By Gemma Muller | Contributor
A new study suggests millions of microplastic particles, defined as plastic pieces smaller than 0.13 mm, are being swallowed by infants per day from milk bottles; the finding is described as a “milestone” in understanding our exposure to microplastic.
Feeding bottles are typically made from polypropylene plastic, with the main alternative being glass. Plastic is sensitive to heat and physical force, thus the high-temperature sterilisation of plastic bottles and formula milk shaking that is recommended to protect infant health, actually causes microplastics and even nanoplastics to be released from bottles. Raising temperatures to 100°C in accordance with the World Health Organisation (WHO) guidelines, dramatically increases this microplastic release.
Plastic is durable, low-cost, and malleable, with endless varieties of uses that are beneficial to modern day life. But it is well known that plastic contaminates every environment from the deepest oceans to our front door, even human food and drink contains microplastics. Through drinking bottled water, you swallow an estimated 246 microplastic particles per day, compared to 11 particles per day if you drink tap water.
The study goes further to show that food preparation in plastic containers can multiply microplastic exposure thousands of times. Bottle fed babies are estimated to consume 14,600 to 4,550,000 microplastic particles per day through their feeding bottles, this is 2,600 times adult consumption from water, food, and air combined which itself is an underestimate. Even boiling a kettle releases over 10 million microplastic particles per litre.
Infant microplastic exposure is highest in Europe, North America, and Oceania, and lowest in Africa and Asia due to differing bottle preference and breastfeeding rates.
Professor John Boland, at Trinity College Dublin in Ireland, was “absolutely gobsmacked” at the numbers of microplastic particles swallowed by bottle fed babies. He said this exceeded WHOs estimated adult consumption “on the order of a million or millions” but added: “We have to start doing the health studies to understand the implications.”
Microplastics may carry pathogens or leach chemicals added to the plastic itself. Emerging literature reveals potential endocrine (hormonal) disruption or acute toxicity, including the potential to cause cancer. The same may result from plastic monomers, for example bisphenol A (BPA), leached from polycarbonate plastic which leads to metabolic diseases and impacts development and reproduction. The US Food and Drug Administration (FDA) banned the use of BPA in formula bottles for infants under 12 months in 2012, but the European Food Safety Authority still rules the substance safe under current levels, thus the UK remains to use BPA despite the estimated extreme exposure.
Further investigation into the absorption of microplastic particles into the bloodstream and possible health implications is needed. Moreover, this study gives estimates, not measurements of infant exposure levels and thus, changing parents’ behaviours may not be an appropriate next step. However, the study does highlight that microplastics are a bigger problem than we previously realised, leading us to question how they are changing the development of the next generation?