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Jeff Slivka | October 1, 2005

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Factory worker welding

It seems with each passing year some new environmental issue pops up. Albeit, "toxic" mold had pretty much dominated the discussion in the past few years, a new environmental concern is just rising to the surface of the multiple issues facing the construction industry. It is known as Manganism, and as obscure as it sounds, you can find plenty of information on the disease by "googling" it.

Manganism is a horrible disease associated with breathing welding fumes and other fumes containing manganese. If you are not aware of this debilitating disease, a Web-based search will result in over 45,000 hits—many are personal injury lawyers or other law-related websites, but you will find health and toxicological information as well. As for this article, I doubt it will be a catalyst for any action, but it may add some perspective and shed some light on a little known issue facing virtually any type of operation involving welding. At a minimum, it will be a subject or cool word to bring up at your next cookout or dinner party!

Starting with Manganese

Manganese (Mn) is a naturally occurring, silver-colored metal found in many rocks and soils throughout the world. When combined with other elements/chemicals, such as oxygen, sulfur, and chlorine, the resulting compounds have a variety of attractive uses. Such uses include dry cell batteries, fertilizer, pesticides, glazes, varnishes, water purification, fuel additives, and very prominent—as a hardener to increase strength in the production of steel. Mn compounds can dissolve in water; however, they are solids that typically do not evaporate. Mn compounds are typically emitted into the air causing an inhalation hazard to those working with or around it.

Everyone is exposed to small amounts of manganese in air, water, and food. Having proper amounts of manganese in your diet is known to be nutritionally essential for humans. Mn can be found in a variety of food sources such as almonds, mustard greens, kale, chard, raspberries, romaine lettuce, pineapples, collard greens, and maple syrup. The proper amounts can help your body utilize several key nutrients such as biotin, thiamin, ascorbic acid, and choline; keep your bones strong and healthy; help your body synthesize fatty acids and cholesterol; maintain normal blood sugar levels; promote optimal function of your thyroid gland; maintain the health of your nerves; and protect your cells from free-radical damage.

Driving the increased concern over manganism or Mn-related illnesses are the "toxic" fumes associated with welding rods and the application of pesticides containing manganese on a commercial basis. The fumes and sprays resulting from these operations, when inhaled for a period of time, can have toxic effects on the human body.

For those chemists, geologists, and plain old science buffs, here is a little test. See what you remember. Match up the Mn compound with its corresponding chemical composition:

Manganese Dioxide Mn3O4
Manganese Tetraoxide KMnO4
Potassium Permanganate MnO2

What Is Manganism?

Manganism is a Parkinson-like disease that supposedly results from the inhalation of "toxic" levels of manganese. Such exposure can cause irreversible damage to the central nervous system. Cases on the illness have been dated back to the late 1800s. Some individuals exposed to very high levels of manganese for long periods of time in their work can develop mental and emotional disturbances and slow and clumsy body movements. Workers usually do not develop symptoms of manganism unless they have been exposed to manganese for many months or years. Manganism occurs because too much manganese injures a part of the brain that helps control body movements. Exposure to high levels of airborne manganese, such as in a manganese foundry or battery plant, welding operations, or pesticide application, can affect motor skills such as holding one's hand steady, performing fast hand movements, and maintaining balance. Exposure to high levels of the metal may also cause respiratory problems and sexual dysfunction.

A complete list of symptoms includes the following.

  • Tremors of the arms and hands
  • Loss of balance
  • Drooling
  • Slow, unsteady, and decreased movement
  • Stiffness in arms and legs
  • Gait changes, including "shuffling of feet" and rigidity in arms
  • Fixed gaze—excessive periods of time with little or no blinking, or facial expressions
  • Impaired reflexes
  • Bradykinesia—the clinical term for "slow movement"

Now, you should understand that if you are experiencing any of the above symptoms it doesn't necessarily mean you have manganism. Take me for example. I experience many of the above symptoms, namely drooling, stiffness, and that dazed look on my face, and I seem to be getting slower every day. But the doctors have told me those symptoms have nothing to do with my levels of manganese in my system. That's just my look, and for many of you who know me, you'll agree. So don't go off and start providing any diagnoses or prognoses just yet.

Managing the Risk

Not to oversimplify, but the techniques for managing exposure to manganism are similar to almost any other airborne hazard. Below are just some suggestions that can be applied.

  • Employee education. All personnel involved or around those activities, operations, or processes that use Mn-related products should be trained, at minimum, on proper usage, use of personal protective equipment (PPE) and preventative measures and emergency response protocol.
  • Mn substitute. Where possible, substitute the Mn for a product that does not have Mn. By utilizing this technique you actually eliminate the hazard all together.
  • Dust suppression. For manufacturing processes, use dust control methods or apply in a confined area.
  • Personal protective equipment. This probably is the most important and easiest to apply for construction-related activities. It is amazing that after all we have learned on the issue that you still see many welders without respiratory protection. Utilize proper respirators that will capture and prevent inhalation of the crystalline silica. Wear disposable or washable protective clothing.
  • Conduct regular air monitoring to ensure that control systems are working. This can provide early indications and prevent further damage.
  • Post warning signs around areas contaminated with Mn-related materials or dust.
  • Avoid any type of eating or drinking in areas where material or dust containing Mn exists.

Insurance Impact

From an insurance perspective, the major concern would be exposure to employees and, of course, workers compensation related claims. However, in those states that are lax when it comes to third-party-over action claims, many construction firms can easily find themselves in the middle of a such a claim, and the primary issue at hand will be—is Mn a pollutant? We could probably split 50-50 on whether or not it is, but I'm willing to bet that most commercial general liability (CGL) insurers would look to decline via the pollution exclusion in the policy. Nonetheless, when it's all said and done, coverage may still be afforded.

If an organization is looking for an alternative to insure against such an exposure, they can always look to a contractor's pollution liability or CPL policy. The way CPL policies are structured nowadays, they will provide coverage for pollution-related third-party-over action claims. Each insurer accomplishes this with a different approach; nonetheless, it can be a sound alternative if you are looking to select a financing mechanism for the risk.


As I stated in the beginning, this is merely a new issue that is developing. It would be a stretch to call it a major issue at this point. With that said, organizations cannot remain ignorant to the exposure or to the impact it can have on an organization—exposure to the workforce and exposure to potential third-party liability. It would be prudent for any organization to add this Manganese exposure to their overall environmental risk profile to methodically analyze the risk and manage it.

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