In the Andhra Pradesh part of the lagoon, several threats to the lagoon have been identified. These are: pollution from sewage, pesticides, agricultural chemicals and industrial effluents from Arani and Kalangi rivers draining into the lagoon bringing fertilizers and pesticides with the runoff from the agricultural field into the drainage basin; domestic sewage; effluents and wastes from numerous fish-processing units; oil spills from the mechanized boats. Release of of marine chemicals, and salt-manufacturing industry and shrimp farming in more than on the eastern part of the lagoon, have affected the Pulicat Bird Sanctuary; the livelihood of 30,000 fishermen and 20,000 agricultural labourers (for whom fishing is an off-season economic activity) have also been disturbed. This activity is also reported to have serious impact on aquaculture development.