Chronic arsenic poisoning from burning high-arsenic-containing coal in Guizhou, China

Arsenic is an environmental hazard and the reduction of drinking water arsenic levels is under consideration. People are exposed to arsenic not only through drinking water but also through arsenic-contaminated air and food. Here we report the health effects of arsenic exposure from burning high arsenic-containing coal in Guizhou, China. Coal in this region has undergone mineralization and thus produces high concentrations of arsenic. Coal is burned inside the home in open pits for daily cooking and crop drying, producing a high concentration of arsenic in indoor air. Arsenic in the air coats and permeates food being dried producing high concentrations in food; however, arsenic concentrations in the drinking water are in the normal range. The estimated sources of total arsenic exposure in this area are from arsenic-contaminated food (50-80%), air (10-20%), water (1-5%), and direct contact in coal-mining workers (1%). At least 3,000 patients with arsenic poisoning were found in the Southwest Prefecture of Guizhou, and approximately 200,000 people are at risk for such overexposures. Skin lesions are common, including keratosis of the hands and feet, pigmentation on the trunk, skin ulceration, and skin cancers. Toxicities to internal organs, including lung dysfunction, neuropathy, and nephrotoxicity, are clinically evident. The prevalence of hepatomegaly was 20%, and cirrhosis, ascites, and liver cancer are the most serious outcomes of arsenic poisoning. The Chinese government and international organizations are attempting to improve the house conditions and the coal source, and thereby protect human health in this area.     

砷中毒地区外环境砷暴露水平的研究现状

地方性砷中毒是一种严重危害病区居民健康的地方病.根据砷源不同,分为饮水型职业性砷中毒、燃煤型职业性砷中毒和职业性砷中毒.饮水型地方性砷中毒主要是由于长期暴露于饮用水中的砷而引起的慢性砷中毒.饮水中的砷还可以通过农田灌溉等引起粮食、土壤等砷浓度的升高,间接危害居民健康.在以往的研究中发现,饮水型砷中毒地区饮用水砷超标,不...     

Urinary Arsenic Speciation and its Correlation with 8-OHdG in Chinese Residents Exposed to Arsenic Through Coal Burning

In contrast to arsenicosis caused by consumption of water contaminated by naturally occurring inorganic arsenic, human exposure to this metalloid through coal burning has been rarely reported. In this study, arsenic speciation and 8-hydroxy-2′-deoxyguanosine (8-OHdG) levels in urine were determined in the Chinese residents exposed to arsenic through coal burning in Guizhou, China, an epidemic area of chronic arsenic poisoning caused by coal burning. The urinary concentrations of inorganic arsenic (iAs), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA) and total arsenic (tAs) of high-arsenic exposed subjects were significantly higher than those of low-arsenic exposed residents. A biomarker of oxidative DNA damage, urinary 8-OHdG level was significantly higher in high-arsenic exposed subjects than that of low exposed. Significant positive correlations were found between 8-OHdG levels and concentrations of iAs, MMA, DMA and tAs, respectively. In addition, a significant negative correlation was observed between 8-OHdG levels and the secondary methylation ratio (DMA/(MMA + DMA)). The results suggest that chronic arsenic exposure through burning coal rich in arsenic is associated with oxidative DNA damages, and that secondary methylation capacity is potentially related to the susceptibility of individuals to oxidative DNA damage induced by arsenic exposure through coal burning in domestic living.     

中国地方性砷中毒分布调查(总报告)

为查清我国地方性砷中毒的基本分布 ,指导和推进我国的地方性砷中毒的防治工作 ,采用环境流行病学调查方法 ,包括回顾性环境流行病学调查 ,重点病区调查和面上抽样调查 ,搜集掌握病情资料。采用环境化学标准方法与质量控制分析环境砷水平 ,回顾性调查中利用己有的环境砷资料 ,重点调查与面上抽样现况调查中检测环境砷含量。最后对二者结果进行计算机统计分析。饮水型地方性砷中毒分布于 8省市区 ,40个县旗市 ,受影响人口 2 3 4 3 2 3 8人 ,其中饮水砷 >0 .0 5mg L高砷暴露人口 52 2 566人 ,查出砷中毒 782 1人。内蒙、山西仍为我国饮水型地方性砷中毒重病区 ,新疆乌苏市的生产建设兵团与乌苏中的大部分高砷地区集中改水 ,病情减轻。内蒙、山西的一些乡村集中改水降砷效果较好。新确认吉林、宁夏各 1县饮水型地方性砷中毒 ,其中以吉林省病区为典型。新发现山西 11县市、内蒙 1旗、吉林 1市、宁夏 1县、青海 1县和安徽 2县市的饮水型地方性砷中毒。新发现北京顺义区仍有饮水高砷暴露乡镇。未发现其它省、市、自治区有饮水高砷暴露地区。确认辽宁省曾报道的饮水高砷点现已消除 ;浙江桐乡市已有的饮水高砷地区现已降至饮水砷卫生标准以下 ;并发现北京市顺义区天竺乡天竺村连续 2 0余年的饮水高砷井自然转变?     

Urinary porphyrins in patients with endemic chronic arsenic poisoning caused by burning coal in China

Objective  To evaluate the effect of arsenic (As) on the porphyrin biosynthetic pathway, urine samples from patients with endemic chronic arsenic poisoning were examined. Subjects and Methods  The subjects were 16 patients, who had been exposed to As from burning coal for 8 to 25 years, and 16 controls living in the same region in Guizhou Province in southwest China. Concentrations of urinary As, porphyrins and ALA were determined by induced coupled plasma mass spectrometry (ICP-MS), high performance liquid chromatography (HPLC) with a reversed-phase column and fluorescence detector, and colorimetric spectrophotometry, respectively. Results  Concentrations of As in patients and controls, 184.40±200.04 and 86.82±64.20μ g/g creatinine (mean ±SD) respectively, were significantly different (p<0.05). The concentrations of various kinds of urinary porphyrins, including isomers I and III of coproporphyrin and pentacarboxylporphyrin, were determined. Positive correlations were observed between As and porphyrins (e.g. total porphyrins, hexacarboxylporphyrin and coproporphyrin III) or between As and ALA in male and female patients. However, porphyrin and ALA concentrations were not significantly different between the patients and the controls. Urinary porphyrin concentrations in females were higher than those in males. Conclusion  Exposure to As from burning coal may influence porphyrin biosynthesis.     

中国农村室内空气污染及其对健康的危害

[目的]综合分析中国农村居室内空气污染现状及其对农民健康的危害,为进一步研究污染控制提供线索.[方法]收集1994～2005年间发表的有关中国农村室内空气污染及其危害研究的中文文献,进行去伪存真、整理、汇总.文献中不包括燃煤所致的砷和氟污染及其慢性中毒的研究.[结果]冬季家庭燃煤取暖是现阶段中国北方农村室内空气污染的主要原因.中国农村室内空气的污染程度与区域、季节、燃料燃烧状态、燃料种类,以及大气质量、住房结构、室内通风状况等条件有关.中国农村室内空气污染与农民慢性阻塞性肺部疾病、肺癌、呼吸系统症状和肺功能改变的关系较为密切.[结论]中国农村室内空气污染主要来源于室内燃料的燃烧,特别是煤的燃烧,并已对农民健康产生了危害.改炉改灶、行为干预、改换燃料等行之有效的措施,势在必行.     

黔西南一小型锑冶炼厂环境污染调查分析

目的 了解小型锑冶炼厂对周围环境的影响。方法 对黔西南一小型锑 冶炼厂矿石、燃用煤以及周围土壤和植物样品进行了分析。结果 锑冶炼厂周围土壤中元素含量与全国土壤中元素平均含量比较,As、Hg、F、Sb、Se的含量明显偏高,As为1.73-4.96倍,Hg为4.75-237.5倍,F为2.26-3.42倍,Sb为35.6-36.2倍,Se为54.29-57.14倍;也高于贵州土 的平均含量,As为1.25-3.58倍,Hg为1.86-93.14倍,F为1.38-2.08倍,Se为33.04-34.78倍。玉米叶片中As、Hg、F、Sb、Se含量高于大陆植物中相应元素平均含量,As为67倍,Hg为26.7倍,F为1046.4倍,Sb为2220倍,Se为38.8倍。结论 锑冶炼厂排放的S、As、Hg、F、Sb和Se对环境造成了严惩的污染,高硫燃料煤的利用也加剧了环境的污染。     

Reduction in Kidney Cancer Mortality Following Installation of a Tap Water Supply System in an Arsenic-Endemic Area of Taiwan

Arsenic is the major risk factor for blackfoot disease, a peripheral vascular disease that has been endemic to the southwest coast of Taiwan for more than 50 yr because of the consumption of local artesian well water containing high levels of arsenic. Long-term arsenic exposure has been associated with kidney cancer mortality in a dose-response relationship. In the early 1960s, a tap water supply system was implemented in the blackfoot-endemic areas. After the mid-1970s, artesian well water was no longer used for drinking or cooking in the region. The authors examined whether kidney cancer mortality decreased after the elimination of arsenic exposure from artesian well water. Standardized mortality ratios for kidney cancer were calculated for the blackfoot-endemic area for the years 1971–2000. Study results showed that mortality from kidney cancer declined gradually during this time; therefore, the association of arsenic exposure with kidney cancer mortality was likely causal.     

Reduction in kidney cancer mortality following installation of a tap water supply system in an arsenic-endemic area of Taiwan

Arsenic is the major risk factor for blackfoot disease, a peripheral vascular disease that has been endemic to the southwest coast of Taiwan for more than 50 yr because of the consumption of local artesian well water containing high levels of arsenic. Long-term arsenic exposure has been associated with kidney cancer mortality in a dose-response relationship. In the early 1960s, a tap water supply system was implemented in the blackfoot-endemic areas. After the mid-1970s, artesian well water was no longer used for drinking or cooking in the region. The authors examined whether kidney cancer mortality decreased after the elimination of arsenic exposure from artesian well water. Standardized mortality ratios for kidney cancer were calculated for the blackfoot-endemic area for the years 1971-2000. Study results showed that mortality from kidney cancer declined gradually during this time; therefore, the association of arsenic exposure with kidney cancer mortality was likely causal.     

Health aspects of burning coal with a high arsenic content: I. Arsenic in hair,urine, and blood in children residing in a polluted area

Arsenic determination was carried out on hair, urine, and blood samples taken from groups of 10-year old boys, each numbering 20 to 25 individuals, residing in a region polluted by arsenic. The source of arsenic emissions ($\text{1}\text{2}$ to 1 ton per day) is a power plant burning local coal of high arsenic content. In all the materials examined, considerably elevated concentrations of arsenic were found. The relation of the observed levels of arsenic to the distance of the place of residence up to a distance of more than 30 km from the source of the emissions was studied. On the basis of the results obtained, the most advantageous material for estimation of nonoccupational exposure to this toxic agent seems to be hair, in spite of some problems with the decontamination procedure involved. The results corresponded to the theoretical ideas on spreading of emissions from elevated sources in the open air and tend to establish the applicability of arsenic determination in the hair as a direct exposure test of contamination of the environment by arsenic. Considerable variablility among individual arsenic values in the hair makes group examination a necessity. The same applies to the urine and blood sampling, which is complicated by several technical difficulties. Levels in urine reflect the quantities of arsenic inhaled or ingested after their absorption into the blood, and give a more realistic picture of possible daily intake.     

Unventilated indoor coal-fired stoves in Guizhou province, China: cellular and genetic damage in villagers exposed to arsenic in food and air

BACKGROUND: Inorganic arsenic (iAs) is a well-known human carcinogen recognized by the World Health Organization and the International Agency for Research on Cancer. Currently, most iAs studies in populations are concerned with drinking water and occupational arsenicosis. In Guizhou province, arsenicosis caused by the burning of coal in unventilated indoor stoves is an unusual type of exposure. Because the poisoning mechanism involved in arsenicosis is as yet unknown and no effective therapy exists, progress has been slow on the prevention and therapy of arsenicosis. OBJECTIVES: We examined the relationship between arsenic (As) exposure from the burning of coal in unventilated indoor stoves and genetic damage in humans, using cellular and molecular indices. We selected villagers from Jiaole township, Guizhou province, China, who had been exposed to milligram levels of As daily via food and air contaminated by the burning of As-containing coal in unventilated indoor stoves. RESULTS: The As-exposed subjects from Jiaole were divided into four groups according to skin lesion symptoms: nonpatients, mild, intermediate, and severe arsenicosis. Another 53 villagers from a town 12 km from Jiaole were recruited as the external control group. In the four groups of exposed subjects, As concentrations in urine and hair were 76-145 microg/L and 5.4-7.9 microg/g, respectively. These values were higher than those in the external control group, which had As concentrations of 46 microg/L for urine and 1.6 microg/g for hair. We measured sister chromatid exchange and chromosomal aberrations to determine human chromosome damage, and for DNA damage, we measured DNA single-strand breaks and DNA-protein cross-links. All measurements were higher in the four exposed groups compared with the external control group. DNA repair was impaired by As exposure, as indicated by the mRNA of O-6-methylguanine-DNA methyltransferase (MGMT), X-ray repair complementing defective repair in Chinese hamster cells 1 (XRCC1), and, to a lesser extent, by the mismatch repair gene hMSH2 mRNA. The expression of mutant-type p53 increased with aggravation of arsenicosis symptoms, whereas the expression of p16-INK4(p16) decreased. p53 mutated at a frequency of 30-17% in the carcinoma (n = 10) and precarcinoma (n = 12) groups. No mutation was found in p16, although deletion was evident. Deletion rates were 8.7% (n = 23) and 38.9% (n = 18) in noncarcinoma and carcinoma groups, respectively. CONCLUSIONS: The results showed that long-term As exposure may be associated with damage of chromosomes and DNA, gene mutations, gene deletions, and alterations of DNA synthesis and repair ability.     

砷中毒病区腐植酸对脂质过氧化反应的影响

目的探讨台湾乌脚病的病因。方法在体外进行了砷、腐植酸引发脂质过氧化反应的实验。用ＭＤＡ－ＴＢＡ比色法测定了从中国内蒙砷中毒地区和台湾乌脚病区井水以及贵州高砷煤中提取的腐植酸样品。结果试管内实验发现腐植酸能引起不饱和脂肪酸钠盐产生脂质过氧化反应,但作用较弱且不稳定。０．０５ｍｍｏｌ／Ｌ的Ｆｅ２＋能促进这一反应,而１ｍｍｏｌ／Ｌ的Ａｓ２Ｏ３却不能。各地腐植酸样品因来源、成分和结构不同,引起脂质过氧化反应的程度也不同,发现内蒙腐植酸引起脂质过氧化反应能力最强,其次是贵州样品、台湾样品,最后是商品腐植酸（购自美国Ａｌｄｒｉｃｈ公司）。实验还发现微量铁存在时,商品腐植酸引起的脂质过氧化反应是一个动力学过程,它同时具有分解脂质过氧化产物的能力。结论这一实验结果提示流行病学调查者关注乌脚病病区和高砷、高腐植酸地区环境中铁及其他过渡元素与腐植酸和砷的关系。     

Arsenic exposure and anemia in Bangladesh: a population-based study

OBJECTIVE: The purpose of this study was to examine the association between arsenic exposure and anemia, based on blood hemoglobin concentration. METHODS: Hemoglobin measures, skin lesions, arsenic exposure, and nutritional and demographic information were collected from 1954 Bangladeshi participants in the Health Effects of Arsenic Longitudinal Study. We used general linear modeling to assess the association between arsenic exposure and hemoglobin concentration, examining men and women separately. RESULTS: Arsenic exposure (urinary arsenic >200 microg/L) was negatively associated with hemoglobin among all men and among women with hemoglobin <10 d/L. Other predictors of anemia in men and women included older age, lower body mass index, and low intake of iron. Among women, the use of contraceptives predicted higher hemoglobin. CONCLUSIONS: The study suggests an association between high arsenic exposure and anemia in Bangladesh.     

Case studies--arsenic

Arsenic is found naturally in the environment. People may be exposed to arsenic by eating food, drinking water, breathing air, or by skin contact with soil or water that contains arsenic. In the U.S., the diet is a predominant source of exposure for the general population with smaller amounts coming from drinking water and air. Children may also be exposed to arsenic because of hand to mouth contact or eating dirt. In addition to the normal levels of arsenic in air, water, soil, and food, people could by exposed to higher levels in several ways such as in areas containing unusually high natural levels of arsenic in rocks which can lead to unusually high levels of arsenic in soil or water. People living in an area like this could take in elevated amounts of arsenic in drinking water. Workers in an occupation that involves arsenic production or use (for example, copper or lead smelting, wood treatment, pesticide application) could be exposed to elevated levels of arsenic at work. People who saw or sand arsenic-treated wood could inhale/ingest some of the sawdust which contains high levels of arsenic. Similarly, when pressure-treated wood is burned, high levels of arsenic could be released in the smoke. In agricultural areas where arsenic pesticides were used on crops the soil could contain high levels of arsenic. Some hazardous waste sites contain large quantities of arsenic. Arsenic ranks #1 on the ATSDR/EPA priority list of hazardous substances. Arsenic has been found in at least 1,014 current or former NPL sites. At the hazardous waster sites evaluated by ATSDR, exposure to arsenic in soil predominated over exposure to water, and no exposure to air had been recorded. However, there is no information on morbidity or mortality from exposure to arsenic in soil at hazardous waste sites. Exposure assessment, community and tribal involvement, and evaluation and surveillance of health effects are among the ATSDR future Superfund research program priority focus areas. Examples of exposures to arsenic in drinking water, diet and pesticide are given.     

A prospective study of the synergistic effects of arsenic exposure and smoking, sun exposure, fertilizer use, and pesticide use on risk of premalignant skin lesions in Bangladeshi men

Skin lesions are classic clinical signs of toxicity due to long-term exposure to arsenic, and they are considered precursors to arsenic-related skin cancer. The authors prospectively evaluated synergisms between effects of arsenic exposure and those of tobacco use, sun exposure, and pesticide and fertilizer use on incident skin lesions using risk factor data from 5,042 men from the Health Effects of Arsenic Longitudinal Study in Araihazar, Bangladesh, which recruited participants from October 2000 to May 2002. Discrete time hazard models were used to estimate measures of synergistic interactions on the additive scale. The authors observed significant synergistic effects between various measures of arsenic exposure and smoking and fertilizer use. The relative excess risks for the interactions between smoking status and arsenic exposure were 0.12 (95% confidence interval: 0.06, 0.19) for water arsenic and 0.11 (95% confidence interval: 0.05, 0.15) for urinary arsenic measures, respectively. Significant synergistic effects were also observed between fertilizer use and water arsenic (relative excess risk for the interaction = 0.06, 95% confidence interval: 0.01, 0.12). This is the first prospective study based on individual-level data that supports a role for smoking and certain occupational risk factors in modification of the effect of long-term arsenic exposure on skin lesions. Understanding differential arsenic susceptibility allows researchers to develop interventions to prevent the health consequences of this massive problem in the Bangladeshi population and beyond.     

Airborne arsenic and urinary excretion of arsenic metabolites during boiler cleaning operations in a Slovak coal-fired power plant.

Little information is available on the relationship between occupational exposure to inorganic arsenic in coal fly ash and urinary excretion of arsenic metabolites. This study ws undertaken in a coal-fired power plant in Slovakia during a routine maintenance outage. Arsenic was measured in the breathing zone of workers during 5 consecutive workdays, and urine samples were obtained for analysis of arsenic metabolites--inorganic arsenic (Asi), monomethylarsonic acid (MMA), and dimethylarsinic acid (DMA)--prior to the start of each shift. Results from a small number of cascade impactor air samples indicated that approximately 90% of total particle mass and arsenic was present in particle size fractions >/= 3.5 micron. The 8-hr time-weighted average (TWA) mean arsenic air concentration was 48.3 microg/m3 (range 0.17-375.2) and the mean sum of urinary arsenic (SigmaAs) metabolites was 16.9 microg As/g creatinine (range 2.6-50.8). For an 8-hr TWA of 10 microg/m3 arsenic from coal fly ash, the predicted mean concentration of the SigmaAs urinary metabolites was 13.2 microg As/G creatinine [95% confidence interval (CI), 10.1-16.3). Comparisons with previously published studies of exposure to arsenic trioxide vapors and dusts in copper smelters suggest that bioavailability of arsenic from airborne coal fly ash (as indicated by urinary excretion) is about one-third that seen in smelters and similar settings. Arsenic compound characteristics, matrix composition, and particle size distribution probably play major roles in determining actual uptake of airborne arsenic.     

中国砷中毒病区腐植酸样品致突变性研究

目的探讨砷中毒地区的腐植酸样品有无致突变性。方法用Ａｍｅｓ试验检测了从中国贵州省高砷煤、台湾乌脚病病区井水和内蒙古砷中毒病区井水中提取的天然腐植酸样品。结果贵州高砷煤中腐植酸在不加大鼠肝匀浆（＋Ｓ９）时回复突变系数为１．０２～０．８２ｒｅｖ／μｇ，在加入大鼠肝匀浆（＋Ｓ９）时回复突变数为１．５３～１．１２ｒｅｖ／μｇ。并有明显的剂量反应关系存在。结论贵州高砷煤中腐植酸对ＴＡ９８（移码突变型）菌株有较强的直接致突变性，台湾乌脚病病区井水中腐植酸对ＴＡ９８（－Ｓ９）有较弱的致突变作用，而内蒙腐植酸没有致突变作用。同时还研究了商品腐植酸、砷和铁的致突变性，发现单纯的砷、铁和商品腐植酸均无致突变作用，但是砷与腐植酸共同作用，在某一浓度时，不论有没有铁存在，对ＴＡ９８（－Ｓ９）都有微弱的致突变作用。以上各种样品对ＴＡ１００（±Ｓ９）（碱基取代型）菌株均不表现出致突变作用。     

燃煤型砷中毒流行因素的累积比数模型

为探讨燃煤型砷中毒流行因素的作用,用累积比数模型对１５１例不同程度砷中毒患者,１６例病区内对照、５３例病区外对照的暴露因素进行了分析。结果发现危险因素按作用大小依次是燃用高砷煤的年限、居室通风情况差、发砷及尿总砷负荷高、吸烟氟中毒;     

Phytoextraction and phytofiltration of arsenic

Arsenic, a ubiquitous contaminant in groundwater and soils, is currently drawing much public attention. Arsenic-contaminated soils can be cleaned up via phytoextraction-the use of plants to extract the arsenic from soil and transport it into aboveground tissues. Arsenic removal from polluted soils can be carried out using hyperaccumulator ferns like the Chinese brake fern Pteris vittata, which accumulates very high concentrations of the element in aboveground tissues. The capacity of the plant to take up large concentrations of arsenic, even at low levels in soil, illustrates efficient bioaccumulation. The possibility of using Pteris ferns to remove arsenic from water by phytofiltration has been proposed.     

Breast-feeding protects against arsenic exposure in Bangladeshi infants

BACKGROUND: Chronic arsenic exposure causes a wide range of health effects, but little is known about critical windows of exposure. Arsenic readily crosses the placenta, but the few available data on postnatal exposure to arsenic via breast milk are not conclusive. AIM: Our goal was to assess the arsenic exposure through breast milk in Bangladeshi infants, living in an area with high prevalence of arsenic-rich tube-well water. METHODS: We analyzed metabolites of inorganic arsenic in breast milk and infant urine at 3 months of age and compared them with detailed information on breast-feeding practices and maternal arsenic exposure, as measured by concentrations in blood, urine, and saliva. RESULTS: Arsenic concentrations in breast-milk samples were low (median, 1 microg/kg; range, 0.25-19 microg/kg), despite high arsenic exposures via drinking water (10-1,100 microg/L in urine and 2-40 microg/L in red blood cells). Accordingly, the arsenic concentrations in urine of infants whose mothers reported exclusive breast-feeding were low (median, 1.1 microg/L; range, 0.3-29 microg/L), whereas concentrations for those whose mothers reported partial breast-feeding ranged from 0.4 to 1,520 microg/L (median 1.9 microg/L). The major part of arsenic in milk was inorganic. Still, the infants had a high fraction (median, 87%) of the dimethylated arsenic metabolite in urine. Arsenic in breast milk was associated with arsenic in maternal blood, urine, and saliva. CONCLUSION: Very little arsenic is excreted in breast milk, even in women with high exposure from drinking water. Thus, exclusive breast-feeding protects the infant from exposure to arsenic.