Some samples found unsuitable even for irrigation purposes
Links:
[1] http://admin.indiaenvironmentportal.org.in/news/study-reveals-organic-pollution-six-river-basins
[2] http://admin.indiaenvironmentportal.org.in/category/newspaper/hindu-new-delhi
[3] http://admin.indiaenvironmentportal.org.in/category/thesaurus/kerala
[4] http://admin.indiaenvironmentportal.org.in/category/thesaurus/water-pollution
[5] http://admin.indiaenvironmentportal.org.in/category/thesaurus/organic-pollutants
[6] http://admin.indiaenvironmentportal.org.in/category/thesaurus/water-quality
[7] http://admin.indiaenvironmentportal.org.in/category/thesaurus/kasaragod-d
[8] http://admin.indiaenvironmentportal.org.in/category/thesaurus/kollam-d
[9] http://admin.indiaenvironmentportal.org.in/category/thesaurus/drinking-water
[10] http://admin.indiaenvironmentportal.org.in/category/thesaurus/health-effects