The discussion must include information about the worst-case release scenario for regulated chemicals and the off-site consequence analysis. It's going to be a communications challenge, given how the public, media, and regulators respond to information about chemical hazards. Here are two recent examples:
A new threatChances are that you have read about the new hazards with chlorpyrifos. Bad news travels fast. The EPA announced in October 1999 that chlorpyrifos, a widely used pesticide marketed under the trade names of Dursban and Lorsban, may cause health problems in people at levels less than previously believed.
The story was picked up by all the major news wires and published in most community newspapers. "Letters to the editor" urge that chlorpyrifos should be banned. I suppose a regulatory coffin is being measured for chlorpyrifos now.
New revelationsChances are you haven't heard about the 1999 study indicating polychlorinated biphenyls (PCBs) do not cause cancer or other serious health effects in humans. Good news travels very slowly. The March 1999 issue of the Journal of Occupational and Environmental Medicine reported on the largest human study to date on the health effects of PCBs, conducted by researchers R. D. Kimbrough, M.D. and M. L. Doemland, Ph.D.
Kimbrough and Doemland studied 7,075 men and women who worked between 1946 and 1977 in two factories that used PCBs in the manufacture of electrical capacitors. The average follow-up time for workers spanned 31 years, which provided a long latency period to determine if there was any increase in cancer or other disease. "This new study provides strong evidence that even long-term human exposure to PCBs at higher levels than are found in the environment is not related to an increase in deaths from cancer or other diseases," concluded Dr. Kimbrough.
I doubt whether any regulator is urgently drafting guidelines to lessen the controls on PCBs enacted by Congress in the 1970s amid a public outcry for protection. Those fears were fanned by studies associating PCBs with numerous hazards including cancer, birth defects, infertility, mental retardation, and other very serious health effects.
Dr. Kimbrough, ironically, helped hammer a nail into PCBs' regulatory coffin. As a young researcher from the Centers of Disease Control, he discovered that PCBs were among contaminants polluting the Times Beach, Mo., area in the celebrated environmental case in the mid-1970s. Then in 1975, Dr. Kimbrough conducted a study that showed rats fed large quantities of PCBs in their diet developed cancer. Unfortunately, Dr. Kimbrough's most recent study has not received the same attention of earlier works.
Lessons learnedThe different reactions to good and bad news about PCBs and the quick spread of negative news about chlorpyrifos should remind us of the attitudes we face when communicating information about chemicals.
When we present information to the public on a chemical hazard, we must stress the positives over and over and over. There should be no intent to deceive, but since the truth is that good news about chemical hazards spreads slowly and bad news travels fast, we must be diligent and repetitive with our positive messages.
Our objective is to seek a proper balance of information on chemical hazards. The reality is we must tip the scales at times to help achieve this balance.
By Dan Markiewicz, MS, CIH, CSP, CHMM. Dan is an independent environmental health and safety consultant. He can be reached at (419) 382-0132, or by e-mail at firstname.lastname@example.org.