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Posts Tagged ‘Methods’

Qualitative Aspects of Environmental Testing for Organic Parameters – An Overlooked Facet of Data Quality

Monday, May 27th, 2013

By Lee Wolf, Regulatory Affairs Manager, ALS Environmental – USA

One may look at classical wet chemistry and the pioneering chemists and wonder. What were they really doing? What were they looking for? Discovering tests for isolating and identifying chemical components was the purpose. One cannot envision that accuracy and precision, or detection limits were of much concern. Fast-forward to the infancy of environmental testing and one can still find the identification of chemical components of utmost importance in developing methods and technology.

Currently, and for recent years, the focus of environmental measurements has predominately been on quantitative aspects. Significant emphasis is now put on detection limits, quantitation limits, accuracy and precision, and uncertainty of measurements. That is, an emphasis on sensitivity over selectivity, both in terms of data quality and data usability. Yet fundamentally, the targeted component(s) of a sample must first be accurately identified before accurate quantitation can occur.

In this paper, the shift in focus from selectivity to sensitivity in the analysis of organic compounds will be discussed and potentially overlooked qualitative data quality considerations examined. Examples of the reliance on standard methodologies and how they can lead to qualitative errors is examined, and how the need for a strong understanding of method selectivity and the use of qualitative tools is important.

Read more about Qualitative Aspects of Environmental Testing…

How to Determine Aquatic Humic Substances

Monday, June 28th, 2010

By Lynda Huckestein, Project Chemist, Kelso, WA

How to Determine Aquatic Humic Substances

Aquatic Humic Substances (AHS) result from the decomposition of plant and animal residues and are found in soil, sediment, and water. They are widespread in nature and are mostly comprised from naturally occurring dissolved organic matter in water.

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Update to Massachusetts Air Petroleum Hydrocarbons (APH) Method

Thursday, April 16th, 2009

MassDEP APH MethodThe Massachusetts Department of Environmental Protection (MassDEP) recently updated and finalized their Air-Phase Petroleum Hydrocarbons (APH) analytical method. The APH method, which had been in draft format since February 2000, was completed last year by a MassDEP Workgroup and approved after a month long public comment period in December 2008. The committee was comprised of MassDEP personnel, laboratory experts and data users.

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