When toxic chemicals refuse to die - An examination of the prolonged mercury pesticide use in Australia

Mercury, even in low concentrations, is known to cause severe adverse human health effects. In the early 1900s, mercury became a popular fungicide ingredient, leading to multiple poisoning incidents that forced much of the world to act upon phasing out mercury use in agriculture. These incidents spurred the advancement of mercury science and the implementation of international policies and regulations to control mercury pollution worldwide. Despite these developments internationally, Australia continued using methoxyethyl mercury chloride as a fungicide to treat sugarcane against the fungi Ceratocystis paradoxa (pineapple disease). At the request of the manufacturer and following pressure from Australian researchers and the Minamata Convention on Mercury, Australian authorities announced a ban on mercury-containing pesticide in May 2020. Australia’s unique reluctance to act on controlling this hazardous pollutant makes it an interesting case study for policy inaction that runs counter to global policy trends and evidence-based decision making. As such, it can provide insights into the challenges of achieving multilateral agreement on difficult environmental issues such as global warming. In this review, I discuss the scientific development and policy decisions related to mercury fates and exposure of wildlife and humans in Australia to mercury used in pesticide. The historical uses of mercury pesticide and poisoning incidents worldwide are described to contextualize Australia’s delayed action on banning and controlling this chemical product compared to other nations. Regulations on mercury use in Australia, which has not ratified the Minamata Convention on mercury, are compared to those of major sugarcane and pesticide producer nations (Brazil, China, Japan, India, Thailand, and United States) which have ratified the Convention and replaced mercury pesticides with alternative products. I discuss how mercury regulations have the potential to protect the environment, decrease human exposure to mercury, and safeguard the ban on mercury products. Ratifying the Minamata Convention would give Australia equal footing with its international counterparts in global efforts to control global mercury pollution.