The Standard – June 2012

The Centers for Disease Control and Prevention has recently released an updated list of chemicals to its report on human exposure to Environmental chemicals. This update brings to 219 the number of chemicals identified in human blood or tissue, the most comprehensive analysis to date of human exposure. Click here to read the full CDC report.

In the interest of bringing more isotopically labeled standards to our customers, we are sometimes faced with standards that do not store well in the various solvents we use. One way to provide a known amount of standard that can be kept for more than a few weeks or months is to dry down a known volume of fresh solution for future reconstitution. Read more about the procedure and the standards we have available.

Recently, the United States Environmental Protection Agency decided to regulate perchlorate under the Safe Drinking Water Act. Recent research has shown perchlorate to have potential endocrine disrupting effects in humans, with possible effects on the thyroid. Given perchlorate levels in water, the EPA has determined that there is an opportunity for health risk due to perchlorate levels. 

Hydroxylated polyaromatic hydrocarbons have been PAH metabolites of interest for many years as biomarkers for asphalt production, coal smoke, and aerosols, as well as other uses. The presence of these compounds in human urine is an indication of exposure to PAHs from industrial sources, and the Centers for Disease Control and Prevention has been studying human exposure to PAHs from combustion for many years.