氡被稱(chēng)為“導(dǎo)致人類(lèi)肺癌的第二大‘殺手’

2006/9/9 10:05:00

氡從何處來(lái)堅實基礎？
    室內(nèi)氡的來(lái)源是多途徑的，但主要是：
    １重要作用、巖石（土壤）是室內(nèi)氡積累的普遍而直接的來(lái)源等地，而且是主要的來(lái)源（當(dāng)居室中各類(lèi)建材的放射性符合國(guó)家標(biāo)準(zhǔn)時(shí)）。
    ２尤為突出、構(gòu)造帶規定。構(gòu)造帶不是直接的氡來(lái)源，但它是地下氡匯集和遷移的通道空間載體，有時(shí)比巖石因素更重要高質量。例如某地房屋建在裂隙不很發(fā)育的花崗巖上相對簡便，在相同的其他建材條件下，室內(nèi)的氡往往要比房屋建在放射性較低流程，而裂隙發(fā)育又相當(dāng)厲害的砂巖上為低合作。
    ３、水源有時(shí)也是室內(nèi)氡的重要來(lái)源深刻變革，直接來(lái)自地下的結論、鈾礦區(qū)或油氣田區(qū)的水往往有較高的氡濃度。
    ４質生產力、在房屋基底經(jīng)完好密封時(shí)適應性強，墻地磚的放射性就成了室內(nèi)氡的主要來(lái)源。
    ５處理、煤氣通常稱(chēng)液化氣或天然氣建設，往往有著相對(duì)高的氡濃度。

    氡對(duì)人體的主要傷害是什么助力各行？
    專(zhuān)家們把氡稱(chēng)為“導(dǎo)致人類(lèi)肺癌的第二大‘殺手’”，是除吸煙以外引起肺癌的第二大因素自主研發。世界衛(wèi)生組織把氡列為使人致癌的19種物質(zhì)之一確定性。

    如何降低居室中的氡？
    １損耗、不要購(gòu)買(mǎi)建筑在富鈾區(qū)講故事、伽瑪高值區(qū)、斷裂構(gòu)造區(qū)的樓宇性能穩定。要知道室內(nèi)的氡含量是否超標(biāo)全面革新，最有效的方法就是進(jìn)行室內(nèi)氡濃底的檢測(cè)，個(gè)人購(gòu)買(mǎi)住房時(shí)情況正常，也應(yīng)考慮這個(gè)因素行業分類。
    ２、在裝飾裝修時(shí)提高鍛煉，要盡量按照國(guó)家標(biāo)準(zhǔn)選用放射性含量低的建筑和裝飾材料發展邏輯。
    ３、室內(nèi)裝飾中有所提升，要注意填平聽得進、密封地板和墻上的所有裂縫，特別是地下室先進水平、一層和平房的住戶(hù)更要如此便利性。
    ４、做好室內(nèi)通風(fēng)換氣重要平臺，這是最簡(jiǎn)便深刻認識、最省錢(qián)的方法學習。門(mén)窗關(guān)閉的房屋內(nèi)，氡的濃度往往比敞開(kāi)門(mén)窗時(shí)高數(shù)倍到數(shù)十倍聽得懂。專(zhuān)家曾做過(guò)試驗(yàn)應用優勢，一間氡濃度在151貝可/m3　房間，開(kāi)窗１小時(shí)后全方位，室內(nèi)氡濃度可降為48貝可/m3高效節能。如果配備優(yōu)質(zhì)的室內(nèi)空氣凈化器更好。
    ５大局、孩子與婦女比成年男性更易受氡侵害新創新即將到來，應(yīng)盡量減少或禁止在室內(nèi)吸煙。

國(guó)外相關(guān)報(bào)道：

美國(guó)環(huán)保署：http://www.epa.gov/radon/healthrisks.html

Exposure to Radon Causes Lung Cancer In Non-smokers and Smokers Alike

Lung cancer kills thousands of Americans every year. The untimely deaths of Peter Jennings and Dana Reeve have raised public awareness about lung cancer, especially among people who have never smoked. Smoking, radon, and secondhand smoke are the leading causes of lung cancer.  Although lung cancer can be treated, the survival rate is one of the lowest for those with cancer.  From the time of diagnosis, between 11 and 15 percent of those afflicted will live beyond five years, depending upon demographic factors.  In many cases lung cancer can be prevented; this is especially true for radon.

Smoking is the leading cause of lung cancer.  Smoking causes an estimated 160,000* deaths in the U.S. every year (American Cancer Society, 2004).  And the rate among women is rising.  On January 11, 1964, Dr. Luther L. Terry, then U.S. Surgeon General, issued the first warning on the link between smoking and lung cancer.  Lung cancer now surpasses breast cancer as the number one cause of death among women.  A smoker who is also exposed to radon has a much higher risk of lung cancer.

Radon is the number one cause of lung cancer among non-smokers, according to EPA estimates.  Overall, radon is the second leading cause of lung cancer.  Radon is responsible for about 21,000 lung cancer deaths every year.  About 2,900 of these deaths occur among people who have never smoked.  On January 13, 2005, Dr. Richard H. Carmona, the U.S. Surgeon General, issued a national health advisory on radon.  Visit www.cheec.uiowa.edu/misc/radon.html⁷  for more on a study by Dr. William Field on radon-related lung cancer in women.

Secondhand smoke is the third leading cause of lung cancer and responsible for an estimated 3,000 lung cancer deaths every year.  About 1,000 of these are people that never smoked, and about 2,000 are former smokers.  Smoking affects non-smokers by exposing them to secondhand smoke.  Exposure to secondhand smoke can have serious consequences for children’s health, including asthma attacks, affecting the respiratory tract (bronchitis, pneumonia), and may cause ear infections.

Learning more about lung cancer.  The following sources provide a wide range of good information about lung cancer, prevention, and treatment.

Why is radon the public health risk that it is? 

EPA estimates that about 20,000 lung cancer deaths each year in the U.S. are radon-related.  Exposure to radon is the second leading cause of lung cancer after smoking.  Radon is an odorless, tasteless and invisible gas produced by the decay of naturally occurring uranium in soil and water.  Radon is a form of ionizing radiation and a proven carcinogen.  Lung cancer is the only known effect on human health from exposure to radon in air.  Thus far, there is no evidence that children are at greater risk of lung cancer than are adults.

Radon in air is ubiquitous. Radon is found in outdoor air and in the indoor air of buildings of all kinds.  EPA recommends homes be fixed if the radon level is 4 pCi/L (pico Curies per Liter) or more. Because there is no known safe level of exposure to radon, EPA also recommends that Americans consider fixing their home for radon levels between 2 pCi/L and 4 pCi/L. The average radon concentration in the indoor air of America’s homes is about 1.3 pCi/L. It is upon this level that EPA based its estimate of 20,000 radon-related lung cancers a year upon. It is for this simple reason that EPA recommends that Americans consider fixing their homes when the radon level is between 2 pCi/L and 4 pCi/L. The average concentration of radon in outdoor air is .4 pCi/L or 1/10^th of EPA’s 4 pCi/L action level.

For smokers the risk of lung cancer is significant due to the synergistic effects of radon and smoking. For this population about 62 people in a 1,000 will die of lung-cancer, compared to 7.3 people in a 1,000 for never smokers. Put another way, a person who never smoked (never smoker) who is exposed to 1.3 pCi/L has a 2 in 1,000 chance of lung cancer; while a smoker has a 20 in 1,000 chance of dying from lung cancer. Figure A compares the risks between smokers and never smokers; smokers are at a much higher risk than never smokers, e.g., at 8 pCi/L the risk to smokers is six times the risk to never smokers.

The radon health risk is underscored by the fact that in 1988 Congress added Title III on Indoor Radon Abatement to the Toxic Substances Control Act. It codified and funded EPA’s then fledgling radon program. Also that year, the Office of the U.S. Surgeon General issued a warning about radon urging Americans to test their homes and to reduce the radon level when necessary (U.S. Surgeon General).

Unfortunately, many Americans presume that because the action level is 4 pCi/L, a radon level of less than 4 pCi/L is ‘safe’. This perception is altogether too common in the residential real estate market. In managing any risk, we should be concerned with the greatest risk. For most Americans, their greatest exposure to radon is in their homes; especially in rooms that are below grade (e.g., basements), rooms that are in contact with the ground and those rooms immediately above them.