环境地球化学与人体健康的关系

本文探讨了环境地球化学与人体健康的关系,试图以医学与环境地球化学相结合和元素地球化学分布与生态学特征相结合的方式进一步阐述这一问题,揭示其内在联系和规律。最后从营养角度讨论了强身健体、延年益寿的方法。     

基于毒性效应的非目标化学品鉴别技术进展

现代社会大量化学品的生产与广泛使用造成了地表水、地下水、沉积物、土壤等环境受到污染,并对人体健康和生态系统构成威胁。基于毒性效应的关键致毒物质鉴别技术(effect directed analysis,EDA)已经在水体、沉积物的致毒物筛选方面得到了一定的应用。但是由于污染物组成复杂、范围广、基质干扰高、同分异构体广泛存在、人工合成标样缺少等问题,非目标致毒化合物的鉴别成为了EDA的瓶颈技术。逐渐发展的色谱与质谱技术、数据库指标在化合物筛选识别中发挥了重要作用。本文综述了基于高分辨质谱,数据库搜索,色谱保留特征,模型构建来筛选识别化合物的方法,总结了近年来化合物筛选识别方法在环境新型污染物及药物筛选等方面的应用并分析了化合物筛选识别所存在的问题与应用前景。这些方法可以提高非目标化合物筛选的准确性和通量,减少样品复杂性和基质干扰带来的负面影响,从而有利于未知化合物的确定。     

Trace metal concentrations in hairs of three bat species from an urbanized area in Germany

Metal-contaminated soils and sediments are widespread in urbanized areas due to atmospheric deposition close to emission sources. These metals are bio-available for organisms, e.g., insects, and accumulate in food chains of insectivorous mammals. Especially bats, which live in urban regions and ingest large amounts of food relative to their body mass, are at risk of being poisoned due to the accumulation of trace metals. To determine species-specific trace metal contents in bats from urban environments, hair samples were analyzed by ICP-OES. Observed trace metal concentrations were related to species-specific foraging habitat, prey spectrum and degree of synanthropy. The species studied were Pipistrellus pipistrellus, Myotis daubentonii and Nyctalus noctula. P. pipistrellus showed the highest concentrations of lead and zinc and slightly higher concentrations of cadmium than the other two species, which was related to its high degree of synanthropy with foraging habitat mostly located in cities. In contrast, N. noctula displayed the highest contents of manganese and copper. The reason might be found in its prey spectrum, as N. noctula feeds mainly on beetles that are caught in cultured areas. Trace metal concentrations determined in hair samples of M. daubentonii ranged between the values of P. pipistrellus and N. noctula, probably reflecting an intermediate level of synanthropy. Positive correlations were observed between the concentrations of cadmium and lead and those of manganese and copper. Hair samples from bats are suitable monitoring tools to study trace metal exposure and can be used to determine differences in trace metal levels between species.     

母乳与牛乳中微量元素的比较

用ＩＣＰ－ＡＥＳ法对母乳和牛乳中Ｋ、Ｎａ、Ｃａ、Ｍｇ、Ｐ、Ｆｅ、Ａｌ、Ｚｎ、Ｓｒ、、Ｐｂ、Ｍｎ、Ｂａ和Ｃｕ等１３种元素含量进行了测定。结果发现母乳与牛乳的营养成分差异较大。研究了深入探讨微量元素在人体内重要的生理功能提供了有用的参考数据。     

Geochemistry of the barkinite liptobiolith (Late Permian) from the Jinshan Mine,Anhui Province,China

This paper discusses the geochemistry and mineralogy of the barkinite liptobiolith of the Late Permian age from the Jinshan Mine, Guangde County, Anhui Province, China. Samples were examined using inductively coupled plasma-mass spectroscopy, X-ray fluorescence, cold-vapor atomic absorption spectrometry, ion-selective electrode, sequential chemical extraction, scanning electron microscopy equipped with energy-dispersive X-ray, and optical microscopy. The coal is a medium-ash and high-sulfur resource. Minerals in the coal are composed of kaolinite, pyrite, calcite, and quartz. Pyrite and calcite are derived from seawater during peat accumulation. Quartz in the coal is of authigenic origin. Part of the kaolinite is from a land-source region, and part occurs as cell-fillings and is of authigenic origin. The results also indicate that the barkinite liptobiolith contains some toxic elements in high concentrations. Elements including Li, Be, Si, Sc, Ti, V, Cr, Fe, Ga, Se, Y, Zr, Mo, the rare earth elements (REEs), W, Hg, Tl, Pb, Th, and U in the coals are enriched in the barkinite liptobiolith. Results of sequential chemical extraction showed that Li, Sc, Ti, Cr, Y, Zr, REEs, and Th in the coal mainly occur as silicates, while Be and W are related to organic matter. Pyrite is the dominant source of S, Mo, Hg, Tl, and Pb. Gallium only occurs in silicate, and U and V occur both in organic and silicate associations.     

Monitoring and assessment of toxic metals in Gulf War oil spill contaminated soil using laser-induced breakdown spectroscopy

Laser-induced breakdown spectroscopy (LIBS) was applied for the detection of toxic metals in oil spill contaminated soil (OSCS). The OSCS samples were collected from Khursania Saudi Arabia along the coast of Persian Gulf exposed to oil spills in 1991 Gulf war. Environmentally important elements like Aluminum Magnesium, Calcium, Chromium, Titanium, Strontium, Iron, Barium, Sodium, potassium, Zirconium and Vanadium from the contaminated soil have been detected. Optimal experimental conditions for analysis were investigated. The LIBS system was calibrated using standard samples containing these trace elements. The results obtained using Laser-Induced Breakdown Spectroscopy (LIBS) were compared with the results obtained using Inductively Coupled Plasma Emission Spectroscopy (ICP). The concentrations of some elements (Ba and Cr) were found higher than permissible safe limits. Health risks associated with exposure to such toxic elements are also discussed.     

Trace metal levels and some chemical parameters in herby cheese collected from south eastern Anatolia-Turkey

Due to the consumption of the herby cheese in south eastern Anatolia-Turkey is at high ratio, chemical parameters such as dry matter, pH, acidity, aCl, protein, fat and trace metal contents in 50 different herby cheeses produced at this region have been determined in the presented study. The content of lead, copper, cobalt, nickel, chromium, cadmium, and iron have been analyzed by flame atomic absorption spectrometer in air/acetylene flame after combination ash digestion method and wet digestion method. The mean concentration of lead, copper, cobalt, nickel, chromium and cadmium in our samples are higher than literature values except iron.     

Effects of different Ca2+ behavior patterns in the electric field on membrane fouling formation and removal of trace organic compounds

The effects of Ca²⁺on membrane fouling and trace organic compounds(TrOCs) removal in an electric field-assisted microfiltration system were investigated in the presence of Na+alone for comparison. In the electric field, negatively charged bovine serum albumin(BSA)migrated towards the anode far away from the membrane surface, resulting in a 42.9% transmembrane pressure(TMP) reduction in the presence of Na+at 1.5 V. In contrast, because of the stronger charge shielding of Ca²⁺     

Natural radioactivity and trace metals in crude oils: implication for health

Crude oil samples were collected from six different fields in the central Niger Delta in order to determine their natural radioactivity and trace element contents, with the aim of assessing the radiological health implications and environmental health hazard of the metals, and also to provide natural radioactivity baseline data that could be used for more comprehensive future study in this respect. The activity concentrations of the radionuclides were measured using a well, accurately calibrated and shielded vertical cryostat, Canberra coaxial high-purity germanium (HPGe) detector system, and the derived doses were evaluated. The metal concentrations were determined by the graphite furnace atomic absorption spectroscopic (GFAAS) method. The radionuclides identified with reliable regularity belong to the decay series of naturally occurring radionuclides headed by ²³⁸U and ²³²Th along with the non-decay series radionuclide, ⁴⁰K. The averaged activity concentrations obtained were 10.52 ± 0.03 Bq kg⁻¹, 0.80 ± 0.37 Bq kg⁻¹ and 0.17 ± 0.09 Bq kg⁻¹ for ⁴⁰K, ²³⁸U and ²³²Th, respectively. The equivalent doses were very low, ranging from 0.0028 to 0.012 mSv year⁻¹ with a mean value of 0.0070 mSv year⁻¹. The results obtained were low, and hence, the radioactivity content from the crude oils in the Niger delta oil province of Nigeria do not constitute any health hazard to occupationally exposed workers, the public and the end user. The concentrations of the elements (As, Cd, Co, Fe, Mn, Ni, Se and V) determined ranged from 0.73 to 202.90 ppb with an average of 74.35 ppb for the oil samples analysed. The pattern of occurrence of each element agreed with the earlier studies from other parts of the Niger Delta. It was obvious from this study and previous ones that the Niger Delta oils have low metal contents. However, despite the low concentrations, they could still pose an intrinsic health hazard considering their cumulative effects in the environment. Also, various studies on the impact of oil spillage and activities of oil exploration and production on organisms in the immediate environment suggest this.     

Chemical indicators of anthropogenic impacts in sediments of the pristine karst lakes

The anthropogenic impact on the pristine karst lakes was investigated using combination of specific parameters, including multielemental analysis of major inorganic constituents (Al, K, Fe) and trace metals (Li, Ag, Cd, Sn, Pb, Bi, Cr, Co, Ni, Cu, Zn and Sb), polycyclic aromatic hydrocarbons (PAHs) and anionic surfactants of linear alkylbenzene sulfonate (LAS) type. The study was performed in the Plitvice Lakes National Park, situated in a sparsely populated area of the northwestern Dinarides, central Croatia. Dated cores of recent sediments from the two biggest lakes, Lake Prosce and Lake Kozjak, were analysed for the selected contaminants using highly specific methods, involving inductively coupled plasma mass spectrometry (ICP/MS), gas chromatography/mass spectrometry (GC/MS) and liquid chromatography/tandem mass spectrometry (LC/MS/MS). The concentration of inorganic constituents reflected primarily the geological background of the area as well as geomorphological and geochemical characteristics of the Plitvice Lakes. Due to the higher terrigenous input, the concentration of all elements was significantly higher in the Lake Prosce. The concentration of toxic metals was relatively low in both lakes, except for Cd (>1 mg kg⁻¹) and Pb (up to 40 mg kg⁻¹). The vertical profiles of these metals suggested that elevated concentrations of Cd were of natural origin, derived from the erosion of the Jurassic dolomite bedrock, while Pb was predominately of recent anthropogenic origin. A similar distribution pattern, suggesting the same prevailing mechanism of input, was observed for pyrolytic PAHs. The characteristic diagnostic PAH ratios revealed that higher PAHs prevailingly originated from the combustion of biomass and fossil fuels. LAS, which represent highly specific indicators of untreated wastewaters, were found in rather high concentrations in the recent sediment layers (up to 4.7 mg kg⁻¹), suggesting that contaminated household and hotel wastewaters reach the Lakes, very probably by leaking through the porous karst rocks.