被認(rèn)為造成了地球最大的大滅絕——它在2.5億年前殺死了70%以上的植物和動(dòng)物——的火山爆發(fā)在今天仍然正在奪走生命,。這是一項(xiàng)新的研究得出的結(jié)論,，該研究首次證明了中國一個(gè)地區(qū)的煤的豐富的硅石成分可能與煤的揮發(fā)性物質(zhì)相互作用,，從而導(dǎo)致高得不尋常的肺癌發(fā)病率,。這項(xiàng)研究有助于解決這種癌癥之謎,，它發(fā)表在了ACS的半月刊《環(huán)境科學(xué)與技術(shù)》上,。
David Large及其同事指出,，中國云南省宣威縣的一些地區(qū)的不吸煙女性有全世界最高的肺癌發(fā)病率——是中國其他地方的20倍,。該地區(qū)的女性用敞開的燃煤爐為家庭取暖和做飯,，這些爐子并不把煙排往室外?？茖W(xué)家認(rèn)為來自燃燒的煤的室內(nèi)排放導(dǎo)致了癌癥,，但是還不清楚為什么該地區(qū)的癌癥發(fā)病率比其它地區(qū)高這么多。此前的研究表明了在煤煙中的稱為PAHs的某些揮發(fā)性物質(zhì)與該地區(qū)的肺癌之間的聯(lián)系,。
這組科學(xué)家發(fā)現(xiàn)在宣威縣的一些地區(qū)使用的煤的硅石（一種可疑致癌物）含量是美國的煤的10倍以上,。他們指出，硅石可能與PAHs聯(lián)合起來讓煤變得更致癌,。這組科學(xué)家還發(fā)現(xiàn)了這種高硅石含量的煤形成于2.5億年前,，當(dāng)時(shí)大規(guī)模的火山噴發(fā)讓硅石沉積在了形成宣威煤的泥炭中。（生物谷Bioon.com）
生物谷推薦原始出處：
Environ. Sci. Technol., 2009, 43 (23), pp 9016–9021 DOI: 10.1021/es902033j
Silica-Volatile Interaction and the Geological Cause of the Xuan Wei Lung Cancer Epidemic
David J. Large*?, Shona Kelly?, Baruch Spiro§, Linwei Tian, Longyi Shao?, Robert Finkelman#, Mingquan Zhang, Chris Somerfield?, Steve Plint?, Yasmin Ali? and Yiping Zhou
Department of Chemical and Environmental Engineering, University of Nottingham, Nottingham, NG7 2RD, U.K., Division of Epidemiology and Public Health, University of Nottingham, Nottingham, NG7 2RD, U.K., Department of Mineralogy, Natural History Museum, Cromwell Road London, SW7 5DB, U.K., School of Public Health, Chinese University of Hong Kong, Hong Kong SAR, China, State Key Laboratory of Coal Resources and Safe Mining, China University of Mining and Technology, Beijing 100083, China, The University of Texas at Dallas, F021, Richardson, Texas 75080-3021, and Yunnan Institute of Coal Geology Prospection, Kunming, 650218, China
Parts of Xuan Wei County, Yunnan Province, China have the highest known lung cancer mortality in nonsmoking women. This high mortality displays a clear spatial relationship to the mines producing coal from the uppermost Permian. Geochemical, petrographic, and grainsize analyses were undertaken on a set of coal samples from Xuan Wei. Results demonstrate that the single geochemical property that makes this coal unusual is its high concentration of quartz (13.5 wt %) of which 35?55% occurs as <10 μm grains. We propose the potential for silica?volatile interaction (PSVI) as a new method for assessing the combined influence of silica and volatile organic matter and use this as a basis for re-evaluating existing ecological data. Published lung cancer mortality values are more strongly correlated with PSVI values for Xuan Wei coal than with volatiles or silica alone and the PSVI values measured are distinct from those of other coals. Finally we propose that the localization of this epidemic to Xuan Wei results from enhanced weathering of the local Emeishan basalts as a consequence of geochemical perturbations at the Permo-Triassic Boundary.
