The World Health Organization said Friday that tiny traces of the chemical melamine are not harmful in most foods, but it joined the U.S. and EU in setting a strict limit that regulators should impose before pulling products off the shelf.

    Melamine was recently found to have contaminated milk products around the world and has been implicated in the sickening of nearly 300,000 babies in China and killing at least six infants there.

    A meeting of food safety experts held by WHO in Ottawa, Canada, decided on Friday that while there is no good reason to have any melamine in food products at all, a maximum of 0.2 milligrams of melamine per kilogram of body weight can be tolerated per day.

    Jorgen Schlundt, WHO's director for food safety, said that threshold is lower than the European Union's limitation of 0.5 milligrams. The U.S. Food and Drug Administration, which originally set its limit at 0.63 milligrams, later reduced its tolerable daily intake to 0.063 milligrams.

    WHO's guidance is used by governments to set their minimum food safety standards.

    Melamine, a nitrogen-rich chemical used in the production of plastics, was first discovered to be a major problem when it appeared in Chinese infant formula in September. Since then traces have been found in milk products around the world.

    Last month the FDA said tests found traces of melamine in the infant formula of one major U.S. manufacturer and cyanuric acid, a related chemical, in the formula of a second major maker.

    Schlundt stressed that the threshold the WHO has set — which stipulates that a 50 kilogram (110-pound) person could tolerate 10 milligrams of melamine per day — is not a "safe" level for melamine, but merely the amount a human being can consume without higher health risk.

    Melamine is used in some food packaging and can rub off into packaged food products. It also is part of a cleaning solution used on some food processing equipment.

    shiweizuzhizhouwubiaoshi，daduoshushipinzhonghanyoudeweiliangsanjuqinganduirentishiwuhaide，dangaizuzhiyumeiguoheoumenggongtongzhidinglejianguanzheyingshishideyangexianliangbiaozhun。

    最近，世界各國的奶製品都被檢測出受三聚氰胺汙染。在中國還致使30萬嬰幼兒生病


，至少6名嬰幼兒死亡。

    世(shi)衛(wei)組(zu)織(zhi)周(zhou)五(wu)在(zai)加(jia)拿(na)大(da)渥(wo)太(tai)華(hua)召(zhao)開(kai)一(yi)次(ci)食(shi)品(pin)安(an)全(quan)專(zhuan)家(jia)會(hui)議(yi)，與(yu)會(hui)人(ren)員(yuan)決(jue)定(ding)，雖(sui)然(ran)食(shi)品(pin)中(zhong)根(gen)本(ben)不(bu)應(ying)存(cun)在(zai)三(san)聚(ju)氰(qing)胺(an)
，但(dan)每(mei)公(gong)斤(jin)體(ti)重(zhong)每(mei)天(tian)最(zui)多(duo)可(ke)以(yi)容(rong)忍(ren)0．2毫克三聚氰胺的攝入。

    世界衛生組織負責食品安全問題的官員約爾根·施倫德表示，這一標準比歐盟0．5毫克的限量更低。美國食品和藥物管理局最初將限量定為0．63毫克，後來將每天可容忍的攝入量降低為0．063毫克。

    各國政府將參照世界衛生組織的標準製定本國的最低食品安全標準。

    三聚氰胺是一種用於塑料產品的富氮化工原料。當9yuefenzhongguodeyingyouerpeifangnaifenzhongfaxiansanjuqingan，renmencaishouciyishidaozhegewentideyanzhongxing。cihou，shijiegeguodenaizhipinzhongdoufaxianhanyouweiliangdesanjuqingan。

    上(shang)個(ge)月(yue)，美(mei)國(guo)食(shi)品(pin)及(ji)藥(yao)品(pin)管(guan)理(li)局(ju)檢(jian)測(ce)後(hou)發(fa)現(xian)，美(mei)國(guo)一(yi)個(ge)主(zhu)要(yao)生(sheng)產(chan)商(shang)製(zhi)造(zao)的(de)嬰(ying)幼(you)兒(er)配(pei)方(fang)奶(nai)粉(fen)中(zhong)含(han)有(you)微(wei)量(liang)三(san)聚(ju)氰(qing)胺(an)
，另(ling)一(yi)個(ge)主(zhu)要(yao)奶(nai)粉(fen)製(zhi)造(zao)商(shang)的(de)配(pei)方(fang)中(zhong)含(han)有(you)與(yu)之(zhi)相(xiang)關(guan)的(de)化(hua)學(xue)物(wu)質(zhi)三(san)聚(ju)氰(qing)酸(suan)。

    施倫德強調世衛組織設定的50公斤（110磅）體重的人每日對三聚氰胺的容忍量10毫克
，並不是一個“安全”標準，隻表示在不產生健康高風險的情況下人體的可消耗量。

    三聚氰胺用於某些食品包裝，並有可能通過摩擦導致食品含有三聚氰胺
，同時也用於某些食品加工設備的清潔液中。