Welding operations come with all kinds of occupational hazards – electric shocks, possibilities of fire and burns if the welder does not have proper protective gear. But exposure to welding fumes may also cause serious health damage, New research shows that components of welding fumes, when they accumulate in the body, can cause DNA damage.

Welding fumes have been categorised as possible carcinogens and the new study depicts the possible mechanism by which they may cause damage to the body. Scientists from Annamalai University in Chidambaram and the Indian Institute of Science in Bengaluru conducting a study with rats to investigate how inhaling welding fumes may cause DNA damage and oxidative stress among other things. Oxidative stress is a disturbance in the production of free radicals of oxygen that may be harmful and the antioxidants that counter them.

They found that rats with chronic exposure to welding fumes has an accumulation of chromium in very high concentrations in their lungs. This chromium was found in two oxidative states including the chromium (VI), which is dangerous because it is soluble and can pass through cell membranes to enter cells.

Once inside a cell, this chromium (VI) interacts with DNA causing oxidative stress that breaks DNA strands apart. When this happens the cell either deploys antioxidants to repair the damage or, if the damage is too severe, kicks off the process of cell death.

The research team observes that the rats exposed to welding fumes had both elevated levels of damage sensors and significant levels of cell death indicating severe damage from the fumes and the chromium. They also found that exposure to welding fumes alters the expression of 37 genes involved in oxidative stress, detoxification, inflammation, DNA repair, cell cycle progression, and cell death.

The study was published in the journal Toxicology Letters.