排序方式: 共有32条查询结果,搜索用时 0 毫秒
21.
某污水灌区居民胃癌高发的病因研究 总被引:2,自引:0,他引:2
某污水灌区居民恶性肿瘤死亡回顾调查发现,胃癌标化死亡率重污染地区明显高于一般污染区及对照区,是全国农村胃癌标化死亡率的3倍.通过污灌区居民临床体检和肠型胃癌的肠上皮抗原——α_2GP 对血清免疫学检测,发现胃癌高发与本地人群慢性萎缩性胃炎的粘膜肠上皮化生有密切联系,环境卫生与环境流行病学调查进一步证明污灌地区居民的胃粘膜肠上皮化生又和灌区污染的井水及稻米中某些矿物油、苯并(a)芘等污染物长期刺激有关,经试验均具有效突变活性.据此,作者初步提示了某污灌区居民胃癌的发生模型. 相似文献
22.
中国肝癌与土壤环境中化学元素的相关性研究 总被引:13,自引:1,他引:13
利用土壤元素资料2069448个数据,肝癌死亡调查资料121080例,研究了肝癌死亡率与土壤环境中64个元素的相关性。结果表明,64个元素中有18种元素的与肝癌死亡率有关,同时得到了相应的等级相关系数。 相似文献
23.
Erich Gebhart 《毒物与环境化学》2013,95(1-2):7-15
A very extensive and effective research in the fields of classical and molecular cytogenetics of cancer cells, during the past 10 years, has produced a rather concrete picture of the events and mechanisms rendering a normal cell a malignant one: Mutational changes in the control of so‐called cellular oncogenes play a fundamental role in cell transformation and tumor progression. These oncogenes are highly conservative and, therefore, important genes normally coding for a series of specific proteins particularly involved in growth control and differentiation processes. The most important alterations of these genes are: (1) Point mutations (e.g. base transitions) in essential base pairs of the respective proto‐oncogenes causing an uncontrolled expression of the latter, (2) translocations of specific chromosomal segments resulting in transfer of a proto‐oncogene from its normal (controlled) location into the area of highly active genes and by that in its activation, (3) amplification of DNA sequences including proto‐oncogenes which also can cause their over‐expression, (4) insertion of retroviral oncogenes into the DNA, (5) point mutations or deletions in “control genes” rendering the respective gene mutation homozygous or hemizygous. All these events are mutations in the strict sense the mutageneticist applies to the endpoints of his experimental studies. Above all, the fundamental importance of translocations and point mutations in the transformation process has clearly been evidenced by these data. Therefore, the design of experiments in mutagenicity testing should preferentially consider these types of mutations. Any mutagen, e.g. certain heavy metals or their compounds, inducing those types of mutations, must be considered suspicious not only concerning its mutagenicity in germ cells but also in somatic cells, and, by that, its carcinogenicity. 相似文献
24.
癌症与土壤环境中锆元素的关系 总被引:2,自引:0,他引:2
利用土壤环境中锆元素资料 767个数据和癌症死亡调查资料 7870 80例 ,研究了癌症死亡率与人群生存区土壤环境中锆元素的关系。结果表明 :肝癌、肺癌、鼻咽癌、乳腺癌死亡率与锆元素有相关性 ,等级相关系数分别为 0 5 0 44 (P <0 0 0 5 )、0 3 3 99(P <0 0 5 )、0 3 164 (P <0 0 5 )、0 3 197(P <0 0 5 )。 相似文献
25.
26.
Martí Nadal Marta Schuhmacher José L. Domingo 《Environmental science and pollution research international》2009,16(3):322-328
Background, aim, and scope To enforce the implementation of the Kyoto Protocol targets, a number of governmental/international institutions have launched
emission trade schemes as an approach to specify CO2 caps and to regulate the emission trade in recent years. These schemes have been basically applied for large industrial sectors,
including energy producers and energy-intensive users. Among them, cement plants are included among the big greenhouse gas
(GHG) emitters. The use of waste as secondary fuel in clinker kilns is currently an intensive practice worldwide. However,
people living in the vicinity of cement plants, where alternative fuels are being used, are frequently concerned about the
potential increase in health risks. In the present study, a cost–benefit analysis was applied after substituting classical
fuel for sewage sludge as an alternative fuel in a clinker kiln in Catalonia, Spain.
Materials and methods The economical benefits resulting in the reduction of CO2 emissions were compared with the changes in human health risks due to exposure to polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and carcinogenic metals (As, Cd, Co, and Cr) before and after using sewage sludge to
generate 20% of the thermal energy needed for pyro-processing. The exposure to PCDD/Fs and metals through air inhalation,
soil ingestion and dermal absorption was calculated according to the environmental levels in soil. The carcinogenic risks
were assessed, and the associated cost for the population was estimated by considering the DG Environment’s recommended value
for preventing a statistical fatality (VPF). In turn, the amount of CO2 emitted was calculated, and the economical saving, according to the market prices, was evaluated.
Results The use of sewage sludge as a substitute of conventional energy meant a probability cancer decrease of 4.60 for metals and
a cancer risk increase of 0.04 for PCDD/Fs. Overall, a net reduction of 4.56 cancers for one million people can be estimated.
The associated economical evaluation due to the decreasing cancer for 60,000 people, the current population living near the
cement plant, would be of 0.56 million euros (US$ 0.83 million). In turn, a reduction of 144,000 tons of CO2 emitted between 2003 and 2006 was estimated. Considering a cost of 20 euros per ton of CO2, the global saving would be 2.88 million euros (US$ 4.26 million).
Discussion After the partial substitution of the fuel, the current environmental exposure to metals and PCDD/Fs would even mean a potential
decrease of health risks for the individuals living in the vicinity of the cement plant. The total benefit of using sewage
sludge as an alternative fuel was calculated in 3.44 million euros (US$ 5.09 million). Environmental economics is becoming
an interesting research field to convert environmental benefits (i.e., reduction of health risks, emission of pollutants,
etc.) into economical value.
Conclusions The results show, that while the use of sewage sludge as secondary fuel is beneficial for the reduction in GHG emissions,
no additional health risks for the population derived from PCDD/F and metal emissions are estimated.
Recommendations and perspectives Cost–benefit analysis seems to be a suitable tool to estimate the environmental damage and benefit associated to industrial
processes. Therefore, this should become a generalized practice, mainly for those more impacting sectors such as power industries.
On the other hand, the extension of the study could vastly be enlarged by taking into account other potentially emitted GHGs,
such as CH4 and N2O, as well as other carcinogenic and non-carcinogenic micropollutants. 相似文献
27.
Mark K. Goldstein Salvador R. Bozzo Robert Malone Fernando Galdos Walter Sevian Donald Goellner 《Environmental management》1979,3(5):447-460
The data base for each process of the nuclear fuel cycle has been updated as a part of the Committee on Nuclear and Alternative Energy Systems (CONAES) at Brookhaven National Laboratory (BNL). The BNL Energy System Network Simulator (ESNS) was modified to accommodate the new data, and methodology was developed for estimating population dose and health effects resulting from atmosphere releases of radioactive materials from the nuclear fuel cycle.Estimates of population dose and health effects were made using these new CONAES emission data and the new model for three scenarios out to the year 2000: (1) no reprocessing; (2) reprocessing, 1-year cooling; and (3) reprocessing, 5-year cooling. Results indicate that radon emissions from mining and milling of uranium bearing ores will have greater impacts than any other component in the open nuclear fuel cycle. The estimated number of health effects will depend, to a large extent, on the lung model mechanism assumed to induce cancer; i.e., either the smeared or the unsmeared model. The smear model and the linear relationship predict for scenario 1, 630; for scenario 2, 949; and for scenario 3, 854 lung cancers, respectively, using the new CONAES data.Epidemiologic data from six United States counties were correlated using a new statistical model (described in the text) in order to test the validity of the lung model and the linear relationship. Results do not support the high lung cancer correlations expected from the unsmear model and the linear relationship; therefore, it is concluded that low-dose mechanisms may be different from those developed from high-dose data. The best place to look for effects of low-dose radiation may be the less developed countries because of a reduction in the noise level caused by chemical pollutants. 相似文献
28.
29.
This article highlights recent research on the beneficial use of selected low frequency electromagnetic fields (EMF) as a
safe alternative therapy for treatment of cancer and other health problems. It is shown that EMF therapy provides a safe alternative
and adjunct modality for the treatment of cancer and other health problems, and therefore, research in this field deserves
more support. The paper also discusses some reports and hypothesis of potential risk of human exposure to low frequency EMF,
mainly to the power line frequency of 60 Hz. 相似文献
30.
Wiktor Adamowicz Diane DupontAlan Krupnick Jing Zhang 《Journal of Environmental Economics and Management》2011,61(2):213-226
We examine the value of health risk reductions (microbial illnesses/deaths and bladder cancer illnesses/deaths) in the context of drinking water quality treatment by public systems. When we assume that combined mortality and morbidity risk reductions are equally spread in the future; our results suggest that microbial risk-reduction programs have higher value than cancer risk-reduction programs, but that mortality risk reduction values are not significantly different for cancer and microbials. However, when a 25-year cancer latency is accounted for and a 5% discount rate is used, the value of cancer mortality risk reductions exceeds the value for microbial risk reductions. We also address a number of methodological issues, including performance of alternative choice experiment estimation (CE) techniques, relationship of CE to contingent valuation results, and implications for incorporating morbidity and mortality endpoints in the same survey instrument. 相似文献