Low level aflatoxin exposure associated with greater linear growth in southern Mexico: A longitudinal study

Abstract

Aflatoxins are a group of naturally occurring mycotoxins, which can lead to death and are a known cause of hepatocellular carcinoma. AF exposure has been hypothesised to lead to stunted growth in children, but separating the AF effect from other determinants of linear growth retardation is difficult. The study used secondary data from an efficacy trial conducted in young children in southern Mexico to test the comparative efficacy of a milk-based multiple micronutrient-fortified food, a multiple micronutrient syrup, or a multiple micronutrient powder. The effect of serum AFB -lysine adduct level on incremental growth was tested using a longitudinal mixed model, controlling for key individual, maternal, and household-level covariates. AFB -lysine adduct was detectable in all but 2 of the 347 children in the study (median exposure: 0.82 pg/mg albumin). AF exposure was associated (p < .05) with greater linear growth: an increase equivalent to the sample interquartile range (~0.5 pg AFB -lysine/mg albumin) was associated (p < .05) with an increase in the child's height-for-age deficit of 1.5 to 2.0 mm in the 4 months from baseline (average age 8 months) to follow-up (average age 12 months); the magnitude of the difference in the 10-month follow-up was smaller and not statistically significant. This study documents that low-dose AF exposure was associated with greater child linear growth. Given its toxicity and carcinogenicity, our results do not change the urgent need to drastically reduce human AF exposure. Our findings show that the association between AF exposure and linear growth is more complex than previously thought.

Human Biomonitoring of Mycotoxins in Blood, Plasma and Serum in Recent Years: A Review

“…However, sample preparation for this technique is time-consuming [70]. Liquid chromatography coupled with fluorescence detection (LC-FLD) was used frequently (24% of the methods reviewed) [54,55,57,58,81,[85][86][87][88][89][90][91][92].…”

“…To release AFB1-lysine (AFB1-lys) adduct from albumin, proteins in serum samples are digested with Pronase ® for a few hours at 37 • C. AFB1-lys is then extracted and purified with SPE by means of a mixed-mode anion exchange reversed-phase matrix. Next, the analytes are eluted, mainly through the use of methanol (MeOH) with formic acid, then concentrated and reconstituted in the mobile phase before analysis with LC-MS/MS [49,65,81,83,87,[112][113][114][115], LC-FLD [81,[88][89][90][91][92] or ELISA [73][74][75][76][77][78][79]117]. McCoy et al (2008) [70] and Scholl et al (2006) [123] reported good correlations of the concentration levels obtained from ELISA, LC-FLD and LC-MS.…”

“…A number of studies have been carried out to evaluate the presence of AFs in plasma or serum from children with severe acute malnutrition (SAM) in Kenya [92], Nigeria [49], Tanzania [113,117] Uganda [88,90], Mexico [81,91] and other countries [75,[77][78][79]83,87,114,115]. This is a particularly relevant topic due to the rates of childhood growth disorders in these countries.…”

Present Status and Perspective on the Future Use of Aflatoxin Biocontrol Products

“…Therefore, in emerging and developing nations, most contaminated crops enter the food and feed chains, regardless of their aflatoxin content [3,[20][21][22][23][24][25]. The absence of mechanisms to enforce aflatoxin tolerance levels results in chronic aflatoxin exposure with subsequent lack of access to markets, poverty, low well-being, poor economic growth, being among other constraints in the affected populations [2,26,27]. For all these reasons, in the developing world, contamination of food and feeds with aflatoxins has a profound negative impact on personal, social, and national development opportunities.…”

Aflatoxin exposure in utero and birth and growth outcomes in Tanzania

“…These results suggest that low levels of aflatoxin may not contribute to growth impairment in this sample, though fumonisin may play a role (Chen et al, ). Leroy et al found that low‐level aflatoxin exposure (median level = 0.82 pg/mg) was actually associated with greater linear growth in a longitudinal study of infants in southern Mexico (Leroy, Sununtnasuk, García‐Guerra, & Wang, ). Lastly, a recent study using a maternal and newborn cohort in Nepal found that relatively low maternal aflatoxin exposure was associated with a slight increased risk of being small for gestational age but not with birth weight, birth length, anthropometric z‐scores, low birthweight, stunting, or preterm birth (Andrews‐Trevino et al, ).…”