The Environmental Protection Department (EPD) on Friday said less than half of households participating in a trial run of a pay-as-you-throw scheme have been using the designated bags for rubbish disposal.

It said between 20 and 50 percent of households have been making use of the bags since they were given them last month, with the rate even lower in buildings that aren't run by management companies.

However, the department said most of the care homes, restaurants and government buildings taking part in the trial scheme have adopted the designated bags.

Authorities said they are aware that some businesses have seen their operational costs rise due to using the bags and officials will report these concerns to lawmakers on May 27.