Dietrich Weyel, ScD – Carbon Monoxide & Noxious Gas Exposure Science

This week on IAQ Radio our Technical Director, Dr. Dietrich Weyel will review the science behind carbon monoxide and other noxious gas exposure. The detrimental effects of carbon monoxide have been well documented but there continues to be some controversy about the effects of carbon monoxide exposure especially low level exposure. This week we will get Dr. Weyel’s take on the issue and review over a hundred years of research on the subject.

Dr. Dietrich Weyel is our Technical Director and one of only a handful of people remaining from the heyday of the University of Pittsburgh, Graduate School of Public Health’s industrial hygiene program. His Doctor of Science degree is  in Occupational and Environmental Health. Too often people say that someone has forgotten more than others know about a subject but in this case it may even understate the issue. Dr. Weyel will discuss the literature from the masters of physiology and noxious gas exposure.

Z-Man’s Blog:

Carbon monoxide

According to Dr. Dieter Weyel, we have known for millennia that carbon monoxide (CO) is bad for you. Caveman likely learned about the need for ventilation the hard way. Coburn, Foster and Kane studied the uptake of oxygen and CO in the human blood stream.

Nuggets mined from today’s episode:

· When we wake up each morning our blood contains 7ppm of CO. At rest we breathe 15-16 times per minute. As our rate of respiration increases we both pick up and release CO faster.

· <1% of CO found in blood of healthy nonsmokers and is produced as the result of metabolic processes.

· Concern over low levels of CO are BS.

· Earth’s atmosphere is approximately 21% oxygen and 79% nitrogen, so our bodies are programmed to process 20% oxygen.

· Partial pressure is the driving force during inhalation for the exchange of carbon monoxide and oxygen. Increasing partial pressure drives gas into the blood. The hemoglobin in blood carries oxygen throughout the body.

· The transfer of O2 and CO2 occurs between the Alveolar Air and Capillary Blood, in the alveolus at the bottom of the lung. O2 and CO2 diffuse between the alveoli and wet side, the capillaries which transport the blood.

· Red blood cells have a >200X affinity for CO versus O2.

· Among other uses, hyperbaric chambers are used to treat people with carbon monoxide poisoning a method to increase the partial pressure of oxygen in inhaled air.

· Athletes train at altitude because Mother Nature compensates for higher altitude by producing more red blood cells. After about two weeks at altitude the body will produce approximately 7% more red blood cells. Removing a pint of blood, storing it and then adding it to the body before Olympic competition has been known to make the difference in a sport where fractions of a second separate winners from losers. This method is known as blood packing/blood doping which is no longer permitted by governing bodies.

· Dependent upon dose, oxygen can be both either beneficial or detrimental. Pure oxygen is the “ultimate oxidizer”.

· CO doesn’t accumulate or buildup in the body. CO does not kill red blood cells..

· Administering O2 to athlete’s between plays has no real benefit because their blood is already 99% saturated with O2.

· Ozone, Nitrogen dioxide and phosgene are destructive to alveol

An asphyxiant gas is a nontoxic or minimally toxic gas which reduces or displaces the normal oxygen concentration in breathing air. Breathing of oxygen-depleted air can lead to death by asphyxiation (suffocation). Because asphyxiant gases are relatively inert and odorless, their presence in high concentration may not be noticed.

Other toxic gases, by contrast, cause death by other mechanisms, such as competing with oxygen on the cellular level (e.g., carbon monoxide) or directly damaging the respiratory system (e.g., phosgene, ozone and nitrogen dioxide).

Notable examples of simple asphyxiant gases are: nitrogen, argon, and helium. The Earth’s atmosphere is made of 79% asphixiant gases (mainly nitrogen), and 21% oxygen. Source Wikipedia.

· Mother Nature doesn’t like dirt in the alveoli and uses macrophages to encapsulate and/or digest contaminates.

· Dr. Dieter Weyel, recalled a former teacher from Germany telling him; “never screw with Mother Nature, you will be a loser.”

The saying goes that we can always learn something and whenever I spend time with Dieter I learn much.

Z-Man signing off