The poorly defined “bioavailability” term was parameterized into three chemically defined exposure parameters, that can be measured by means of diffusive sampling techniques and that subsequently can be applied within the environmental risk assessment and management of chemicals and polluted sites. The three types of parameters are:
 
1. chemical activity, freely dissolved concentration or fugacity. These parameters quantify the potential of a chemical for spontaneous processes such as diffusion and partitioning.
2. accessibility, which describes the quantity of a chemical that is or can become available. It will always be operationally defined.
3. diffusive conductivity that characterises the diffusive property of an exposure media for a specific analyte.

1. Jahnke A, McLachlan M S, Mayer P (2008). Equilibrium Sampling: Partitioning of Polychlorinated Biphenyls (PCBs) and Selected Organochlorine Pesticides (OCPs) from Lipids into Polydimethyl-siloxane (PDMS). Chemosphere 73: 1575-1581.
2. Jahnke A, Mayer P, Broman D, McLachlan M S. (2009). Equilibrium sampling using polydimethylsiloxane in fish tissue – possibilities and limitations. Chemosphere 77: 764-770.
3. Legind C N, Karlson U, Burken J G, Reichenberg F, Mayer P (2007). Determining chemical activity of (semi)volatile compounds by headspace solid phase microextraction. Anal Chem 79: 2869-2876.
4. Magnér J A, Alsberg T E, Broman D (2009) Evaluation of poly(ethylene-co-vinyl actetate-co-carbon monoxide) and PDMS for equilibrium sampling of polar organic contaminants in water. Environ Toxicol and Chem 28: 1874-1880.
5. Magnér J, Alsberg T, Broman D. (2009), Bag-SPE—a convenient extraction method for screening of pharmaceutical residues in influent and effluent water from sewage treatment plants. Anal Bioanal Chemi, 395: 1481-1489.
6. Magnér J, Alsberg T, Broman D. (2009), The ability of a novel sorptive polymer to determine the freely dissolved fraction of polar organic compounds in the presence of fulvic acid or sediment., Anal Bioanal Chem 395: 1525 –1532.
7. Mayer P, Fernqvist M M, Christensen P S, Karlson U, Trapp S (2007). Enhanced diffusion of polycyclic hydrocarbons (PAHs) in artificial and natural aqueous solutions. Environ Sci Technol 41: 6148-6155.
8. Mayer P, Toräng L, Glæsner N, Jönnson J Å (2009). Silicone Membrane Equilibrator – measuring chemical activity of non-polar chemicals with PDMS micro-tubes immersed directly within tissue and lipids. Anal Chem 81: 1536-1542.
9. Mayer P, Karlson U, Christensen P S, Johnsen A R, Trapp S (2005) Quantifying the effect of medium composition on the diffusive mass transfer of hydrophobic organic chemicals through unstirred boundary layers.  Environ Sci Technol 39: 6123-6129.
10. Ossiander L, Reichenberg F, McLachlan M S, Mayer P (2008) Immersed Solid Phase Micro Extraction to measure chemical activity of lipophilic organics in fatty tissue samples. Chemosphere 71: 1502–1510.
11. Reichenberg F, Smedes F, Jönsson J Å, Mayer (2008) Vials with polymer coatings of multiple thicknesses for equilibrium sampling of hydrophobic organic compounds in soil. Chemi Centr J, 2: 8.
12. Reichenberg F, Mayer P (2006) Two complementary sides of bioavailability: accessibility and chemical activity of organic contaminants in sediments and soils. Environ Toxicol Chemi 25: 1239-1245.
13. Tian Y, Wang X R, et al. (2008). "Evaluation of Holistic Approaches to Predicting the Concentrations of Metals in Field-Cultivated Rice." Environ Science & Technology 42(20): 7649-7654.
14. Witt G, Liehr G A, Borck  D, Mayer P. (2009). Using solid phase microextraction to measure freely dissolved concentrations and chemical activities of PAHs in sediment cores of the western Baltic Sea. Chemosphere 74: 522-529.