NONANALYTIC PROBLEMS IN DETECTING ARSENIC AND CADMIUM IN CHILDREN LIVING NEAR A CADMIUM REFINERY IN DENVER, COLORADO

The aim of the present study was to determine urinary arsenic (N = 322 ) and cadmium (N = 366) levels in children aged six months to six year s who live near a working cadmium refinery and to compare their values with those of children from comparison neighborhoods. A questionnaire designed to identify exposure pathways was administered to the parent s. There were unexpected problems in the study. Eighty-four percent of the arsenic samples were below the detection limit of 10 ug/l and sum mary statistics could not be calculated. Urinary arsenic and cadmium v alues could not be standardized for volume and concentration of urine because a large proportion of the samples had very low creatinine valu es. The original round of cadmium testing was afflicted with contamina tion problems, possibly due to the mishandling of pediatric urine bags by the parents during the collection procedure. A retest for cadmium levels under clinical conditions showed lower cadmium levels, all but two were below the detection limit. While biological monitoring of exp osure to metals can be undertaken indirectly by measuring the concentr ation of the metals in urine, the analyses in this study were complica ted by (1) nol using more sensitive analytical tests for arsenic and c admium determination, (2) not being able to standardize children's uri nary values with creatinine, and (3) allowing in-home urine collection .