When food safety researcher Tianxi Yang became a mother, she wondered how much microplastic her son would ingest when drinking milk out of widely available plastic containers.

She says microplastic exposure and the effects of the tiny particles on human health have been on researchers’ radar for at least a decade.

But testing for microplastics required costly and cumbersome equipment — so Yang set out to create a portable unit that could be used by untrained people at home.