Bromide residues in tissues from rats maintained on diets fumigated with methyl bromide
The effect(s) of bromide residues in rat diets on tissue bromide accumulations, organ size, growth rate and physical activity were studied. In Experiment 1, the treatment groups were fed diets containing 290, 600 and 1177 ppm bromide, respectively. The control group received 36 ppm from untreated feed. There were 12 rats on each diet for 56 days. Experiment 2 was divided into 4 groups of 5 rats each, and were fed a diet containing 1177 ppm bromide. Five representative animals were sacrificed every 2 weeks.
Weights of the liver, spleen, lungs, heart and testes were recorded for all animals when sacrificed. Tissue samples from these organs and the triceps, gastrocnemius muscle, eyes, abdominal fat, blood and tibia were analyzed by neutron activation analysis (NAA) for bromide residues. A computer program was designed to convert the NAA data to ppm bromide. There was a significant difference in the levels of bromide in the tissues between all treatments in both experiments. The most notable results were the high residual bromide levels found in the eyes (856 ppm) and testes (610 ppm). Bromides were detected in the other tissues in the following levels as ppm: blood (631), liver (304), kidneys (610), tibia (343), spleen (541), triceps (178), gastrocnemius (179), lungs (648), abdominal fat (99) and heart (359).
No significant differences in organ sizes, feed efficiency and rate of gain between animals in Experiment 1 or 2 were found.