Short term inhalation toxicity of a liquid aerosol of glutaraldehyde-coated CdS/Cd(OH)2 core shell quantum dots in rats.

Quantum dots exhibit extraordinary optical and mechanical properties, and the number of their applications is increasing. In order to investigate a possible effect of coating on the inhalation toxicity of previously tested non-coated CdS/Cd(OH)2 quantum dots and translocation of these very small particles from the lungs, rats were exposed to coated quantum dots or CdCl2 aerosol (since Cd(2+) was present as impurity), 6h/d for 5 consecutive days. Cd content was determined in organs and excreta after the end of exposure and three weeks thereafter. Toxicity was determined by examination of broncho-alveolar lavage fluid and microscopic evaluation of the entire respiratory tract. There was no evidence for translocation of particles from the respiratory tract. Evidence of a minimal inflammatory process was observed by examination of broncho-alveolar lavage fluid. Microscopically, minimal to mild epithelial alteration was seen in the larynx. The effects observed with coated quantum dots, non-coated quantum dots and CdCl2 were comparable, indicating that quantum dots elicited no significant effects beyond the toxicity of the Cd(2+) ion itself. Compared to other compounds with larger particle size tested at similarly low concentrations, quantum dots caused much less pronounced toxicological effects. Therefore, the present data show that small particle sizes with corresponding high surfaces are not the only factor triggering the toxic response or translocation.

Comparison of spot tests with AdultaCheck 6 and Intect 7 urine test strips for detecting the presence of adulterants in urine specimens.

BACKGROUND: Several adulterants are used to mask tests for abused drugs in urine. Adulterants such as "Klear" and "Whizzies" contain potassium nitrite while "Urine Luck" contains pyridinium chlorochromate (PCC). The presence of these adulterants cannot be detected by routine specimen integrity check (pH, specific gravity, creatinine and temperature). We previously reported the development of rapid spot tests to detect the presence of these adulterants. AdultaCheck 6 and Intect 7 urine test strips are commercially available for detecting the presence of these adulterants along with specific gravity, creatinine and pH in urine. METHODS: The performance of these two test strips for detecting adulterants was compared with the results obtained by spot tests. RESULTS: Both AdultaCheck 6 and Intect 7 effectively detected the presence of nitrite and pyridinium chlorochromate in urine. Moreover, both test strips successfully detected the presence of glutaraldehyde, for which no spot test is currently available. High amount of glucose and ascorbic acid did not cause any false positive result with AdultaCheck 6 or Intect 7. CONCLUSIONS: Both AdultaCheck 6 and Intect 7 can be used for checking the integrity of a urine specimen submitted for drugs of abuse testing.

The effect of glutaraldehyde adulteration of urine specimens on syva EMIT II drugs-of-abuse assays.

The effect of glutaraldehyde (the active component of "UrinAid") on Syva EMIT II drugs-of-abuse screening assays was studied. It was found that, dependent on the assay involved, concentrations of between 0.75 and 2.00% (v/v) of glutaraldehyde in urine could give rise to false-negative screening results. A simple method for identifying urine specimens that have been adulterated with glutaraldehyde, based on final absorbance rate readings (dA/min), is proposed.

Distribution, metabolism, and excretion of [14C] glutaraldehyde.

Radiolabeled glutaraldehyde (GA) was infused into rats in order to determine its distribution between cellular and humoral fractions of the blood, its potential metabolism by RBC's, its rate of excretion, and the nature of its urinary products. This study demonstrated that [14C]GA was distributed between the RBC's and plasma at a ratio greater than 1. Although the absolute counts of both fractions dropped 80% over 3 days, the percentage bound or incorporated increased over time. Despite the extensive uptake by RBC's these cells were unable to metabolize GA to CO2. Urinary excretion of the radiolabel was rapid; the predominant form in the urine was less than 1 kDa in size. All evidence suggested that it was not native GA. We conclude that the RBC's can incorporate GA, but can not metabolize it completely to CO2. Nevertheless, much of the infused GA was rapidly converted to nonreactive metabolites and eliminated by the kidney.