More than two million trees and plants are on display at the massive international horticultural exposition.

Hang Dong district farmer Thong Jailangka fears chemicals will leach into the Taeng irrigation canal that runs through his property.

The Wildlife Fund Thailand shares his anxiety. It said the event organiser never told locals how it planned to manage environmental and ecosystem problems associated with the expo.

Nong Nooch Landscape and Gardening Design - known widely among Thais as Suan Nong Nooch - was hired to landscape the 470-rai site.

A company representative Sunun Phanthurat admitted chemical fertilisers and pesticides had been applied.

However, he said all fertilisers and pesticides were approved by the Agriculture Department.

"Don't worry. We don't use any chemicals that are banned by the department and the volume used is not as high as orchards or vegetable farmers use," he said.

Sunun revealed about five tonnes of chemical fertiliser was applied each month - half the volume of organic fertiliser used.

He said it was difficult to quantify exactly the volume of pesticide used. It cost the company Bt50,000 to Bt80,000 a month in pesticides.

Sunun said environmental and health impacts were points of

concern for the company and the department, which is one of the event's two organisers.

"We don't apply pesticides to the whole area. In enclosed areas like a dome or an air-conditioned room we use only active ingredients extracted from plants, not pesticides," Sunun said.

The international horticultural exposition is due to open next Wednesday.

Before being toppled in a coup, officials from the Thaksin Shinawatra administration

invited agriculture ministers from 60 countries to attend. However, a source at the Foreign Ministry

yesterday said representatives from just seven nations would attend. They were Malaysia, Cambodia and five African states.

Pennapa Hongthong

The Nation