Dietary cyanide from insufficiently processed cassava and growth retardation in children in the Democratic Republic of Congo (formerly Zaire)

Dietary cyanide exposure from cyanogenic glucosides in insufficiently proce ssed cassava has been advanced as a contributing factor in child growth ret ardation. Whether cyanide exposure aggravates children's growth retardation was studied by comparing two populations of children from the northern and the southern zones of the Bandundu region, Democratic Republic of Congo (f ormer Zaire), using dietary interviews, anthropometry and urine analyses. B oth populations consumed cassava as their staple diet, but whereas in the n orth the cassava was well processed, in the south it was inadequately proce ssed. The mean urinary thiocyanate was much higher in the south, whereas me an urinary sulphate excretion was equally low in the two areas. However, th e mean urinary SCN/SO4 molar ratio was higher in the south (0.20), indicati ng that 10-20% of sulphur amino-acids were used for cyanide detoxication. N o significant differences were found between the two populations in weight- for-height and weight-for-age indices but the height-for-age index was sign ificantly lower in children from the south, indicating more severe growth r etardation in children exposed to dietary cyanide. Because of the preferent ial use of sulphur amino-acids for cyanide detoxification in the human body , dietary cyanide exposure from cassava may be a factor aggravating growth retardation in Bandundu.