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为查明信宜-廉江地区地热水中氟的富集过程,于2018年4月采集地热水、河水和井水样品23组,采用Piper三线图、Gibbs图和同位素分析来探究高氟地热水的化学特征和分布规律,结合饱和指数、离子比例系数和相关性分析等方法揭示了高氟地热水的富集过程.结果显示,超过65%样品F~-含量大于1 mg·L~(-1),热水样品中超过83%的样品F~-含量大于1 mg·L~(-1),高氟水的水化学类型主要为HCO_3-Na型,高氟水表现出富钠、贫钙、弱碱性的特点;氢氧同位素数据表明地热水主要来源于大气降水,高氟水循环路径相对较长;水岩作用和含氟矿物的溶解是地热水中氟的主要来源,含钙矿物的溶解沉淀,吸附解吸作用和阳离子交换作用是地热水氟富集的主要影响因素. 相似文献
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燃煤污染型氟中毒病区人体氟通量的测定 总被引:1,自引:1,他引:1
燃煤污染型氟中毒病区氟的传输途径较为复杂 ,除燃煤烘烤的粮食和蔬菜外 ,还涉及到水、气及煤炭开采和运输中对外环境所形成的污染等 .但无论以什么渠道进入人体的过量氟 ,它所导致机体生化和病理改变的程度都与环境介质中的氟进入机体的通量有密切关系 .这里的环境介质系指与人体有关的尘土、饮水、空气、粮食、蔬菜等 .近年来 ,我国在燃煤污染型氟中毒的环境流行因素调查和防治科研等方面进行了大量的工作 ,并取得一系列成果 .本文就典型病区生态系统中氟的传输通量予以初步探讨 ,以期为燃煤污染型氟中毒病区环境氟的风险评价和防治重心的… 相似文献
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新疆喀什地区地下水氟的空间分布规律及其富集因素分析 总被引:1,自引:0,他引:1
高氟地下水严重影响当地居民的身体健康.基于新疆喀什地区571个地下水样的氟离子实测含量,运用Mapgis软件绘制研究区地下水氟含量分布图,结果表明,研究区地下水氟含量呈西部、北部高于东部、南部,中部最低的特点;山麓斜坡冲洪积砾质平原区氟含量表现为浅层潜水高于深层潜水,中下游河流冲积平原区地下水氟含量表现为潜水浅层承压水深层承压水.采用绘制Gibbs图、Piper三线图、离子比例图等方法对研究区水化学环境特征及地下水氟的富集因素进行研究,结果表明,研究区地下水氟源于山前含氟基岩;受地下水径流条件影响,研究区地下水氟含量平均值表现为中下游河流冲积平原区山麓斜坡冲洪积砾质平原区;蒸发浓缩作用使F~-浓度进一步增大;研究区高氟地下水水化学类型主要为HCO_3-Na和Cl·SO_4-Na型,地下水弱碱性环境有助于F~-的富集. 相似文献
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地下水氟污染及其迁移转化模拟试验的初步分析 总被引:2,自引:1,他引:2
本文分析了地下水含氟量的变化特征以及氟污染地下水的类型、并通过不同pH值、不同含钙、氟浓度的溶液和工业废水淋溶各种土壤的试验,以初步研究氟在土壤、地下水中迁移、转化的规律。又阐述了我国地方性氟中毒主要分布地带的特征。最后提出了防止氟中毒和地下水氟污染的措施。 相似文献
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燃煤电厂氟污染与治理对策 总被引:4,自引:0,他引:4
本文以一个包含干湿两种除尘系统的高氟煤源的电厂为例,研究了电厂的氟迁移转化规律和氟污染源对周围环境的影响。并提出了综合治理电厂氟污染的对策。研究表明:湿法除尘系统的氟污染物主要是渣氟、水氟,而干法除尘系统主要是渣氟和气氟;小麦氟含量与大气中氟显著相关;灰场附近的地表水受到灰水的氟污染,部分潜水井受到了灰场渗水的污染,部分灰场土壤受到大气氟污染。 相似文献
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针对苏南某农业区浅层地下水中DDTs的污染特征进行了初步分析,结果表明,浅层地下水中DDTs最大检出质量浓度为1.04 μg·L-1,最大检出率为36.67%.浅层地下水DDTs污染呈散状分布,浓度高值点集中在研究区东北部,污染范围大,且表现出丰水期、平水期和枯水期含量依次递减的季节性变化特征.该地区包气带防污性能良好,黏土矿物和有机碳对DDTs吸附作用较强,可阻滞其向浅层地下水环境中迁移,是造成部分地段浅层地下水未检出DDTs污染的重要原因.受污染地表水体的垂向入渗是导致浅层地下水DDTs污染的直接原因,其侧向补给可能是浅层地下水DDTs污染的重要来源之一,且污染范围往往局限于地表水体附近地带. 相似文献
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安徽省长江以北地区土壤水溶性氟含量及分布特征 总被引:2,自引:0,他引:2
郑路 《生态与农村环境学报》1997,(3)
采集安徽省长江以北地区有代表性土壤样品347个,测定了其水溶性氟含量。结果表明,土壤水溶性氟含量范围038~1269mg/kg,平均为238mg/kg。地区分布是南低北高,以淮北宿州和阜阳地区为最高,平均含量在3mg/kg以上。主要土壤类型土壤水溶性氟含量顺序是砂姜黑土、潮土>黄棕壤、紫色土>水稻土>石灰土、粗骨土。不同母质土壤水溶性氟含量顺序是古黄土性河湖相沉积物>黄泛冲积物>紫色砂岩>下蜀黄土>石灰岩>酸性结晶岩风化物>河流冲积物。土壤水溶性氟含量与土壤pH呈正相关。pH高的黄泛冲积物和古黄土性河湖相沉积物母质土壤含水溶性氟多,该土壤地区发生氟中毒可能性较大。 相似文献
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Fluoride contamination in groundwater of central Rajasthan,India and its toxicity in rural habitants
This study was carried out to assess fluoride (Fl) concentration in groundwater in some villages of central Rajasthan, India, where groundwater is the main source of drinking water. Water samples collected from deep aquifer-based hand pumps were analyzed for Fl content. Fluoride in groundwater of 121 habitations of Bhilwara tehsil of Bhilwara district of Rajasthan was determined to examine the potential Fl-induced toxicity in rural locations. Fluoride concentrations in the tehsil ranged from 0.5 to 5.8 mg/l. In the tehsil, 69 villages (57%) were found to have Fl concentration beyond the maximum desirable limit recommended in Bureau of Indian Standards (BIS), 10500, 1991. Fifty-eight percent population of these villages was under the threat of fluorosis. One percent population of tehsil living in two villages ingested more than 5 mg/l Fl in each liter of drinking water and at maximal risk for dental and skeletal fluorosis. 142 individuals of these villages were examined for fluorosis. Data indicated that only four individuals (2.82%) did not exhibit dental fluorosis. Most individuals were found to suffer from mild (34.51% or 49 individuals) and moderate (31.69% or 45 individuals) fluorosis. Severe dental fluorosis was recorded in only 16 individuals (11.27%). In 104 individuals above 21 years of age examined for the prevalence of skeletal fluorosis, 66 were positive for skeletal fluorosis with a maximum 36.5% with grade I skeletal fluorosis. Grade II skeletal fluorosis was recorded in 28 individuals (26.9%). Data in this study demonstrate that there is a need to take ameliorative steps in this region to prevent fluorosis. 相似文献
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Maiti SK Das PK Ray SK 《Journal of environmental biology / Academy of Environmental Biology, India》2003,24(4):465-470
Chronic fluoride toxicity in the form of dental fluorosis was observed in cattle from nine (9) villages under two (2) blocks of Nayagarh district of Orissa. Out of 1117 cattle, 221 (18.09%) showed the signs of dental fluorosis. In all affected villages, the prevalence of dental fluorosis in calves (< 1 year age) was greater than adults. There was significant difference in prevalence in respect to age. The commonly observed signs of dental fluorosis were brown discoloration, mottling, attrition or uneven wearing of teeth with or without pitting. None of the affected animals showed characteristic signs of osteofluorosis. The mean serum and urine fluoride concentration of affected animals were significantly (P < 0.05) higher than those of control animals. Fluoride levels (mean) of ground water and surface water in two blocks were 1.30 +/- 0.16 ppm, 0. 66 +/- 0.08 ppm and 1.12 +/- 0.19 ppm, 0. 48 +/- 0.05 ppm respectively. The fluoride content of grass samples of affected and control (non-endemic) area was comparable. There was a highly positive correlation (r = + 0.664) between prevalence of dental fluorosis and fluoride content of ground water. It was concluded that fluoride intake through the water especially ground water contributed to the development of fluorosis in cattle. 相似文献
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Distribution and Risk Assessment of Fluoride in Drinking Water in the West Plain Region of Jilin Province, China 总被引:3,自引:0,他引:3
Bo Z Mei H Yongsheng Z Xueyu L Xuelin Z Jun D 《Environmental geochemistry and health》2003,25(4):421-431
The west plain region of Jilin province of northeast China is one of the typical endemic fluorosis areas caused by drinking water for many years. Investigations of hydrogeological and ecoenvironmental conditions as well as endemic fluorosis were conducted in 1998. Results show that the ground water, especially, the water in the unconfined aquifer is the main source of drinking water for local residents. The fluoride concentration in groundwater in the unconfined aquifers is higher than that in the confined aquifer in the west plain of Jilin province. The fluoride concentration in the unconfined aquifer can be used to classify the plain into fluoride deficient area, optimum area and excess area, which trend from west to east. High fluoride (>1.0 mg L(-1)) in drinking water resulted in dental and skeletal fluorosis in local residents (children and pregnant women). There exists a positive correlation between fluoride concentration in the drinking water and the morbidities of endemic fluorosis disease (r1 = 0.781, r2 = 0.872). Health risks associated with fluoride concentration in drinking water are assessed. It has been determined that fluoride concentration in excess of 1.0 mg L(-1) exposes residents to high health risks based on risk identification. The study area is classified into five health risk classes as shown in Figure 4. The risk indexes of this area more than 1.0 are accounted for 68% of the total west plain region. 相似文献
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Zheng B Wu D Wang B Liu X Wang M Wang A Xiao G Liu P Finkelman RB 《Environmental geochemistry and health》2007,29(2):103-108
In this study, investigations into endemic fluorosis were conducted and fluorine concentration in environmental samples determined.
In an indoor coal-combustion-type fluorosis area, local clay was used to mix with coal for indoor combustion. There are two
key steps in the procedure of the indoor transition of fluorine: indoor wet corns and vegetables strongly absorbed fluorine
from indoor air; and fluorine strongly accumulated in clay, which was mixed with coal for combustion. Therefore, with the
increasing of the percentage of clay in the clay-mixed coal as well as corn in foodstuff, the ratio of fluorosis will be increased. 相似文献
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饮水的化学组分与地氟病的关系 总被引:2,自引:0,他引:2
饮水的化学成分分析结果表明,徐州地区居民饮用水中的氟含量pH,Na^+,HCO^-3,As,B和矿化度呈正相关关系,与K^+,Ca^2+,Al^3+,Ba^2+,Si^4+呈负相关关系。地氟病的发病率不仅与饮水的氟含量密切相关,而且受饮水中其它组份的制榴,饮水中Ca^2+,Al^3+,Sr^2+,B,Si^4+,K^+,Ge^4+等组分的增高可抑制或减缓地氟病的发生。 相似文献
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Implications of fluoride--an endless uncertainty 总被引:1,自引:0,他引:1
Pillai KS Stanley VA 《Journal of environmental biology / Academy of Environmental Biology, India》2002,23(1):81-87
Fluorosis has become pandemic and it has assumed global status in the public health point of view. The paper deals with the health issues pertaining to fluorosis with special emphasis in the Indian context. It explains the equivocal evidences of fluoride-related problems and discusses the control measures of fluorosis. In general, it reveals how fluoride is useful at very low concentrations and at the same time brings forth manifestation of clinical abnormalities at higher concentrations that are the basis of the principles of toxicology. 相似文献
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Rachel Allibone Shane J. Cronin Douglas T. Charley Vince E. Neall Robert B. Stewart Clive Oppenheimer 《Environmental geochemistry and health》2012,34(2):155-170
Ambrym in Vanuatu is a persistently degassing island volcano whose inhabitants harvest rainwater for their potable water needs.
The findings from this study indicate that dental fluorosis is prevalent in the population due to fluoride contamination of
rainwater by the volcanic plume. A dental survey was undertaken of 835 children aged 6–18 years using the Dean’s Index of
Fluorosis. Prevalence of dental fluorosis was found to be 96% in the target area of West Ambrym, 71% in North Ambrym, and
61% in Southeast Ambrym. This spatial distribution appears to reflect the prevailing winds and rainfall patterns on the island.
Severe cases were predominantly in West Ambrym, the most arid part of the island, and the most commonly affected by the volcanic
plume. Over 50 km downwind, on a portion of Malakula Island, the dental fluorosis prevalence was 85%, with 36% prevalence
on Tongoa Island, an area rarely affected by volcanic emissions. Drinking water samples from West Ambrym contained fluoride
levels from 0.7 to 9.5 ppm F (average 4.2 ppm F, n = 158) with 99% exceeding the recommended concentration of 1.0 ppm F. The pathway of fluoride-enriched rainwater impacting
upon human health as identified in this study has not previously been recognised in the aetiology of fluorosis. This is an
important consideration for populations in the vicinity of degassing volcanoes, particularly where rainwater comprises the
primary potable water supply for humans or animals. 相似文献
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Fluoride (F) distribution and its effects (fluorosis) were investigated in Antarctica. Droppings (L) excreta selected of aquatic birds, lake water, soil and moss (Polytrichum alpinum) showed a high F concentration. Although bones of Adelie penguin (Pygiscelis adeliae) and skua (Catharacta maccormicki) showed exceptionally very high F concentration in the range of 832 to 7187 mg kg(-1), their radiographs did not show any evidence of skeletal fluorosis. The possible reason and geochemical aspects of F in Antarctica region are discussed. 相似文献
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The Contribution of Drinking Water towards Dental Fluorosis: A case study of Njoro Division, Nakuru District, Kenya 总被引:1,自引:0,他引:1
Wilkister K. Moturi Mwakio P. Tole Theo C. Davies 《Environmental geochemistry and health》2002,24(2):123-130
This study was carried out to measure the fluoride levels of water consumed in the Njoro division of Nakuru district, Kenya. The sources of drinking water, methods of water storage and utilisation, as well as the perceptions of the local community towards dental fluorosis and the percentage of children with moderate to severe dental fluorosis were also determined. Rainwater had mean fluoride levels of 0.5 mg L-1, dams 2.4 mg L-1, wells 4.1 mg L-1, springs 5.5 mg L-1, and boreholes 6.6 mg L-1. Water stored in plastic and cement containers did not show appreciable reduction in fluoride content with storage time; water stored in metal containers reduced fluoride by up to 8.2%; water stored in clay pots had the highest reduction in fluoride content, ranging between 34.3 and 64.7%;. Forty eight point three percent of children observed in the area had moderate to severe dental fluorosis, even though most people in the area did not know the cause of the problem.There is need to educate the community on the causes of fluorosis, and to lay strategies for addressing the issue, such as encouraging more rainwater harvesting, treating drinking water with alum, or using clay pots for storage of drinking water. 相似文献