Representatives of the cosmetics and detergent industries have claimed that proposals to ban plastic microbeads are too broad and would prevent them making products allowed in other EU countries.
The Irish Cosmetic, Detergent and Allied Products Association (ICDA) also said that the cosmetics industry in Europe had already phased out more than 97pc of plastic microbeads used in exfoliating and cleansing products and was on target to achieve 100pc by 2020.
The remarks came as an Oireachtas committee examined a proposed law prohibiting certain products containing the microbeads, which are not biodegradable and can end up in the food chain when eaten by fish.
Dr Kevin Lynch, head of geography at NUI Galway, told TDs and senators that evidence of microplastics was being found in Ireland's coastal and marine environments. He said the bill looked like it would be a good addition to attempts to reduce the proliferation of plastics in the environment.
Galway Mayo Institute of Technology academic Dr Róisín Nash told the committee that low levels of microplastics had been found in the intestinal tracts of fish from Irish coastlines.
ICDA director Siobhán Dean said the cosmetics and detergent sector took the issue of plastic aquatic litter seriously and shared the goals of the Irish Government and the EU to address this challenge.
She said that Cosmetics Europe recommended to its members in 2015 that they discontinue the use of plastic microbeads in cleansing products by 2020.
Ms Dean said any proposed ban on microbeads must be supported by clear definitions to operate effectively. She argued that the definition in the proposed law was "too broad" and "as a result would prevent Irish manufacturers manufacturing rinse-off cosmetics and detergents products that otherwise would be permitted in other EU countries".
She said: "It would also remove many products on the Irish market until the products are reformulated."