October 27, 1992

Ms. Betty Allen
Route 4, Box 282B
Salem, Indiana 47167

Dear Ms. Allen:

Thank you for your letter of August 27 regarding male infertility and welding engineers. Your letter was forwarded to Occupational Safety and Health Administration (OSHA) the Directorate of Technical Support for response.

It is not possible to cite specific exposures and toxicological effects based on a job title. Welding engineers may be exposed to a wide variety of hazards depending on the industry, the duties, the materials welded, the adjunct processes, the equipment used and many other factors. Some general remarks, however, can be made concerning typical hazards from welding operations.

Health hazards from arc welding and cutting result primarily from exposure to metal fumes and to ultraviolet (UV) radiation. The UV radiation can burn the eyes and skin; chronic exposure can result in cataracts and skin cancer. Typical metal fume exposures include compounds of arsenic, beryllium, chromium, cobalt, copper, iron, magnesium, manganese, molybdenum, nickel, tungsten, and vanadium. Of these exposures, only manganese is associated with infertility; manganese is known to cause impotence and reduced sperm count (hypospermia).

Hazards from gas welding and brazing differ from arc welding hazards primarily because they involve metals with lower melting points. One such metal is lead. Overexposure of male workers to lead compounds is known to decrease the sexual drive and reduce the ability to produce healthy sperm. Sperm effects include malformed sperm (teratospermia), decreased number (hypospermia) and decreased motility (asthenospermia). Fumes from other low-melting point metals, such as cadmium, silver, tin and zinc, have not been implicated in causing infertility.

The voltage supplies for electron beam welding often emit X-ray radiation. Plasma arcs can also emit X-rays and many processes use X-ray radiography to determine the quality of welds. Radiation from X-ray emissions can cause sterility; however, the dose of this radiation must be sufficient to produce this effect. Other effects are known to occur at much lower levels.

Welding radioactive metals can increase the exposure hazard from ionizing radiation. Heating materials which emit alpha particles can bypass the body's protective mechanism for alpha radiation.

Normally the skin protects the body from alpha radiation because this type of radiation cannot penetrate it. When the material is vaporized, it becomes airborne and permits the radiative particles to be inhaled. When the alpha particles are inside the body, the radiation can be readily absorbed. As with X-ray radiation, the resulting effects depend on the exposure level.

Other inhalation hazards can result from the reaction of air with heat and radiant energy to produce nitrogen dioxide, ozone and carbon monoxide. Inert gases used to shield the weld, such as carbon dioxide, helium and argon, can also produce inhalation hazards. Flux coatings on the rods or other alloys are known to cause severe short-term illnesses. None of these hazards, however, are associated with infertility.

For general discussion of welding hazards, lead, manganese and ionizing radiation exposure are possible sources of infertility. These sources, however, do not constitute a complete list of the biological insults that could produce infertility. Welding processes can involve materials which might be contaminated with solvents, greases or oils; welding can include operations that inadvertently vaporize plastics, rubber or other compounds; and welding can produce radiant energy that can affect adjacent processes and produce toxic gases or compounds.

In other words, there are many elements of the specific worksite that must be reviewed to make an informed judgment. We will be happy to assist you if you need further information about specific processes or hazards. Please contact Hank Woodcock at (202) 219-7065, if we can answer any additional questions about welding hazards.

Sincerely,



Patricia K. Clark
Director
Directorate of Technical Support