West African children exposed through their diet to a common mold toxin have impaired growth, according to a study published in the September 2004 issue of the journal Environmental Health Perspectives (EHP). The study of 200 children, who were 16-37 months of age when the study began in February 2001, found a strong correlation between aflatoxin exposure and growth over the eight-month study period.
The high heat and humidity of many tropical developing countries, combined with poor storage conditions, allows for mold growth in harvested crops like maize or groundnuts (such as peanuts). In fact, exposure to aflatoxin was nearly ubiquitous in the children each time they were studied.
Researchers analyzed 50 children in each of four villages in the West African nation of Benin. Two of the villages had higher aflatoxin growth, and two villages had lower levels. Blood samples from the children were analyzed three times for levels of aflatoxin-albumin, a biomarker of recent aflatoxin exposure. Vitamin A and zinc levels were also analyzed, and children and their mothers were weighed and measured at each survey point.
Children with the highest levels of the aflatoxin biomarker grew an average 1.7 centimeters less than those with the lowest levels. Poor nutrition did not appear to be a factor in the reduced growth. Researchers noted that the strong correlation could have been even more stark if the growth of the children studied were compared with the growth in children in developed countries.
All the levels of aflatoxin exposure in this study are high and chronic in nature compared with developed countries. If the effects on growth were compared with children infrequently exposed to negligible toxin levels, the observations may appear even more striking, the study authors write. The strong association between aflatoxin exposure and impaired growth may have significant effects on other aspects of children health, such as immunity and susceptibility to infectious diseases.
The researchers theorize that aflatoxin could conceivably affect growth by altering mucosal barriers and lowering resistance to intestinal infection. The group is now conducting research to test that theory.
The safety of the food supply is among the most important and most basic public health concerns, said Dr. Jim Burkhart, science editor for EHP. We can see from this study a very real impact on these children from aflatoxin exposure. To the extent that intervention measures can reduce exposure to this mold toxin, the benefits could be significant.
The lead author of the study was Yunyun Gong of the School of Medicine at the University of Leeds. Other authors were Assomption Hounsa, Sharif Egal, Paul C. Turner, Anne E. Sutcliffe, Andrew J. Hall, Kitty Cardwell, and Christopher P. Wild.
Source: Environmental Health Perspectives