For example, the environmental half-life of 1,2-DCA from abiotic transformation in water was estimated to be 50 years ([Vogel et al., 1987]).
With the beginning of the 90s, various international commissions and North-American national institutions developed further the concept of environmental half-lives as persistence criteria and extended it to other environmental compartments (air, soil, sediment, ground water).
Their environmental half-lives can be expected to be shorter, and the fact that they have been part of the natural environment suggests a lesser demand for regulatory measures (Duke et al. 2000).
Arnot et al. [3] calibrated the models to empirical aerobic environmental half-life data from 40 selected "training set" chemicals and evaluated the outcome of this calibration with environmental aerobic biodegradation data of a set of 115 chemicals.
The purpose of this work was to identify a first design of a denitrifying urban NZW treatment process, operating at ambient temperature and pressure and circum-neutral pH, and providing mineralization of pharmaceuticals (not easily regulated in terms of environmental half-life), based on laboratory tests and mass balance and kinetic modeling.
He can sell out even an extremely market-friendly environmental half-step like Cap and Trade, but he never suggests that the cops start beating every longhair between Santa Barbara and Humboldt counties.
The environmental half-life of 131I, for example, is considerably shorter than its physical half-life because of physical and biological factors which may produce a half-life as short as 0.23/day.
This discrepancy may be explained by the longer environmental half-lives of dimethyl than diethyl OP pesticides or by alternate exposure pathways, such as diet and home pesticide use, which we have not explored here.
Tanks were drained and replaced with freshly treated water every 24 h (well within the 4.5-day environmental half-life of BPA, Cousins et al. 2002) and were scrubbed every 48 h to remove debris.
Because rotenone is believed to have a relatively short environmental half-life and limited bioavailability, a relationship to human disease has been questioned (Hatcher et al. 2008; Li et al. 2005).
In a recent Goucher poll, about two-thirds of those familiar with fracking for natural gas said the state should discourage it because of environmental concerns; half said it should be banned.
