1991/2 – Records of Fish Kills in Inland Waters of NSW and Qld in Relation to Cotton Pesticides. Fish kills associated with insecticide Endosulfan used primarily on cotton crops. Endosulfan recorded in Gil Gil Creek at Galloway at 0.8ug/L. Source: Wetlands Australia 1998.

https://ojs.library.unsw.edu.au/index.php/wetlands/article/viewFile/192/198

In1984, sampling by the NSW State Pollution Control Commission in response to a major fish kill, identified endosulfan residues in Gil Gil Creek, north west of Moree at levels of (0.9-1.5ug/L) well above the LC50 for trout (0.3ug/L). Follow up sampling of Boobera Lagoon in the MacIntyre Valley during 1983-1984 confirmed the presence of endosulfan and a report on pesticide monitoring from the central and north west regions in 1995, acknowledged that the detection of high levels of endosulfan residues in the environment was a consequence of its use in agriculture. In the 1989-99 sampling in the Murray Darling Basin, endosulfan was detected in 53% if water samples with the median levels ranging from 0.02ug/L to 0.04ug/L.

https://ntn.org.au/wp/wp-content/uploads/2010/02/polluterpaysmythlegend.pdf