环境铅与幼儿体内铅水平及健康危害研究

目的　了解环境铅与幼儿体内铅水平及对幼儿体格发育的影响。方法　测定大气、食品、饮水等铅含量以及5 0 1例 3～ 6岁儿童发铅和血铅含量 ,并检查 2 6 4名儿童的体格发育情况。结果　计算获得市区幼儿每人每日摄入铅约 5 4 μg ,郊区约 4 5 μg ,市区和郊区幼儿发铅分别是 18 71± 8 8μg/g和 13 97± 8 0 μg/ g:血铅分别是 131 2± 72 1μg/L和 10 8 3± 6 8 1μg/L(1μg/L =0 0 0 4 83μmol/L) ;市区幼儿的发铅和血铅水平显著高于郊区 ,P <0 0 0 1;市区幼儿血铅≥ 10 0 μg/L者占 6 9 8% ,郊区占 4 0 1% ;以血铅 10 0 μg/L划线分组比较幼儿体格发育 ,各年龄段幼儿血铅 <10 0μg/L和≥ 10 0 μg/L组的身高、体重、胸围、头围和血色素含量无显著性差异。 结论　成都市环境铅污染严重 ,幼儿血铅水平及铅中毒流行率较高 ,应重视防治儿童铅中毒。     

二巯基丁二酸和钙、维生素C联合应用对铅中毒小鼠体内铅水平的影响

目的探讨低剂量二巯基丁二酸(DMSA)与营养素联合应用治疗铅中毒的效果。方法实验组小鼠饮用0·1%的醋酸铅溶液6周后,随机分为单纯染铅组、低剂量DMSA组(50mg/kg)、高剂量DMSA组(100mg/kg)及低剂量DMSA与钙、维生素C联合组;干预治疗3周后,检测小鼠血、股骨、肝、肾和脑的铅含量。结果低剂量DMSA、钙和维生素C联合组小鼠血、股骨、肝、肾和脑的平均铅水平分别为241·4μg/L、270·31、0·46、3·66、0·53μg/g,其中血和肝脏的铅水平与低剂量DMSA组(分别为323·7μg/L,0·86μg/g)相比差异有显著性(P<0·01),且该组血铅水平与高剂量DMSA组血铅(288·0μg/L)相比差异也有显著性(P<0·05)。结论DMSA、钙、维生素C联合应用既减少药物的使用剂量,又能保证较好的驱铅治疗效果。     

急性四乙基铅中毒患者血铅和尿铅含量与中毒程度的关系

目的观察血铅和尿铅含量与急性四乙基铅中毒程度之间的关系。方法分别用微分电位溶出法测定31名四乙基铅接触者的血铅和尿铅并对其进行统计学分析。结果①重度中毒组血铅为(3.78±1.21)μmol/L,尿铅为(1.34±0.52)μmol/L;轻度中毒组血铅为(2.58±1.09)μmol/L,尿铅为(0.86±0.34)μmol/L。其结果与四乙基铅接触组比较,差异均有显著性(P<0.05);②血铅与尿铅测定结果呈正相关,相关系数为0.261 8。结论脱离接触四乙基铅早期测定血铅、尿铅水平可作为评判四乙基铅中毒轻重程度的一项参考指标。     

药食两用中药预防性驱铅效果研究

[目的]研究药食两用中药预防性驱铅效果。[方法]将66名血铅高于2.40μmol/L的铅接触工人 ,随机分为对照组和试验组 ;测定两组分别服用安慰剂和中药前后的血铅、尿铅含量以及红细胞中游离锌卟啉 (ZPP) ,同时 ,检查血、尿常规、肝肾功能等指标。[结果]服用中药前试验组和对照组之间血铅、尿铅无差异。服用中药后 ,试验组血铅[15d为(4.63±2.23) μmol/L,30d为 (3.28±1.55) μmol/L]明显低于服用中药前[(8.02±1.23) μmol/L] ;试验组尿铅[15d为(1.24±0.61) μmol/L,30d为 (0.88±0.33) μmol/L]明显高于服用中药前[(0.63±0.40) μmol/L] ,差异均有统计学意义 ,而对照组服用安慰剂前后血铅、尿铅无差异。服用中药前后试验和对照组血ZPP无差异 ,服用中药15、30d后 ,血ZPP[15d为 (20.05±11.5) μg/gHb,30d为 (18.30±11.3) μg/gHb]明显低于用药前[(25.24±20.2) μg/gHb,P<0.05]。服用中药前后血、尿常规、肝肾功能等指标无差异。[结论]本研究选用的药食两用中药具有一定的驱铅作用 ,同时不改变机体的其他生理功能。     

环境铅暴露的新婚女性血铅水平与受孕时间的队列研究

目的研究环境铅暴露的新婚女性血铅水平对临床受孕时间(TTP)的影响。方法用前瞻性队列研究方法,对有环境铅暴露的准备怀孕的210对新婚夫妇建立研究队列,进行基线调查,采集静脉血进行血铅测定,并追踪至临床怀孕,计算TTP,分析血铅水平对TTP的影响。结果210例女性血铅几何均值±标准差为(62.71±2.18)μg/L,平均TTP为2.95个月经周期,随着TTP的延长,受孕率逐渐降低;女性高血铅组(≥100μg/L)和低血铅组(<100μg/L)TTP中位数分别为3.38、2.74个月经周期,TTP分布构成比差异有统计学意义(P<0.05);COX比例风险模型进行多元逐步回归分析显示,女性高、低血铅组受孕力比值(FR)为0.626(95%可信区间0.416～0.941),差异有统计学意义(P<0.05),表明女性血铅≥100μg/L时,受孕力可能下降。结论环境铅暴露对TTP可能有不良影响。     

杭白菊复合饮驱铅效果评价

目的了解杭白菊复合饮驱铅效果。方法采用小鼠铅负荷增高实验,建立中毒模型。测定各组血铅、骨铅、维生素C指标;另选择血铅高于2.40μmol/L接铅者60名,随机分为试验组与对照组,测定服用杭白菊复合饮前后血铅、尿铅指标。结果驱铅实验组小鼠血铅、骨铅均低于染毒组,差异均有统计学意义（P〈0.05）。维生素C含量显著增高（P〈0.01）,杭白菊复合饮对小鼠血铅、骨铅的铅清除率分别为36.7%,33.4%;接铅者试食杭白菊复合饮服用15 d后与服用前比较血铅下降明显,差异有统计学意义（P〈0.01）,服用30 d后下降更明显。服用15和30 d后血铅的铅清除率分别为42%,59%。服用15 d后尿铅平均值明显增高,是服用前的2倍,差异有统计学意义（P〈0.01）。服用30 d后尿铅排出下降,但与试验前比较差异有统计学意义（P〈0.05）。结论杭白菊复合饮驱铅效果满意。     

职业性铅作业工人神经行为及记忆力研究

目的探讨铅对作业工人神经行为功能及记忆力的影响。方法采用完全随机的原则,抽取工龄大于1 a的铅作业工人,测试其对声音、光刺激反应时间;背诵数得分、译码得分,然后按照测试工人的血铅水平分为3组:A组(200μg/L)、B组(200~399μg/L)和C组(≥400μg/L)。对测定结果进行统计分析。结果 A组对声音、光刺激反应、背诵数得分分别为406.38±24.40、389.18±20.64、3.05±0.23,B组分别为380.00±11.53、350.47±11.93、3.12±0.21,C组分别为392.25±23.59、360.65±19.52、2.90±0.30;3组间的差异无统计学意义。A组的译码得分为30.59±3.55,B组为18.83±1.45,C组为16.50±2.12;A组与B组、C组的差异有统计学意义,B组、C组间差别无统计学意义。结论铅作业满1 a者,血铅≥200μg/L者,临床尚没有明显症状时,其神经行为协调能力没有明显减退,但记忆力减弱,智力水平下降。显示铅对智力有一定影响。     

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。     

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。
     

广东江门地区3月龄婴儿血铅与乳母血铅及乳铅等因素的相关性研究

目的:了解广东省江门地区3月龄婴儿血铅与乳母血铅、乳铅等的相关关系,寻找影响婴儿血铅水平的高危因素。方法:采用横断面描述性人群调查方法,对2005年1~4月在广东省江门市新会区妇幼保健院出生的纯母乳或者混合喂养的新生儿在3月龄时分别进行婴儿血铅、乳母血铅与乳铅的测定,并结合其出生时脐带血铅水平,综合评价婴儿血铅的相关影响因素。结果:婴儿3月龄时血铅水平(49.53±23.6μg/L)与其对应的脐血铅水平(49.70±23.77μg/L)比较无显著性差异(P>0.05);但是两者均明显低于婴儿3月龄时乳母血铅水平(59.24±28.71μg/L)而高于此时的乳铅水平(26.77±13.70μg/L)(P均<0.05);而乳铅水平也明显低于同时采集的乳母血铅水平(P<0.05)。Spearman偏相关分析显示,婴儿3月龄血铅水平与出生时脐带血铅水平(Spearman偏相关系数rs=0.39,P<0.01)、乳母血铅水平(rs=0.42,P<0.01)以及乳铅水平(rs=0.31,P<0.01)均存在显著的正相关关系。多元回归分析显示,在校正了居住地点、铅接触史、性别等因素的影响后,母乳血铅每变化1μg/L,可相应引起婴儿血铅约14μg/L的变化。结论:乳母血铅及乳铅可明显影响3月龄婴儿血铅水平;乳铅的定量测定和分析,对儿童早期铅暴露的防治具有重要意义。     

Temporal and interindividual variation in erythrocyte zinc-protoporphyrin in lead exposed workers

Nineteen male workers from a factory making lead batteries participated in monthly blood tests to follow the effects of decreasing exposures to lead. The overall average blood lead (B Pb) concentration was 1.95 mumol/l (40 micrograms/100 ml), but a significant decrease was seen over the one year study period. The relation to erythrocyte zinc-protoporphyrin (ZPP) concentration showed considerable scatter and only marginal improvement of the relation was obtained when each ZPP result was compared with the average B Pb concentration during the previous four months. On an individual basis, five men showed a considerable decline in ZPP following decreases in B Pb concentration. In five other subjects with similar decreases in B Pb, no change in ZPP concentration was seen. These two groups were similar with regard to haemoglobin concentration, initial B Pb concentration, and age, but differed in duration of exposure. A longer exposure time and presumably, therefore, larger body burdens of lead seemed to prevent the expected decrease in erythrocyte ZPP.     

Temporal and interindividual variation in erythrocyte zinc-protoporphyrin in lead exposed workers.

Nineteen male workers from a factory making lead batteries participated in monthly blood tests to follow the effects of decreasing exposures to lead. The overall average blood lead (B Pb) concentration was 1.95 mumol/l (40 micrograms/100 ml), but a significant decrease was seen over the one year study period. The relation to erythrocyte zinc-protoporphyrin (ZPP) concentration showed considerable scatter and only marginal improvement of the relation was obtained when each ZPP result was compared with the average B Pb concentration during the previous four months. On an individual basis, five men showed a considerable decline in ZPP following decreases in B Pb concentration. In five other subjects with similar decreases in B Pb, no change in ZPP concentration was seen. These two groups were similar with regard to haemoglobin concentration, initial B Pb concentration, and age, but differed in duration of exposure. A longer exposure time and presumably, therefore, larger body burdens of lead seemed to prevent the expected decrease in erythrocyte ZPP.     

职业性铅接触工人氧化应激及免疫功能状况调查

  目的  探索体内不同浓度的铅负荷对男性工人氧化应激及免疫功能造成的影响。
  方法  以某蓄电池厂工人为研究对象,探讨了血铅与氧化应激及免疫功能的关系。
  结果  共纳入130名蓄电池厂男性作业人员作为研究对象,其中高铅组（血铅> 300 μg/L）34人,中铅组（200 μg/L ≤血铅≤ 300 μg/L）51人,低铅组（血铅值< 200 μg/L）45人。与低铅组比较,中铅组人群的SOD水平升高（P < 0.05）,其余各组之间的MDA、SOD、GSH-Px水平差异均无统计学意义（P > 0.05）。高铅组人群TNF-α水平高于低铅组、中铅组（P < 0.05）;其余各组之间的IgG、IgA、IgM、C3、C4、IL-2水平差异均无统计学意义（P > 0.05）。3组人群中从低铅组到高铅组,ZPP的水平逐渐升高（P < 0.05）。血铅浓度和外周血TNF-α（r_s=0.213,P < 0.05）、ZPP（r_s=0.513,P < 0.01）呈正相关,其余指标与血铅浓度之间无相关性（P > 0.05）。
  结论  随着血铅浓度的升高,铅可能对机体有一定的氧化损伤和免疫损伤倾向。
     

长期饮用纯净水对大鼠脏器及组织铅蓄积的影响

目的观察长期饮用纯净水是否能增加铅在体内的蓄积及毒性。方法将104只断乳雄性SPF级SD大鼠随机分为8组(其中铅染毒组经饮水途径给予醋酸铅),分别为自来水对照组、纯净水对照组、低铅自来水组(含铅50mg/L)、低铅纯净水组(含铅50mg/L)、中铅自来水组(含铅200mg/L)、中铅纯净水组(含铅200mg/L)、高铅自来水组(800mg/L)、高铅纯净水组(含铅800mg/L)。各组食物及其他处理因素完全一致。于第4、6、8、10、24、28周尾静脉采全血动态监测血铅,在28周时处死大鼠取材,采用原子吸收分光-石墨炉法测定血铅及脑、心脏、肝脏、肾脏、骨等实质性脏器及组织的铅含量;以表面荧光法检测血液锌原卟啉(ZPP)含量。结果在相同的铅染毒剂量下,不同的饮水对大鼠血铅的影响未显示统计学意义,但饮用纯净水的大鼠肾脏、心脏、肝脏、脑、骨中的铅含量均高于饮用自来水的大鼠;同时饮用纯净水的大鼠其血液锌原卟啉含量均高于饮用自来水的大鼠,在低剂量铅染毒组间差异有统计学意义(P<0.05)。结论在本研究的染毒剂量下,结果提示长期饮用纯净水能增加铅在大鼠心、肝、肾、脑、骨中的蓄积及其对造血系统的毒性,尤其是在低铅暴露背景下。     

低水平脐血铅浓度与新生儿白细胞DNA端粒长度的相关性研究

目的 研究低水平脐血铅浓度与新生儿白细胞DNA端粒长度的相关性, 为低水平铅暴露对新生儿端粒长度及日后生长发育的影响提供新的客观依据。方法 选择脐血铅浓度低于100 μg/L足月顺产儿97例。以脐血铅浓度50 μg/L为界将其分为两组。A组:脐血铅浓度<50 μg/L, B组:脐血铅浓度≥50 μg/L。采用原子吸收光谱法测定血铅浓度, 实时荧光定量PCR法测白细胞DNA的相对端粒长度。结果 A组68例, B组29例。A组端粒长度为0.803±0.568, B组端粒长度为0.536±0.476, 两组比较差异有统计学意义(t=2.222, P=0.029);端粒长度与血铅浓度呈负相关(r=-0.303, P=0.003)。结论 新生儿白细胞DNA端粒长度与脐血铅浓度相关, 低水平脐血铅亦可致新生儿端粒长度的缩短。     

Lead exposure inhibits fracture healing and is associated with increased chondrogenesis, delay in cartilage mineralization, and a decrease in osteoprogenitor frequency

Lead exposure continues to be a significant public health problem. In addition to acute toxicity, Pb has an extremely long half-life in bone. Individuals with past exposure develop increased blood Pb levels during periods of high bone turnover or resorption. Pb is known to affect osteoblasts, osteoclasts, and chondrocytes and has been associated with osteoporosis. However, its effects on skeletal repair have not been studied. We exposed C57/B6 mice to various concentrations of Pb acetate in their drinking water to achieve environmentally relevant blood Pb levels, measured by atomic absorption. After exposure for 6 weeks, each mouse underwent closed tibia fracture. Radiographs were followed and histologic analysis was performed at 7, 14, and 21 days. In mice exposed to low Pb concentrations, fracture healing was characterized by a delay in bridging cartilage formation, decreased collagen type II and type X expression at 7 days, a 5-fold increase in cartilage formation at day 14 associated with delayed maturation and calcification, and a persistence of cartilage at day 21. Fibrous nonunions at 21 days were prevalent in mice receiving very high Pb exposures. Pb significantly inhibited ex vivo bone nodule formation but had no effect on osteoclasts isolated from Pb-exposed animals. No significant effects on osteoclast number or activity were observed. We conclude that Pb delays fracture healing at environmentally relevant doses and induces fibrous nonunions at higher doses by inhibiting the progression of endochondral ossification.     

An Evaluation of Interferences

A pilot study was initiated to examine cord blood from approximately 300 newborns of various ethnic groups from two New York City hospitals for lead (Pb), erythrocyte protoporphyrin (EP), ferritin (FRT), and hemoglobin (Hb) levels during 1979 and 1980. Results showed an overall mean Pb level of 8 ± 4 μg/dl, EP level of 61 ± 26 μg/dl [geometric mean (GM) = 66.36], FRT level of 165 ± 107 ng/ml (CM = 135.99), and a distribution frequency of Hb with nearly 69% between 13.5 and 16.9 g % (mean ± standard deviation = 15 ± 1), 20% below 13.4 g % (12 ± 2 g %), and 11% at or above 17.0 g % (18 ± 1 g %). Both EP and FRT showed a bimodal distribution. There was a negative correlation between blood EP and plasma FRT levels that was significant at the .03% level. The study also showed that a significant drop in mean cord blood Pb levels occurred compared with earlier studies. Follow up of newborns with mildly elevated Pb and EP levels should be made and screening of mothers for Pb levels during early pregnancy should constitute a part of prenatal care, particularly for those from urban areas with previously demonstrated environmental Pb hazard.     

Serum Calmodulin Activity in Male Lead-exposed Workers

Abstract

Serum calmodulin (CaM) activity was studied in 75 lead exposed and 21 non-exposed male workers. The lead-exposed workers were divided into groups with low blood lead (BPb < 50 μg/dL) and high blood lead (BPb ≥ 50 μg/dL). The concentrations of lead, calcium, magnesium, copper, zinc, and free erythrocytic protoporphyrin (FEP) in blood were determined. Serum samples were heated in a water bath (100° C) for 3 minutes arid centrifuged for 15 minutes at 4° C (18,000 × g). The supernatants obtained were used to measure CaM activity. The results showed that: 1) Average blood lead concentrations in workers with both low and high levels of exposure were significantly higher than those in controls (p < 0.05). 2) Serum CaM activity in the high-exposure group (31.09 ± 7.84 μg/dL) was significantly lower than that in controls (78.11 ± 15.13 μg/dL,p < 0.05). The biological threshold of BPb inhibition of CaM activity was less than 50 μg/dL. 3) Multiple correlation analysis showed a negative dose-response relationship between BPb and CaM activity. The step wise regression procedure indicated that lead had negative, and calcium and magnesium positive, effects on serum CaM activity. The regression equation was Y = 66.1383 – 1.0857 X_l + 2.9676 X₂ + 5.2222 X₃ (Y:CaM; X_l:Pb; X₂: Ca; X₃:Mg). These results of the first such study carried out in male lead-exposed workers suggest that lead can inhibit CaM activity in humans.     

Lead and cadmium absorption among children near a nonferrous metal plant: A follow-up study of a test case

During a first survey (1974) increased lead absorption accompanied by impaired heme biosynthesis was found among children (11 yr) attending schools situated at less than 1 km (subgroup A) and 2.5 km (subgroup B) from a lead smelter.Eighteen months after major improvements had been introduced in the factory to reduce its lead emission, a second survey (1976) was carried out in the same schools (lead smelter and rural area) on other groups of children which were comparable with those of the first survey. The continuous air monitoring revealed for the lead smelter area a considerable decrease in airborne lead. The median values dropped from 3.2 to 1.2 μg Pb/m³ at less than 1 km and from 1.6 to 0.5–0.8 μg Pb/m³ at 1.5 km from the plant; in the rural area it remained unchanged at 0.3 μg Pb/m³.In order to evaluate the efficiency of the technological improvements we assessed the lead and cadmium exposure of the children by measuring lead concentration in blood (PbB) and urine (PbU), erythrocyte δ-aminolevulinic acid dehydratase (ALAD) activity, free erythrocyte porphyrin (FEP) concentration, δ-aminolevulinic acid excretion in urine (ALAU), and cadmium concentration in blood (CdB) and urine (CdU). Subgroups A and B exhibited higher PbB and CdU levels, and lower ALAD activity than the rural group; but PbU, CdB, FEP, and ALAD were significantly increased only in subgroup A. Compared with the results of the first survey, a significant tendency to a normalization of PbB was found at 2.5 km, but at less than 1 km the biological parameters (particularly PbB, ALAD, FEP) did not improve. The PbB percentile distribution in subgroup B lies now under the tentative PbB percentile distribution proposed in the PbB Directive of the Commission of the European Communities (CEC): that of subgroup A, however, is still above that of the CEC proposal. Taking into account the higher degree of vulnerability to lead exposure as compared to adults a more restrictive PbB percentile distribution has been proposed for children.Two hypotheses have been put forward to explain the lack of significant improvements in the biological parameters of the children living at less than 1 km from the lead smelter. Ingestion of dust and dirt (probably due to hand contamination) from their surroundings in the course of their normal everyday activity may represent, in addition to air, a supplementary cause of increased lead accumulation in these children. Indeed, dust and dirt samples collected on the school playgrounds at less than 1 km from the factory contained (mean ± SD) 3541 ± 1310 and 5466 ± 831 μg Pb/g, whereas at 2.5 km and in the rural area it only amounted to 397 ± 33 and 152 ± 41 μg Pb/g, respectively. The alternative explanation is that a continuous resuspension of dust and dirt particles from the highly contaminated soil around the lead smelter may maintain a very high airborne lead concentration at the breathing height of the children. In addition to a lasting reduction of lead emission from the plant, the remedial actions should also take into consideration these two possibilities.     

Air and blood lead levels in a battery factory.

Blood lead (Pb B) and air lead (Pb A) exposure levels were studied in workers (62) in a battery plant. Thirty-five battery workers had Pb B higher than 60 μg/100ml (OSHA Proposed Biologic Limit Value, (BLV), 1975). Fifty-eight workers had Pb Bs exceeding 40 μg/100 ml (OSHA Proposed BLV, 1978). Average Pb A for 33 battery workers was greater than 100 μg/m³, the newly recommended TWA. Average Pb A of approximately 50 μg/m³, (6 workers), 85 μg/m³ (17 workers), and 190 μg/m³ (10 workers) were associated with virtually identical mean Pb B (55.0, 59.5, and 58.4 μg/100ml). For 10 of 29 battery workers, Pb A less than 100 μg/m³ was associated with Individual Pb B greater than 60 μg/100 ml. At exposure levels of 329 μg/m³ (15 workers), 885 μg/m³ (3 workers), and 1187 μg/m³ (4 workers), associated mean Pb B was 75.2, 76.3, and 90.7 μg/100 ml, respectively. Complaints of fatigue, headache, abdominal pain, and loss of appetite were more frequent among 35 workers with Pb B > 60 μg/100 ml compared to 26 workers with Pb B < 60 μg/100 ml (relative risks 1.5, 1.4, 1.9, and 1.9, respectively). The relationship between group Pb A and individual Pb B was expressed by the equation: log Pb B (μg/100 cc) = 1.430 + 0.165 × log Pb A (μg/m³), r = 0.69. Battery factory data do not support the assumption that if Pb A were kept at or below 100 μg/m³, the blood lead levels would be less than 60 μg/100 ml.