Opening plastic bags, bottles generate microplastics: Study

Opening chocolate packs, plastic bags and bottles is contributing to the generation of microplastics -- small plastic particles less than 5 millimetre long -- during daily tasks, according to a study.

Researchers from the University of Newcastle in Australia noted that microplastics are generally believed to originate directly from industry, for example as cosmetic exfoliates, or indirectly from the breakdown of larger plastic items over time.

However, the contribution of daily tasks such as cutting, tearing or twisting open plastic packaging and containers has not been fully understood.

The study, published in the journal Scientific Reports, monitored the generation of microplastics during the tearing open of chocolate packaging, cutting of sealing tapes and opening of plastic bottle caps.

The generation of microplastics during these processes was confirmed using chemical tests and microscopy, the researchers said.

They found that different shapes and sizes of microplastics were generated during tearing or cutting. These included fibres, fragments or triangles, ranging from nanometres to millimetres in size. Fragments and fibres were generated most often.

The researchers estimated that 10 to 30 nanogrammes of microplastics may be generated per 300 centimetres of plastic during cutting or twisting, depending on the opening approach and conditions of the plastic, such as stiffness, thickness or density.

The results suggest that everyday activities such as opening plastic bags and bottles could be additional sources of small quantities of microplastics.

However, their risk, possible toxicity and how they may be ingested are not yet resolved and further research into human exposure is needed, according to the researchers.