Taiwan Cement came under pressure to reassure customers that the company's products meet quality safety standards after former Hualien County Council speaker Lai Chin-kun was charged with fraud for supplying raw materials mixed with industrial waste between 2010-15.

Lai's family operates Wen Hao Co, Jian Dong Mining Co and several other companies in Hualien County that are mainly involved in mining and quarrying raw materials. The company, which also operates a soil and earth materials dump site, in 2010 secured a contract with Taiwan Cement to supply clay, sand, limestone and other raw materials that are used for producing cement mix.

When supplying raw materials to Taiwan Cement, prosecutors said that Lai instructed company drivers to fill the bottom half of the trucks with industrial waste and place natural materials, such as clay, sand and limestone, on the top half, prosecutors said.

Taiwan Cement officials yesterday said that the company's cement mix conforms to quality and safety standards, adding that strict inspections are carried out on all incoming raw materials, including taking random samples of the top and bottom layers of delivery trucks from suppliers.