Changes in hair arsenic levels in breast and bottle fed infants during the first year of infancy.

Hair samples were collected from 13 breast fed and 19 bottle fed infants at one, three, six and twelve months of age. Food frequency data were also collected. Arsenic and antimony concentrations determined in washed hair samples by neutron activation procedures, rose significantly with age, the highest levels being evident at twelve months. Hair arsenic and antimony levels were independent of sex, and method of milk feeding. However, at twelve months, the median hair arsenic level for those infants receiving cereal at six months of age (0.655 microgram/g) was significantly higher (p = 0.05) than for those infants fed exclusively a milk based diet at this time (median = 0.225 microgram/g). Recent data show that cereals are major dietary sources of arsenic during infancy. Hence findings of this study suggest that changes in hair arsenic levels during infancy are related to the introduction of cereals in the diet.