Working in industrial hygiene presents an interesting paradox — the more you learn the less you know.

Consider a material safety data sheet. As a novice industrial hygienist you can study its contents and know a lot about the hazards of the product. From information in the MSDS you can provide hazard communication training to employees. More importantly, you can measure worker exposure against established limits. And if limits are not exceeded your job is pretty much finished.

Or is it?

IH work cannot be completed using superficial information. You must dig deeper before you can conclude that your job is done.

Caveats & disclaimers

For instance, almost every MSDS contains the legal disclaimer that the user must verify the accuracy and completeness of information in the MSDS. Exposure limits, particularly Threshold Limit Values (TLVs®), contain caveats and disclaimers telling users to consult further information before reaching conclusions.

Disclaimers are part and parcel of MSDSs because the amount and quality of hazard information changes over time. A main caveat with limits (e.g., TLV®) is that they will not adequately protect all workers.

Who might not be protected by a TLV®? The TLV® booklet says an IH must consider a worker’s age, gender, ethnicity, genetic factors, lifestyle choices (diet, smoking, abuse of alcohol or drugs, etc.), reproductive capacity (including fetal development), work levels (light vs. heavy), cardiac and respiratory output, and variations in temperature and relative humidity.

Down the rabbit hole

No single document can meet our information needs. So we turn to the Internet, which is like jumping into Alice’s rabbit hole, where we might find a bewildering world of seemingly unending and controversial data. How far must an IH go into the hole before conclusions can be reached?

Conclusions could be reached quickly if a workforce population was predictably uniform. Unfortunately, worker populations are diverse today and expected to become more so in the future. And as science changes so do our views. Some IHs may never climb out of the rabbit hole.

Searching for answers

How would you respond if an employee asks you if workplace exposures could reduce his sperm count? It’s a valid and serious question. Upwards of ten percent of couples in the U.S. are infertile, and about half of the problem comes from the male partner. Low sperm counts are a key reason why some couples can’t conceive.

Traditional paper references on the topic won’t be much help:

• OSHA regulations are silent on the issue.
• Some chemicals are known to slow or stop the production of sperm, but an MSDS may not alert you to this hazard. NIOSH has a five-page pamphlet on male reproductive hazards with general but no specific information.

Jump into the Internet rabbit hole and you’ll find conflicting studies and varying recommendations.

Welcome to the IH paradox. The deeper you dig the more uncertain you may become.

Technological advances allow many people to take health matters into their own hands. A few years ago, a person would visit a doctor or clinic and “create” a fresh semen sample. Today, for less than $40, a person can order a test kit online that will measure sperm count in the privacy of his home. Two test results with sperm concentration less than 20 million/mL might indicate male infertility. Assume the tests have told the employee his results are low.

Once you’ve located all the workplace hazards that can reduce sperm counts, are exposure limits OK? For example, heat can reduce sperm count. Lead can, too. But does the TLV® for heat stress and lead address sperm counts?

You probably feel your workplace is safe regarding the issue of sperm counts. But when you consider more information, does your doubt grow? Say hello to the IH paradox.

Covering your butt

The more you understand a hazard the more likely you are to add caveats and disclaimers to your training and reports. In my early days as a CIH, conclusions in my reports were succinct. I acted on readily available information and that was that. I didn’t feel disclaimers and caveats were necessary.

Nearly 20 years later I’m a different CIH. I’ve learned more, and with Internet searches more information is readily available all the time. So I’m more cautious to draw conclusions. I routinely include caveats today in my training and reports when I encounter uncertainty, which seems to occur more and more often. And I’m more likely to conduct additional sampling to help clarify issues.

Industrial hygienists are not the only professionals running into this paradox. A study published in the June 2005 issue of the Journal of the American Medical Association found that 93 percent of medical doctors said they sometimes or often practiced “defensive medicine.” This includes ordering additional tests and including caveats and disclaimers to conclusions or actions.

Why is this necessary? Professionals must avoid the claim that they were negligent, incompetent, or otherwise ignorant of things they should have known and actions they should have taken. Are you negligent in not informing employees of what workplace hazards may impact their sperm? Do you, as an agent for your employer, have a duty to protect the reproductive health of workers? Before you answer these questions you must consider the legal, political, and ethical issues in this matter. Back into the rabbit hole you go.

Getting help

Workplace hazards to sperm are just one of many and growing health and safety concerns we face as an IH. Ironically, many of these hazards might have existed for years without notice but as more information comes forth we plunge further into the IH paradox.

To help reduce negligence and other concerns, team decisions should be made when the IH paradox arises. Ideally, the team should consist of you, a management representative, an employee representative, and an outside expert.

You will need to educate the team on the issue and allow team members to conduct their own Internet searches. Conclusions made by the team should be communicated and documented to all affected employees. Since the amount and quality of hazard information varies over time, you should plan to revisit the issue at least once a year.

Welcome to the IH paradox.