Perchlorate (ClO4) release into the environment has occurred primarily in association with its manufacture and use in solid rocket propellant. When released into groundwater, perchlorate can spread over large distances because it is highly soluble in water and adsorbs poorly to soil. Two proven techniques to remove perchlorate from drinking water are anaerobic biological reactors and ion exchan...

Anaerobic bioreactors have been developed to remove perchlorate from water, but backwashing and operational interruptions can expose biofilms to oxygen. While it is well known that oxygen is a preferential electron acceptor to perchlorate for perchlorate-respiring bacteria, little is known about the effect of oxygen exposure or redox potentials on perchlorate reduction. Four different dissolved...

Thyroid storm represents the extreme manifestation of thyrotoxicosis as a true endocrine emergency. Although Grave's disease is the most common underlying disorder in thyroid storm, there is usually a precipitating event or condition that transform the patient into life-threatening thyrotoxicosis. Treatment of thyroid storm involves decreasing new hormone synthesis, inhibiting the release of th...

Spin-coated films, approximately 100 nm thick, of a newly synthesized bis[octakis(octyl)phthalocyaninato] lutetium(III) complex on ultrasonically cleaned glass substrates exhibit pronounced chemichromic behaviour with potential application in healthcare. In situ kinetic optical absorption spectroscopic measurements show that the phthalocyanine Q-band is red shifted by 60 nm upon oxidation arisi...

Perchlorate, an iodide uptake inhibitor, is increasingly being detected in new places and new matrices. Perchlorate contamination has been attributed largelyto the manufacture and use of ammonium perchlorate (the oxidizer in solid fuel rockets) and/or the earlier use of Chilean nitrate as fertilizer (approximately 0.1% perchlorate). However, there are regions such as the southern high plains (T...

The effect of nitrate, acetate, and hydrogen on native perchlorate-reducing bacteria (PRB) was examined by conducting microcosm tests using vadose soil collected from a perchlorate-contaminated site. The rate of perchlorate reduction was enhanced by hydrogen amendment and inhibited by acetate amendment, compared with unamendment. Nitrate was reduced before perchlorate in all amendments. In hydr...

Removal of perchlorate using either acid-washed zero-valent aluminum or aluminum hydroxide was studied in batch reactors under ambient temperature and pressure. Approximately 90-95% of perchlorate was removed within 24h in the presence of 35 g L(-1) aluminum at acidic pH (4.5+/-0.2). Although aluminum is a strong reductant, this study indicated no explicit evidence to support perchlorate reduct...

There have been increasing human health and ecological concerns about ionic perchlorate (ClO4-) since it was detected in drinking water sources in 1997. Perchlorate is known to affect thyroid function, causing subsequent hormone disruption and potential perturbations of metabolic activities. According to current estimates, perchlorate is found in the surface of groundwater of 14 states, includi...

In the past few years, it has become increasingly apparent that perchlorate (ClO(4)(-)) is present on all continents, except the polar regions where it had not yet been assessed, and that it may have a significant natural source. Here, we report on the discovery of perchlorate in soil and ice from several Antarctic Dry Valleys (ADVs) where concentrations reach up to 1100 microg/kg. In the dries...

Perchlorate is known to competitively interfere with iodide uptake by the thyroid gland and thereby human exposure to perchlorate is a public health concern. Prevalence of perchlorate in dairy milk is documented; nevertheless, co-occurrence of perchlorate with other thyroid-binding monovalent ions such as iodide and nitrate is not well understood. In this study, we analyzed perchlorate, iodide,...