Re-using plastic bottles increases leaching of toxic chemicals

RE-USING plastic bottles causes dangerous chemicals to be leached into the fluid they carry, a joint study by the Harvard School of Public Health and the Cyprus University of Technology (TEPAK) has shown.

The research, published in this year’s Water Research journal, showed that repeated use of PET and PC bottles increases leaching of the toxic chemicals antimony and bromine, the last used as a flame retardant. 

This was irrespective of whether or not the bottles were exposed to high temperatures or UV radiation, till now considered the main agents for plastic constituents leaching into water.

The research team analysed water in plastic bottles which were reused up to 27 times; 19-litre bottles are often reused much more. 

Antinomy leaching into bottles can disrupt the endocrine system, the glandular system producing body-regulating hormones. 

The levels of antimony found did not pose serious health risks according to currently acceptable intake estimates, but researchers said regulatory agencies were looking into revising those standards. 

The proposed revisions are based on new findings, including in-vitro studies finding increased proliferation of breast cancer cells when antinomy is present in the human system. 

“In the case of bromine, there is no acceptable daily dose estimates, so we can’t be sure how they impact public health,” researcher Kostantinos Makris of TEPAK said. 

Although the researchers examined bottles reused up to 27 times, many are actually in use until visibly aged. 

One company in Limassol reuses bottles up to 50 times, blasting them with sodium hydroxide and hydrogen peroxide at 75 degrees Celsius to clean them. 

“Standards vary from company to company,” Makris said, adding that “we are only now beginning to look at the health consequences of plastic bottles”. 

Health Services head Christos Christou said that as a general principle they checked bottles for any kind of leaching, with the goal “to prevent (any) chemical leaching whatsoever”.

He said his colleagues would study the research and see if any immediate measures needed to be taken in conjunction with the state lab, but added health services in any case ran precautionary checks in accordance to EU regulations. 

“We have not come across anything worrying, but we will take further action if necessary,” he added. 

Contact details for the public to report any problems to the health services department can be found at www.moh.gov.cy.

 For his part, Makris said tap water in Cypriot cities was at a “satisfactory level” of hygiene and people could freely use it. 

Nonetheless, he advised the public to be cautious and avoid excessively reusing plastic bottles.