The practice of adding the industrial chemical melamine to milk 'has existed for a long time in this industry.

郭浩说，在牛奶中添加三聚氰胺化工原料的做法在业内早已有之。

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List of substandard milk powders: People searched for this after learning that many brands of milk powder had been laced with melamine, a toxic industrial chemical.

不合格奶粉名单：了解到多个品牌的奶粉掺加了有毒化工原料三聚氰胺的消息后，人们纷纷上网搜索这一名单。

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It recently launched four agro-industrial businesses supplying staple products such as milk and maize flour, and its retail-food chain, Mercal, aims to cover 60% of the market.

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Investigators said the industrial salt nitrite had been added to fresh milk at two dairies in the north-western Gansu province in order to harm people.

BBC: Milk poisoning in northwest China 'deliberate'

Similar worries seem to have prompted the arrest in November of Zhao Lianhai, who had been campaigning on behalf of the parents of some 300, 000 children who were affected by milk powder tainted with melamine, an industrial chemical, in 2008.

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