PH03 Perchlorate
Exhibit Hall
8:00 AM - Thursday, 13 November 2003
(PH055) Acute Exposure to Ammonium Perchlorate in Quails.
Gentles, Angella1, Smith, Ernest 1, Surles, James 2, Perlmutter, Lisa1, Williams, Lancelot1, Ramachandran, Bharath1, 1 The Institute of Environmental and Human Health, Texas Tech University, Lubbock, TX, USA2 Mathematics, Texas Tech University, Lubbock, TX, USA
ABSTRACT- Perchlorate (AP), a common groundwater contaminant, inhibits production of thyroid hormones by displacing iodine and has been shown to affect wildlife. In this study, AP was administered to quail at concentrations of 0mM (0 ppm), 0.01 mM (1.17 ppm), 0.1 mM (11.75 ppm), and 1mM (117.49 ppm) in drinking water. The following endpoints were evaluated: accumulation of AP in egg and liver, organ weights, plasma thyroid hormone levels and thyroid histology. Exposure to 0.01 mM AP exposure resulted in detection of perchlorate in quail eggs ranging from 0 to 58 ng/g with average was 21.3 ng/g. At 0.1 mM, perchlorate detection in quail eggs ranged from 11 to 236 ng/gm, while at 1 mM the range was 1165 to 3415 ng/g with an average of 50 and 1802 ng/g, respectively. In the liver, exposure to 0.01mM AP resulted in perchlorate detection ranging from 0 to 294 ng/g liver dry weight, while at 1 mM perchlorate ranged from 0 to 878 ng/g liver dry weight. Analysis of organ weight revealed a borderline difference in the mean kidney weight (p = 0.053). The mean kidney weight for the control group was 1.61 and 1.89 for mM group. Statistical analysis of thyroid hormones indicated significant difference (p = 0.01) for mean plasma T4 concentration between the 0.1 and the 0.01 mM groups. The mean values for T4 were 21.29 pmol/L for control, 30.66 pmol/L for 0.01mM and 16.35 pmol/L for 0.1 mM. Histological evaluation indicated that quails exposed to 1mM of AP showed hyperplasic regions in various sections of the thyroid gland. No evidence of hyperplasia was observed in any section from the control thyroid glands. The data from this study indicate that AP affect the thyroid gland and can be transferred to quail eggs. Additional studies are required to further characterize chronic exposure of adults.
Key words: Bird, Ammonium Perchlorate, Thyroid gland, thyroid hormone