Weck Laboratories has received NELAP certification for a new Cyanide method in wastewater  matrices from the California Department of Public Health.  The new method, offers lower detection limits, and fewer interferences than in the routine EPA 335.4 method currently employed.  On April 17, 2012 the USEPA Administrator signed a Method Update Rule (MUR) approving new methods for analysis of NPDES wastewater samples. Six ASTM methods covering sampling, preservation and analysis of free, available and total cyanide are included in the MUR.  USEPA approval of ASTM D 7511-09e2 allows labs to analyze samples for total cyanide without a preliminary 2-hour acid distillation step. The instrument uses in-line UV digestion to dissociate metal-cyanide complexes and measure total cyanide in minutes.  Read more... 

Weck Laboratory was recently awarded a research contract for analysis of Nicotine and metabolites in biological fluids.  The three target analytes: Nicotine, Cotinine and t-3'-Hydroxycotinine are analyzed by direct injection liquid chromatography and electro-spray positive ionization mode tandem mass spectrometry.  The laboratory has demontrated direct injection reporting limits for each compound at 1 microgram per liter (ug/L) and method detection limits less than 0.3 ug/L.  Environmental water samples can be analyzed with reporting limits approximately 500 times lower limits [2 nanograms per liter (ng/L)] with concentration by solid phase extraction (SPE) technique.  Cotinine has been routinely analyzed since the beginning of 2009 with a suite of 38 hormones, pharmaceuticals and personal care products at the low parts per trillion levels (ng/L). 

Indicator parameters for monitoring the progress of natural attenuation of hydrocarbon contaminated sites includes the analysis for low molecular weight hydrocarbon gases released by microbial action as heavier hydrocarbons are broken down.  These are typically Methane, Ethane, Ethene & Propane.  These light hydrocarbons are monitored in groundwater samples by a static heated headspace procedure.  Water samples are heated in vials partially filled with the water sample.  Upon reaching equilibrium, the headspace vapor over the water is subsampled and injected into a gas chromatograph equipped with a flame ionization detector.  Upon separation of the components and combustion, the concentrations are determined from the proportional response of the charged combustion fragments to an electrical current in the detector.  The light hydrocarbons can be measured to low ppb levels in water samples. 

Cleaning validation for production equipment at pharmaceutical facilities is an evaluation that is conducted to prevent cross-contamination from previously processed products and detergent used for equipment cleaning, as well as foreign material from the environment that could be present in in the production equipment. The amount of Total Organic Carbon (TOC) found is compared with specific permissible limits to make sure they are not exceeded. Of the different techniques used to performed this task, the preferred method is the direct combustion of the swab and analysis by a TOC analyzer equipped with a solids combustion unit capable of accommodating the swabs. The instrument used for this test at Weck Labs is the latest generation Shimadzu TOC-LCPH with the SSM-5000A Swab combustion unit.  Read more....