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Posts Tagged ‘ppb’

Polycyclic Aromatic Hydrocarbons (PAH) in Shellfish

Friday, May 28th, 2010

Polycyclic Aromatic Hydrocarbons (PAH) in Shellfish


Columbia Analytical Services, Inc. has extensive experience testing for low levels of Polycyclic Aromatic Hydrocarbons (PAH) in shellfish. Sensitive and selective techniques were developed over ten years ago and have been refined and improved on a continuing basis. In addition to the analysis for the common parent compounds, levels of the associated alkylated homologs can also be determined.

This analysis is typically performed using Gas Chromatography/Mass Spectrometry (GC/MS) operated in the Selective Ion Monitoring (SIM) mode. Key to the analytical procedure is proper sample preparation, which begins with shucking, compositing (as appropriate to the project plan), and homogenization via mechanical mixing. The preliminary preparation must be performed under clean laboratory conditions to prevent common PAH contamination. Decontamination of sample preparation equipment is performed and monitored closely to assure clean conditions. The sample homogenate is a homogenous slurry when prepared correctly. The homogenization techniques performed by Columbia Analytical have been inspected and approved by various organizations (e.g. US EPA, other federal government and state regulatory agencies, private industries, consultants, etc.) The data results for these projects were subjected to thorough government, public and private scrutiny.

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Nitrogen Dioxide Standard Released by EPA

Monday, April 19th, 2010

Nitrogen-Dioxide-Public-Health EPA released a new National Ambient Air Quality Standard (NAAQS) for nitrogen dioxide (NO2) in January. This new one-hour standard is aimed to protect public health from peak short-term exposures, especially along busy city streets and highways where NO2 exposure is the most likely. According to the EPA, NO2 exposure has been linked to impaired lung function and increased respiratory infections, especially in people with asthma.

NO2 is one of a group of highly reactive gasses. It forms quickly from emissions from cars, trucks, buses, power plants, and off-road equipment. In addition, NO2 contributes to the development of ground-level ozone and fine particle pollution.

Read more about the nitrogen dioxide standard…