Metal Contamination and Infiltration into the Soil at Refuse Dump Sites in Awka,Nigeria

Awka has been the site of increased human activities since it became a state capital in 1991. Because refuse dumps have hitherto been a disregarded environmental menace in Nigeria, the authors sought to find out how much of the current environmental metal pollutant load comes from refuse dumps. They investigated the metal contamination of the refuse dumps in Awka. The authors collected four soil samples (from the surface and from depths of 0.45 m, 0.90 m, and 1.35 m) from 5 dumpsites digested with nitric acid and perchloric acid, and they analyzed iron, sodium, arsenic, lead, magnesium, potassium, cobalt, zinc, nickel, copper, chromium, and cadmium by using an atomic absorption spectrophotometer. Sites A and C showed the highest levels of arsenic (2300 mg/kg) and lead (2467 mg/kg), respectively. Site D had highest level of both iron (72,200 mg/kg) and sodium (3561 mg/kg), whereas Site E had the lowest level of lead (572 mg/kg). The metal levels exceed the limits set forth by the US Environmental Protection Agency. This study suggests that the refuse dumps in Awka may increase the level of environmental heavy metals in Nigeria.     

北京市环卫工人作业环境空气细菌污染调查

本文调查了北京市垃圾转运场、医院内垃圾站、平房居民垃圾站、楼旁居民垃圾站、清洁车辆修配厂等各种环卫工人作业环境的空气细菌污染状况。结果表明环卫工人作业环境的空气细菌污染是严重的(>4000个/m~3)。大多以春季空气细菌数最高,垃圾转运场夏季细菌数最高,医院内垃圾站四季中无明显差异。     

电子线路板粉末浸出液重金属含量分析及其饲养斑马鱼前后鱼体内镍铬水平的变化

目的通过分析电子线路板粉末中主要重金属成分的含量及其浸出液中重金属含量,分析其中可溶性重金属盐类所占的比重,同时通过动物实验初步探讨该废弃物溶出液饲养斑马鱼后镍镉在斑马鱼体内变化的情况。方法通过原子吸收分光光度法分析并对比电子线路板粉末和浸出液中铜、铅、锌、镉、镍、铬、铁、锰的含量,初步分析该粉末中重金属的溶出情况及对水体可能的影响。通过对不同剂量浸出液饲养的斑马鱼体内镍铬含量的分析,探讨其在斑马鱼体内变化的情况。结果电子线路板粉末中含量最高的前3位金属分别是铜、铅和铁,分别达64.1、55.6和25.8 mg/kg;金属铬未被检出。浸出液中含量最高的前3位金属分别是铜、锰和镉,其含量分别达1.440、0.322和0.088 mg/L。在实验室饲养斑马鱼中,虽然对照组、低剂量组和中剂量组检测结果有一些不同,但其差异无统计学意义。结论电子线路板拆解废弃物中铜、锰、镉溶出量较高,应在现场监测中重点关注。用一定浓度的浸出液饲养斑马鱼体,其体内的镍铬水平基本无变化。     

Heavy metals other than lead in flaked paints from buildings in Eastern Nigeria

Cadmium, chromium, iron, zinc, and copper levels of flaked paints collected from fifty buildings of four major cities - Enugu, Onitsha, Aba, and Port Harcourt in Eastern Nigeria were studied. Fifty samples of the flaked paints were ground with laboratory pestle and mortar, 2 g of fine ground paints that could pass through a 0.5-mm sieve were digested with 15 ml concentrated nitric acid and perchloric acid at a ratio of 1:1 and analyzed for cadmium, chromium, iron, zinc and copper using atomic absorption spectrophotometer 500. Cadmium ranged from 9.032 +/- 0.000 to 10.575 +/- 0.000 and 6.845 +/- 0.000 to 10.028 +/- 0.002 mg/kg in Enugu and Onitsha, respectively. In Aba and Port Harcourt, the levels of cadmium ranged 7.464 +/- 0.002-9.343 +/- 0.002 and 7.293 +/- 0.002-9.395 +/- 0.000 mg/kg, respectively. Chromium levels were significantly lower in Enugu (range 0.940 +/- 0.000-12.793 +/- 0.002 mg/kg) when compared with the values from other cities namely Onitsha (range 1.613 +/- 0.002-15.140 +/- 0.000 mg/kg), Aba (range 15.206 +/- 0.000-39.215 +/- 0.000 mg/kg) and Port Harcourt (range 33.118 +/- 0.002-55.418 +/- 0.002 mg/kg). The highest levels (mg/kg) of iron (11,908.150 +/- 0.000), zinc (31.508 +/- 0.002) and copper (7.588 +/- 0.002) were seen in buildings from Enugu aged 11 years and above. The iron level (mg/kg) ranged from 1391.750 +/- 0.000 to 10,476.845 +/- 0.000, 1450.176 +/- 0.000 to 11,580.750 +/- 0.000 and 3314.913 +/- 0.002 to 8162.333 +/- 0.002 in Onitsha, Aba, and Port Harcourt, respectively. Zinc levels were significantly lower in Onitsha than in Aba and Port Harcourt. Age of building did not seem to affect the levels of these metals namely iron, zinc and copper from these cities. This study shows that flaked paints increase the environmental heavy metal burden in Nigeria.     

Study of aluminium and lead in some traditional Omani dishes

Because of the recent interest on the aluminium content of foods cooked in aluminium saucepans and the association between aluminium and lead and many toxic symptoms and disease, information about the source of exposure of man to these metals specially from food and drinks are required. Thirty four of the most commonly consumed Omani dishes were analyzed for their aluminium and lead content, in order to determine the level of contamination and to estimate the approximate oral intake of each metal. The level of aluminium in the studied dishes was in the range between 0.98 and 16.53 mg/kg with a mean 5.4 mg/kg. The highest level of aluminium was found in fish dishes (9.03 mg/kg) and meat and poultry dishes (7.66 mg/kg). The effect of using aluminium pans on the metal level was also studied in some foods. The effect varies from slight increase in case of frying or cooking of fish to a significant increase in case of baking rakal bread on aluminium flat pan. The level of lead in the studied dishes ranged between 0.026 and 1.75 mg/kg with a mean of 0.32 mg/kg. Salted fish contained the highest level of lead (0.57 mg/kg). The approximate daily intake, calculated on the base of the serving quantities, was found to be within the acceptable daily or weekly intake recommended for each metal.     

海南省245份甲壳类海产品中四种重金属污染分析

目的 了解海南部分沿海区域甲壳类海产品中重金属的污染状况.方法 分别在2015、2017和2019年从昌江县、文昌市、儋州市和万宁市农贸市场和超市等随机采集6种甲壳类样本共245份,选择电感耦合等离子体质谱仪对样本中镉、铅、砷、汞的含量进行分析,采用单因子污染指数(Pi)和内梅罗综合污染指数(P综)法来评价重金属的污染...     

Effect of Bauxite Mineralized Soil on Residual Metal Levels in Some Post Harvest Food Crops in Jamaica

The concentrations of nine residual metals in some Jamaican foods were determined using inductively coupled plasma mass spectrometry technique. Cadmium concentration was highest in yellow yam (0.21 mg/kg). Sweet potato had the highest concentrations of lead (0.31 mg/kg), arsenic (0.70 mg/kg) and mercury (0.35 mg/kg). Samples from Grove Place exceeded the regulatory limits of 0.1 mg/kg for cadmium, lead and arsenic and 0.05 mg/kg for mercury. Significant correlations were found between soil and agricultural produce concentrations for cadmium and lead (r² ≥ 0.5). These results suggest that the elements were available in soluble forms in the soil for absorption by food crops.     

酒泉戈壁设施蔬菜重金属含量的测定及健康风险评估

目的 了解酒泉市戈壁设施种植的番茄、葫芦、黄瓜、辣椒、豆角中铅、砷、汞、镉的污染状况,评估人体摄入后的健康风险。方法 利用国家标准检验方法,在酒泉市总寨和东洞戈壁农业产业园区采集检测274份主栽蔬菜中铅、砷、汞、镉含量,结合单因子污染指数和内梅罗污染指数法对蔬菜受重金属污染的程度进行评价,利用靶标污染系数法对蔬菜中重金属对人体的健康风险进行评估。结果 274份蔬菜中铅、砷、汞和镉的含量范围分别为0～0.050 1 mg/kg、0～0.053 8 mg/kg、0～0.001 0 mg/kg和0～0.048 8 mg/kg,平均含量分别为0.010 3、0.010 3、0.000 2和0.008 7 mg/kg,均未超出国家标准规定的食品中污染物限量。5种蔬菜中4种重金属的污染指数均低于0.7,靶标危害系数均小于1。结论 酒泉市总寨和东洞戈壁农业产业园区主栽的5种蔬菜受铅、砷、汞、镉污染程度较轻,属于清洁水平,处于安全级别,膳食摄入风险较低。对比其它地区蔬菜,酒泉戈壁设施蔬菜中重金属含量总体不高,与有机设施蔬菜基地结果接近。     

苏北某地区小龙虾重金属含量与养殖水体的相关性分析

目的了解小龙虾及其养殖水体常见重金属的含量及分布,探讨小龙虾重金属污染与养殖环境的关系。方法选择苏北某地区分别采集各点成年小龙虾及养殖塘水样,按国标采用石墨炉原子吸收或原子荧光法检测样品中砷、铅、汞、镉的含量,分析其在体内的分布及与养殖水体的相关性。结果小龙虾体内砷、铅、汞、镉检出率分别为100.0%、55.8%、56.7%和92.5%,含量超0.5mg/kg浓度水平的比重分别为34.2%、5.0%、10.0%及0。养殖塘水中铅、镉均未检出,砷、汞检出率为60.0%和20.0%,砷、汞超标率为20%和12%。小龙虾头部对砷、铅、镉的蓄积远高于尾部。养殖塘水砷和小龙虾尾砷、水汞与小龙虾尾汞之间存在相关关系。结论该地区小龙虾以砷、汞的含量最高,头部（虾黄）高于尾部（肌肉）,重金属含量与其养殖水体有关。     

Trace metal content and estimated daily human intake from chicken eggs in Ibadan, Nigeria

A total of 151 chicken eggs and 4 local chicken feeds purchased directly from the poultry farms, at the local markets, and along the roadsides of Ibadan, Nigeria, were analyzed for lead, cadmium, copper, iron, nickel, zinc, and cobalt by carbon graphite atomic absorption spectrophotometry. The authors found strong, positive correlations between the levels of metals in the feeds and the corresponding levels of metals in the eggs. The overall average concentrations (mg/kg) of each metal in eggs were as follows: lead, 0.59; cadmium, 0.07; copper, 0.78; iron, 23.20; nickel, 0.03; zinc, 13.75; and cobalt, 0.01. The average estimated daily intake of lead, cadmium, copper, and iron per person was 19.5 microg, 2.4 microg, 25.6 microg, and 762.3 microg, respectively, whereas daily intakes of nickel, zinc, and cobalt were 0.9 microg, 452.1 microg, and 0.2 microg per person. The concentrations of some metals in eggs from this study did not differ appreciably from levels determined in eggs from other countries; concentrations of lead and cadmium in the current study, however, were comparatively greater than levels found in other countries. Therefore, the estimated daily intakes of lead and cadmium in this region slightly exceeded the normal reported daily intakes of lead and cadmium from eggs in some other countries.     

2012-2013年江苏省东海县食品污染物理化指标监测结果分析

目的了锵江苏省东海县2012--2013年食品污染物中铅、镉、汞、砷、铝的污染状况,为食品污染物检测和食品安全的危险性评价提供科学依据。方法按照《江苏省食品安全风险监测方案》的要求,对随机抽取的5大类共95份样品进行理化项目的检测,并将监测结果进行统计分析。结果检测5大类食品95份,汞的检出率最高,为90．53％,其中肉类中的汞含量最高,均值为0．0349mg／kg。其次是镉,检出率为87．37％;水海产品中镉的平均含量为0．0320mg／kg。铅,砷和铝的检出率分别为78．95％,22．11％,70．00％。结论不同种类食品受重金属的污染程度不同,应重点加强对有重金属汞污染的食品的监督管理,以提高食品安全性。     

Greenhouse study on the phytoremediation potential of vetiver grass, Chrysopogon zizanioides L., in arsenic-contaminated soils

The purpose of this greenhouse study was to assess the capacity of vetiver grass to accumulate arsenic from pesticide-contaminated soils of varying physico-chemical properties. Results indicate that vetiver is capable of tolerating moderate levels of arsenic up to 225 mg/kg. Plant growth and arsenic removal efficiency was strongly influenced by soil properties. Arsenic removal was highest (10.6%) in Millhopper soil contaminated with 45 mg/kg arsenic, which decreased to 4.5 and 0.6% at 225 and 450 mg/kg, respectively. High biomass, widespread root system and environmental tolerance make this plant an attractive choice for the remediation of soils contaminated with moderate levels of arsenic.     

2018—2021年天津市市售螃蟹中四种重金属污染状况及评价

目的 了解天津市市售螃蟹中重金属污染水平及其在螃蟹体内分布,为水产品的重金属污染防控提供依据。方法 根据《国家食品污染物及有害因素风险监测工作手册》要求,在天津市范围内采用随用机抽样方法,采集市售代表性螃蟹样品275份。按照国家标准检测方法对其中的铅、镉、汞、砷含量进行检测,并采用单因子污染评价指数法评价污染程度。结果 275份螃蟹样品中四种重金属元素总体含量水平依次为镉(0.058 mg/kg)、铅(0.056 mg/kg)、无机砷(0.027 mg/kg)、甲基汞(0.019 mg/kg)。四种元素中镉超标率最高(49.09%),无机砷次之(4.29%),铅最低(0.48%);海水蟹中镉、无机砷超标率(75.71%、7.48%)高于淡水蟹(22.66%、0.97%);蟹黄/蟹膏中镉超标率(46.91%)高于胸肌(8.36%)、腿肌(3.27%)。单因子污染指数评价结果显示,海水蟹蟹黄/蟹膏中镉处于重度污染水平(Pi = 5.12),胸肌中镉(Pi = 0.25)及蟹黄/蟹膏中无机砷(Pi = 0.22)处于轻度污染水平;淡水蟹蟹黄/蟹膏中镉(Pi = 0.44)处于轻度污染水平。结论 天津市市售螃蟹中铅、镉、甲基汞、无机砷均存在不同程度的污染,镉、无机砷污染较为严重,建议加强监管并引导居民合理膳食。     

Arsenic, cadmium, lead and mercury in king bolete Boletus edulis and tolerance limits

In the article are reviewed and discussed available data on arsenic, cadmium, lead and mercury content of the fruiting bodies of king bolete. The values of cadmuim concentration of the fruiting bodies of king bolete collected from the areas unpoluted with metals and metaloids in Poland and other European countries usually are greater than an actual tolerance limits set by E.U. law for 0.2 mg/kg wet weight in cultivated mushrooms. Analogically, as is for cadmium also content of lead to be sometimes greater than tolerance limit of 0.3 mg/kg w.w. set in EU for cultivated mushrooms. The fruiting bodies of king bolete usually are also relatively rich in mercury at concentration much greater when compared to tolerance limit set earlier in Poland (in E.U. there is no tolerance limit for mercury in mushrooms). In the case of cadmium it can bee agreed, that this element content of pooled samples of the fruiting bodies of king bollete collected from unpolluted regions usually will not exceed a value of 20 mg/kg d.m., while at polluted areas will exceed a value of 20 mg/kg d.m. In the case of mercury it can bee agreed, that this element content of pooled samples of the fruiting bodies of king bollete collected from unpolluted regions usually will not exceed a value of 5 mg/kg d.m., while at polluted areas will exceed a value of 5 mg/kg d.m. In the case of lead it can be agreed, that this element content of some percent of pooled samples of the fruiting bodies of king bolete collected from unpoluted regions will sometimes exceed an actual the EU tolerance limit of 0.3 mg/kg w.w. as set only or cultivated mushrooms. In the case of arsenic it can be agreed, that total arsenic contant of some percent of pooled samples of the fruiting bodies of king bolete collected from unpoluted regions will exceed value of 0.50 mg/kg d.m.     

华北地区二十三种中药材中重金属及有害元素基线调查及参考限量标准建立

目的了解中国华北地区中药材重金属及有害元素的基线水平,制定适合国情并与国际接轨的参考限量标准。方法采用本实验室建立的植物药材中重金属及有害元素检测方法,完成了华北地区23种254份植物性中药材中铅、镉、汞和砷的测定。结果各类植物药材中铅、镉、汞和砷的含量分别为(1·78±1·98)、(0·17±0·24)、(0·04±0·06)和(0·72±0·69)mg/kg。在制定植物性中药材中重金属铅、镉、汞和砷的限量标准的过程中要充分考虑到人体经口摄入的各种食物、饮料及水等可食的物质中这些有害物质的摄入量。目前,中国人每人每日重金属和有害元素经口摄入总量(膳食和中药材相加)分别为铅102·9μg;镉21·4μg;汞5·7μg;无机砷81·0μg。分别占各自的每天允许摄入量值为铅45·7%;镉34·0%;汞5·7%;砷60·5%。建议植物性中药材铅、镉、汞和砷限量标准为铅5·0mg/kg;镉0·3mg/kg;汞0·2mg/kg;砷2·0mg/kg。结论中药材铅、镉、汞和砷基线水平的调查是成功的,在此摄入水平,这些有害元素对人体是安全的。     

Exposure to arsenic and lead of children living near a copper-smelter in San Luis Potosi, Mexico: Importance of soil contamination for exposure of children

The objective of this study was to assess the levels of soil contamination and child exposure in areas next to a primary smelter (arsenic-copper metallurgical) located in the community of Morales in San Luis Potosi, Mexico. In Morales, 90% of the soil samples studied in this work were above 400 mg/kg of lead, and above 100 mg/kg of arsenic, which are guidelines recommended by the United States Environmental Protection Agency (EPA). Bioaccessibility of these metals was studied in vitro in 10 soil samples; the median values of bioaccessibility obtained in these samples were 46.5% and 32.5% for arsenic and lead. Since the concentrations of arsenic and lead in soil were above normal values, and taking into account the bioaccessibility results, exposure to these metals was evaluated in children. Regarding lead, children aged 3-6 years had the highest mean blood lead levels; furthermore, 90% of them had concentrations above 10 microg/dl (CDC's action level). Total urinary arsenic was higher in children aged 8-9 yr; however, the percentage of children with concentrations above 50 microg/g creatinine (CDC's action level) or 100 microg/g creatinine (World Health Organization [WHO] action level) was similar among different age groups. Using the EPAs integrated exposure uptake biokinetic model for lead in children (IEUBK), we estimated that 87% of the total lead in blood is obtained from the soil/dust pathway. The exposure dose to arsenic, estimated for the children living in Morales using Monte Carlo analysis and the arsenic concentrations found in soil, was above the EPA's reference dose. With all these results, it is evident that studies are needed in order to identify adverse health effects in children living in Morales; nevertheless, it is more important to develop a risk reduction program as soon as possible.     

Hair and toenail arsenic concentrations of residents living in areas with high environmental arsenic concentrations

Surface soil and groundwater in Australia have been found to contain high concentrations of arsenic. The relative importance of long-term human exposure to these sources has not been established. Several studies have investigated long-term exposure to environmental arsenic concentrations using hair and toenails as the measure of exposure. Few have compared the difference in these measures of environmental sources of exposure. In this study we aimed to investigate risk factors for elevated hair and toenail arsenic concentrations in populations exposed to a range of environmental arsenic concentrations in both drinking water and soil as well as in a control population with low arsenic concentrations in both drinking water and soil. In this study, we recruited 153 participants from areas with elevated arsenic concentrations in drinking water and residential soil, as well as a control population with no anticipated arsenic exposures. The median drinking water arsenic concentrations in the exposed population were 43.8 micro g/L (range, 16.0-73 micro g/L) and median soil arsenic concentrations were 92.0 mg/kg (range, 9.1-9,900 mg/kg). In the control group, the median drinking water arsenic concentration was below the limit of detection, and the median soil arsenic concentration was 3.3 mg/kg. Participants were categorized based on household drinking water and residential soil arsenic concentrations. The geometric mean hair arsenic concentrations were 5.52 mg/kg for the drinking water exposure group and 3.31 mg/kg for the soil exposure group. The geometric mean toenail arsenic concentrations were 21.7 mg/kg for the drinking water exposure group and 32.1 mg/kg for the high-soil exposure group. Toenail arsenic concentrations were more strongly correlated with both drinking water and soil arsenic concentrations; however, there is a strong likelihood of significant external contamination. Measures of residential exposure were better predictors of hair and toenail arsenic concentrations than were local environmental concentrations.     

On the content of arsenic, lead, copper, zinc, tin and iron in bottled fruit, strained fruit pulp and bottled jam produced in Poland

One hundred and fifty-three samples of bottled fruit, strained fruit pulps and jams contained in glass jars were analysed for heavy metals. All arsenic concentrations were less than the limit of detection of 0.04 mg/kg as were all tin concentrations for which the limit of detection was 8 mg/kg. The concentrations of the lead were all below 0.2 mg/kg for bottled fruit and 0.3 mg/kg for stained pulps and jams. In bottled fruit 98% of samples contained less than 3 mg/kg of copper, 98% less than 5 mg/kg of zinc and 97% less than 10 mg/kg of iron. In strained pulps all samples contained less than 2 mg/kg of copper and less than 5 mg/kg of zinc, 41% of samples contained less than 20 mg/kg of iron. In jams all samples contained less than 2 mg/kg of copper and less than 5 mg/kg of zinc, 96% samples contained less than 20 mg/kg of iron.     

Inorganic arsenic speciation in soil and groundwater near in-service chromated copper arsenate-treated wood poles

The environmental impact of chromated copper arsenate (CCA)-treated utility poles is linked to the possible soil and groundwater contamination with arsenic. The objective of the present study was to determine the arsenic speciation in soil and groundwater near in-service CCA-treated poles. Arsenite (As[III]) and arsenate (As[V]) concentrations were determined in 29 surface and subsurface soil samples collected near eight CCA-treated wood poles. Temporal variability of total arsenic concentrations and inorganic arsenic speciation was also assessed in groundwater at two sites through four sampling events over a 19-month period. Arsenic speciation was carried out by a solvent extraction method using ammonium pyrrolidine dithiocarbamate-methyl isobutyl ketone, and total arsenic was quantified by inductively coupled plasma/atomic emission spectrometry/hydride generation. Average arsenic concentrations in surface soils immediately adjacent to utility poles ranged from 153+/-49 to 410+/-150 mg/kg but approached background levels (below 5 mg/kg) within 0.50 m from the poles. A positive correlation was found between surface soil As concentration and total Fe content. In subsurface samples (0.50 m), arsenic levels were generally high in sandy soils (up to 223+/-32 mg/kg), moderate in clayey soils (up to 126+/-26 mg/kg), and relatively lower in organic soils (up to 56+/-24 mg/ kg). Arsenic(V) was the predominant arsenic species in surface (>78%) and subsurface soils (>66%). Total arsenic concentrations in groundwater below the clayey site were high and varied widely over time (79-390 microg/L), with 30 to 68% as As(III). Below the utility pole located on the organic site with a high Fe content, lower total arsenic levels (12-33 microg/L) were found, with As(III) ranging from 0 to 100%.     

亚砷酸钠单次染毒大鼠后唾液及血液总砷含量变化比较

目的比较亚砷酸钠单次染毒后大鼠血液及唾液中总砷含量随时间变化情况。方法健康清洁级SD大鼠21只,适应性饲养一周后一次性灌服亚砷酸钠20mg/kg。于给药前(0 h)和给药后1～2、4～5、7～8、11～12、17～18和23～24 h时间段分别收集血液和唾液,利用原子荧光分光光度计(AFS-230)检测血砷含量,电感耦合-等离子体质谱(ICP-MS)测定唾液砷含量。结果大鼠摄入亚砷酸钠后,其血液中砷含量急剧上升,在1～2小时便达到峰值,随后下降,但在第7～8小时又出现第二个峰值。唾液中砷含量上升趋势较血砷缓慢,在第7～8小时达到峰值,随后逐渐下降。唾液砷与血砷随时间变化趋势基本一致,且两者之间存在明显的正相关性,r=0.678(P<0.01)。结论砷在唾液中的代谢及排泄速率与血液相比较为缓慢,但总体趋势基本一致,表明唾液砷也能够反映机体砷暴露水平。