Fluorinated liquid-crystal monomers in infant formulas and implication for health risk

• Published in: Environmental pollution (1987) 2024-10, Vol.358, p.124502, Article 124502
• Main Authors: Liu, Runqing, Yang, Runhui, Jiang, Qian, Shao, Bing
• Format: Article
• Language: English
• Subjects: Environmental Pollutants - analysis; Estimated daily intake; Fluorinated liquid-crystal monomers; Food Contamination - analysis; Humans; Infant; Infant Formula - chemistry; Infant formulas; Infant, Newborn; Liquid Crystals; Risk Assessment
• ISSN: 0269-7491; 1873-6424; 1873-6424
• DOI: 10.1016/j.envpol.2024.124502

Fluorinated liquid-crystal monomers (FLCMs), a new class of potential persistent, bioaccumulative and toxic (PBT) emerging pollutants, are extensively utilized in the display panel of various electronic devices. These compounds have been found in various environmental matrixes and dietary. Our previous studies have documented their ubiquitous occurrence in high fat foodstuffs. Infants, a vulnerable group, are more susceptible to the impacts of these pollutants compared to adults. Herein, we provided an assessment of the health risks posed by FLCMs to infants, focusing on their exposure through infant formula. The presence of FLCMs was detected in all infant formulas, with median concentration of 16.5 ng/g dry weight (dw) and the 95th percentile concentration of 65.7 ng/g dw. The most prevalent pollutant in these formulas was 2-fluoro-4-[4′-propyl-1,1′-bi(cyclohexyl)-4-yl] phenyl trifluoromethyl ether (FPrBP), with median and a 95th percentile concentration of 12.2 ng/g dw and 23.8 ng/g dw, accounting for 55.2% to the total FLCMs. Infants aged 0–6 months had the highest estimated daily intakes (EDIs) of FLCMs, with the EDImedian of 267 ng/kg bw/day. FPrBP and 4-[trans-4-(trans-4-Propylcyclohexyl) cyclohexyl]-1-trifluoromethoxybenzene (PCTB) together made up 83.3% of the total EDIs in median exposure scenario of 0–6 months infant. The highest EDI value was 1.30 × 103 ng/kg bw/day, 77.1% of which was attributed to a combination of FPrBP, 4″-ethyl-2′-fluoro-4-propyl-1,1':4′,1″-terphenyl (EFPT), 2-[4'-[difluoro(3,4,5-trifluoro-2-methyl-phenoxy)methyl]-3′,5′-difluoro-[1,1′-biphenyl]-4-yl]-5-ethyl-tetrahydro-pyran (DTMPMDP), 4-[Difluoro-(3,4,5-trifluoro-2-methyl-phenoxy)-methyl]-3,5-difluoro-4′-propyl-1,1-biphenyl (DTMPMDB), 2,3-difluoro-1-methyl-4-[(trans, trans)-4′-pentyl[1,1′-bicyclohexyl]-4-yl]benzene (DMPBB) and PCTB. It's worth noting that FLCMs have higher exposure risk. Based on the threshold of toxicological concern (TTC) method, the EDImedian of FPrBP (183 ng/kg bw/day) and FPCB (3.27 ng/kg bw/day) were beyond their TTC values (2.5 ng/kg bw/day) in 0–6 months infant, implying their prospective health risk. [Display omitted] •The exposure of FLCMs in infant formulas is lower than in breast milk.•FPrBP is the main fluorinated liquid-crystal monomers in infant formula samples.•FPrBP and FPCB may have potential health risk through infant formula intake.