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How to Select and Use a Particle Counter (149)

August 7, 2009

There are many types of particle counters dependent upon the depth of particle analysis required: To measure ultrafine particles (size in nanometer range) one may utilize a condensation nucleus particle counter. Ultrafine airborne particle smaller than 0.1µm (micron), which generally cannot be detected by ordinary …

Dust: A Metric for Use in Residential and Building Exposure Assessment and Source Characterization (151)

July 28, 2009

Abstract In this review, we examine house dust and residential soil and their use for identifying sources and quantifying levels of toxicants for the estimation of exposure. We answer critical questions that focus on the selection of samples or sampling strategies for collection and discuss …

CDC

Why are Bacteria Becoming Resistant to Antibiotics? (152)

July 23, 2009

Antibiotics kill or inhibit the growth of susceptible bacteria. Sometimes one of the bacteria survives because it has the ability to neutralize or evade the effect of the antibiotic; that one bacteria can then multiply and replace all the bacteria that were killed off. Exposure …

Sorting Out Green Advertising Claims (159)

July 21, 2009

Grocery shelves, hardware stores, card shops, and other retail operations are filled with products and packages announcing environmental features that may influence your purchasing decisions. But when it comes to products and packaging, what do claims like “environmentally safe,” “recyclable,” “degradable” or “ozone friendly” really …

EPA

Why Green Your Cleaning Products? (156)

July 21, 2009

The following discussion primarily addresses hazards associated with cleaning product ingredients. The actual risks from these chemicals at typical exposure levels are often uncertain, and in many cases are probably low. Regardless of the expected risk levels, however, reducing the intrinsic hazard of a product …

Bringing Home Something Other than Homework from School: Microbial Contamination from Highly Touched Objects (154)

July 21, 2009

Increasing quantitative evidence points to the conclusion that children  are more susceptible to infection by microbial pathogens picked up from their environments than older persons exposed to the same pathogens [1]. There are many causes that underlie this increased risk but probably the major one …