A recent news article indicated the following challenges for the paper industry of China. The same challenges apply to the industry in much of Asia, and to some degree throughout the world. Overall, the industry dumps 3 billion tons of waste into the country's waterways each year. China's National Council for Light Industry wants to take steps to reduce this pollution. The Council closed down 30 such highly polluting factories in 1994, and will seek to control the growth of smaller factories.
Low technology pulping processes leave chemical residues in the waste water.
However, this is a challenge of the pulping method, not a challenge of annual fibers.