Officials in southern China tested more rice and closed some local mills after the discovery of tainted rice for sale in Guangzhou, which sent some consumers scurrying over the border to Hong Kong to stock up on the staple.
tainted：污染的 scurry：急赶，急跑 stock up：备货，囤货
Food-safety officials in the southern province of Guangdong on Wednesday released the results of tests that showed less than 5% of local rice supplies contained excessive levels of cadmium, a carcinogenic heavy metal that can wreak havoc on the kidneys and weaken bones if ingested in large quantities.
cadmium：镉 wreak havoc on：对...造成严重损害 kidney：肾脏 ingest：摄取，咽下，吸收
Those results contrast with figures published by authorities in the provincial capital of Guangzhou late last week showing high levels of cadmium in almost half of rice samples tested in local markets--a revelation that triggered widespread anger among consumers despite officials' later statements that the sample size was too small and not representative of the city as a whole.
revelation：启示，揭露
In response to the public uproar, health officials in Hunan, the Chinese province that produces the most rice, announced on Tuesday the three local rice mills implicated in the sale of the tainted rice had been ordered to suspend production.
uproar：骚动，喧嚣 implicated：纠缠，有牵连的
All three mills had legitimate production licenses and were operating legally, according to the official Xinhua news agency.
legitimate：合法的，正当的
Rice wholesalers at Sanyanqiao Grain Wholesale Market, one of Guangdong's largest grain markets, had stopped selling rice from Hunan, an executive from the market told The Wall Street Journal on Wednesday.
wholesalers：批发商
'They dare not sell Hunan rice,' the executive said, adding that the market is now selling rice produced in the provinces of Hubei, Jiangxi, Henan and in northeastern areas, together with some imported rice from Vietnam and Pakistan.
Official assurances about the safety of rice in Guangdong did little to soothe anxieties online, where social-media users questioned the validity of the most recent numbers. 'We'll only know the truth when there's an independent investigation,' environmentalist Dong Liangjie wrote on the Twitter-like Sina Weibo microblogging service on Wednesday. 'I'm guessing we're about to see a whole mess of official numbers that show contamination going lower and lower as a way of burying this news.'
assurances：保证，保险 soothe：安慰，平静，缓和 contamination：污染，玷污
Soil contamination has long been an issue in China, were rapid industrialization and lax enforcement of environmental-protection laws have resulted in the pollution of large swathes of arable land with a variety of heavy metals.
swathe：包围，紧绑，大片土地 arable land：可耕地
The issue came to the fore in February after China's Ministry of Environmental Protection rejected a Beijing lawyer's request to see the results of a nationwide soil-pollution survey it launched in 2006, claiming the data was a 'state secret.' The ministry was subsequently hammered by both social-media users and state media for its obfuscation, though it continues to keep the results of the survey secret.
hammered：捶打的，铸打成的
The ministry said earlier this month that it would discuss whether to releas the data after conducting further investigations, according to Xinhua.
Skepticism over the government's claims was on display at an outdoor plaza on the Hong Kong side of the Chinese border on Wednesday, where dozens of shoppers milled around sellers hawking heavy bags of Indian and Thai rice. Buyers ranging from young couples to middle-aged men in shabby suits packed sacks of rice into strollers, while others slung them into backpacks or suitcases with wheels.
Skepticism：怀疑论，怀疑态度 slung：投掷，悬挂
'I bought enough for a month's supply for my family,' said Alin Song, a trader from Shenzhen who said he made the trip to Hong Kong after reading the news about cadmium.
Some users of Sina Weibo tried to discourage shoppers from buying large quantities of rice in Hong Kong, where residents often complain about hordes of mainland Chinese buying up supplies as they pour over the border in search of safer and higher-quality goods. But others joked that a trip to the former British colony might be worth it, despite stiff penalties for carrying more than 15 kilograms of rice out of the city. 'Paying a fine is not a big deal,' wrote one user. 'And if you have to serve a year in jail, then at least you can eat one year of Hong Kong rice--sweet!'
While there is no official data on the prevalence of cadmium-tainted rice in China as a whole, independent studies suggest the problem is widespread. Based on a survey conducted in 2007 and 2008, researchers at Nanjing Agricultural University estimated that roughly 10% of the country's rice supplies contained excessive levels of the poisonous metal.
prevalence：流行，普遍，广泛