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From Our Readers: Advice, Reflections, and Praise
CIH EXAM PREP Maggie Murphy got a lot right in the article “Applying and Preparing for the CIH Exam” (October) but missed one reference that should be in any student’s library, and that is the third edition of AIHA’s The Occupational Environment: Its Evaluation, Control, and Management. This book is a wonderful set of texts that really enhances anyone’s study for the CIH exam.
One other option is to enroll in a master’s degree program. When I missed passing the CIH exam the second time, I said to myself, “If I’m going to have to study that hard for another six months, I’m going to get a master’s degree,” and I did. Two terms into this study effort, I took the CIH exam for the third time, and I passed!
At least two institutions offer an online master’s program, which can be accomplished mostly at home (my program, at Tulane University, had a required ten-day, hands-on lab).
One other thing: don’t be disappointed if you don’t pass it the first time. Take it as a learning experience and try again and again if necessary.
I’m raising two points of clarification about the ethics article in the November Synergist (“Knowing When to Quit”). I’m not directly addressing the ethics issues. In the United States, prescribing marijuana is regulated exclusively by the Drug Enforcement Agency (DEA). Marijuana is a Schedule 1 drug and cannot be legally prescribed. State laws allowing the use of medical marijuana do so through certificates or some similar mechanism and carefully avoid use of the term “prescription.” State laws vary, but generally, an injured employee is not required to file a workers’ compensation claim. Even if a claim is not filed, work-related injuries are generally excluded from other medical insurance coverage. The employee who chooses not to file a workers’ compensation claim may, under some very limited circumstances, file another liability claim. Daniel J. Brustein, MD, MSIH, FACOEM, CIH-Retired Certified by the American Board of Internal Medicine
Thanks to Renee Hartsook for the fine article “Plain Language: The Antidote to Alert Fatigue?” (December). It was actually the pull quote about reliance on “influence more than authority” that caught my eye. After reading the first paragraph, I immediately recalled an extraordinary influence on my first level of formal training in our professions.
Her name was Chris Nichols, PhD, a longtime teacher of chemistry at the British Columbia Institute of Technology, circa 1982. It was the first year of a new program leading to a Diploma of Technology in occupational health and safety, also the very first of its kind in Canada. Chris made the astute comment: “The problem with chemists is that, after a few years of practice, they begin to think that the chemicals they work with are their friends.”
After all these decades, I’ve never forgotten her words. Nor have I forgotten that OEHS professionals can easily talk over the heads of workers and management. Eyes glaze over when we use technical talk, and most people don’t need reminders of how smart we are. Most people just want the straight goods.
Laurence Svirchev, MA, BS, CIH Svirchev OHS Management Systems

NANOMATERIALS EXPOSURE LIMITS I would like to congratulate Jeffrey L. Behar for his article “Protecting Against Engineered Nanomaterial Exposures” (December). The article notes that there are no regulatory standards for engineered nanomaterials, which is true. But I wanted to add that NIOSH has two recommended exposure limits for these compounds. The NIOSH REL for carbon nanotubes and nanofibers is 1 µg/m3 and the REL for nanosized titanium dioxide is 300 µg/m3.
Debbie Dietrich, CIH
LEADED VS. UNLEADED Thank you, Eva Glosson, for the excellent article on improving lead standards (December, “Rethinking the Lead Standard”). I am pleased to hear about these new standards.
A history lesson:
I worked for Shell in British Columbia from 1965 to 1970 and have worked in the field of industrial hygiene since 1973. I had a front-row seat to all the changes in gasoline marketing as a car owner since 1963. I worked with a lawyer representing a farmer whose cows died from lead emitted from a battery recycling plant in the 1970s.
For the record, unleaded regular gas was introduced in the U.S. and Canada in the early 1970s, and, for a time, gas stations sold unleaded regular, leaded regular, and leaded premium. One of the reasons for unleaded gas was that, starting around 1970, emissions control systems in many cars relied on catalytic converters, and lead rendered those ineffective. Apparently one tank of leaded gas would kill a catalytic converter. Many catalytic converters died very young because owners used the cheaper leaded gas.
New cars sold in Canada from the early 1970s on had to be able to run on unleaded regular. I ran my 1976 Honda Civic on unleaded from day one, but most people were using the less expensive leaded regular. In those days, mufflers rusted out in 18 to 24 months. The first muffler in my Civic lasted over 30 months. The guys in the muffler shop were amazed it had lasted that long.
A few years later, leaded premium was replaced with unleaded, which had a lower octane rating. Until then, our 1967 Volvo ran on leaded premium, and still, the engine would sometimes knock. Many older cars had a need for lead beyond octane and would apparently develop fatal engine problems on unleaded gas. The solution was to reduce the compression ratio by installing a thick head gasket and run on leaded regular, which was widely available through the 1980s. We were using leaded regular until we sold the Volvo in 1983. We used nothing but regular unleaded in the 1983 Volvo that replaced it.
The last leaded regular was sold in Canada in 1991, and it was still available in Washington state then. Washington was one of the last states to phase it out.
The public health impact of eliminating lead in gasoline has been substantial. A 2013 Health Canada report says, “Although blood lead levels (BLLs) have declined by over 70% in Canada since 1978–1979, lead is still widely detected in the Canadian population. In 1978–1979, approximately 27% of Canadians aged 6 to 79 years had BLLs at or above 10 micrograms per deciliter (μg/dL) compared with less than 1% of Canadians today” (PDF).
Unleaded gas and emission controls have greatly reduced the maintenance needs of automobile engines. The spark plugs in our 1967 Volvo needed the gap adjusted after 3,000 miles and were replaced at 6,000 miles. I don’t recall ever replacing plugs in my 1986 Honda Civic, which I drove until 2001. My 2001 Ford Focus still had its original plugs at 160,000 kilometers, or 100,000 miles, when I sold it. It had passed emissions testing easily, until the emissions testing program was phased out.
How long do mufflers last in cars built since 2000? I did not replace the muffler in the 2001 Focus in 18 years.
Ed Chessor, PEng, CIH-Retired