For 45-year-old weaver Narayana P, who worked at a small silk yarn-processing unit in Magadi town in Karnataka, March 5 is a day he will never forget.
"I got in to work as usual at 9 am and began rinsing 10 kilos of raw silk before putting it on the spindle to prepare threads. Then something I had never experienced before happened. As soon as we turned the machine on, we smelt some pungent chemical. And then I felt a burning sensation in my eyes as they began swelling. Soon, everything around me seemed blurred. Then, I could not see anything at all. My employer took 11 of us to an eye clinic and then to a hospital in Bangalore (50 km away). I don't know if I will be able to see again."
Narayana is one of at least 60 weavers from Magadi who have lost their eyesight, maybe forever, in the last three months after handling the chemically treated silk yarn, samples of which have been sent by police to a forensic laboratory to ascertain the chemicals present in it.
M Nanjundaswamy, 32, in whose factory Narayana and the others worked for Rs 200 per day, has shut down his unit and works at a roadside eatery.
"This consignment of raw silk yarn was probably treated with chemicals by suppliers to increase its weight and give it the semblance of better quality yarn which costs twice as much — Rs 2,500 per kg," he said.
Nanjundaswamy said the yarn is supplied by traders from various parts of the country through middlemen and it was not possible to say where these toxic supplies came from.
The blinding effect has caused panic in Magadi, with six units having shut down and another 24 on the verge of closure because workers are refusing to touch what may be their last tryst with the visual world.
Dr LS Malthesh, an ophthalmologist who examined 20 weavers, said the injuries seemed temporary as they were caused to the cornea, the outermost layer of the eye.
"The weavers I have seen don't have retinal injuries. Untreated injuries to the cornea might lead to infection, which can easily spread to rest of the eye. Any injury to the retina — the membrane connected to nerves carrying the stimulus to the brain — might lead to permanent blindness."
Many weavers have already begun migrating to Bangalore in search of hard labour, particularly in the booming construction industry.