首页>
外文期刊>Environmental Science & Technology: ES&T
>A new approach suggests that phenomena, such as bioconcentration, biomagnification, and bioaccumulation, result from two fundamental processes
【24h】
A new approach suggests that phenomena, such as bioconcentration, biomagnification, and bioaccumulation, result from two fundamental processes
展开▼
机译：A new approach suggests that phenomena, such as bioconcentration, biomagnification, and bioaccumulation, result from two fundamental processes
As we view the behavior of contaminants in the environment, the question comes to mind: Why are certain contaminant concentrations "amplified" to unusually high levels in certain environmental media, such as lipids and aerosol particles, and in certain locations, such as high- altitude lakes? This is obviously of concern because high concentrations can lead to greater exposures and amplified effects on organisms. Effective management of commercial chemicals and those produced inadvertently; especially those that are persistent, bioaccumulative, and toxic (PBT), requires that we fully understand the fundamental mechanisms causing concentration amplification. This understanding can lead to predictive and then preventive strategies. Wania discussed aspects of this issue in a pioneering study and suggested three fundamental causes: equilibrium partitioning, kinetic effects, and changes in phase composition, volume, or temperature (1). Here, we take a somewhat different approach and suggest that there are only two basic and quite distinct processes or operations, which we term "solvent switching" and "solvent depletion". These, in turn, can cause two effects: concentration amplification and fugacity amplification. In the environment, these processes can occur singly or in combination. Discriminating between the two effects clarifies the fundamental causes of high contaminant concentrations, contributes to a fuller understanding of the fate of chemicals in the environment, and may help to anticipate how global change operates on contaminants. We also suggest that under certain transient or dynamic conditions, a "filtering" effect may cause high concentrations. In this feature, we introduce and illustrate these concepts using an example drawn from analytical chemistry and then discuss a number of natural environmental phenomena.
展开▼
