Mercury (element) and galinstan alloy thermometers are also an option. Mercury thermometers are still occasionally used in the medical field because they are more accurate than alcohol thermometers, though both are commonly being replaced by electronic thermometers and less commonly by galinstan thermometers. Mercury thermometers are still widely used for certain scientific applications because of their greater accuracy and working range. Historically, one of the largest releases was from the Colex plant, a lithium-isotope separation plant at Oak Ridge, Tennessee. The plant operated in the 1950s and 1960s. Records are incomplete and unclear, but government commissions have estimated that some two million
The Broads practices and sewage disposal in the 1950s and 1960s released high levels of phosphorus and nitrogen into the Broads, causing eutrophication. Algal blooms can be toxic, posing a health risk to humans and wildlife. Mass decay of plant matter removes oxygen, damaging fish stocks, preventing recreational fishing. The loss of larger plants and reed fringes in eutrophic waters increases erosion of banks and the buildup of sediment on lake floors. This impedes navigation and requires costly dredging to remove. The beauty of the area is damaged by eutrophication, which is detrimental to the tourism industry. The Broads authority and Environment