Rates and types of urine drug screen false negative results compared with confirmatory toxicology testing in major trauma patients.

Background: Trauma centers are required to screen patients for alcohol use, and if necessary, intervene and refer to treatment (SBIRT). Similar screening for illicit drug use is recommended but not required. Urine drug screening (UDS) underestimates problematic substance use.

Aging shapes Cr(VI) speciation in five different soils.

To make sound decisions regarding management of heavy metal contamination in soils, it is necessary to understand contaminant transformations over extended periods. In this study, sequential extraction methods were applied to quantify the changes of Cr fractions [available Cr(VI), immobile Cr(VI) and immobile Cr(III)] in five contrasting soils spiked with Cr(VI) over a 240-day incubation. Results showed that available Cr(VI) in soils continually decreased during aging, with a sharp decline occurring in the first 30 days.

Failure of chelator-provoked urine testing results to predict heavy metal toxicity in a prospective cohort of patients referred for medical toxicology evaluation.

Introduction: Provoked urine testing (PUT), involving chelating agent administration prior to measuring urine metal excretion levels, is used by some alternative health care practitioners to diagnose patients with heavy metal poisoning. Multiple medical societies have advised against this practice due to its presumed unreliability, expense, and lack of validation. However, no prospective study of the predictive value of PUT for heavy metal poisoning has been undertaken.

Impact of pyrolysis temperature and activation on oily sludge-derived char for Pb(II) and Cd(II) removal from aqueous solution.

This study investigated the Pb(II) and Cd(II) sorption from aqueous solution by oily sludge-derived char (OSDC) prepared at different pyrolysis temperatures and chemical activation. The maximum Pb(II) sorption capacity for OSDC at pyrolysis temperature of 500 °C (OS500) was found as 351.48 mg/g, which was greater than that of OSDC produced at other temperatures.

Formation and Immobilization of Cr(VI) Species in Long-Term Tannery Waste Contaminated Soils.

Chromium speciation in naturally contaminated soils appears more complex than spiked studies have shown. This study characterized Cr speciation (oxidation states; availability; molecular geometry) intended to highlight the genesis of immobile Cr(VI) species in long-term tannery waste-contaminated soils. In a series of samples obtained from Shuitou in China, chemical extraction methods showed that Cr(III) was dominant(>96.