数为0.780μmol/L,血铅中位数为47.675μg/L,儿童ZPP含量与血铅含量的相关关系没有统计学意义（P〉0.05）。成人血铅含量超标率为9.5%（73/772）,成人ZPP含量中位数为0.740μmol/L,血铅中位数为69.572μg/L,成人ZPP含量与血铅含量呈弱相关关系（r=0.344,P〈0.05）。儿童血铅高水平组（血铅≥100μg/L）ZPP含量与血铅含量呈较强的相关关系（r=0.530,P〈0.05）,儿童血铅低水平组（血铅〈100μg/L）ZPP含量与血铅含量的相关关系没有统计学意义（P〉0.05）。成人血铅高水平组（血铅≥400μg/L）和低水平组（血铅〈400μg/L）的ZPP含量与血铅含量均具有相关关系（r分别为0.566、0.142,均P〈0.05）。结论成人血铅或儿童血铅水平较高时,ZPP可以作为环境铅污染人群筛查的指标。     

Lactose intolerance in Iran.

One hundred five Iranian subjects, ranging in age from 4 months to 25 years, were tested for lactose absorption and tolerance. After ingesting a lactose dose, on the basis of low blood glucose response, 68% of the subjects were malabsorbers. Prevalence of lactose malabsorption increased with age, i.e., 31% of the children less than 3 years of age malabsorbed lactose, whereas 86% of adults did so. Clinical manifestations of lactose intolerance were shown by 39% of all subjects; of those who were lactose malabsorbers, only 57% manifested clinical symptoms. Among the lactose malabsorbers, the lowest prevalence of clinical symptoms occurred among the children less than 3 years of age and the highest in adults.