The gradual re-emergence of plastic bag litter countrywide this summer has led to calls by an environmental organisation for a doubling of the tax levy.
Friends of the Earth director Oisín Coghlan said there is increasing evidence to suggest that the "shock factor" of having to pay for plastic bags has now diminished, amid increasing sales of plastic bags. He said increasing the levy would curb complacency and reduce the number of plastic bags sold.
Despite record low sales of 85 million bags following the introduction of the 15 cent levy in March 2002, some 115 million bags were sold last year, with that figure set to increase to 130 million by the end of 2006, according to Mr Coghlan.
The re-emergence of the plastic bag is reflected in the levies collected by the Department of the Environment, which have increased from €7 million in 2002 to €17 million last year.
By this May, the department had collected almost €9 million, indicating that 2006 could be a record year for levies collected and plastic bags sold.
Despite evidence to suggest that customers are abandoning the routine of taking their recyclable bags to the shops and that the litter scourge of plastic bags in trees and rural settings is returning, most supermarkets report no increase in the sale of plastic bags.
Superquinn, the first supermarket in Europe to introduce a reusable green bag in 1997, says that since the introduction of the levy, their supermarkets have recorded a 96 per cent reduction in plastic bag usage, the equivalent of 70 million plastic bags per annum.
Despite the successes of the initiative, however, Friends of the Earth have proposed a doubling of the levy from 15c to 30c.
"The best way to refocus the minds of retailers and consumers on the importance of the tax is to increase it substantially," Mr Coghlan said. "This is one of the few taxes you are not supposed to pay, you are supposed to avoid it.
"The tax was designed to change behaviour, not to raise revenue, yet the amount of money flowing to Government from the levy has now passed €50 million. There's a danger they will get used to it. Government needs to raise the tax enough to put people off paying it again."
Before the summer recess Minister for the Environment Dick Roche signalled that the levy may be increased to 19 cents in an effort to ensure that the public does not become "complacent".
A spokeswoman for Mr Roche said legislation would only allow for a 4c increase but if this failed to have the "desired effect", the Minister would proceed to change legislation so as to increase the levy.