Effects of Perchlorate

Perchlorate (C104 ) was used in explosives, propellants, and pyrotechnics in the forms of ammonium, sodium, and potassium perchlorate. Although perchlorate can persist as a contaminant in ground and surface water, assessment of the perchlorate toxicity to soil invertebrates received little attention due to its high aqueous solubility and mobility, which diminish potential exposure of soil organisms. Limited soil invertebrate toxicity data for sodium perchlorate was determined in studies with E. fetida exposed in sand/manure mixture (20 4 weight/weight) or artificial soil (filter paper 

Specific mechanisms of changes in the toxicity following weathering and aging of EMs in soil are not well understood. Compounds produced due to TNT degradation 

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In contrast to these results, Stanley and Shorter207 found the catalytic effect of perchloric acid to be large in 40 % aqueous acetic acid, the difference in behaviour from 75 % acid being attributed to the presence of a much higher concentration of hypochlorous acid in the more aqueous medium. 

The catalytic effect of perchloric acid has already been explained436, and the anticatalytic effect of water follows from the equilibrium constant of 34 for equilibrium (215)... 

Braverman LE, He X, Pino S, Cross M, Magnani B, Lamm SH, Kruse MB, Engel A, Crump KS, Gibbs JP (2005) The effect of perchlorate, thiocyanate, and nitrate on thyroid function in workers exposed to perchlorate long-term. J Clin Endocrinol Metab 90 700-706... 

The effect of perchlorate ions on cadmium electrodeposition was investigated in water-AN mixtures [227, 228]. The formation of ionic associates in the surface layer inhibited cadmium electrodeposition, and promoted the formation of higher quality coatings. 

As more information on the extent of the contamination and the dangerous effects of perchlorate consumption has become available, much concern has arisen over perchlorate contamination in public water systems. Furthermore, the US Environmental Protection Agency (USEPA) has periodically reduced the acceptable limit for safe consumption. Currently, the limit stands at 0.7 pg/kg/day, which corresponds to 24.5 pg/E for a 70 kg human drinking 2 E of water per day. The method described by Eamb et al. [17] provides effective perchlorate determinations (shown in Figure 7) using standard conductimetric detection by combining an... 

TABLE VIII. Effect of perchloric acid treatment on the of Cr, Mo and Pd analyses... 

TABLE X. Effect of perchloric acid on the analysis of chromium... 

To determine the instrumental response as a function only of the background matrix of the solution, the effect of perchloric acid on Cr, Mo, and Pd was tested independently of the digestion procedure. The variables were (1) presence of filter matrix in solution (2) presence of perchloric acid (3) presence of lanthanum flame buffer in solution and (4) concentration. The data are presented in Table XI. Slightly high recoveries (4 to 9 percent) were obtained for Cr when the filter matrix was present in solution. Recoveries of approximately 120 percent were obtained from the 1.0 ug/ml samples containing perchloric acid. This was found to be caused by Cr contamination in the perchloric acid. The corrected analytical results showed that the presence of either perchloric acid or lanthanum in solution has essentially no effect on the instrumental response for Cr in a lean air-acetylene flame. 

An optical study s of Ce(III) indicated the existence of a complex, CeC104 ". The formation constant was evaluated as about 80 at zero ionic strength and was found to decrease rapidly with increasing ionic strength, in accordance with the Debye-Huckel theory. If this interpretation is correct, it would seem that Ce(IV) must also form a perchlorate complex of comparable stability to account for the lack of effect of perchlorate on the potential. 

The effect of perchloric acid concentration on the qucmtum yield of the photoinduced O exchange between and H O has... 

Landrum M et al., Effects of perchlorate on earthworm (Eisenia fetida) survival and reproductive success, Sci. Total Environ., 363, 237, 2006. 

Welch MJ, Adatepe M, Potchen EJ (1969) An analysis of technetium ( " TcOlJ) kinetics the effect of perchlorate and iodide pretreatment. Int J Appl Radiat Isot 20 437-445 Wolff J, Maurey JR (1962) Thyroid iodide transport. III. Comparison of iodide with anions of periodic group VIIA. Biochim Biophys Acta 57 422-426... 

Figure 26.1 Effect of perchlorate (KCIO4 ) on 26 - and uptake. Rats were i.p. injected with KCiO (20mg/kg) 2h iater 50. rCi of either 25 - or was injected, and the animals were sacrificed 1.0h after the radioactivity administration. Data were normalized as radioactivity uptake (cpm) compared to liver (nonuptake organ) and expressed as cpm tissue/cpm liver. Thyroids were obtained from female and male rats. Results are expressed as the mean SD, n = 7 rats/group. Data were analyzed with one-way ANOVA, and differences between means were evaluated by the Tuckey test. Different letters indicate significant differences between groups (p < 0.05).

Several clinical studies have not reported any adverse effects of perchlorate on thyroid function in newborns, pregnant women, and nonpregnant adults (Li et al., 2000 Tellez et ai, 2005 Amitai et al., 2007). The one study that... 

Since it has been suggested that the fetus and infant might be more susceptible to the adverse effects of perchlorate on neonatal thyroid function, the perchlorate content of breast milk and infant formulae was assessed. We found that perchlorate was detected in all 49 breast milk samples (median, 9.1pg/l) and in 17 infant formulae (median, 1.5pg/l). There was no correlation between breast milk perchlorate and breast milk iodine content, even in those 27 samples with perchlorate concentrations greater than lOpg/1 (Pearce et al., 2007 b). This is in contrast to the data reported by Kirk et al. (2005) in 6 breast milk samples in which there was a negative correlation between perchlorate and iodine content. Perchlorate has also been detected in cows milk in the US (5.9 1.8 o,g/l) (Kirk et al., 2005) and in Japan (9.4 2.7 J,g/l) (Dyke et al., 2007). 

It is obvious that drinking water is not the only source of perchlorate in the US, and probably worldwide, and that perchlorate appears to be ubiquitous in the environment. Thus, it is difficult to reconcile the presence of perchlorate in drinking water alone as a potential health hazard, and it appears unlikely that the potential adverse effects of perchlorate on the thyroid pose a risk to the general population. 

In nude mice transplanted with autonomous adenoma tissue the efficacy of a prophylaxis with perchlorate and methimazole has been demonstrated. This effect of perchlorate and methimazole could only be observed in mice treated before excessive iodine-load. Antithyroid... 

Wachter W, Buchner R, Hefter G (2006) Hydration of tetraphenylphosphonium and tetraphenylb-orate ions by dielectric relaxation spectroscopy. J Phys Chem B 110 5147-5154 Wachter W, Fernandez S, Buchner R, Hefter G (2007) J Phys Chem B 111 9010-9017 Walrafen GE (1970) Raman spectral studies of the effects of perchlorate ion on water structure. J Chem Phys 52 4176-4198... 

Diazonium ions, scrambling 612 Diazotization, by alkyl nitrites 317 by nitrosyl halides 309 by nitrous anhydride 307, 317 effect of perchloric acid on rate 311, 312, 315-317... 

With very basic amines, the catalytic effect of perchloric acid is much stronger than that for j -nitroaniline. For example,... 

Ammonium perchlorate (AP) has apphcations in munitions, primarily as an oxidizer for solid rocket and missile propellants. It is also used as an air-bag inflator in the automotive industry, in fireworks, and is a contaminant in agricultural fertilizers. Because of these uses and ammonium perchlorate s high solubility, chemical stability, and persistence, it has become distributed widely in surface and ground water systems. There is little information about the effects of perchlorate in these systems or on the aquatic life that inhabits them. However, it is known that perchlorate is an endocrine disrupting chemical that interferes with normal thyroid function and that thyroid dysfunction impacts both growth and development in vertebrates. Because perchlorate competes for iodine binding sites in the thyroid, the addition of iodine to culture water has been examined in order to determine if... 

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