Mercury is one of the least abundant elements in the earth’s crust. Mercury is a liquid metal found in natural deposits as ores containing other elements. This metal is used in electrical equipment and some water pumps. It usually gets into water as a result of improper waste disposal. Exposure at high levels may result in kidney disease or central nervous system problems .
Mercury can be found in water due to the erosion of natural deposits . Mercury contamination can also be the results of combustion of fossil fuels , metal smelters , cement manufacture, municipal landfills, sewage , metal refining operations, and most notably, from chloralkali plants. Electrical products such as dry-cell batteries, fluorescent light bulbs, switches , and other control equipment account for 50% of mercury use.
From 1987 to 1993, according to EPA’s Toxic Chemical Release Inventory, mercury releases to land and water totaled nearly 68,000 lbs. These releases were primarily from chemical and allied industries. The largest releases occurred in Tennessee and Louisiana .
How is it regulated?
Mercury is regulated as a primary standard under the EPA’s Safe Drinking Water Act as it is known to cause health effects. It is regulated at a level of 0.002 mg/L, which is also it’s MCLG which is the level at which no health effects are expected .
How is it tested?
Since mercury is a health-based contaminant you should have the water analyze using a laboratory. Laboratories analyzing drinking water samples can utilize various methods including EPA method 200 .7 and 200 .8 which use an Inductively Coupled Plasma (ICP) or EPA method 245.1 which uses cold vapor atomic absorption (CVAA) spectrometer system.
How do you treat for mercury?
Mercury is not commonly found in most drinking water sources, however is can be treated by Distillation or Reverse Osmosis for households.