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 regarding organic toxins during the seafood and other bacteria that make-up restaurants organizations is a concern due to one another it is possible to negative effects towards bacteria on their own as well as the prospect of experience of predators, along with human beings, that eat these types of organisms. The main focus listed here is into the bioaccumulation from inside the seafood, but equivalent prices apply at bioaccumulation various other marine drinking water-breathing organisms, and in addition they get connect with sky-respiration organisms such as for instance birds and animals. This is why, a major international initiative could have been launched to evaluate industrial chemical to have the power to bioaccumulate firstmet profile examples 1, 2 . Included in which step, distinct bioaccumulation analysis and you may metrics are acclimatized to dictate whether in order to what the total amount toxins was bioaccumulative. Extensive books is obtainable into the bioaccumulation off scientific and you may regulatory point of views, advice being the ratings by the Hairdresser step three, cuatro , Mackay and you may Fraser 5 , Arnot and Gobas six , Ehrlich et al. seven , Burkhard mais aussi al. 8 , and you may Gobas et al. 9 , the second summarizing the new results away from a good SETAC-paid workshop stored in the 2008. Such or any other analysis features discussed the current presence of numerous metrics away from bioaccumulation that disagree when you look at the meaning, in regulatory software, and in adoption from the medical area.
All of our objective is to determine and you can discuss the relationship ranging from 5 preferred bioaccumulation metrics getting marine bacteria having a standpoint so you’re able to clarifying its relative merits and you will usefulness to own bioaccumulation tests. I basic briefly describe and you will discuss the bioaccumulation metrics, after that use a bulk harmony design to look at and quantify the new matchmaking between the two. I attempt to give novel wisdom with the root processes ensuing in the bioaccumulation and supply suggestions getting improving and you may shopping for investigation getting bioaccumulation tests.
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.