Metal Concentrations and Responses of Chironomid Larvae Exposed to Thailand Pulp and Paper Mill Effluent

Pulp and paper mills (PPM) may discharge insufficiently treated waste into rivers and give rise to serious effects with aquatic life. This study investigated the biological response of the chironomid (Chironomus javanus, Kieffer) when exposed to PPM effluent. Effluent concentrations of BOD, COD, TKN, TS, Cr, Cu, Pb and Zn were high. Cd and Cr concentrations in chironomid were the most accumulated. Whole effluent toxicity on the chironomid test organism was significant as expressed by the percent survival and decreased with increasing concentration. Highest dry weight, head capsule and length of the chironomid test organism corresponded to 100% effluent at a specific time. Effect of dilution was assessed by using glutathione S-transferase activity on chironomid and corresponded to 6.25% effluent during 48–96 h which was significantly increased in the chironomid. The results showed that the chironomid was sensitive to PPM effluent and toxicity tests can be used for assessing the effect of effluent on aquatic species.     

Effects on Growth and Changes in Organ Distribution of Bullfrog Larvae Exposed to Lead Throughout Metamorphosis

Bulletin of Environmental Contamination and Toxicology - Amphibians are common components of freshwater ecosystems and can be exposed to lead (Pb) in contaminated habitats such as highway drainages...     

锌对出生前后铅暴露大鼠脑发育的保护作用

研究发现 ,铅不仅可透过胎盘屏障形成“宫内铅暴露”,而且还能透过血脑屏障造成中枢神经系统(CNS)结构、功能、代谢的改变。处于生长发育期的CNS对铅的毒性极为敏感 ,在血铅水平为 1 0 0μg/L甚至更低时即可导致患儿认知能力减退 ,智能低下等改变。因此应积极防范。本研究旨在观察锌对出生前后铅暴露幼鼠脑发育的保护作用 ,为锌干预亚临床型铅中毒对 CNS的毒性损害的可行性提供理论依据。1　材　料　与　方　法1 .1　动物模型建立与分组　　采用第三军医大学实验动物中心提供的 3月龄Wistar健康孕大鼠 2 0只 ,体重 (2 0 0± 1 5 ) g,随…     

铅锌矿区铅和镉污染对职业人群健康的影响

目的了解铅锌矿区铅镉污染对职业人群健康的影响。方法于2006年3月-2007年3月,选择长期工作和生活在某铅锌矿区的380名职工作为暴露组,以距该矿区40km以外东河上游某镇316名居民作为对照组,进行人群一般状况、内外科常见病检查（包括：自觉症状问诊、阳性体征筛查等）、职业病中毒体征（齿龈铅线、口内金属味、肢端感觉异常等）的检查。结果随着工龄的增加,职业人群发中铅、镉含量也随之增加（P〈0．05,P〈0．01）;暴露组人群头昏、胸闷、口内金属味、腹痛、肢端感觉异常及高血压发生率均高于对照组（P〈0．05,P〈0．01）;暴露组发中铅、镉、锌含量均高于对照组（P〈0．01）。结论铅锌矿区环境污染对职业人群健康有不良影响。     

Respiratory Abnormalities in Workers Exposed to Grain Dust

Survey of 68 grain elevator agents in Southern Manitoba disclosed that 75% had respiratory symptoms. Chronic cough and sputum, and dyspnea associated with exposure to grain dust were common. These symptoms were reported in more than half of the smokers and ex-smokers and in more than one quarter of the nonsmokers. Twenty-seven percent of the subjects also developed systemic symptoms of “grain fever” after exposure to grain dust. Lung function tests demonstrated abnormal spirometric results in 37%, while estimation of the “closing volume” demonstrated abnormality in 42.5% of the subjects, even after the values have been standardized for smoking habit. The high prevalence of respiratory symptoms and abnormal lung function among these subjects indicated that exposure to grain dust was an important etiologic factor in their development. Hypersensitivity to grain dust was found in eight subjects by prick skin testing and in six subjects by precipitin test. There was no significant correlation between the presence of positive skin or precipitin test and clinical disease.     

Biochemical Abnormalities in Workers Exposed to Molybdenum Dust

Exposure to molybdenum in dust was measured in a molybdenite roasting plant. This exposure was accompanied by large elevations of serum ceruloplasmin and smaller increases in mean serum uric acid levels in the workers. Absorption of molybdenum from the dust was demonstrated by increases in plasma and urinary molybdenum levels. It remains necessary to demonstrate whether such exposure results in long-term health effects.     

职业性铅接触工人血铅及肝功能指标的变化

[目的]研究职业性铅接触对工人的肝脏毒性,探讨血铅浓度变化和肝脏损害效应指标之间的关系,寻找铅对肝毒性的早期敏感指标。[方法]以蓄电池制造企业108名铅作业工人作为接触组,以同一企业非铅接触的76名工人和行政人员作为对照组。车间空气中铅烟、铅尘的短时接触浓度采用火焰原子吸收光谱法检测。选择丙氨酸氨基转移酶（ALT）和总胆红素（TBIL）作为肝毒性的效应指标,分析不同血铅水平和肝损害效应指标的变化。[结果]①车间空气中铅烟和铅尘的短时接触浓度分别为0.89mg/m3和0.25mg/m3,超标率分别为50.00%和60.00%。②随着环境铅接触水平的增加,ALT和TBIL的异常率增加无统计学意义（P〉0.05）。两者平均浓度变化也无统计学意义（P〉0.05）。③超职业限值组存在血铅超标现象,异常率为31.03%。超职业限值组和职业限值组血铅平均浓度明显高于对照组（P〈0.01）。④随着铅作业工龄的增加,血铅、ALT和TBIL的异常率无统计学意义（P〉0.05）。⑤血铅水平的变化和ALT、TBIL异常率的变化不存在相关关系。[结论]职业性铅接触引起血铅明显升高,肝功能效应指标ALT和TBIL不能敏感的反映铅对肝脏的毒性。     

人工家蚕蛹巴西虫草的致突变和致畸变研究

对人工家蚕蛹巴西冬虫夏草的致突畸变作用进行实验研究。结果显示：Ａｍｅｓ试验中的ＴＡ（９７）、ＴＡ（９８）、ＴＡ（１００）和ＴＡ（１０２）４个菌株分别在加和不加Ｓ９条件下平皿掺入法试验结果均阴性；小鼠骨髓ＰＣＥ微核试验和小鼠精子畸形试验也均阴性；致畸试验发现引起大鼠仔鼠顶骨和枕骨发育不全和缺失，大脑发育不全，腭裂和唇裂，高、中、低３组的畸形发生有剂量反应关系，其致畸原因尚待查明。     

钙锌对低水平铅暴露大鼠学习记忆的影响

铅污染对儿童最为常见和突出的影响是脑发育期低水平接触铅所致的中枢神经系统不可逆的功能障碍 ,主要表现为注意力和记忆力的改变 ,且可持续影响到成年阶段[1] 。体内铅蓄积与体内低钙、低锌水平之间存在着一种恶性循环 ,体内钙、锌的营养状况又会影响儿童学习记忆能力 [2 ,3 ]。本实验旨在为寻找防治铅对儿童智能损伤的有效手段提供实验和理论依据。1　材　料　与　方　法1 .1　动物分组与饲养　　二级 SD成年大鼠 (中山医科大学实验动物中心提供 )适应 7d后进入实验。每晚雌雄 2∶ 1同笼交配 ,次晨阴道涂片检查雌鼠 ,查到精子的当天为孕…     

硫酸锌和牛磺酸锌对铅染毒大鼠体重及学习记忆的影响

目的　探讨硫酸锌 (ZnSO4)和牛磺酸锌 (TZC)拮抗铅损害神经系统的作用。方法　采用测量体重增量和Y型迷宫实验 ,观察饮用 0 2 g/L 醋酸铅水溶液和含不同剂量ZnSO4(5 ,15 g/kg)、TZC(5 9,17 7g/kg) 饲料喂养的大鼠与饮用单蒸水和普通饲料喂养的大鼠之间体重增量和学习记忆能力的差别。结果　与对照组相比 ,铅染毒大鼠体重增量明显减少 (P <0 0 5 ) ,完成Y -迷宫实验次数明显增多(P <0 0 5 ) ;补充不同剂量ZnSO4和TZC对铅染毒大鼠体重增量和学习记忆均有明显改善作用 ,其中以低剂量TZC和高剂量ZnSO4效果更好。结论　锌能明显促进铅染毒大鼠体重增加及学习记忆能力增强。锌对铅损害神经系统有明显的拮抗作用。     

Ulcer and Gastritis in the Professions Exposed to Lead

The relationship of gastroduodenal ulcus, gas-tritis, and gastric chemism in 35 Workers suffering from saturnism and presaturnism was examined. The control group consisted of 94 patients with similar socoeconomic conditions and age. Gastritis was confirmed in 85.6% of saturnism and in 85.5% of presaturnism cases. Hypoacidity was confirmed in all the cases of saturnism and in 56% of cases with presaturnism. Considering both groups, hypoacidity was confirmed in 76.5% of the cases and in 54.4% of control group patients. Ulcus was not noted in cases of saturnism while the existence of presaturnism was noted in 12.5% of confirmed peptic ulcuses. Ulcus absence in saturnism, as well as its greater percentage in other population, indicates that there is no correlation between ulcus and mercury. The greater percentage of gastritis and hypoacidity is very significant     

Slowed Learning in Lambs Prenatally Exposed to Lead

Two groups of ewes were given lead sufficient to maintain mean blood lead levels of 34μg/100 ml (fed 4.5 mg/kg lead/day) and 18μg/100 ml (fed 2.3 mg/kg lead/day), respectively, throughout gestation.

Lambs from the two lead-exposed groups and from control ewes had blood lead levels of 24μg, 17μg, and 6μg/100 ml, respectively, at 2 to 4 weeks of age. Between 10 and 15 months of age, the lambs prenatally exposed to maternal blood lead levels of 34μg/100 ml required significantly more days to learn visual discrimination problems, while lambs exposed to maternal blood lead levels of 17μg/100 ml did not differ from the controls.     

竹叶抗氧化物的致畸和致突变性研究

目的研究竹叶抗氧化物的致畸性和致突变性.方法设1.43、2.87、4.30g/kg体重3剂量组,进行传统致畸研究;设8、40、200、1000和5000μg/皿5个剂量组,进行Ames试验:设2.5、5.0和10.0g/kg体重3个剂量组,观察其对小鼠骨髓细胞微核和小鼠精子畸形的影响. 结果 3剂量组各项指标均未见有明显的母体毒性和胚胎毒性、致畸性.各剂量组在体内体外致突变性研究中未见有致突变作用.结论在本实验条件下,竹叶抗氧化物无致畸性和致突变性.     

职业性铅接触工人神经肌电图分析

通过对１４０名铅作业工人神经系统检查和神经肌电图检查，发现虽临床上周围神经病表现不明显，但神经肌电图检查已发现神经传导速度减慢，末端潜伏期延长，且末端潜伏期的异常率显著高于传导速度异常率；肌电图改变符合神经源性损害。提示当前生产条件下铅作业工人存在着亚临床周围神经病的证据，其损害特点符合远端型轴索病。     

Neural Autoantibodies and Neurophysiologic Abnormalities in Patients Exposed to Molds in Water-Damaged Buildings

Adverse health effects of fungal bioaerosols on occupants of water-damaged homes and other buildings have been reported. Recently, it has been suggested that mold exposure causes neurological injury. The authors investigated neurological antibodies and neu-rophysiological abnormalities in patients exposed to molds at home who developed symptoms of peripheral neuropathy (i.e., numbness, tingling, tremors, and muscle weakness in the extremities). Serum samples were collected and analyzed with the enzyme-linked im-munosorbent assay (ELISA) technique for antibodies to myelin basic protein, myelin-associ-ated glycoprotein, ganglioside GM ₁, sulfatide, myelin oligodendrocyte glycoprotein, α-B-crystallin, chondroitin sulfate, tubulin, and neurofilament. Antibodies to molds and mycotoxins were also determined with ELISA, as reported previously. Neurophysiologic evaluations for latency, amplitude, and velocity were performed on 4 motor nerves (median, ulnar, peroneal, and tibial), and for latency and amplitude on 3 sensory nerves (median, ulnar, and sural). Patients with documented, measured exposure to molds had elevated titers of antibodies (immunoglobulin [I_g]A, I_gM, and I_gG) to neural-specific antigens. Nerve conduction studies revealed 4 patient groupings: (1) mixed sensory-motor polyneuropathy (n = 55, abnormal), (2) motor neuropathy (n = 17, abnormal), (3) sensory neuropathy (n = 27, abnormal), and (4) those with symptoms but no neurophysiological abnormalities (n = 20, normal controls). All groups showed significantly increased autoantibody titers for all iso-types (I_gA, I_gM, and I_gG) of antibodies to neural antigens when compared with 500 healthy controls. Groups 1 through 3 also exhibited abnormal neurophysiologic findings. The authors concluded that exposure to molds in water-damaged buildings increased the risk for development of neural autoantibodies, peripheral neuropathy, and neurophysiologic abnormalities in exposed individuals.     

Reproductive Ability of Workmen Occupationally Exposed to Lead

The reproductive ability of 150 men occupationally exposed to lead were studied by clinical and toxicological analysis. Subjects were divided into four groups: lead-poisoned workmen (23) and those showing a moderate (42), slight (35), or physiologic absorption (50).

Findings show that (1) Lead poisoning as well as moderate increased absorption of lead decrease the fertile ability of men. An increased frequency of asthenospermia, hypospermia, and teratospermia have objectified the decrease. (2) Slight increased or physiologic absorption of lead do not significantly influence the fertile ability of workmen. (3) Hypofertility induced by lead is due, perhaps, to its direct toxic effect on the gonads, as no interference with the hypothalamopituitary axis was evidenced.     

铅对作业工人某些内分泌腺功能影响的研究

本文研究发现铅吸收、铅中毒工人血中游离三碘甲状腺原氨酸（ＦＴ＿３）、游离四碘甲状腺原氨酸（ＦＴ－４）、皮质醇含量明显低于对照组工人（Ｆ＜０．０１），且与尿铅、尿δ－ＡＬＡ含量呈明显负相关；铅中毒工人血中ＴＳＨ明显高于对照组工人（Ｐ＜０．０１），且与尿铅、尿δ－ＡＬＡ含量呈明显正相关。结果提示，接铅工人体内铅负荷达铅吸收水平，但尚未产生中毒症状时就已影响了甲状腺、肾上腺皮质的分泌功能，说明某些内分泌腺对铅的损伤作用较敏感，铅损伤某些内分泌腺的功能可能是铅中毒的重要机理之一。     

铅作业工人血铅和氧化应激酶变化的研究

目的研究职业性铅接触者的氧化损伤,探讨血铅和氧化应激酶之间的变化关系,以探讨铅中毒的作用机制。方法采用火焰原子吸收分光光度法测定空气中的铅含量,用石墨炉原子吸收分光光度法测定血铅浓度,选择超氧化物歧化酶（SOD）和丙二醛脱氢酶（MDA）作为氧化应激损伤的效应指标,分析血铅与氧化效应指标的变化。结果共采集了车间内5个工作点的空气样品。接触组血铅浓度（244．274±124．59）μg／L,显著高于对照组（P〈0．01）;接触组SOD活性（61．27±6．97）KU／L,与对照组比较无统计学差异（P〉0．05）;接触组MDA含量（9．42±3．89）mmol／L,显著高于对照组（P〈0．01）;血清MDA含量与血铅之间存在正相关关系（r=0．3,P〈0．01）;吸烟、饮酒对SOD活性和MDA含量影响无统计学差异。结论职业性铅接触引起人体血铅升高,作业场所空气中铅浓度与血铅含量变化不一致,血铅是近期铅接触者的敏感内接触指标,且血铅浓度越高,SOD活性代偿性升高;MDA含量越高,氧化损伤越明显。