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作者：呂聰 來源：農藥工業網 日期：13-12-02
去年《食品化學毒物學》一篇關於轉基因玉米致癌的文章，鬧得滿城風雨，被反轉基因派當做至尊法寶到處傳播，在文章發表后不久就有無數科學家對此提出質疑，正式提出反對意見並被《食品化學毒物學》當做讀者來信發表的就有10多篇。
具體見http://www.sciencedirect.com/science/article/pii/S0278691512005637
這篇論文導致了大量不明真相的民眾對轉基因食品的恐慌，而鏈接中則是科學家與讀者來信質疑這篇文章中數據和實驗方法的問題。其中包括：①鼠種存在問題；②樣本量太少，每種性別只設置9個實驗組和1個對照組這種做法缺乏可信性；③塞教授公布的資料有限，特別是有關實驗鼠的餵養細節不得而知（言下之意就是餵養方式不同也可能導致結果不同）且塞教授在論文發表后沒有應要求提供這些數據；④塞教授的統計方法有問題；⑤統計過程中一些數據欠缺。
11月29日，《食品化學毒物學》主編正式宣布在通過長時間的調查研究后，認為文章的數據不能支持結論，正式撤回該篇文章：http://www.elsevier.com/about/press-releases/research-and-journals/elsevier-announces-article-retraction-from-journal-food-and-chemical-toxicology
2012年11月，《食品化學毒物學》發表了論文《抗農達除草劑的轉基因玉米對大鼠的長期毒性》，在論文發表的短時間內，雜誌的主編收到大量讀者來信，質疑研究中的數據問題和實驗設計問題，甚至有人指控作者欺詐，並呼籲編輯撤稿。
編輯向原作者要求提供實驗原始數以供調查，經過同行評審和數據分析后，編輯並沒有發現該實驗存在數據造假或者學術不端行為，但是試驗樣本數量存在過小的問題在同行評議中引起了關注，並且實驗數據也不足以反映轉基因玉米確實存在毒性的明確結論，同時，鑒於該實驗中使用的老鼠品系本來就是易感癌的品系，因此不能排除只是正常情況下引起的癌症，這些問題雖然不是學術不端，但是卻是作為一篇論文的致命缺陷。
最終的結論是，該文章的結論極不嚴謹，不能達到該雜誌的發表標準，同行評審過程並不完美,但是同行評審過程卻能讓文章更加嚴謹，讀者和作者之間的交流和質疑也有助於學術的發展。於是，《食品化學毒物學》雜誌決定對該文章予以撤稿。
對於撤稿事件，該文章的作者，塞拉利尼團隊隨即做出了回應，聲明稱：
我們是FCT一年多前發表的論文的作者，關於農達和耐受農達的轉基因生物的事（塞拉利尼等2012）。對於同樣的質疑，我們已經在同一個刊物上回應過（塞拉利尼等，2013），即：作為正常的科學辯論，僅僅由於實驗鼠品系的選擇和數量的原因，就判定研究結果「結論不完整」，這是不能接受的。我們堅持我們的結論。我們早已公布了對相同的質疑所做的回答，但至今沒有見到對我們的任何回應（塞拉利尼等，2013）。
We, authors of the paper published in FCT more than one year ago on the effects of Roundup and a Roundup-tolerant GMO (Séralini et al., 2012), and having answered to critics in the same journal (Séralini et al., 2013), do not accept as scientifically sound the debate on the fact that these papers are inconclusive because of the rat strain or the number of rats used. We maintain our conclusions. We already published some answers to the same critics in your Journal, which have not been answered (Séralini et al., 2013).
在該篇聲明中，塞拉利尼團隊還就文章中反對者們所質疑的幾點問題做出了相應回答，
關於實驗大鼠品系
同一個大鼠品系，被用在研究致癌性和慢性化學毒理學的美國國家毒理學項目中(King-Herbert et al., 2010)。SD大鼠是常規性用於毒理和致癌效果實驗中的動物，其中有孟山都公司的90天實驗被當做批准NK603轉基因玉米應用的依據，其他轉基因農作物的相關實驗也都採取了類似做法(Sprague Dawley rats did not came from Harlan but from Charles-River) (Hammond et al., 2004; Hammond et al., 2006a; Hammond et al., 2006b)。
Rat strain
The same strain is used by the US national toxicology program to study the carcinogenicity and the chronic toxicity of chemicals (King-Herbert et al., 2010). Sprague Dawley rats are used routinely in such studies for toxicological and tumour-inducing effects, including those 90-day studies by Monsanto as basis for the approval of NK603 maize and other GM crops (Sprague Dawley rats did not came from Harlan but from Charles-River) (Hammond et al., 2004; Hammond et al., 2006a; Hammond et al., 2006b).
我們可以提供一份文獻清單，表明在同行評審的雜誌上SD大鼠被用在36個月(Voss et al., 2005)或24個月的實驗(Hack et al., 1995,Minardi et al., 2002, Klimisch et al., 1997,Gamez et al., 2007.)中，其中有一些文章就發表在FCT上。
A brief, quick and still preliminary literature search of peer-reviewed journals revealed that Sprague Dawley rats were used in 36-month studies by (Voss et al., 2005) or in 24-month studies by (Hack et al., 1995), (Minardi et al., 2002), (Klimisch et al., 1997), (Gamez et al., 2007).Some of these studies have been published in Food and Chemical Toxicology.
Number of rats, OECD guidelines
實驗動物數量與OECD實驗規範
OECD實驗規範：第408條，關於90天實驗，第452條關於慢性毒性試驗，第453條關於綜合致癌性/慢性毒性試驗，都要求用20隻動物為一組(1981和2009的規定都這樣要求)，儘管可以用10隻動物的實驗就能取得生物化學參數。我們做的是長期毒性研究而不是致癌性研究，從一開始就不是這樣設想的。根據常規10隻動物一組已經足夠在生物化學水平上進行研究，我們測量的參數數量是非常大的。
OECD guidelines (408 for 90 day study, 452 chronic toxicity and 453 combined carcinogenicity/chronic toxicity study) always asked for 20 animals per group (both in 1981 and 2009 guidelines) although the measurement of biochemical parameters can be performed on 10 rats, as indicated. We did not perform a carcinogenesis study, which would not have been adapted at first, but a long-term chronic full study, 10 rats are sufficient for that at a biochemical level according to norms and we have measured such a number of parameters!
在我們的實驗中，性激素干擾的參數以及其它參數對於解釋一年之後的嚴重後果是充分的。我們採用的OPLS-DA統計方法是最適宜的。關於腫瘤和動物死亡，時間效果以及每隻動物的平均腫瘤數量都必須被納入分析。在風險研究中出現的每一個現象，都必須予以充分重視。孟山都公司的研究用了同樣的大鼠品系，每組僅10隻衡量20個參數，就得出同一種NK603轉基因玉米「安全」的結論，而且他們的實驗只做了3個月 (Hammond et al., 2004)
The disturbance of sexual hormones or other parameters are sufficient in themselves in our case to interpret a serious effect after one year. The OPLS-DA statistical method we published is one of the best adapted. For tumours and deaths, the chronology and number of tumours per animal have to be taken into account. Any sign should be regarded as important for a real risk study. Monsanto itself measured only 10 rats of the same strain per group on 20 to conclude that the same GM maize was safe after 3 months (Hammond et al., 2004).
The statistical analysis should not be done with historical data first, the comparison is falsified, thus 50 rats per group is useless
統計分析不應該先做歷史數據，用這個方法做比較研究是錯誤的，用每組50隻動物做研究是沒有意義的。
採納歷史數據會把健康風險評估變成研究造假，因為食譜中的材料已經受到化學污染(by dibenzo-p-dioxins and dibenzofurans (Schecter et al., 1996)和汞污染(Weiss et al., 2005)，鎘污染，鉻污染等，污染的程度足以改變動物肝臟和肺臟的基因表達，足以擾亂基因分析(Kozul et al., 2008)。以往的食料中還發現農藥和增塑劑污染，污染來自箱籠或者水(Howdeshell et al., 2003)。歷史數據也有來自可能食用了轉基因的動物，很多地方的鼠糧中的確發現了轉基因成分。這一切都與污染水平相關，我們已經在實驗大鼠和對照組大鼠中檢測到了這些問題。
The use of historical data falsifies health risk assessments because the diet is contaminated by dibenzo-p-dioxins and dibenzofurans (Schecter et al., 1996), mercury (Weiss et al., 2005), cadmium and chromium among other heavy metals in a range of doses that altered mouse liver and lung gene expression and confounds genomic analyses (Kozul et al., 2008). They also contained pesticides or plasticizers released by cages or from water sources (Howdeshell et al., 2003). Historical data also come from rats potentially fed on GMOs, some animal pellets in the world do indicate that. All that corresponds to the contamination levels for which we have detected some effects in our treated rats versus appropriate controls.
在歷史數據中，2年SD雌性大鼠罹患乳腺纖維瘤的為13%~62%(Giknis, 2004)，但在我們的實驗中對照組的發病率要低得多，這才是真正的對照，而我們的實驗鼠發病率比對照組高很多，這使得我們的研究結果有顯著性。動物的死亡率也是這樣。
2-year historical data mammary fibroadenoma rate from Charles River SD females ranged from 13 to 62% (Giknis, 2004). We obtain a lot less in our controls, the real comparators, a lot more in treated rats. This makes our results significant, like for deaths.
Double standards 雙重標準
遵循同一個邏輯把塞拉利尼的實驗和孟山都公司的實驗做一對一的比較，如果前者的實驗不足以顯示危害，那麼後者的實驗也不能證明其安全。
A factual comparative analysis of the rat feeding trial by the Séralini』s group and the Monsanto trials clearly reveals that if the Séralini experiments are considered to be insufficient to demonstrate harm, logically, it must be the same for those carried out by Monsanto to prove safety.
以往的研究發現凡是顯示轉基因農作物有負面效果的，都會被監管者從實驗到統計方法做嚴格的重審，凡是聲稱轉基因農作物安全的研究，都被照單接受。只要是沒有報告負面效果的研究，無論他們的研究方法有何種不足，都被接受為「安全」的證明。
Basically, all previous studies finding adverse effects of GE crops have been treated by regulators with the attitude: only those studies showing adverse effects receive a rigorous evaluation of their experimental and statistical methods, while those that claim proof of safety are taken at face value. All studies that reported no adverse effects were accepted as proof of safety regardless of these manifest (but deemed irrelevant) deficiencies of their methods.
來自(Snell et al., 2012) 的一份文獻概覽研究可以說明這個傾向。如作者在摘要中這樣說，「在這裡的24項研究的結果都不能顯示存在任何健康危害問題…」，然而在文章中卻指出，研究報告的作者們留下了無數缺陷，同他們指責塞拉利尼論文的問題類似，或更加嚴重。例如24篇中16篇(67%)文章沒有交代對照組飼料是否與實驗用的飼料屬於同基因品種(他們的解釋只是「沒有採用」)。許多篇文章連討論所用的方法都沒有介紹。此外還有其他被指出的缺陷。
The review by (Snell et al., 2012) illustrates this issue. In the abstract, the authors state "Results from all the 24 studies [reviewed] do not suggest any health hazards [...]" – taking all those studies at face value. Yet in their review, the authors find numerous weaknesses of similar or greater severity [than those] raised for the Séralini groups paper. For example, of the 24 studies they evaluated 16 (67% of all studies) did not mention using the isogenic line as control (interpreted as having not used them), many did not describe the methods in any detail, and according to the reviewers had other deficiencies too.
基於完全相同的原因，FCT應該把Hammond 等人關於耐受農達轉基因玉米的那些論文全都撤回。那些論文貌似都是真正的科學討論，然而實際上發表它們只是為了給孟山都提供權威證據。
FCT should retract the Hammond et al. paper on Roundup tolerant maize for all these reasons, published for Monsanto』s authorization, or consider that each of these papers is part of the scientific debate.
註： 本帖和新鮮人的前一帖有明顯的不同，可見寫帖子的人其實都有傾向性！！！ |
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