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
Bioaccumulation out of natural chemical substances into the seafood or other organisms that will make-up eating organizations is a problem due to each other you’ll be able to adverse outcomes with the organisms on their own and the possibility of contact with predators, and people, that may consume such bacteria. The focus let me reveal for the bioaccumulation in the fish, however, equivalent principles connect with bioaccumulation in other aquatic drinking water-respiration organisms, and so they get affect sky-respiration organisms such wild birds and you will animals. This is why, a global step could have been released to check on commercial chemical substances for the capability to bioaccumulate step one, 2 . As an element of it initiative, several types of bioaccumulation investigation and metrics are used to influence whether and also to what extent chemical compounds was bioaccumulative. Comprehensive literature is present into the bioaccumulation of scientific and you may regulatory views, instances being the feedback because of the Barber step 3, cuatro , Mackay and you can Fraser 5 , Arnot and Gobas six , Ehrlich et al. 7 , Burkhard ainsi que al. 8 , and you may Gobas mais aussi al. nine , the second summarizing the newest conclusions off a great SETAC-backed workshop stored inside 2008. These or other ratings features discussed the presence of numerous metrics out-of bioaccumulation one differ into the definition, for the regulatory application, and in adoption because of the scientific people.
All of our objective we have found to establish and discuss the matchmaking between 5 common bioaccumulation metrics having aquatic organisms having a view so you can clarifying the cousin merits and you will usefulness getting bioaccumulation examination. We very first temporarily determine and you will talk about the bioaccumulation metrics, after that pertain a size harmony design to look at and you may quantify the matchmaking between the two. I seek to offer novel information into the root procedure resulting when you look at the bioaccumulation and gives advice having boosting and you can seeking analysis for bioaccumulation assessments.
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 wildbuddies 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.