Tea cup
Tea cup (Representational picture) Pixabay

Tea drinkers could be consuming more than they bargained for in their brew as a single plastic tea bag is estimated to shed billions of microplastic particles, a study has revealed.

A plastic tea bag releases about 11.6 billion microplastics and 3.1 billion smaller nano plastic particles when it is steeped into a cup of boiling water, said researchers from McGill University in Canada.

"The levels of nylon and polyethylene terephthalate particles released from the teabag packaging are several orders of magnitude higher than plastic loads previously reported in other foods," suggested the study published in the journal of Environmental Science and Technology.

The researchers called for more investigation into the health effects of microplastics -- less than 5mm, which are invisible to the naked eye.

Microplastics are widely found in the environment, in tap and bottled waters, as well as, food items. They are being consumed by humans for decades and there is no reliable information on adverse effects of plastic particles, particularly the nano-size particles on human health, according to a WHO report.

Calling for greater research, the report, however, argued the findings were based on "limited information" and there were "no studies on the impacts of ingested microplastics on human health".

Researcher Laura Hernandez said that the finding was a chance for consumers who are looking to reduce their plastic use to be more aware of their purchases.

"There is really no need to package tea in plastic, which contributes to you not just ingesting plastic but to the environmental burden of plastic," she said.

According to another research, an average person ingests about 50,000 particles of microplastic annually and between 74000 and 121000 when inhalation is considered.