Exposure of aboriginal people to methylmercury due to gold mining in the Amazon, Brazil

ＩｎｔｒｏｄｕｃｔｉｏｎＳｉｎｃｅｔｈｅｅａｒｌｙ 1980’ｓ,ｒａｐｉｄｉｎｃｒｅａｓｅｓｉｎｇｏｌｄｍｉｎｉｎｇａｃｔｉｖｉｔｉｅｓｕｓｉｎｇｍｅｒｃｕｒｙａｍａｌｇａｍａｔｉｏｎｔｅｃｈｎｉｑｕｅｉｎｍａｎｙｄｅｖｅｌｏｐｉｎｇｃｏｕｎｔｒｉｅｓｈａｓｂｅｅｎｏｎｅｏｆｔｈｅｍａｉｎｓｏｕｒｃｅｓｏｆｍｅｒｃｕｒｙｐｏｌｌｕｔｉｏｎ ,ｐａｒｔｉｃｕｌａｒｌｙｉｎｔｈｅＡｍａｚｏｎａｎｄｏｔｈｅｒｔｒｏｐｉｃａｌｒｅｇｉｏｎｓ(Ｍａｌｍ ,1990 ;Ｒａｍｅｌ,1996;Ｉｋｉｎｇｕｒａ,1996;Ｌａｃｅｒｄａ,…     

基于土壤汞形态归趋的健康风险评估方法

土壤汞污染是一个全球性关注问题,矿产资源开采、化工生产和燃煤发电等均造成了不同程度的土壤汞污染,合理评估汞污染场地的健康风险是场地开发再利用的关键.对土壤中汞的形态归趋研究总结表明,由于汞的特殊物理化学性质,并受土壤等环境因素的影响,导致其在土壤中具有复杂的化学形态和变化过程.汞在土壤中的不同化学形态归趋对其毒性效应、生物有效性和暴露途径产生显著影响.基于土壤汞总量的风险评估方法忽略了土壤中不同化学形态汞对毒性、生物有效性和暴露途径的影响,导致高估土壤汞污染的健康风险.针对基于土壤汞总量的风险评估存在的问题,提出了基于土壤汞形态归趋的土壤汞污染健康风险评估理论,并构建基于土壤汞形态归趋-有效剂量-健康效应的土壤汞污染的精细化风险评估技术体系框架:①土壤不同形态汞的测定与表征方法;②汞形态归趋预测模型;③暴露分析与暴露量计算;④有效剂量（生物可给性或生物有效性）测定;⑤风险表征;⑥基于不同形态汞的场地土壤污染风险筛选值和修复目标制定.该方法体系从理论上解决了传统基于土壤汞总量的风险评估方法存在的问题,实际应用中面临的主要问题和今后重点发展方向:①研发可商业化的土壤汞化学物组分分析仪及土壤汞蒸气的原位测定方法;②结合中国场地土壤特点,开展土壤中汞的形态归趋模拟的模型研究,弥补现阶段土壤汞化合物形态分析方法的欠缺;③研发和建立土壤汞的生物可给性和有效性的标准测试方法技术;④本土化的土壤汞筛选值的确定.      

Determination and assessment of total mercury levels in local, frozen and canned fish in Lebanon

Fish is an important constituent of the Lebanese diet. However, very little attention in our area is given to bring awareness regarding the effect of the toxicity of mercury (Hg) mainly through fish consumption. This study aimed to report analytical data on total mercury levels in several fish species for the first time in thirty years and to also made individuals aware of the presence and danger from exposure to mercury through fish consumption. Fish samples were selected from local Lebanese markets and fisheries and included 94 samples of which were fresh, frozen, processed, and canned fish. All values were reported as microgram of mercury per gram of fish based on wet weight. The level of mercury ranged from 0.0190 to 0.5700 μg/g in fresh samples, 0.0059 to 0.0665 μg/g in frozen samples, and 0.0305 to 0.1190 μg/g in canned samples. The data clearly showed that higher levels of mercury were detected in local fresh fish as opposed to other types thus placing consumers at higher risk from mercury exposure. Moreover, the data revealed that Mallifa (yellowstripe barracuda/Sphyraena chrysotaenia), Sargous (white seabream/Diplodus sargus), Ghobbos (bogue/Boops hoops), and shrimp (Penaeus sp.) were among the types containing the highest amounts of mercury. On the other hand, processed fish such as fish fillet, fish burger, small shrimp and crab are found to contain lower levels of mercury and are associated with lower exposure risks to mercury. Lebanese population should therefore, be aware to consume limited amounts of fresh local fish to minimize exposure to mercury.     

太湖营养状态对沉积物中总汞和甲基汞分布特征的影响

为探讨营养状态对太湖沉积物汞的分布及其甲基化的影响,以太湖不同营养水平的湖区为研究对象,采用PSA和GC-CVAFS方法,分别测定了沉积物总汞(THg)、甲基汞(MeHg)含量;另测定了沉积物有机质含量和水体总氮、总磷浓度.结果显示,太湖表层沉积物THg含量为32.30~150.28ng/g,均值为62.94ng/g,含量高低与营养化程度一致,其垂向分布主要受到人为活动和有机质的影响;MeHg含量为0.32~1.01ng/g,均值为0.51ng/g,不同营养水平的湖湾区MeHg含量差别不大,其分布受有机质的影响,高含量富集在表层,随深度的增加逐渐降低并趋于稳定;甲基化比率比较低主要是太湖水体溶解氧含量高抑制了甲基化过程.     

北京市饮用水源水重金属污染物健康风险的初步评价

对北京市城区8个区和郊区10个区、县120个样点的饮用水中Cu, Hg, Cd和As的浓度进行了调查研究,并应用目前美国环保局推荐的健康风险评价模型对北京市各区县饮用水中重金属所引起的健康风险作了初步评价.结果表明,城区8个区和郊区10个区、县重金属的平均浓度范围分别为Cu:0.81～6.96 μg·L^-1,Cd: 0.34～0.82 μg·L^-1,Hg: 0.10～0.74 μg·L^-1,As: 0.19～3.02 μg·L^-1.通过饮水途径所致健康风险中,As在通州区所引起的致癌风险最大(2.0×10^-5·a^-1),Cd在昌平区的致癌风险最大(2.3×10^-6·a^-1), 但均低于国际辐射防护委员会(ICRP)推荐的通过饮水途径最大可接受风险水平(5×10^-5·a^-1);在北京市通过饮水途径引起的非致癌健康风险中,Hg的风险最大,Cu次之,但是两者风险水平均在10-8～10^-9·a^-1,远低于ICRP推荐的最大可接受风险水平.     

Transport and fate of mercury under different hydrologic regimes in polluted stream in mining area

Seepage from Hg mine wastes and calcines contains high concentrations of mercury (Hg). Hg pollution is a major environmental problem in areas with abandoned mercury mines and retorting units. This study evaluates factors, especially the hydrological and sedimentary variables, governing temporal and spatial variation in levels and state of mercury in streams impacted by Hg contaminated runo . Samples were taken during di erent flow regimes in theWanshan Hg mining area in Guizhou Province, China. In its headwaters the sampled streams/rivers pass by several mine wastes and calcines with high concentration of Hg. Seepage causes serious Hg contamination to the downstream area. Concentrations of Hg in water samples showed significant seasonal variations. Periods of higher flow showed high concentrations of total Hg (THg) in water due to more particles being re-suspended and transported. The concentrations of major anions (e.g., Cl??, F??, NO3?? and SO4 2??) were lower during higher flow due to dilution. Due to both sedimentation of particles and dilution from tributaries the concentration of THg decreased from 2100 ng/L to background levels (< 50 ng/L) within 10 km distance downstream. Sedimentation is the main reason for the fast decrease of the concentration, it accounts for 69% and 60% for higher flow and lower flow regimes respectively in the upper part of the stream. Speciation calculation of the dissolved Hg fraction (DHg) (using Visual MINTEQ) showed that Hg(OH)2 associated with dissolved organic matter is the main form of Hg in dissolved phase in surface waters in Wanshan (over 95%).     

Mercury in sediments and vegetation in a moderately contaminated salt marsh (Tagus Estuary, Portugal)

Depth variations of total mercury (Hg) and methylmercury (MeHg) concentrations were studied in cores from non-colonized sediments, sediments colonized by Halimione portulacoides, Sarcocornia fruticosa and Spartina maritima and belowground biomass, in a moderately contaminated salt marsh (Tagus Estuary, Portugal). Concentrations in belowground biomass exceeded up to 3 (Hg) and 15 (MeHg) times the levels in sediments, and up to 198 (Hg) and 308 (MeHg) times those found in aboveground parts. Methylmercury in colonized sediments reached 3% of the total Hg, 50 times above the maximum values found in non-colonized sediments. The absence of correlations between total Hg concentrations in sediments and the corresponding MeHg levels suggested that methylation was only dependent on the environmental and microbiological factors. The analysis of belowground biomass at high-depth resolution (2 cm) provided evidence that Hg and MeHg were actively absorbed from sediments, with higher enrichment factors at layers where higher microbial activity was probably occurring. The results obtained in this study indicated that the biotransformation of Hg to the toxic MeHg could increase the toxicity of plant-colonized sediments.     

典型煤矿城市居民区室内灰尘中汞污染季节差异及其健康风险

为了解典型煤矿城市居民区室内灰尘中汞(Hg)含量的季节差异及其健康风险,采集淮南市居民区室内灰尘样品116个(每个季节29个),利用AFS-820测定灰尘中Hg含量.结果显示,淮南市居民区不同季节室内灰尘中Hg平均含量均超出了土壤背景值,春、夏、秋、冬4个季节室内灰尘中Hg平均含量分别是背景值的21、5、6、27倍,冬季和春季室内灰尘中Hg含量显著高于夏季和秋季.淮南市居民区室内灰尘中Hg主要受燃煤影响,尤其冬季和春季.Hg富集水平和污染程度的季节差异规律均表现为:冬季春季秋季夏季,且4个季节室内灰尘中Hg的污染程度均超过了中度污染.Hg的4种暴露途径的暴露量和健康风险均呈现出:Hg蒸汽吸入手-口摄入皮肤接触呼吸吸入,Hg蒸汽吸入和手口摄入暴露途径的暴露量和非致癌风险要高于其他途径3~4个数量级,且儿童和成人4个季节的总非致癌风险总和达到了0.248和0.135,存在着一定潜在风险.     

武汉市城郊蔬菜种植区重金属积累特征及健康风险评价

为了解武汉市城郊蔬菜种植区土壤-蔬菜-地下水系统中重金属积累造成的健康风险,在武汉市城郊5个辖区内采集土壤、蔬菜、地下水样品,分析其中As、Cd、Hg、Pb 4种重金属的含量及积累特征;采用健康风险评价模型,并考虑区域人群特点及工作特性等进行参数优化,对研究区人群在不同暴露途径、不同暴露介质下的健康风险进行评价. 结果表明:土壤重金属单项污染指数呈Cd>As>Hg>Pb的分布特征,Cd、Hg的土壤累积指数分别为6.51、2.00;叶菜类、瓜果类、根茎类和豆类4个类别新鲜蔬菜中,叶类蔬菜的w(Pb)显著高于其他蔬菜种类,瓜果类的w(As)和w(Hg)相对较高,根茎类的w(Cd)最高;蔬菜-土壤、地下水-土壤系统中同种重金属元素含量存在较高的相关性;3种暴露介质下的健康风险水平表现为蔬菜>地下水>土壤,经口暴露风险占总个人年风险的98.90%;总个人年风险为1.97×10-5 a-1,其中致癌年风险占99.60%,该总个人年风险未超出国际辐射防护委员会(ICRP)推荐的最大可接受风险值(5.0×10-5 a-1),但要防止土壤-蔬菜-地下水系统的进一步污染.      

贵州省典型铅锌矿区居民血液总汞和甲基汞暴露及健康风险模型预测评估

汞是铅锌矿石的常见伴生元素,铅锌冶炼活动会给当地居民带来潜在汞暴露风险.为了解铅锌矿区居民血液汞暴露及健康风险,选择贵州省赫章县为研究区域,以贵阳市为对照区,分别采集居民血液样品418和118份,利用冷原子荧光法测定其总汞和甲基汞含量,结合年龄和性别分析血液总汞与甲基汞含量特征,估算育龄期妇女头发甲基汞含量并进行甲基汞暴露致新生儿IQ（智商）损失评估,利用单区室PBPK（生理药代动力学）模型预测居民甲基汞ADI（日均摄入量）.结果表明:①铅锌矿区（赫章县）和对照区居民血液总汞含量几何均值分别为（3.11±5.05）和（1.83±1.19）μg/L,范围分别为0.63~54.26和0.46~11.88 μg/L,分别有21.5%和0.85%的血液样本总汞含量超过人体血液总汞安全限值（5.8 μg/L）.②铅锌矿区成年居民和0~6岁儿童血液总汞含量分别为（2.80±3.85）和（2.49±2.08）μg/L,分别有77和7人血液总汞含量超过5.8 μg/L,超标率分别为24.37%和10.61%,存在潜在总汞暴露风险.③斯皮尔曼相关性分析显示,铅锌矿区居民血液总汞和甲基汞含量分别与年龄（R=0.108,P < 0.05）和性别（R=-0.185,P < 0.05）相关,老年人较其他年龄段人群总汞暴露的风险更高,其血液总汞含量达（5.29±5.03）μg/L;男性血液甲基汞含量〔（0.24±0.32）μg/L〕高于女性〔（0.18±0.22）μg/L〕.④蒙特卡洛模型模拟结果显示,铅锌矿区和对照区育龄妇女头发甲基汞平均含量分别为（0.07±0.11）和（0.11±0.13）mg/kg,范围分别为0~11.81和0~5.74 mg/kg,其中铅锌矿区2.27%的育龄期妇女头发甲基汞含量超过发汞临界值（0.58 mg/kg）,导致IQ评分为70~70.18分范围内的约0.05%的婴儿从IQ正常转变为MMR（轻度智力低下）.⑤单区室PBPK模型预测表明,铅锌矿区和对照区居民甲基汞日均摄入量分别为（0.005±0.006）和（0.007±0.008）μg/kg,分别有0.082%和0.013%的居民甲基汞日均摄入量超过RfD（参考剂量值,0.1 μg/kg）.研究显示:铅锌矿区成年居民和0~6岁儿童血液总汞含量高于国内其他地区,男性血液甲基汞含量明显高于女性;铅锌矿区约2.27%的育龄期妇女头发甲基汞含量超过发汞临界值,可致IQ评分在70~70.18分范围内的约0.05%的婴儿从智力正常转变为MMR;铅锌矿区居民甲基汞非致癌风险高于对照区.      

汞污染地块风险全生命周期管控技术体系研究

风险全周期管理是推进汞污染地块风险管控,有效实现地块安全可控的重要方式.在《关于汞的水俣公约》全球履约背景下,为有效提升汞污染地块的风险预防与管控能力,该文对汞污染地块风险管控技术体系进行了深入研究.在深入分析污染地块健康风险全生命周期特征的基础上,围绕地块风险源头-暴露途径-环境受体3个核心风险要素,并结合国内外技术研发与工程示范经验,构建出适用于此类污染地块的风险全周期分类管控技术体系.该体系根据土壤与地下水风险管控标准评价地块污染水平,并结合地块敏感目标和暴露途径等暴露情景对地块进行分类管控决策.通过对工程修复、风险管控、制度控制等进行多技术有机耦合,可实现对汞污染地块全方位、多角度、系统化的风险管理,即在风险产生、风险发展与风险消褪的各个环节,分别施以源头预防、过程控制及长期管理措施,有效遏制地块新增风险的基础上,实现污染地块风险的安全可控.该技术体系存在如下特征:1)基于风险的管理决策可以反映地块管理的科学内涵;2)分类风险管控策略可以有效节约成本,实现最大的管控净效益;3)以全生命周期管理为基本理念,实现“源头-过程-末端”的全流程风险控制.     

污灌区稻田汞污染特征及健康风险评价

选择天津北排污河灌区作为研究区域,调查了土壤和水稻总汞和甲基汞的含量及分布特征,评估污灌区稻米食用汞暴露风险,并对污灌区土壤-稻米甲基汞的影响因素进行了初步分析.结果表明,1.调查的29个污灌区稻田,土壤总汞含量为(367.04 ± 129.36) μg/kg,显著高于区域土壤Hg背景值73 μg/kg,甲基汞含量为(0.87 ± 0.77) μg/kg;水稻各部位总汞含量依次为稻叶 > 稻根 > 稻茎 > 稻米,稻米总汞含量为(12.80 ± 5.14) μg/kg,甲基汞含量依次为稻米 > 稻根 > 稻茎 > 稻叶,稻米对甲基汞具有很强的富集能力,甲基汞含量为(2.09 ± 1.20) μg/kg,甲基化率均值超过10%.污灌区稻米总汞每周摄入量为0.068~1.25μg/(kg·bw),甲基汞每周摄入量为0.0095~0.49μg/(kg·bw),污灌区稻米总汞及甲基汞暴露对居民健康风险总体仍在安全阈值内,但个别汞污染较严重地块甲基汞暴露风险值得高度关注.土壤甲基汞含量仅与土壤总汞含量及黏粒含量的相关性达到显著性水平,稻米甲基汞含量与土壤总汞含量、土壤甲基汞含量、稻米总汞含量及黏粒含量的相关性达到显著性水平.     

北京市凉凤灌区小麦重金属含量的动态变化及健康风险分析 --兼论土壤重金属有效性测定指标的可靠性

通过对北京市凉凤灌区小麦籽粒及其相对应土壤样品的调查发现,小麦籽粒中的Ni、Pb、Zn超标率分别为38.1%、28.6%、4.8%;Hg、Cd虽然未发现超标现象,但也有部分样品接近国家食品卫生标准（GB2762-1994和GB 15201-1994）;与1976年的调查结果相比,在过去的30年中,小麦籽粒中Hg、Pb、Cu含量呈显著增加的趋势.研究结果表明,北京凉凤灌区的小麦存在Hg、Pb、Zn等污染的潜在风险.无论是测定的土壤重金属全量,还是测定的土壤重金属的可提取态含量,都与小麦籽粒的重金属含量无显著的相关性.因此,在评价土壤重金属污染是否对农作物（小麦籽粒）影响时,采用目前通用的土壤可提取态重金属并不一定会优于土壤重金属全量.     

Benzene and lead exposure assessment among occupational bus drivers in Bangkok traffic

IntroductionAirpollutionproblemsasaresultoffastgrowthinthetotalnumberofvehiclesinurbancitiesareontheincrease .PreliminaryepidemiologicalexposureassessmentsuggestthatthedetrimentaleffectofairpollutiongeneratedbyvehiculartrafficindevelopingcitieslikeBangkok…     

乌江流域大气降雨中不同形态汞的时空分布

2006年1～12月测定了乌江流域5个水库库区大气降雨中不同形态汞的浓度.结果表明,总汞、溶解态汞、颗粒态汞、活性汞、甲基汞的浓度范围分别为7.49～149.13ng·L-1、1.23～10.02ng·L-1、5.76～141.92ng·L-1、0.56～2.94ng·L-1、0.082～0.821ng·L-1.降雨中颗粒态汞为主要形态,约占总汞比例的67.6%～96.1% (平均87%),活性汞、甲基汞占总汞的比例分别为5.1%和0.68%.除活性汞外,其它形态汞的浓度存在明显的季节变化趋势,冬春季的浓度明显高于夏秋季,而不同形态汞的空间分布特征不明显.降雨中汞的浓度主要受降雨量及燃煤等人为活动的影响.     

Comparison of in vitro digestion methods for determining bioaccessibility of Hg in rice of China

Rice consumption can be a major pathway for mercury(Hg) exposure, which can cause health hazards to Chinese residents. To accurately assess the potential health risks, the bioaccessibility of Hg in rice samples collected at background and Hg-contamination sites was examined using four in vitro methods. The results showed that 50% of the total mercury(THg) was bioaccessible in the studied rice samples. The THg bioaccessibility in the rice samples collected at the Hg-contaminated site was higher than that observed at the background area. The bioaccessibility of arsenic(As) and cadmium(Cd) was also evaluated for comparison of the four in vitro methods used in this study. The Physiologically Based Extraction Test was found to be the most accurate method based on the consistency of the results compared to those reported in previous studies. The estimated daily intakes of THg via rice consumption using the bioaccessibility data were found to meet the recommendation value set by the JECFA and the WHO in both sites. However, the potential health risk was not negligible at the Hg-contaminated sites, due to the high THg concentration and bioaccessibility in the rice samples.     

交通污染暴露对DNA甲基化的影响

探讨交通污染现场暴露对DNA甲基化的影响.30只8周龄Wistar大鼠按随机数字表法随机分5组,每组6只.其中3组分别在隧道(高暴露组)、路口(中暴露组)、校园(对照组)暴露7 d,另外2组分别在隧道暴露14 d/28 d.在暴露过程中检测3个暴露地点PM_(10)、NO_2的浓度.暴露实验分别在春季、秋季各进行一次.暴露结束后,焦磷酸测序法检测肺组织和血液中DNA(p53、MGMT、MAGE-A4)甲基化水平,并分析比较不同暴露组间DNA甲基化水平的差异.结果表明,PM_(10)、NO_2浓度均为隧道(高暴露组)路口(中暴露组)校园(对照组),差异具有统计学意义.秋季暴露7 d后,与对照组相比,肺组织中p53(P_(路口)=0.016;P_(隧道)=0.019)、MGMT(P_(路口)=0.002;P_(隧道)=0.003)启动子甲基化水平显著降低,随着暴露时间的增加,甲基化水平进一步降低;MAGE-A4启动子区处于高度甲基化状态,在肺组织和血液中,均未发现MAGE-A4启动子甲基化水平在三暴露组间存在显著的统计学差异.7d暴露对肺组织中DNA甲基化水平的影响更大,但随着暴露时间的增加,肺组织和血液中DNA甲基化水平改变模式趋于一致.Spearman相关分析结果显示,在肺组织中,PM_(10)和p53甲基化水平呈负相关关系(r=-0.347;P=0.038);NO_2和p53、MGMT、MAGE-A4甲基化水平均存在负相关(r值分别为-0.482、-0.444、-0.346,P值均0.05).在血液中,MAGE-A4甲基化水平与PM_(10)、NO_2均呈正相关(r值分别为0.395、0.431,P值均0.05).交通污染暴露会引起p53、MGMT启动子低甲基化.     

大连市居民头发典型重金属富集特征研究

测定了大连市居民102份头发样品中Pb、Cd、Hg、As等重金属含量,评估了其暴露风险,并对头发中重金属的含量与年龄、性别的关系进行了分析.结果表明,大连市居民头发中Pb、Cd、Hg、As含量均低于中国居民头发中重金属的建议正常值上限,4种重金属暴露风险较低.男性头发中Cd、Pb和As的平均含量明显高于女性(p0.05),其中As平均含量差异达到极显著水平(p0.01).PCA分析显示样本分布集中在第一排序轴和第二排序轴中间,表明性别并不是影响头发中重金属含量的主要因素.19～35岁年龄组居民头发中Cd和Pb含量最高,且均与56～75岁年龄组呈现显著差异(p0.05);As和Hg在56～75岁年龄组居民头发中含量最高,与其它组比较均达到了显著水平(p0.05).PCA和Pearson分析表明4种重金属间相关性较好,大连市居民对4种重金属暴露途径基本相同.     

Health implication among occupational exposed workers in a chromium alloy factory, Thailand

IntroductionNationalStatisticalOffice ,Thailand (NSO ,2 0 0 0 )reportedthattheneedformetalmanufacturingindustriesandassociatedproductionsectorhasincreasedatanextremelyrapidrate ,especiallyinthecentralpartofThailand .Itisestimatedthattherearemorethan 10 0 …     

Do concentrations in eggs and liver tissue tell the same story of temporal trends of mercury in high Arctic seabirds?

Mercury(Hg) remains a key contaminant of concern in Arctic biota, and monitoring of Hg concentrations in seabird tissues will be an effective approach to track the effects of implementing the Minamata Convention. We examined trends in total Hg(THg) in liver and egg tissues of two Arctic seabirds, thick-billed murres(Uria lomvia) and northern fulmars(Fulmarus glacialis), between 1976 and 2013 to assess whether both tissues showed similar patterns of Hg change. Hepatic THg was consistently higher than egg THg, and both species had similar egg THg concentrations, but fulmars had higher hepatic THg than murres.Murre THg concentrations showed more relative variation through time than fulmars.We suggest that egg THg better reflects exposure of birds to THg in local, Arctic prey,whereas liver THg may incorporate longer term, year-round THg exposure. Additional analysis of THg distribution in Arctic seabirds post-laying would help inform interpretation of long-term trends.