Tuba Humaira Rashid, Rana Sohel, Fariha Khandaker Atkia, Degen Gisela H, Ali Nurshad
Department of Biochemistry and Molecular Biology, Shahjalal University of Science and Technology, Sylhet 3114, Bangladesh.
Department of Veterinary and Animal Science, Rajshahi University, Rajshahi 6205, Bangladesh.
Toxins (Basel). 2025 Aug 8;17(8):399. doi: 10.3390/toxins17080399.
Breast milk is the ideal source of nutrition for infant growth and development. However, when nursing mothers consume aflatoxin B (AFB)-contaminated food, the hydroxylated form aflatoxin M (AFM) is transferred to breast milk and urine. AFB and its metabolite AFM are potent carcinogens and can pose significant risks to food safety and public health worldwide. This study determined the prevalence of AFM in the breast milk and urine of nursing mothers in Bangladesh and estimated infant exposure to this toxin. Breast milk and urine samples (72 each), collected from nursing mothers in three different regions of the country, were analyzed for AFM occurrence via a sensitive enzyme-linked immunosorbent assay (ELISA). AFM was present in 88.9% of urine samples, with a mean concentration of 109.9 ± 52.8 pg/mL, ranging from 40.0 to 223.8 pg/mL. AFM was also detected in 50% of the breast milk samples, with a mean concentration of 4.6 ± 0.7 pg/mL, ranging from 4.0 to 6.1 pg/mL. A strong correlation (r = 0.72) was observed between milk and urinary AFM levels, indicating these as suitable biomarkers of AFB exposure. Yet, no significant correlations were identified between AFM levels in either milk or urine and the food items typically consumed by nursing mothers. The average estimated daily intake (EDI) for AFM with breast milk was 0.59 ng/kg bw/day, with no significant difference between infants (0.57 ng/kg bw/day) and toddlers (0.65 ng/kg bw/day). A comparison of computed EDI ranges for AFM with a proposed tolerable daily intake value resulted in Hazard Indices below 1 for all exposure scenarios. This indicates that the AFM concentrations in breast milk from three regions of Bangladesh raise no concern. Also, the measured levels were far lower than the maximal levels set in the EU regulations for AFM in dairy milk and infant formula (50 ng/kg and 25 ng/kg, respectively).
母乳是婴儿生长发育的理想营养来源。然而，当哺乳期母亲食用受黄曲霉毒素B（AFB）污染的食物时，其羟基化形式的黄曲霉毒素M（AFM）会转移到母乳和尿液中。AFB及其代谢产物AFM是强效致癌物，会对全球食品安全和公众健康构成重大风险。本研究测定了孟加拉国哺乳期母亲母乳和尿液中AFM的流行情况，并估算了婴儿对这种毒素的暴露量。通过灵敏的酶联免疫吸附测定法（ELISA），对从该国三个不同地区的哺乳期母亲收集的母乳和尿液样本（各72份）进行了AFM检测。88.9%的尿液样本中存在AFM，平均浓度为109.9±52.8 pg/mL，范围在40.0至223.8 pg/mL之间。50%的母乳样本中也检测到了AFM，平均浓度为4.6±0.7 pg/mL，范围在4.0至6.1 pg/mL之间。母乳和尿液中的AFM水平之间存在很强的相关性（r = 0.72），表明它们是AFB暴露的合适生物标志物。然而，在母乳或尿液中的AFM水平与哺乳期母亲通常食用的食物之间未发现显著相关性。通过母乳摄入AFM的平均估计每日摄入量（EDI）为0.59 ng/kg体重/天，婴儿（0.57 ng/kg体重/天）和幼儿（0.65 ng/kg体重/天）之间无显著差异。将计算出的AFM的EDI范围与提议的每日可耐受摄入量值进行比较，结果显示所有暴露情况下的危害指数均低于1。这表明孟加拉国三个地区母乳中的AFM浓度无需担忧。此外，所测水平远低于欧盟法规对牛奶和婴儿配方奶粉中AFM设定的最高水平（分别为50 ng/kg和25 ng/kg）。
