Maximum Contaminant Levels definition

Control of metalloid content in natural objects, foodstuff and pharmaceuticals is an important task for modern analytical chemistry. Determination of elements such as Arsenic is necessary for evaluation of object toxicity, since their content in environment may exceed MCL (maximum contaminant level), posing hazard to human health. Elements such as Selenium in definite doses are healthy, but in greater quantities they produce toxic effect. 

Central to the type of assessment is a definition of an environmentally acceptable concentration of each contaminant. These acceptable levels were defined as Maximum Permissible Concentrations (MPC), and were based on the toxicological assessments of solvents in drinking water by George and Siegel. These MPC levels (Table 17.2.1) are not the same levels as the current Maximum Contaminant Levels (MCL) that were promulgated by the U.S. Environmental Protection Agency for drinking water. 

The definition of water reference level or the level which triggers a report if found in surface or ground water, has been modified. The level depends on the levels established in section 304 of the Clean Water Act, the Maximum Contaminant Level (MCL) established by the EPA, the Health Advisory Level (HAL) or the lowest detectable limit depending on the chemical. 

IDLH Immediately Dangerous to Life and Health. The OSHA definition for IDLH is the maximum concentration of contaminant from which one can escape in 30 minutes without suffering irreversible health effects or escape-impairing effects such as dizziness, fatigue, impaired judgement, or slowing. Based on human and animal studies IDLH may be considered the LOEL (lowest observable effect level) or 500 x PEL if no other data are available or any concentration... 

The measures to be taken to ensure co-existence of GM and non GM farming - in order not to exceed the maximum level of GM contamination in food and feed -are by definition rather complex and more or less expensive depending on the respective crop, the relative share of GM plants in the region and specific farming situations. Therefore, for organic producers especially these measures are often perceived as economical threats for the following reasons ... 

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