Overview on management of Hazardous Waste in Singapore
United Nations Statistics Division
Patin says the composition of drilling fluids is so variable and the circumstances of their use so different that there is "an extremely wide range of concentrations that cause different toxic effects" ranging from "practical absence of toxic effects to lethal toxicity". He divides drilling fluid components into three main groups, based on their eco-toxicological hazard:
Environmental disasters - Lenntech - Water Treatment …
Patin says water-based drilling muds, while preferred over OBMs or SBMs for obvious environmental reasons, can still damage marine life. Leaving aside the question of toxicity, WBMs deposited on seabed sediments may smother benthic animals and, if in the form of very fine particles suspended in the water, can interfere with respiration in small marine animals and pelagic fish:
Ozone is a natural gas composed of three atoms of oxygen
This continued until the 1970s, with dumping at sea the accepted practise for disposal of nearly everything, including toxic material such as pesticides, chemical weapons, and radioactive waste.
Dumping of the most toxic materials was banned by the London Dumping Convention in 1972, and an amended treaty in 1996 (the London Convention) further restricted what could be dumped at sea.
It is blue in color and has a strong odor
However, there are still the problems of already-dumped toxic material, and even the disposal of permitted substances at sea can be a substantial environmental hazard.
Chemicals also enter the sea from land-based activities.