Distribution of asbestos in the bedrock of the northern New Jersey area

Asbestos has been identified at fifty-five locations in the bedrock of the northern New Jersey area. Most occurrences are confined to (1) The Precambrian rocks of the New Jersey Highlands, particularly the marbles; (2) the Paleozoic serpentinites of Staten Island, New York, and Hoboken, New Jersey; and (3) the Mesozoic basaltic rocks of the Newark Basin. Chrysotile and tremolite asbestos are present in local concentrations in the marbles. In the most extensive exposure of the marble, the Franklin band, traces of tremolite-actinolite asbestos are commonly present. Crocidolite asbestos occurs in localized areas associated with fracture systems in Precambrian pegmatites and associated rocks. The Paleozoic serpentinites contain chrysotile asbestos as a major component in deformed zones. Megascopic chrysotile and anthophyllite asbestos veins occur locally in the serpentinites. Actinolite asbestos occurs in the Mesozoic basaltic rocks of the Newark Basin. Potential environmental problems associated with asbestosbearing bedrock include production and use of rock products containing asbestos, introduction of asbestos into environments surrounding excavations, and asbestos contamination of soils and water supplies.     

我国四大矿区温石棉粉尘诱导A549细胞凋亡和周期阻滞的对比研究

通过FT-IR和XRD对四川新康、陕西陕南、甘肃阿克塞和青海茫崖四大矿区温石棉的物相成分、谱学特征进行测试分析,利用MTT法、流式细胞术检测了4种温石棉纤维粉尘染毒A549细胞后的细胞存活率、凋亡率和细胞周期分布,比较和探讨了四大矿区温石棉纤维粉尘抑制细胞增殖能力的大小及其对细胞凋亡和周期阻滞的影响。研究结果显示,四大矿区温石棉的主要物相是斜纤蛇纹石,新康温石棉成分比其他3种温石棉的复杂,阿克塞和茫崖温石棉的成分相似;四大矿区的温石棉化学基团基本相同,阿克塞和茫崖温石棉纤维的表面结构较陕南和新康温石棉的完善。4种温石棉均能不同程度地抑制A549细胞增殖,诱导细胞凋亡和周期阻滞:茫崖组凋亡率最大(22. 56±2. 56)%,陕南组凋亡率最小(19. 57±3. 07)%;细胞周期阻滞均以G2/M期阻滞为主,新康、陕南、阿克塞和茫崖组处于G2/M期细胞比例分别增加8. 90%、8. 58%、9. 13%和10. 44%。4种温石棉导致细胞凋亡和周期阻滞的能力:茫崖新康阿克塞陕南。     

纤蛇纹石石棉的纳米效应与生物活性

本文首次从纳米材料与纳米效应角度出发讨论了纤蛇纹石石棉的形态、表面结构、表面性质与生物活性的关系。结果表明,纤蛇纹石石棉属自然界产出的一种特殊的一维纳米丝状矿物,在形态、结构和表现性质等方面表现出纳米材料所具有一般特性,其中,形态上一寸及高表面化学活性构成了它的生物活性特征。纤蛇纹石石棉纤维对动物的危害,既具有一般纤维的危害性,又具有非晶质ＳｉＯ２的危害性。由于纤维的小尺寸效应和高表面活性而使生物     

我国西北地区不同类型纤蛇纹石石棉的电镜研究

作者对西北地区不同类型温石棉矿床的石棉进行了扫描电镜和高分辩率透射电镜研究,拍摄到清晰的晶格象和电子显微象,发现茫崖型和小八宝型的温石棉纤维的晶格条纹、晶格缺陷及纤维形貌有明显差异。这种差异与成棉地质条件和温度有关。     

基于多次非暴露式气管滴注的染毒法研究温石棉致大鼠肺损伤的作用

温石棉是一种安全性存在争议的石棉,合理可行并且能够真实反映其暴露致病过程的染毒方法对深入研究其致病机理有着重要意义。本文采用多次非暴露式气管滴注的染毒方法对雄性Wistar大鼠分别进行不同浓度温石棉悬液的染毒,在染毒1、3和6个月后记录体重和肺脏器系数,观察肺组织大体及苏木素-伊红(HE)染色的病理形态,对支气管肺泡灌洗液(BALF)中白细胞总数进行分类计数,并测定总蛋白(TP)、乳酸脱氢酶(LDH)、酸性磷酸酶(ACP)和碱性磷酸酶(AKP)的含量。结果表明,多次滴注的方式大鼠死亡率较低,并且每次滴注后能够苏醒的大鼠没有死亡发生;随着四川新康温石棉染毒时间的延长和染毒剂量增加,大鼠体重增长缓慢,肺脏器系数升高,肺大体出现水肿、肉芽肿、萎缩实质化,HE染色观察则表现为炎性细胞增多、肺泡结构遭到破坏以及出现纤维化;随着染毒时间的延长,支气管肺泡灌洗液(BALF)中的白细胞总数、中性粒细胞和淋巴细胞百分比呈上升趋势,巨噬细胞百分比呈下降趋势,TP、LDH、ACP和AKP均表现为上升的趋势,并呈现一定的剂量-效应关系。综上所述,多次非暴露式气管滴注方法可用于模拟温石棉慢性暴露的致病过程,四川新康温石棉可以通过破坏巨噬细胞、肺泡上皮细胞及肺泡上皮-毛细血管屏障造成大鼠的肺损伤。     

4种天然温石棉致大鼠肺损伤及对HO-1和HSP-70的影响

探讨了我国四大矿区天然温石棉致大鼠肺部损伤作用及肺组织中HO-1和HSP-70的表达差异。从我国四大天然矿区采集4种天然温石棉,用扫描电镜、红外光谱和X射线荧光光谱分析其粉尘形貌、表面活性基团和化学组分。将90只初断乳SPF级Wistar大鼠,随机分为5组(甘肃阿克塞、青海茫崖、四川新康、陕西陕南温石棉组和生理氯化钠溶液阴性对照组),用2. 0 mg/m L温石棉粉尘悬液0. 5 m L(1次/月)对大鼠非暴露式气管内滴注染毒。于1、6、12个月分批处死大鼠6只,测定支气管肺泡灌洗液(BALF)中的乳酸脱氢酶(LDH)、碱性磷酸酶(AKP)和总蛋白(TP)含量,采用qRT-PCR检测肺组织中血红素氧化合酶1(HO-1)和热休克蛋白70(HSP-70) mRNA表达水平,采用western blot检测肺组织中HO-1和HSP-70蛋白表达水平。结果显示,阿克塞、茫崖和新康温石棉组LDH及各温石棉组AKP和TP在各时间点均比阴性对照组高(P 0. 05),且随染毒时间延长呈上升趋势(P 0. 05)。染毒1月时,各染毒组HO-1、HSP-70 mRNA和HO-1、HSP-70蛋白表达量比阴性对照组高(P 0. 05);染毒6月时,各染毒组比阴性对照组高,阿克塞和陕南温石棉组低于茫崖和新康温石棉组(P 0. 05);染毒12月时,阿克塞和陕南温石棉组高于茫崖和新康温石棉组(P 0. 05),茫崖和新康温石棉组低于阴性对照组。     

Naturally occurring asbestos in eastern Australia: a review of geological occurrence,disturbance and mesothelioma risk

Potential asbestos-bearing rocks account for about 0.2% of the land area of eastern Australia. The main mode of occurrence is as narrow cross fibre and slip fibre veins of chrysotile asbestos in serpentinised ophiolite complexes along the boundaries of major tectonic domains. Smaller deposits of chrysotile and amphibole asbestos occur in metamorphosed mafic and ultramafic rocks associated with the Macquarie Volcanic Arc in New South Wales. Amphibole asbestos is also known from Proterozoic and Palaeozoic amphibolite and from Devonian basalt. Natural asbestos-bearing materials in eastern Australia have been disturbed by mining, road construction, agriculture and forestry, urban development and through natural weathering processes. Persons most at risk of potential exposure to asbestos from natural sources include: farmers who work or live in areas where asbestos-bearing materials may be routinely disturbed by agricultural activities; construction workers involved in large-scale earthwork projects in areas underlain by asbestos-bearing rocks; and quarry workers who unwittingly disturb asbestos-bearing materials. Government authorities and private enterprise need to take geological factors into account to reduce the likelihood of unplanned disturbance of natural asbestos-bearing materials. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

The schoolroom asbestos abatement program: a public policy debacle

It is estimated that nearly $100 billion has been spent on removal of asbestos-bearing materials from schoolrooms, public and commercial buildings, and homes. This removal continues to this day despite the publication of an advisory document in 1990 by the US Environmental Protection Agency that states most removal is unnecessary and is even counterproductive both in terms health protection and costs. Concern over low exposure to substances that are designated as carcinogens is based on the false concept that even the smallest exposure to such substances can increase cancer risk. The expression one molecule of a chemical or one asbestos fiber can possibly produce a tumor is repeated over and over until it is accepted as a truth. Over 1400 air samples taken in 219 North American school buildings show the average fiber level to be 0.00022 fibers per milliliter of air. Using the most pessimistic models and attendance in the school for 6 h a day, five days a week, for 14 years, the calculated risk is one excess cancer death per million lifetimes. In contrast, the risk of dying from a lightning strike is 35 deaths per million lifetimes. Ambient air asbestos concentrations measured in the chrysotile asbestos mining towns of Quebec are 220 to 2200 times greater than that measured in the average schoolroom, yet the women living their entire lives in these towns show no increased cancer risk. The asbestos abatement program in the United States is a public policy debacle.     

四川石棉矿蛇纹石矿物学研究

四川石棉矿产出四种蛇纹石矿物:纤蛇纹石,Povlen型纤蛇纹石、利蛇纹石和叶蛇纹石。它们的形态、结构、化学成分和红外光谱各具特征,本文对此进行了描述和讨论。纤蛇纹石以纵纤维脉和横纤维脉形式产出,以斜纤蛇纹石为主,含少量正纤和副纤蛇纹石。纵纤维蛇纹石可能由地壳浅层中的大气热水形成。Povlen型纤蛇纹石是蛇纹石族矿物的一个新变种,其形态、结构和化学成分都不同于其他蛇纹石矿物。     

Quality of chrysotile asbestos and high-temperature conductance of the host ultramafics: possible linkage

The paper reports physical, physicochemical, and mineralogical-petrographic studies of serpentinite samples from the Bazhenovo deposit of chrysotile asbestos. The samples differ in mineralogy, physical and physicochemical parameters, and in quality (fiber tenacity) of the hosted chrysotile asbestos. The experiments allowed estimating the temperature dependence of electrical resistance of serpentinites in a range of 20 to 800 °C, the parameters of their high-temperature resistance (the activation energy E₀ and the resistance coefficient lg R₀), and the relationship between fiber tenacity of asbestos and high-temperature conductance of the host serpentinites. The serpentinite samples that host brittle and tenacious chrysotile asbestos plot different fields in the coordinates E₀–lg R₀ without any overlap. Thus, the quality of chrysotile asbestos can be inferred from the parameters of high-temperature conductance of the host serpentinites.     

温石棉通过活性氧激活线粒体通路诱导A549细胞凋亡的机制研究

探讨活性氧(reactive oxygen species,ROS)在温石棉激活线粒体通路诱导A549凋亡中的作用。采用不同浓度温石棉粉尘染毒人肺上皮细胞(A549)后,MTT法检测细胞存活率,流式细胞术检测ROS抑制剂N-乙酰半胱氨酸(N-acetyl-L-cysteine,NAC)预处理前后的细胞凋亡率、胞内ROS水平及线粒体膜电位,Western Blot法检测各组细胞半胱天冬氨酸蛋白酶3(caspase-3)、p53蛋白表达水平。实验结果显示,温石棉可降低A549细胞存活率,呈现时间-剂量效应关系;NAC可显著减少胞内ROS水平、阻止线粒体膜电位下降,并下调caspase-3、p53蛋白的表达水平,抑制部分细胞凋亡的发生。表明ROS可通过诱导p53蛋白过表达,激活线粒体凋亡通路,诱导A549细胞发生凋亡。     

辽宁朝阳南部蛇纹石石棉矿床成因探讨

本区蛇纹石石棉矿床,前人多认为属岩浆期后中一低温热液交代矿床。笔者通过实地考察,室内分析、鉴定,认为本区蛇纹石石棉矿床属改造型层控矿床。一、成矿地质条件及矿(化)带基本特征本区位于朝阳市西南部,北起灵山庙—谢家杖子,南至上柳树杖子,东起吴大成沟一大柏山,西至波针沟,面积约45km~2。其大地构造位置处于华北地台燕山台褶带北段,朝阳—建昌复背斜中段西翼。区域构造由苏家店—柳树杖子背斜及长茂河子—马家店向斜组成,总体方向北东;主要断层方向与褶皱构造线方向一致。     

The zeta-potentials of natural and synthetic chrysotiles

Different specimens of the asbestos mineral chrysotile show widely different zeta-potentials. Strongly positive values are found with samples containing an excess of magnesia in the form of brucite, Mg(OH)₂. Synthetic chrysotile and natural samples containing little or no brucite give moderately positive ζ-values over the pH range 3–11. Feebly positive or weakly negative natural chrysotiles are materials which have suffered weathering; and deliberate acid-leaching of any chrysotile ultimately leaves a strongly negative pseudomorph of silica gel.Since the pH and the ambient concentration of Mg²⁺ ions near the surface are the main factors controlling ζ, and since chrysotile is readily susceptible to leaching in practically all aqueous media and does not come to a true ionic equilibrium in any practical time, the zeta-potential of an ideal chrysotile surface is a hypothetical concept.The results also explain the temporary colloidal stability of very dilute suspensions of chrysotile in weakly acidic media and the mutual coagulation of chrysotile and amosite slurries.     

Restrictive definition of asbestos and the assessment of potential health hazards: insights from Northern Chile

When asbestos fibres become airborne, they can be inhaled into the lungs, where they may cause significant health problems. The latter includes progressive pulmonary fibrosis (asbestosis), pleural disease (effusion and pleural plaques) and malignancies such as bronchogenic carcinoma and malignant mesothelioma. The term asbestos applies to a group of hydrated fibrous mineral silicates including those belonging to the serpentine group of phyllosilicates (chrysotile) and amphiboles. However, only the ‘asbestiform varieties’ of amphiboles such as grunerite (amosite), riebeckite (crocidolite), anthophyllite, tremolite and actinolite are regarded as asbestos (s.s.). This implies that ‘non-asbestiform varieties’ of such minerals, that nevertheless generate acicular cleavage fragments, cannot be regarded as asbestos s.s. We argue that a discussion on the term asbestos goes beyond mere semantics, because for environmental regulatory bodies, the definition of a term can make the difference between classifying a mineral as harmful or non-harmful. A case of mesothelioma in the small mining town of La Higuera, northern Chile, may shed some light into this matter, because this form of cancer is almost always caused by exposure to asbestos. The town hosts about 20,000 t of fine-grained tailings left behind after flotation of Cu sulphides during 1950–1979. The ore was extracted from actinolite-rich, copper-iron vein deposits. We show that, if a ‘non-asbestiform variety’ of amphibole (e.g. La Higuera actinolite) is finely ground, it will cleave to asbestos-like acicular crystals and as such has the potential to induce similar health hazards to those posed by asbestos (s.s.).     

Petrographic and mineral chemistry investigation of the high-grade chrysotile asbestos-bearing Zvishavane Ultramafic Complex,south central Zimbabwe

The Zvishavane Ultramafic Complex (ZUC) in the south central part of the Zimbabwe craton is comprised of coarse-grained serpentinites, metadunites and metagabbros and hosts Africa's largest reserves, and largest mine, of high-grade chrysotile asbestos. Magnesiohornblende, actinolite, plagioclase (An_0.6–41.9), augite, diopside and clinozoisite constitute the mineralogy of the ZUC. Forsteritic olivine (>Fo₉₀) was altered to form chrysotile and antigorite minerals, although some primary olivines are preserved. Contents of Al₂O₃ range from <1 to >2.5 wt% at TiO₂ values of <0.7 wt% consistent with an island arc setting for the ZUC that originated from tholeiitic magmas. The Zvishavane Ultramafic Complex was metamorphosed at relatively high temperatures (542-779 °C) and low pressures (1.2-2kbars), consistent with contact metamorphism. Intrusion of several granitic batholiths relatively close to the ZUC likely triggered hydrothermal fluid migration which metamorphosed the ZUC. The associated asbestos deposits likely formed during hydrothermal circulation events. Zoned amphiboles, the occurrence of magnesiohornblende and actinolite, as well as cross-cutting serpentine veins are consistent with at least two stages of alteration and/or metamorphism of the ZUC. The lack of a thrust contact between the ZUC and its country rocks is consistent with the ZUC having intruded into the host Zvishavane Gneiss Complex and possibly acted as a feeder to the nearby Mberengwa greenstone belt (MGB). However, the occurrence of near end-member forsteritic olivine, the presence of zoned amphiboles, and faulting within the ZUC are all suggestive of an ophiolitic origin although forsteritic olivines also occur in intrusive layered complexes. Metamorphism of the ZUC, ascribed to intrusion of multiple batholiths and possibly the MGB, likely led to the formation of ZUC chrysotile asbestos deposits.     

Aquifer geochemistry at potential aquifer storage and recovery sites in coastal plain aquifers in the New York city area,USA

The effects of injecting oxic water from the New York city (NYC) drinking-water supply and distribution system into a nearby anoxic coastal plain aquifer for later recovery during periods of water shortage (aquifer storage and recovery, or ASR) were simulated by a 3-dimensional, reactive-solute transport model. The Cretaceous aquifer system in the NYC area of New York and New Jersey, USA contains pyrite, goethite, locally occurring siderite, lignite, and locally varying amounts of dissolved Fe and salinity. Sediment from cores drilled on Staten Island and western Long Island had high extractable concentrations of Fe, Mn, and acid volatile sulfides (AVS) plus chromium-reducible sulfides (CRS) and low concentrations of As, Pb, Cd, Cr, Cu and U. Similarly, water samples from the Lloyd aquifer (Cretaceous) in western Long Island generally contained high concentrations of Fe and Mn and low concentrations of other trace elements such as As, Pb, Cd, Cr, Cu and U, all of which were below US Environmental Protection Agency (USEPA) and NY maximum contaminant levels (MCLs). In such aquifer settings, ASR operations can be complicated by the oxidative dissolution of pyrite, low pH, and high concentrations of dissolved Fe in extracted water.     

Identification of chrysotile in local soil at Beypinari village (Sivas-Turkey) regarding mine and health issue

Asbestos is dangerous for health and is forbidden to use in Turkey, but villagers who live in rural eastern part still use it especially for their home for insulation purposes and even as a substitute for baby powder. Therefore, geological and chemical properties of this type of soil, which is near the settlement, should be characterized and identified from the point of view of health. Beypinari asbestos deposits are located at Beypinari village, about 90 km southeast of Sivas, Turkey within Central Anatolian Ophiolites. Therefore, in the present study, the existence of chrysotile in Beypinari asbestos deposit were characterized and identified by mineralogical analysis and by major, trace, REE analysis. The results show that the samples contain different amount of calcite mineral, the main mineral being chrysotile.     

Minerogenic Model of Chrysotile Deposits in Ultramafic Rocks

Most chrysotile deposits occur in ultramafic rocks of the ophiolite suite. The chrysotile deposits dis-cussed in the present paper were formed through metasomatism and infilling-crystallization in a continentalserpentinization environment after plate convergence, where ultramafic rocks were replaced byhydrothermal solutions consisting mainly of deep-circulating heated water derived from atmospheric precip-itation. The critical state for the formation of asbestos in ultramafic rock bodies might be reached bysuperposition of multiple stages of serpentinization. Favourable fracture systems and relatively stable geo-logical environment are important conditions for forming chrysotile deposits. Three subtypes of chrysotiledeposits could be formed in different tectonic settings and under different minerogenic geochemical condi-tions.     

Asbestos and other fibrous minerals contained in the serpentinites of the Gimigliano-Mount Reventino Unit (Calabria,S-Italy)

Serpentinites are metamorphic rocks with good technological properties and valuable ornamental characteristics, which have been exploited since ancient times. Actually, their use is limited and monitored in several countries worldwide because they can contain fibrous asbestos minerals that may be carcinogenic. Furthermore, certain types of fibrous minerals can be confused with asbestos, and must therefore be carefully investigated. We have investigated the possible presence of the asbestos and non-asbestos fibrous phases contained in serpentinitic rocks in a meta-ophiolitic sequence from the Gimigliano-Mount Reventino Unit (Southern Italy), which had not been previously assessed. The detection and quantification of asbestos and the correct distinction of the fibrous non-asbestos minerals are very important not only from a scientific point of view, but also from a legislative one. This is especially the case for the administrative agencies that have to take decisions with regards to the implementation of public and occupational health protection measures (e.g., in road yards and quarry excavations). As a consequence of this, serpentinitic rock samples have been characterized in detail through X-ray powder diffraction, scanning and transmission electron microscopy combined with energy-dispersive spectrometry, analytical electron microscopy (SEM–EDS and TEM–AEM), differential scanning calorimetry, thermogravimetry and micro-Raman spectroscopy. Two kinds of asbestos and four kinds of non-asbestos fibrous silicates have been detected in the examined samples. In order of decreasing abundance these are polygonal serpentine, chrysotile, fibrous antigorite, tremolite, gedrite and magnesiohornblende. The size, morphology, crystallinity and chemical composition of the fibres were also discussed, in the light of the possible role these properties could play in the carcinogenic effect on human health.     

水热条件对纤蛇纹石纳米管合成的影响研究

采用水热法在不同反应条件下合成了一系列纤蛇纹石纳米管.利用红外吸收光谱、扫描电镜和透射电镜系统地研究了水热反应中,反应温度、Si/Mg比、反应时间等不同反应参数对合成纤蛇纹石纳米管的晶体生长及其结构的影响.结果表明,温度的升高、Si/Mg比趋近0.68及反应时间的延长均有利于纤蛇纹石的生长,并获得最佳条件下合成的纤蛇纹石条件.