At the beginning of almost every HAZMAT class I teach I always poll the classroom for their point of view and level of knowledge. One of the questions I ask is based on the following 3 hazards, which one would you rather work with? Chemical? Radiation? Biological? There is no right or wrong answer, but I want to know where they are “coming from”.
My rational is that a Radiation hazard is most easiest to manage because it is measurable and well studied and thus more manageable. There are finite radioactive isotopes that occur in nature about 3000 in laboratories as opposed to approximately 80,000 pathogens, and another 80 to 100,000 chemicals that are in marketplace.
Biological hazards are often difficult to manage because you need a “zero threshold” meaning, you can be exposed to no level. You are able to achieve this through the use of protective equipment and decontamination protocols.
Chemical hazards are the most difficult to deal with because out of the 80 to 100,000 chemicals you may encounter in the real world, there are only exposure standards for several thousand. So you often don’t know what if any the safe exposure level is. If you have a mixture of chemicals, let’s say in smoke, you have a bigger problem and need to run a formula to determine the safe level if the chemicals target the same organ or part of your body.
A cigarette company used to market their cigarettes stating that their competitors had 600+ chemicals in the smoke. In a case like 9-11 in NY the number of chemicals in the smoke according to one researcher interviewed last night, the number of chemicals was in the thousands. Why does that matter?
Any first year industrial hygienist, toxicologist, or emergency management professional knows a mixture poses a whole set of problems. The standard formula put out by industry groups (the ACGIH) is an additive model; the effect of two or more chemicals together is equal to the sum of each chemical. There is also a synergistic model where the result is greater than the two or more chemicals. The ACGIH Biological Exposure Limit Guide explains it this way: “When two or more hazardous substances have a similar toxicological effect on the same organ or system, their combined effect, rather than either individually, should be given primary consideration. In the absence of information to the contrary, different substances should be considered as additive where the health effect and target organ or system is the same.” Then gives a formula to calculate what the exposure level should be.
The number of chemicals in WTC dust was in the thousands, and also has a distinct “fingerprint” (chemical profile) that has been documented. That means when they are plugged into the formula the exposure limits would probably be close to zero (0). Common industry “rules of thumb” indicate that ambient standards for the general public should be 10% of the occupational standard. So arguably the safe level should have been 10% of the formula.
With this in mind, the emergency managers who stated that the air was safe either didn’t know or didn’t care that what they were saying was wrong. Several years later it was reported that the government was more concerned about getting the economy going again and giving a sense of normalcy rather than concerns for health hazards.
If a similar situation happened in private industry, people like me would probably go to jail let alone be found liable for all the illnesses. But because the government did it I guess many people feel that it’s OK. Since the government has Sovereign Immunity (can’t be held responsible for its actions), it seems the legal and political system agrees with them. The reasons the emergency managers allowed this situation to occur also is that during disaster’s OSHA regulations are suspended.
During an emergency situation I can understand the need for urgency, but once Ground Zero became an environmental cleanup, standard protocols should have been followed. If the managers knew there was a possibility of jail time for this level of mismanagement (like every private employer in this country), then perhaps things would have been handled differently.
Perhaps with Christine Todd Whitman’s admission yesterday, perhaps revoking Sovereign Immunity for environmental crimes is an idea whose time has come. I don’t blame her personally, I doubt she has the credentials to understand the data. However, where was the outcry by the EPA/OSHA and public health people at the time and the news media?
This two sets of rules one for government officials, one for everyone else must stop.