Tuesday, July 29, 2014
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当技术恐惧症变得有害之时

发自斯坦福——1990年代末期在全球范围内出现了一个特殊的现象。众多食品与饮料生产企业一个接一个地屈服于抗议分子的压力之下,向一个充满前景的新技术——通过基因工程使植物生产出特定成分——说不。而时至今日,这种状况还依然在持续。

日本酿酒商麒麟和丹麦酿酒商嘉士伯都将基因改造成份排除在自产的啤酒之外。在美国,快餐连锁巨头麦当劳的餐单中,食品生产商亨氏还有盖博(当时还是瑞士Novartis公司的一部分)的婴儿食品系列里都不见基因改造成份的身影;零食生产商Frito-Lay也要求为其供应原料的种植者停止种植某一品种的玉米,因为其含有一种通过基因工程改造过的用以防止害虫侵袭的细菌蛋白。

人们列举了许多种理由来证明上述措施是有必要的,但事实上在向一小撮狡猾的抗议分子屈服的同时,这些企业转而选择向消费者提供更不安全的食品,并因此将自身暴露在法律风险之下。

每一年都有无数的包装食品因为含有昆虫尸体、有毒霉菌,细菌和病毒等“全天然”成份而被暂停上市或者召回。这是因为种植业大多在尘土飞扬的露天环境中进行,自然也无法避免这类污染。几个世纪以来,大规模食物中毒事件的最大元凶往往是真菌毒素对未处理谷物的污染——当昆虫侵袭农作物并造成伤口,令真菌(霉菌)得以附着之时,这一风险也随之急剧扩大。

比如说,伏马菌素(fumonisin)以及其他真菌都拥有极强毒性,不但会使人类罹患食道癌,还能令其他食用玉米的牲畜患上致命性疾病。伏马菌素还会阻止细胞对叶酸(一种维生素)的吸收,增加发育中的胎儿出现神经管缺陷的风险,一旦摄入了这类毒素,即便一个人的日常食谱中已经含有足量的该类维生素,也会出现叶酸缺乏症——甚至脊柱裂这样的缺陷。

许多监管机构都因此设立了玉米制食品和饲料中允许存在的伏马菌素最高含量。而达到这些标准并防止摄入真菌毒素的常规做法仅仅是对那些已经/未经处理的谷物进行检查,并抛弃受污染的那部分——但该办法一方面效率很低,另一方面也经常出现纰漏。

而当今科技——尤其是借助DNA重组技术(也就是植物生物技术或者基因改造)的基因工程改造植物——为这个问题找到了一条解决的途径。虽然那些食品生物技术反对者们对基金改造作物大肆抨击,认为它们存在引入新变应原或者毒素的风险(即便无一得到证实),但这类产品却能令食品工业切实有效地从源头上杜绝真菌污染。

其中一个绝佳例子就是那些被植入了来自某种无害细菌的一个或多个基因的商业化玉米品种。这些细菌基因的表达会生成一些只对玉米害虫有毒,却对鸟类鱼类以及包括人类在内的哺乳动物无害的蛋白,当这类玉米将害虫拒之门外的时候,自然也能降低镰孢霉菌的感染程度,从而减低伏马菌素的含量。

事实上,艾奥瓦州立大学以及美国农业部的研究人员都发现这类改造玉米的伏马菌素含量最高能实现80%的下降。同样一项意大利研究也发现,用可以生成抗害虫细菌蛋白的基因改造玉米喂养的断奶小猪,与那些用未经过改造的同一品种喂养的小猪相比,体内的伏马菌素水平更低。更重要的是,在进食量相同的情况下,改造玉米喂大的小猪体重更重,说明其健康状况更佳。

考虑到基因改造农产品在健康方面的好处——更不用说其更高也更可靠的产量——各国政府都应当引入法案促进这类基因改造谷物以及其他作物的推广。此外也希望公共卫生倡导者们能呼吁种植这类作物并将其加工成食品,就像用氯来为自来水消毒并加入少量氟(以防止儿童蛀牙)那样。那些致力于向消费者提供更安全更优质食品的生产商也应该努力让基因改造产品进入市场。

但遗憾的是,上面没有任何一件事情能成为现实。抗议分子继续将嘈杂而挥之不去的反对之声施加于基因改造食品上——虽然他们20多年的抗议也无法阻止这些技术带来的极大好处:人们得以减少化学杀虫剂的使用(冲刷入河的化学物也随之减少),更多地使用农业技术操作来防止土壤退化,农民收入增加,真菌污染程度也有所降低。

为了回应这些抗议分子的奇谭怪论,政策制定者们将基因工程农作物的测试和商业化都置于毫无科学依据且异常严厉的监管之下,并导致了可怕的后果。一项对农业生物技术的政治经济影响的突破性研究发现过度监管导致“得到证实的技术在全球范围内的扩散速度减慢,引发世界食品供应量增速偏低以及更高昂的食品价格”。当前的政策同时也“阻碍了对进一步技术研究和发展的投资,因此减缓了预计将为消费者和环境带来更广泛好处的第二代技术方面的创新。”

每个牵涉到食品生产和消费的人都因此而受害:消费者们(尤其是发展中国家)面临着本可避免的健康风险,食品生厂商们则只能销售那些有“设计缺陷”的产品并随时可能背上官司。

由此可见,那些敌视并压制在食品生产方面的重要革新的公共政策并不是真心维护民众利益的政策。

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  1. CommentedNijaz Deleut Kemo

    Dear Henry,
    Recent developments in EU Environmental Law and Policy are: First is, European Court of Justice (ECJ) Case: C-58/10 until 68/10, Monsanto SAS and others 22/03/2011., it is about preliminary ruling on GMO crop emergency measures in France, and concerned a ban isued by France on cultivation of the GMO corn crop MONO810. Advocate General (AG) Mengozzi concluded that emergence measures can only be taken in cases where the risk is considerable. "The PRECAUTIONARY PRINCIPLE however tells that precautionary MEASURES can be taken in case where science is not (yet) able to assess the PROBABILITY RISK AT HAND. The second is, European Parliament (EP) backs national right to cultivation bans. If the Council manages to find common position, this balanced agreement will allow Member States and regions the RIGHT TO NOT GROW GMOs if they so choose. So, I'm pleased about this development, too. The Commission has proposed to grant EU Member States the right to ban crops on all but health or environmental grounds, which were to be solely assessed by the European Food Safety Authority. An EU-level safety checks and authorization will continue to be a precondition to a green light for growing GMOs, and its guidelines need updating. Austria, France, Greece, Hungary, Germany and Luxembourg have activated a "SAFEGUARD CLAUSE", so far. That is, and that is good enough, I do hope, for both sides in this issue of public concern for years.

  2. CommentedWilliam Wallace

    I confess I am of two minds on genetic engineering.

    In its simple, straight-forward presentation in non-technical journals, recombining genes seems as simple and potentially innocuous as changing one lego block for another, without non-local impacts on the entire "structure."

    Yet I continue to come across science news that portrays many biological processes as as multi-genetic in nature. This seems to imply that switching out one gene can not only affect its primary function, but have unintended collateral effects. Further, iirc, plants often "innovate" genetically by incorporating DNA from other plants, thus giving plants their characteristic prolific chromosome nature (e.g. adders-tongue). So, a gene that is non-plant in origin that becomes artificially entwined in the plant kingdom could have potentially nightmare consequences on one or more ecosystems, especially after species-hopping.

    Genetic engineering really needs some intermediate-level discussion beyond what is presented in popular science articles so that non-specialists can benefit from a more informed discussion. Until then, I am not easily reassured of the intended, and unintended, consequences of this technology.

      CommentedJose Azevedo

      Good point! I hate simplistic views on how technology is so good, how come these ignorant people not see it? Did you noticed the choice of words? "disingenuous activists", all, bleating irrationalities and causing over-regulation. One can almost hear a secret wish that they all get fumonisin cancer and die.

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