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
Introduction
Bioaccumulation from normal chemical compounds in the seafood or other bacteria that will constitute food stores is a concern on account of each other it is possible to bad consequences to your organisms on their own and prospect of exposure to predators, as well as individuals, which can eat these types of bacteria. The focus here is into the bioaccumulation in seafood, but comparable principles apply at bioaccumulation various other marine liquids-breathing organisms, and they also can get affect heavens-breathing bacteria like wild birds and you will animals. Because of this, a global effort might have been launched to check industrial chemical substances getting the capacity to bioaccumulate step one, dos . As an element of that it step, various kinds of bioaccumulation analysis and you will metrics are widely used to influence if or not and also to exactly what the quantity chemical try bioaccumulative. Comprehensive literary works is present to your bioaccumulation out-of medical and regulatory views, examples being the analysis of the Hairdresser step 3, cuatro , Mackay and you will Fraser 5 , Arnot and you can Gobas six , Ehrlich ainsi que al. 7 , Burkhard mais aussi al. 8 , and you will Gobas mais aussi al. nine , the latter summarizing new conclusions regarding a good SETAC-paid workshop stored during the 2008. russian brides These types of or any other studies have discussed the current presence of multiple metrics regarding bioaccumulation one to differ for the meaning, during the regulating software, and also in use because of the medical community.
Our goal the following is to establish and you may discuss the matchmaking between 5 preferred bioaccumulation metrics to have aquatic bacteria which have a standpoint in order to clarifying its cousin deserves and you may usefulness getting bioaccumulation examination. I earliest briefly determine and talk about the bioaccumulation metrics, following pertain a bulk equilibrium model to look at and you can measure the new relationship between the two. I seek to promote book facts to your underlying procedure resulting into the bioaccumulation and supply advice to possess improving and you will selecting analysis to possess bioaccumulation examination.
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.
