Environmental pollutants and hazardous are major issues through which the modern world is suffering. Among all the environmental pollutants and hazardous materials how much contribution is from chemists (out of 100%) lets put rough estimate.
The answer to this can be very subjective. It is like saying how much of polution comes from airplane pilots. I have no data to support this but let's try common sense: most human waste comes from factories, mining, transport, institutions and households. There has to be a line between processed and unprocessed waste. If your question meant chemists in academia then I would say it is negligible (