In the process of seed germination, all kinds of stored substance (mainly in the endosperm) are broken down into a variety of small molecules, thus providing the respiration substrates as well as substance transformation and synthesis and a number of raw materials to form the new cells.
In addition, we recommend treating the input of water on a net basis, that is, to exclude all once-through water uses such as for washing equipment and to include only water that is associated with substance transformations.
The combined effects of all leachable substances and transformation products are determined by their total effects in bioassays.
Complex mixtures of priority pollutants and emerging substances [5], transformation products [6] and natural compounds occur in aquatic systems, and the possibility to assess their combined effects is still limited [7 9].
However, for new (emerging) anthropogenic substances and transformation products of known chemicals, these strategies would not work so well as they would have neither a high reference count nor a low database identifier.
Therefore, using a reference substance for transformation studies seems necessary.
Besides the known compounds, a wide range of anthropogenic organic substances and their transformation products occur in the aquatic environment.
Determination and assessment of the characteristics of site-specific flowback, with regard to constituents of relevance to drinking water quality (salts, heavy metals, NORM, hydrocarbons), and with regard to additives used (primary substances) and their transformation products (secondary substances); determination and assessment of the proportion of fracking fluids recovered with the flowback.
Little is known about the environmental or human health hazards that might be posed by chronic, subtherapeutic levels of these bioactive substances or their transformation products.
