Risk assessment of dietary exposure to 3-monochloropropane-1,2-diol esters in infant formula powders in Shanghai / 环境与职业医学

Background Chloropropanol esters (MCPDE) have attracted much attention in recent years as a kind of new contaminant found in various refined oils. The pollution of 3-monochloropropane-1,2-diol esters (3-MCPDE) is the most prominent. 3-MCPDE is hydrolyzed in organisms to 3-monochloropropane-1,2-diol which has been shown to have reproductive toxicity, nephrotoxicity, and potential carcinogenicity. Infant formula powders can be polluted by 3-MCPDE when refined edible oils are added during production. Objective To assess the risk of exposure to 3-MCPDE related to the consumption of infant formula powders for children aged 0-3 years in Shanghai market using the food consumption data and the data of 3-MCPDE contamination in these foods. Methods Gas chromatography-mass spectrometry was used to determine 3-MCPDE in 133 samples of infant formula powders in Shanghai. Using a multistage stratified random sampling method, a total of 807 infants and toddlers aged 0-3 years were randomly selected from each district/rural/town in Shanghai, including 208 children aged 0-6 months, 276 children aged 6-12 months, and 323 children aged 12-36 months. The food consumption data was investigated using food frequency questionnaire (FFQ) distributed by combining telephone inquiries and face-to-face interviews among guardians. Population's probability distributions of 3-MCPDE exposure were assessed by @Risk 7.5 software and Monte Carlo simulation algorithm. According to the dietary intake assessment model and the tolerable daily intake (TDI) of 3-MCPDE of 2.00 μg·(kg·d)−1 proposed by the European Food Safety Authority (ESFA), a risk assessment of exposure to 3-MCPDE was conducted for infants and toddlers aged 0 to 3 years old in Shanghai who consumed 3-MCPDE via infant formula powders. Results The average concentration of 3-MCPDE in 133 samples of infant formula powders was 0.115 mg·kg−1 with a positive rate of 100.00%. Among different types of formula powders, infant formula powders for infants of 0-6 months had the highest concentrations of 3-MCPDE and fat [0.136 mg·kg−1 and 25.2 g (per 100 g sample) in average respectively]. There was a positive correlation between fat concentration and 3-MCPDE concentration in the samples (r=0.438, P<0.05). The average consumption of infant formula powders of 807 infants aged 0-3 years was 88.3 g·d−1. Among all investigated age groups, the average consumption of infant formula powders by infants aged 0-6, 6-12, and 12-36 months was 87.7, 98.3, and 80.1 g·d−1 respectively. The dietary exposure to 3-MCPDE from infant formula powders of infants aged 0-3 years averaged 0.83 μg·(kg·d)−1 for general intake level or valued 1.44 μg·(kg·d)−1 using the 95 percentile for high intake level. Exposure decreased with increasing age and was highest in infants 0-6 months of age, whose general and high intake levels were 1.41 and 2.34 μg·(kg·d)−1, respectively. The risk population defined with the exposure higher than the TDI proposed by EFSA were proportioned to be 13.90% and 0.50% in infants aged 0-6 months and 6-12 months respectively, indicating a risk that cannot be ignored, and no risk in infants aged 12-36 months. Conclusion Among the investigated infants aged 0-3 years in Shanghai, those aged 0-6 months are at a high risk of exposure to 3-MCPDE. In view of the sensitivity of infants to pollutant exposure, the risk of exposure to 3-MCPDE should be highly concerned.

Characteristics on the oxidation stability of infant formula powder with different ingredients during storage.

Infant formula powder is prone to oxidation reaction during storage, which leads to the decrease of milk powder quality. The whole milk powder (WMP) was formulated, and the characteristics of infant formula powder were tracked during storage. The addition of metal ions, polyunsaturated fatty acids, and vitamins could reduce the peroxide value and increase the thiobarbituric acid value in the infant formula powder during the early stage of storage. When the samples were stored for 6 months, the free fat content of the base milk powder and the sample added with metal ions had high level (3.3%-3.6%). With adding vitamins, the content of free fat in the samples decreased first and then increased. The color value L of all the samples decreased during storage. Compared with WMP, the color value B of all the infant formula powder with different ingredients decreased. Levels of 2-heptanone and 2-nonaone indicated that the formation of the main methyl ketones in the infant formula powder with different ingredients decreased. The content of hexanal in the sample added metal ions was the highest. The type and intensity of free radicals changed with the formula components. The range of g value was 2.0043-2.0060 after 6 months of storage and 2.0017-2.1338 after 12 months of storage, respectively. The index of peroxide value and color value B were significantly related to the existence of free radicals in the infant formula powder with different ingredients.

Preparation of molecularly imprinted hybrid monoliths for the selective detection of fluoroquinolones in infant formula powders.

A novel molecularly imprinted inorganic-organic hybrid monolith (MIP hybrid monolith) was fabricated through a facile single-step polymerization strategy with levofloxacin (LEV) as the template, 3-aminopropyltriethoxysilane-methacrylic acid as the hybrid functional monomer and ethylene glycol dimethacrylate as the crosslinker in a mixed porogen of methanol, toluene and dodecanol. The optimized LEV-MIP hybrid monolith was characterized using scanning electron microscopy and fourier transform-infrared spectroscopy. Uniform monolithic matrix with large through-pores in the network skeleton of LEV-MIP hybrid monolith was observed. The influence of polymerization conditions on the specific recognition behavior of the resulting monolith was systematically investigated. The LEV-MIP hybrid monolith exhibited much better adsorption (3.62 times) and selectivity towards LEV in comparison with non-imprinted hybrid monolith. Furthermore, the LEV-MIP hybrid monolith based solid-phase extraction combining with liquid chromatography-mass spectrometry was applied for the selective determination of fluoroquinolones (FQs) in infant formula powder. The average recoveries of six FQs in milk powders spiked at 20, 50 and 100 µg kg-1 were in the range of 82.91-102.00% with the precision of 1.04-7.39%. The limit of detection and limit of quantitation of the proposed method were in a range of 0.19-1.24 µg kg-1 and 0.63-4.13 µg kg-1, respectively.

Investigation on microbial contamination of infant formula powder during production process / 中国食品卫生杂志

Objective The aim of this study was to investigate the microbial contamination situation in infant formula powder during the processes of production.Methods A total of 880 samples were collected from Gansu Province,which included raw materials,manufacturing facilities,personnel swabs and final infant formula powder.The detection method conducted in this study were complied with the standard of the SN/T 0738-1997 and GB 4789,and the microbial species detected in this study included Enterobacteriaceae,Enterobacter sakazakii,and Bacillus cereus.Results The detection rate of Enterobacteriaceae was 28.41％ (250/880),the detection rates of Enterobacter sakazakii and Bacillus cereus were 0.46％ (4/872) and 16.94％ (31/183) respectively.The prevalence of Enterobacteriaceae (40.00％,40/100) was the highest in raw materials.Four Enterobacter sakazakii strains were isolated from the pretreatment workshop,equipment and environment surface.The prevalence of Bacillus cereus was 22.73％ (10/44) in final product.Conclusion The microbial contamination was existent widely in infant formula powder and the production procession.Rigid laws and managements should be conducted to reduce the microbial contamination in raw materials,production processes and the environment,which might improve the quality of infant formula powder.