Tad4irish wrote:I know this may seem a bit unusual. I am trying to figure out blood achol contents readings and how to convert them to readings I can use in legal proceedings.

Currently, I recieve results using the formula of mg/l, but require them in g/100ml. Here is an example:

.037mg/1 liter

What would that equal in g per 100 ml? Anyone...if you could explain the work to me, I may even be able to figure it out on my own from now on

Thanks for your help....

Using the metric system this is actually quite easy. I hve no doubt yuo'll be able to do it on your own.

First things first: The metric system (The International System, or SI), has certain units that you're most likely familiar with - The gram, the meter, and the liter are the ones most people run across. It also uses a set of prefixes that modify the meaning of the main unit. milli, which is abreviated as "m", for example, means time 1x10^-3, or 1/1,000th. So then, a milliliter or ml (in the US mL is also used) is 1/1,000th of a liter, or 0.001 liters. kilo, abreviated "k", means 1,000 times. so a kilogram is 1,000 grams. The defintions for the units and the 20 prefixes you can use with them can be found at

http://physics.nist.gov/cuu/Units/. I'm not going to copy that information here, because I've already given you the prefix that you need, milli.

you currently have:

0.037 mg / 1 L and you want to convert that to g/100 ml

Well, since milli is 1/1,000th lets do the magic:

0.037 mg Ã· 1,000 mg/g = 0.000037 g. All we really did was move the decimal place three places to the right.

So, thats 0.000037 g / L. we want ml. there are 1,000 ml in a liter, so you've got:

0.000037 g / 1,000 ml. Again, three decimal places to the right.

but we don't want 1000, ml, we want 100 ml. Ten times less. So we multiply the fraction by 10 and we get:

0.0000037 g / 100 mL, (or 3.7 x 10^-6 g / 100 ml).

If you compare the fractions, you'll see that they are all equivalent.

0.0000037 g / 100 mL = 0.000037 g / 1,0000 mL= 0.037 mg / L

William J. Knight

Health Physicist

Los Alamos National Labs