Welders have an increased risk of Parkinson’s even if manganese exposure is within legal limits according to a recent article in the on-line journal Neurology, which is the journal of the American Academy of Neurology.

Welders who did flux core arc welding in confined spaces were particularly vulnerable to Parkinson’s according to the study. Workers in Nebraska who would attempt to get compensation for manganese exposure would face problems if the onset of symptoms happened after an employee stopped working. A court case in Nebraska held that an employee who didn’t experience symptoms of an occupational disease until after he retired was not entitled to be compensated because he wasn’t earning wages when the injury manifested. Welders and others who are exposed to manganese on a regular basis should recognize the early symptoms of Parkinson’s such as tremors, difficulty sleeping, constipation and loss of smell and report these symptoms to their doctors and employers as soon as possible so they can be treated under workers compensation and receive workers compensation disability benefits.

The study comes on the heel of a final flurry of OSHA rule making at the Obama administration. In May 2016 OSHA finally adopted a silica exposure rule for workers exposed to sand particles which can cause lung problems. Earlier this month OSHA lowered exposure thresholds for berrylium which is another pulmonary hazard, particularly for construction workers.

The example of beryiluim could explain why exposure to manganese levels at supposedly safe levels can lead to occupational disease. Those supposedly safe levels of exposure may not actually be safe. Another explanation about why supposedly safe levels of manganese lead to Parkinson’s could be found in the practices of the coal industry. Howard Berkes of NPR and Ken Ward Jr., author of the excellent Coal Tattoo blog for the Charleston (WV.) Gazette Mail teamed up to report on how coal companies would fudge coal dust level testing to make it appear that miners were exposed to much lower levels of coal dust than they were actually exposed.

OSHA’s rules could also be reversed by Congress under the Congressional Review Act. In 2001, the OSHA ergonomics rule that would have reduced musculo-skeletal injuries was reversed under this law.