ExposureBlog

Recently, an attorney friend of mine was presented with a client who had apparently been exposed to a chemical found in a commercial product.  The label noted a few chemicals as active ingredients, but also claimed that 99% of the chem was inactive.  And unidentified.  Well, the regulations (such as they are) on material safety data sheets allow quite a bit of leeway regarding disclosure.  For example, if a company discovers that a very, very common and cheap chemical, (sugar, for example) has some really interesting and heretofore unknown attributes–and the company wants to sell it for whatever they can get for it—well, they SURE don’t want to blurt out the magic ingredient in a material safety data sheet.  And, OSHA, apparently, agreed.  Result: some MSDS sheets are not particularly helpful.  The company simply claims the magic chemical is “proprietary.”   And that’s what you might see on the MSDS.

During my days with OSHA I approached this problem like this, informing the employer that he could choose the easy way or the hard way. (a) Easy way (tell us what the ingredient is and if it’s no big deal, we’ll keep quiet about it). or (b) hard way (don’t tell us and we’ll analyze it and publish the results on a billboard somewhere.)

In my mind, it wasn’t an idle threat. All of the lab directors I knew were chemists who were really interested in finding out what chemicals made up a commercial product.  We all knew the protocol—take about 20 ml of the chemical, wash with chloroform, extract whatever comes off and run it through a gas chromatograph/mass spec.  Sooner than later we’d get a list of chemicals.

Now, one would expect that things have changed for the better since then, but unfortunately that may not be true.  Back to my attorney friend.

I suggested he find an American Industrial Hygiene Certified Lab to analyze the sample. Then, ask for a GC/Mass Spec analysis. Now a gas chromatograph has a number of different detectors, and, the judicial use of these detectors can determine what chemicals are involved.

So he took it to the lab in his hometown–a big lab, actually, that normally checks the water supply for this sizable Western city.  We expected to know the answer within days.  Didn’t happen.  Instead, apparently since the the lab had an EPA contract, it ran the samples using their Haz Waste protocol.

In other words, since the language was EPA/Haz Waste, then they ran the sample(s) using this protocol.  It came up with a lot of NDs (none detected).  I phoned the lab director and asked him why he ran a haz waste protocol on something that was clearly not haz waste. His response: “The lady wanted to know if there was anything hazardous in the sample.”  Here, the laboratory apparently confused “hazardous” with “hazardous waste.”  Error number one. 

I then asked why he didn’t check for any of the ingredients that were listed on the bottle (as a standard check). His reply: “No one asked me to do that.”

And yes, he still charged $900 to the attorney for his “work.”  During the 30 minute discussion with the lab director, I found that he was one of these guys who started talking before the question was completed.  No wonder he didn’t get it right.  He probably wasn’t listening to a thing his customer said to him.

He also had no idea what the AIHA certification was all about.  In fact, he had never heard of such a thing.

Bottom line, if you want to analyze a chemical, FIRST ask the lab if they are AIHA certified. Not all labs are. 

Next, ask if the director has a chemistry degree. 

Third, ask if he uses EXTRACTION METHODS before analyzing chemicals.

Actually, your best bet is to simply ask an Industrial Hygienist to vet the lab before you send them any samples or write them any checks.  Not all laboratories are created equal.  Some only look for the chemicals that happen to be in their protocol pack.  If the chem isn’t listed, don’t expect them to find it.  Or even look for it.  The really horrible thing about this is, this outfit analyzed the drinking water for the entire city. 

Argh.

The Plaintiffs in this series of trials think so.  Former Corpus Christi welder Ernest J. Solis is the plaintiff in a trial being held in Cleveland.  His is one of 3,800 other lawsuits regarding Parkinsonism and welding fumes that have been consolidated in federal court there.  The toxin alleged to cause the Parkinsonism is manganese, an element occasionally found in welding fume–and, oddly enough, nuclear fallout.  Manganese is certainly a neurotoxin, but the symptoms it produces are fairly specific and don’t always correlate with classic Parkinsonism. According to Leikin and Paloucek, in the well-regarded (by me anyway) Poisoning and Toxicology Compendium, manganese-toxic patients “have a tendency to fall backwards, not have a prominent tremor and do NOT respond well to dopaminomimetic medication as opposed to idiopathic parkinsonism patients.” I’m betting one of the experts for the defense in this case will be Denver physician Scott D. Phillips.  He wrote an article in Greenbergs Occupational, Industrial and Environmental Toxicology, in which he had this to say about manganese: “Symptoms (of manganese exposure) are typical of parkinsonism. However, the brain lesions from manganese occur in the striatum and palladium in distinction to parkinsonism, in which the substantia nigra is damaged.”  He cites A Barbeau et al, “Role of manganese in dystonia,” Adv Neurol. 14:339, 1976.  Damage to the striatum and palladium is something that, presumably, can be differentiated from damage to the substantia nigra.

Then there’s the issue of naturally-occuring manganese in the environment.  For example, an average cup of tea may contain 2-7 ppm of manganese.

Making matters even more difficult for the Plaintiffs, the conditions of exposure to welding fume are going to be difficult to quantify years after the fact, especially when there may be no clear record of the specific types of welding rods that were used over the time period.  I can imagine the request for production: “all invoices for welding rods going back to 1960, all industrial hygiene monitoring results from 1970 to the present. . .”

Of course, I haven’t seen the court documents, but if the Plaintiff is asserting that welding rods -> manganese -> Parkinsonism in the welder, then it might be a tough case to make.

Prediction: 8:4 Defendant.

I’m back writing on the Exposure Blog after spending the last month on a very interesting toxic exposure case. This one, like many, involved a person who was overcome by a toxic gas (in this case, sulfur dioxide) that was released from the top of a 36-foot tall tank. Even though he was literally at the side of the tank when the release occurred, it was not easy figuring out how much sulfur dioxide he inhaled.

The molecular weight of sulfur dioxide—at about 64 gram molecular weight (add the mass of the individual atoms–sulfur and two oxygens)—is heavier than air (generally considered 29 gmw) but that doesn’t necessarily mean that it will drop like a rock out of the sky. For reasons I’ll get into in a later post, wind generally has more of an effect on relatively “heavy” molecules like sulfur dioxide than gravity.

And that day, the wind was blowing at a relatively leisurely 9 miles an hour.

So, part of the case was in place—we knew that sulfur dioxide was involved, and we knew the wind speed. The next thing was tougher—finding out how much sulfur dioxide was actually involved. That was not easy, and in a later post I’ll tell you how we came up with a value for the amount of sulfur dioxide released. While our calculations showed that about a thousand pounds of sulfur dioxide was released, the other side came up with around 700 lbs.

Interestingly, an expert for a third party involved in the lawsuit suggested only 76 pounds of sulfur dioxide came out of that vent.

The bottom line was beginning to appear: no one really knew exactly how much sulfur dioxide came out. I suggested we analyze the release using a mathematical procedure called a Monte Carlo simulation. There are several good programs that will do this sort of thing, but the one I use is called @RISK.

I wanted to be sure of my answer at the 95% confidence interval—that is, I wanted to be sure that there was only a 1 in 20 chance that the amount (in parts per million) of sulfur dioxide that the individual was exposed to was less than the number I reported.

To do this, I used the most conservative figure presented by the experts—in this case, it was 76 lbs of sulfur dioxide. I then used it as the *maximum* amount and input that value into the computer program. Then, for a minimum amount, I arbitrarily chose a value equal to about 2/3 of that value—about 50 lbs of sulfur dioxide–and added that as a minimum value.

Then, I made an assumption: suppose all the sulfur dioxide was evenly distributed in a given volume of air—no areas of high concentration, no areas of low concentration. What would the concentration be? Well, the individual exposed was surrounded by tanks, and since tanks take up space, there wasn’t a lot of air available for dispersion. Still, I needed a maximum volume and a minimimum volume. So I looked at aerial photos of the site to follow the path that the individual followed to the control room after being exposed. I chose the block of air surrounding this path—up to 36 feet high—as a maximum volume. For a minimum volume (which would give a higher concentration) I chose a percentage of that.

I also knew that the exposed individual probably received his maximum exposure initially—where the volume was smaller and the concentration higher. After deciding on these values as endpoints of the range, I plugged them into the program.

Concentration in parts per million (ppm) can be calculated based on this general formula:

(ppm)(V)(mw) = (grams)(specific gravity)(24.45)

where ppm = parts per million
V = volume of the area in liters
mw = equals molecular weight of the gas (here, 64)
grams = grams of substance emitted—here, the minimum was 50 and the max was 76.
specific gravity = how much the liquid weighs per cc. Since sulfur dioxide is a gas anyway, it wasn’t used in this calculation.
24.45 = the volume that one mole (here, 64 grams) of a gas occupies at 70 degrees F—which, as it turns out, was almost exactly the temperature at the time of the event.

Now, to the Monte Carlo simulation. Here is what it did: it took all the data and produced a distribution of values–like a bell curve. It also returned values associated with various parts of that distribution. In other words, there was a value at the far right end (95%) that was much greater than the value associated with the far left side of the distribution (5%). I chose the value associated with the 5% end of the curve.

In other words, there was a 95 percent chance that the concentration of sulfur dioxide associated with the input parameters (which I believed reflected the actual event) were greater than that found at the 5 percent mark.

The value that resulted was around 600 parts per million. This is more than 6 times the Immediately Dangerous to Life and Health (IDLH) value.

More later.