745 Welding, Cutting, and Brazing Safety

Top 10 Chemical Exposures

4. Manganese (Mn)

While it is an essential trace element for human health in small amounts, excessive exposure—particularly through inhalation of fumes or dust—can be toxic.

Exposure Risks: Manganese is a metal commonly used in the production of steel, welding rods, batteries, and other industrial materials.

Health Effects: Prolonged or high-level exposure to airborne manganese, such as in welding operations or metal manufacturing, can lead to a neurological condition known as Manganism. This disorder presents symptoms similar to Parkinson’s disease, including tremors, muscle rigidity, slowed movements, and postural instability.

Unlike Parkinson’s, Manganism does not typically respond to standard Parkinson’s medications, making prevention critical. Chronic exposure can also impair cognitive function, mood, and motor coordination, especially with long-term occupational exposure.

5. Lead (Pb)

Lead (Pb) is a dense, soft, bluish-gray metal that is naturally occurring in the Earth’s crust. It has been used by humans for thousands of years due to its malleability, corrosion resistance, and low melting point.

Exposure Risks: It's commonly found in batteries (especially lead-acid car batteries), certain types of solders and pipes, radiation shielding, ammunition, and historically in paints and gasoline. It may be also present in certain solders, pigments, protective coatings, and older construction materials such as plumbing.

Health Effects: It is highly toxic and poses significant risks to human health, particularly through inhalation of dust or fumes and accidental ingestion. Lead primarily affects the nervous system, leading to symptoms such as headaches, memory loss, irritability, and, in severe cases, encephalopathy. It also damages the kidneys, impairs blood cell production, and can cause hypertension. Of particular concern is its impact on reproductive health and child development: lead exposure during pregnancy can result in miscarriage, low birth weight, and developmental delays. In children, even low levels of lead can cause irreversible cognitive and behavioral impairments. There is no safe level of lead exposure, making strict adherence to safety practices—including the use of PPE, safe handling procedures, and routine blood level testing—critical in any environment where lead is present.

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