Current Air/Water Quality: Deciphering EPA “Data”

This morning EPA Administrator Lisa P. Jackson tweeted that EPA is monitoring air and water quality and even linked to the “data” EPA is making available:

EPA continues to monitor enviro quality in Gulf. For data:

Now, I’m no scientist, but I am a pretty smart lady, so I set about trying to interpret the “data” Lisa provided us. I enlisted the help of some other intelligent folks as well. After close to 45 minutes we still did not have a clear understanding of what the air or water quality was in any particular area, in relation to what the acceptable limits are for each chemical being tested.  This is not my idea of “transparency in reporting” from the EPA.  So let me take you through what I did learn.

First, after getting no where with the illegible wording on the main site (here’s a sample report – helpful?), I found out the EPA has a TAGA (Trace Atmospheric Gas Analyzers) bus running along the coast monitoring for Benzene, Toluene and Xylene.

Great, so I can just go find the information for my area and determine what the current Benzene levels are, right? Not so fast. The air quality reports are all listed in Latitude and Longitude only, so I then had to take the Lat/Long numbers, visit this site to enter the coordinates and get map data. They aren’t even segmented by state. I happen to have a pretty good idea of Mobile’s Lat/Long coordinates so I took an educated guess with one.

The first point I entered ended up being for Innerarity Point, in Perdido Key, just east of the Florida/Alabama state line. The measurement for Benzene at this location on 6/25/10 14:23 was 72.831 ppb.

Whew. Now I had something: a date, time, meaningful location, chemical being measured and amount detected. Now that is data. But for the average citizen (which I am) I still didn’t have information. I now had to ask: What does this mean? In order to know what a Benzene reading of 73 ppb means to me I need to know what is the acceptable limit for Benzene. That information is stored no where near the reported findings, so I started searching the EPA site.

Finally I found the permissible Benzene limits for the EPA. The problem is the EPA reports the results in ppb (parts per billion) – 73 in this case. That would be helpful, IF EPA reported acceptable limits in ppb, which they do not. Here is the listed EPA acceptable limit for Benzene:

Benzene:  20 µg/m3 and below

This makes it difficult to decide if your air quality is bad, even if you are able to locate your area and find reported numbers on these chemicals. More digging…

One of my brilliant researchers finally found a formula to convert µg/ m3 to ppb:

µg/ m3 * 24.46 / molecular weight of compound = ppbv
Smart – now we can just run the calculation! Except that we were still missing one critical piece of the formula: molecular weight. More digging…
Finally we found this:

The EPA has set the maximum permissible level of benzene in drinking water at 5 parts benzene per billion parts of water (5 ppb).

There’s a Benzene permissible limit in ppb – awesome! But wait, we’re looking at air quality measurements, so the permissible level of benzene in drinking water isn’t actually helpful. Finally, we looked to OSHA (Occupational Safety and Health Administration), where we found this:

The Occupational Safety and Health Administration (OSHA) has set limits of 1 part benzene per million parts of workplace air (1 ppm) for 8 hour shifts and 40 hour work weeks.

Now we’re getting warmer. One more quick calculation to convert ppm to ppb gives us OSHA limits of 1,000 ppb for benzene in workplace air. It’s not outside air, but after all this time and effort, “it’s close enough for government work”.

Now we can go back and compare the level from Innerarity Point of just under 74 ppb to the OSHA workplace air limit of 1,000 ppb and find that, on June 25th, at 1:43 PM, the benzene level recorded by EPA near Perdido Key, Florida was within the limits established by OSHA.

Again, you had to guess at your area based on latitude and longitude numbers. Otherwise it’s a lengthy series of trial and error to figure out which numbers apply to you. And that’s just for 3 of the chemicals that are being tested!

Am I the only one that sees a problem with the way the Environmental Protection Agency is recording and reporting information to the public during this time of crisis??