We thought it might be helpful for those of you with questions regarding EPA Method 245.7 to create a blog post addressing some of these questions. If you have any questions regarding EPA 245.7 that we haven't addressed here, please let us know and we will do our best to provide you with the answer.Read More
Teledyne Leeman Labs Blog
A new paper by researchers from the Woods Hole Oceanographic Institution (WHOI), Wright State University, Observatoire Midi-Pyréneés in France, and the Royal Netherlands Institute for Sea Research found that the ocean contains about “60,000 to 80,000 tons of pollution mercury. In addition, they found that ocean waters shallower than about 100 m (300 feet) have tripled in mercury concentration since the Industrial Revolution and that the ocean as a whole has shown an increase of roughly 10 percent over pre-industrial mercury levels.”[i] The paper, which appears in a recent addition of the journal of Nature “provides the first direct calculation of mercury in the global ocean from pollution based on data from 12 sampling cruises over the past 8 years,” and “a look at the global distribution of mercury in the marine environment.”
While mercury is a naturally occurring element, it is also a by-product of human mining and manufacturing operations, from burning coal to making cement. The researchers set out to better understand how much of the mercury in the ocean is a result of human activity or how much is from natural sources. The group looked at data about oceanic levels of phosphate, and by “determining the ratio of phosphate to mercury in water deeper than 1,000 meters (3,300 feet) that has not been in contact with Earth's atmosphere since the Industrial Revolution, the group was able to estimate mercury in the ocean that originated from natural sources such as the breakdown, or ‘weathering,’ of rocks on land.”Read More
Tags: mercury analysis
One week after a tailings pond dam burst at Mount Polley Mine near the cities of Williams Lake and Quesnel, British Columbia, environmental experts are saying it could be one of the worst tailings pond breaches in the world. Early estimates suggest that more than 2.64 billion gallons of mining waste and 4.5 million cubic meters of ground-up rock were released into Polley Lake, Quesnel Lake, Hazeltine Creek and Cariboo Creek. According to the mine’s owners 2013 mine report, substances that are disposed of on-site into the pond include arsenic, copper, lead, manganese, mercury, phosphorus, and selenium; among several other metals. Days following the breach, hundreds of local residents were banned from using the water for drinking or bathing, campgrounds were evacuated, fishing was banned and an emergency was declared.
As a company, we were saddened to read about the breach and by its initial and impending impact. Our first thoughts are with the people and communities in British Columbia who are suffering through this unfortunate situation. This type of disaster can have a devastating impact on the local ecosystem, and its clear that a massive waste removal project will be required in the future. Many are comparing this to a tailings pond breach in Tennessee in 2008, where cleanup was slow and estimated at $600-800 million. Monitoring the rise in toxins absorbed by fish and wildlife has started, and officials are conducting regular water quality tests of area resources to better understand the aftermaths. On a positive note, an early round of tests completed last week found that water “samples indicate that none of the chemical and physical parameter concentrations exceeded B.C. or Health Canada drinking water guidelines.” Unfortunately, “All five testing sites also had zinc levels above chronic, or long-term, exposure limits for aquatic life.”Read More
Tungsten Carbide (also called cemented carbide or simply carbide) is a metal composite created from tungsten carbide and a binder metal (usually cobalt or nickel) in powder form that is compacted and sintered in a furnace. Tungsten Carbide is used for tools, abrasives, jewelry, industrial drills, and armor-piercing ammunition due to its exceptional hardness (8.5-9.0, surpassed only by diamonds). Because the tungsten carbide particles are captured in a binder during the sintering process, the result is referred to as “cemented”.
Modern copper ores contain less than 0.6% copper, and less than 2% total volume of economic ore minerals (including copper). A majority of the ore is comprised of unwanted rock and gangue minerals (typically silicate minerals or oxide minerals). Separation of ore minerals from gangue minerals entails complicated and labor intensive processes.
When it comes to mercury analysis using Atomic Fluorescence Spectrometry there are two main methods to use - USEPA Method 245.7 and The European Norm EN17852 Water Quality - Determination of Mercury - Method using atomic fluorescence spectrometry (ISO 17852:2006).
We are happy to announce some dynamic changes in our blog content. Simply put, it was time for a change of philosophy and a fresh start. While our blog has always been a valuable resource for technical information, we recognized an opportunity to expand its subject matter, increase frequency, and ultimately create a more diverse, more useful forum. After all, we want users like you to benefit from its content, encounter something truly thought provoking, and come away with something valuable. We want you to return for the next post, and above all, we hope we move you to comment and participate in the discussion!
Tags: Blog Introduction
As government, the scientific community, environmentalists, medical professionals and the public at large recognize the persistent, bio-accumulative, and toxic nature of mercury, there is increasing demand for better control and monitoring of its release to the environment.
Analytical techniques for measuring mercury include cold vapor atomic absorption spectroscopy (CVAA), cold vapor atomic fluorescence spectroscopy (CVAF), and direct analysis by thermal decomposition. Each technique has advantages and disadvantages, I'll review each technique and provide tips for choosing the right one for various situations.
Selecting the right Hg technique really depends on your analytical needs. For some labs, the decision will be driven solely by the need to comply with a specific regulatory method. For example, if your lab is required to analyze samples using EPA Method 245.1, then you will need to use the technique of cold vapor atomic absorption spectroscopy (CVAAS). If you are required to follow specific regulatory methods, you may find the following information helpful.