Aren’t most oral thermometers now Mercury Free?
I don’t know the answer to that question. I do know that I encounter (Hg) mecury thermometers more frequently than their non-mercury replacements. Very recently (last couple of weeks), the EC banned the sale of new Hg containing instruments, but apparently that won’t effect those devices already on the market.
A few weeks ago, a doctor in Denver was using a sphygmomanometer that contained a large quantity of Hg. The instrument fell of the table, broke and released about one pound of Hg onto the carpet.
A couple of years ago, in a residence built in the 1920’s, some asbestos abatement knuckledraggers bashed out an old-fashioned residential gas regulation system in the basement and released about 70 pounds of Hg into the home.
Hg is all over the place; fluorescent lights, residential thermostats, heck, even those kid’s shoes with the flashing lights contain elemental Hg.
With test results below detectable limits, and no mercury recovered, is it possible that mercury was never present?
Not necessarily, since you never defined your “detectable limits.”
*Environmental Consultant: Hi Homeowner – Good news! I tested for Hg in your home, and it was below detectable limits. *
Homeowner: Great! By the way, what was your detection limit?
Environmental Consultant: Six pounds per house.
Homeowner: Uh… you mean … all you can tell me is that there is less than six pounds of Hg in my home.
Environmental Consultant: Yeah, well, you never actually asked me to define my data quality objectives before I started, you know…
Sampling for Hg is exactly like sampling for mould; until you have defined your data quality objectives, and performed your sampling according to those DQOs, you don’t know what the results mean, and you may have “test results” but you don’t have any data. Similar to a Pro-Lab mould report - you might as well have used a Ouija board.
[FONT=Arial]It is entirely possible to have half a pound of a gazillion little beads of Hg embedded in the carpet or the wood, and yet still have “results that are below the detectable limits." What were the detection limits that were used, how representative were the samples? And, did the samples meet the data quality objectives? (i.e. what were the DQOs). Do you have a “laboratory report” or do you have usable data?
Caoimhín P. Connell
Forensic Industrial Hygienist
(The opinions expressed here are exclusively my personal opinions and do not necessarily reflect my professional opinion, opinion of my employer, agency, peers, or professional affiliates. The above post is for information only and does not reflect professional advice and is not intended to supercede the professional advice of others.)