Assessing microplastic contamination and health risks in infant formula: A case study from Turkey

Abstract

Microplastic (MP) contamination is an emerging concern for food safety and infant health. This study provides the first systematic assessment of MPs in infant formulas marketed in Turkey. A total of 36 samples from 12 commercial brands were analyzed using stereomicroscopy and micro-Raman spectroscopy. Analyses were performed with 532 and 785×nm lasers, 50 × magnification, 10 s exposure, a 300–3200 cm−1 spectral range, and gratings of 600/1200 l/mm. Suspected particles were compared against the ST-Japan MP library, with a ≥70 % spectral match threshold applied for polymer identification. MPs were detected in 100 % of samples (n = 36), with 97 % of particles successfully characterized. Concentrations ranged from 14 to 52 MPs/100 g (mean 31.3 MPs/100 g). Fibers were the dominant form (58 %), followed by fragments and films. Nine polymers were identified, with polyethylene (PE), polyethylene terephthalate (PET), polypropylene (PP), and polyamide (PA) most abundant. Packaging materials, manufacturing processes, and feeding equipment were identified as likely contamination sources. Estimated daily intake for infants aged 0–6 months averaged 5.64 MP/kg bw/day (∼15,400 MPs annually). This annual exposure estimate was calculated based on an assumed body weight of 7.5 kg for a 6-month–old infant and a daily formula consumption of 135 g, as recommended in previous nutritional intake assessments. To enhance toxicological relevance, mass- and surface–area–based exposures were also calculated, averaging 326.77 μg/kg bw/day and 0.009 cm2/kg bw/day, respectively. The polymeric risk index (pRi) ranged from 8.27 to 1647.65 (mean 472.12), classifying 50 % of samples as low risk, 33.3 % as high risk, and 8.3 % as very high risk. These findings confirm infant formulas as a consistent source of MP exposure and highlight the need for stricter production and packaging controls to reduce early–life risks.