Five widely used metrics of bioaccumulation in fish are defined and discussed, namely the octanol–water partition coefficient (KOW), bioconcentration factor (BCF), bioaccumulation factor (BAF), biomagnification factor (BMF), and trophic magnification factor (TMF). Algebraic relationships between these metrics are developed and discussed using conventional expressions for chemical uptake from water and food and 
first-order losses by respiration, egestion, biotransformation, and growth dilution. Two BCFs ely as an equilibrium partition coefficient KFW or as a nonequilibrium BCFK in which egestion losses are included. Bioaccumulation factors are shown to be the product of the BCFK and a ely, the diet-to-water concentration ratio and the ratio of uptake rate constants for respiration and dietary uptake. Biomagnification factors are shown to be proportional to the lipid-normalized ratio of the predator/prey values of BCFK and the ratio of the equilibrium multipliers. Relationships with TMFs are also discussed. The effects of chemical hydrophobicity, biotransformation, and growth are evaluated by applying the relationships to a range of illustrative chemicals of varying KOW in a linear 4-trophic-level food web with typical values for uptake and loss rate constants. The roles of respiratory and dietary intakes are demonstrated, and even slow rates of biotransformation and growth can significantly affect bioaccumulation. The BCFKs and the values of M can be regarded as the fundamental determinants of bioaccumulation and biomagnification in aquatic food webs. Analyzing data from food webs can be enhanced by plotting logarithmic lipid-normalized concentrations or fugacities as a linear function of trophic level to deduce TMFs. Implications for determining bioaccumulation by laboratory tests for regulatory purposes are discussed. Environ Toxicol Chem 2013;–1466. © 2013 SETAC
Inclusion
Bioaccumulation of natural agents inside fish or any other organisms that may constitute eating stores is a problem because of both you are able to adverse effects to the bacteria themselves in addition to prospect of connection with predators, in addition to humans, that may eat these organisms. The main focus we have found toward bioaccumulation when you look at the seafood, however, equivalent beliefs connect with bioaccumulation various other aquatic water-respiration bacteria, and so they can get apply at air-breathing bacteria such as for example wild birds and you will mammals. Because of this, an international step has been introduced to check on industrial chemical compounds to own its power to bioaccumulate 1, 2 . Included in that it effort, various kinds of bioaccumulation analysis and metrics are used to influence whether or not and to just what the amount chemical compounds is actually bioaccumulative. Thorough literary works can be acquired on the bioaccumulation out-of scientific and you will regulatory views, examples as being the studies from the Hairdresser step 3, cuatro , Mackay and you may Fraser 5 , Arnot and you can Gobas 6 , Ehrlich et al. 7 , Burkhard mais aussi al. 8 , and you may Gobas ainsi que al. 9 , aforementioned summarizing the brand new results away from a great SETAC-sponsored working area kept in the 2008. These or any other recommendations has pointed out the clear presence of several metrics out of bioaccumulation one to disagree in the definition, inside the regulatory application, and also in adoption from the medical people.
Our very own mission here’s in order to describe and you can talk about the dating ranging from 5 well-known bioaccumulation metrics for aquatic bacteria which have a standpoint in order to clarifying their relative merits and applicability to have bioaccumulation tests. We earliest briefly identify and talk about the bioaccumulation metrics, upcoming pertain a size balance model to examine and you will measure the new relationships between the two. I seek to give novel understanding into hidden process ensuing during the bioaccumulation and supply pointers getting improving and you will finding studies to have bioaccumulation assessments.
BIOACCUMULATION METRICS
For the current analysis, we define and describe 5 common metrics for assessing bioaccumulation. Differences exist in the definitions and usage of these terms; however, the definitions given here are used to develop mathematical relationships in the next section. The octanol–water partition coefficient (KOW) is widely used as an indicator of hydrophobicity and thus the partitioning of a chemical from water into lipids and other organic phases such as protein 10 . The KOW is primarily controlled by the solubility of the substance in water, because the solubility of neutral, liquid nonpolar organic chemicals in octanol is relatively constant. A log KOW value of 5 is often used as a bioaccumulation assessment criterion; however, depending on the regulatory program, lower values are also used to categorize bioaccumulation potential. Whereas KOW gives a reasonable and conservative estimate of lipid–water partitioning for nonpolar hydrophobic substances 11 , it may not accurately simulate partitioning for more polar and ionogenic organic chemicals and other chemical classes such as organofluorines and silicones. Direct empirical measurement is essential in such cases.
