South China's Hainan Province has taken measures to boost vegetables' safety after a toxic pesticide was found in cowpeas grown in the region, officials said Thursday.

The province is closely monitoring all cowpea production bases and collection stations after Isocarbophos, a highly poisonous pesticide, was detected in sample tests carried out in markets in central China's Hubei Province, south China's Guangdong Province, and east China's Anhui Province.

Earlier this month, about 3.5 tons of Hainan cowpeas were found tainted with the poison in Wuhan, capital city of Hubei Province.

The city responded by destroying all 3.5 tons of the cowpeas and prohibiting further Hainan-produced cowpeas from entering the city's markets.

Tests on Hainan cowpeas were later carried out nationwide.

In Guangzhou, capital city of Guangdong Province, many citizens said they would not eat cowpeas for a while.

Unlike Wuhan, Guangzhou didn't ban the sale of Hainan cowpeas. Local authorities there said there was no legal justification for such action and doing so would be "risky."

Local food safety authority has urged strict inspection and tests on fruits and vegetables sold on local markets.