A study done by the students of Thane College revealed that the creek water had become polluted, as the fish in the creek had traces of mercury and lead in them.
Links:
[1] http://admin.indiaenvironmentportal.org.in/news/%E2%80%98fish-deaths-over-years-expose-pollution-vashi-creek%E2%80%99
[2] http://admin.indiaenvironmentportal.org.in/category/author/sanjay-banerjee
[3] http://admin.indiaenvironmentportal.org.in/category/newspaper/times-india-navi-mumbai
[4] http://admin.indiaenvironmentportal.org.in/category/thesaurus/maharashtra
[5] http://admin.indiaenvironmentportal.org.in/category/thesaurus/river-pollution
[6] http://admin.indiaenvironmentportal.org.in/category/thesaurus/chemical-oxygen-demand-cod
[7] http://admin.indiaenvironmentportal.org.in/category/thesaurus/water-quality
[8] http://admin.indiaenvironmentportal.org.in/category/thesaurus/fish
[9] http://admin.indiaenvironmentportal.org.in/category/thesaurus/environmentalists
[10] http://admin.indiaenvironmentportal.org.in/category/thesaurus/water-pollution