A Dust-free Chalk for Teachers

摘要

They might love their jobs but what teachers loathe is the cloud of white dust which settles in layers on their hands, shoulders, eyes, enters their respiratory tracts, and even enters into the electronic equipment around the classroom. Though chalk is made of mostly non-toxic substances, its accumulation in respiratory tracts can cause serious chronic illnesses such as asthma. To improve the situation, Partho Ghosh, director, Central Salt and Marine Chemicals Research Institute (CSMCRI), started a project to create a clean chalk and a suitable duster in 2002.