In rec.crafts.metalworking MMonheit wrote:
snip
Even today, the MSDS is not adequate. For example, regarding
Manganese, the warning reads, "Long-term (chronic) overexposure to
welding fumes can lead to siderosis (iron deposits in lung) and may
affect pulmonary function. Manganese
overexposure can affect the central nervous system, resulting in
impaired speech and movement. Bronchitis and some lung fibrosis have
been
reported. Repeated exposure to fluorides may cause excessive
calcification of the bone and calcification of ligaments of the ribs,
pelvis and spinal
column. May cause skin rash."

But they don't say that the problem is irreversible. That is it
progressive.

MSDS are not well-written for end users.
It would be really nice if there was a little column saying how much
you have to do to damage yourself with the chemical in various ways.

E.G. Water:
Airway: May cause death if breathed in quantity. If still breathing
after immersion, professional aid should be sought as lung infections
can develop.

Skin: Extended exposure will cause softening of skin, and may allow fungal
infections to develop.

.....