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Mathematical relationships between metrics regarding chemicals bioaccumulation for the fish

Mathematical relationships between metrics regarding chemicals bioaccumulation for the fish

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 off organic chemical substances into the seafood or any other organisms that can create dinner stores is a concern due to both it is possible to unfavorable consequences on the bacteria by themselves while the possibility of experience of predators, along with humans, that can consume such organisms. The main focus we have found into bioaccumulation within the fish, however, equivalent beliefs connect with bioaccumulation various other marine liquid-respiration bacteria, and in addition they could possibly get apply to sky-respiration organisms such as for example wild birds and animals. This is why, a global effort has been released to test industrial chemical to have the capability to bioaccumulate step 1, 2 . Included in this effort, several types of bioaccumulation investigation and you may metrics are used to influence if also to exactly what extent agents was bioaccumulative. Comprehensive literature is present into the bioaccumulation from medical and you can regulatory point of views, examples as being the ratings of the Barber step 3, 4 , Mackay and you can Fraser 5 , Arnot and you may Gobas six , Ehrlich ainsi que al. eight , Burkhard et al. 8 , and you will Gobas mais aussi al. nine , the latter summarizing this new results away from a beneficial SETAC-paid workshop stored from inside the 2008. These types of and other recommendations features mentioned the existence of numerous metrics away from bioaccumulation you to disagree during the definition, in regulating software, and in adoption of the medical society.

Our purpose let me reveal to identify and talk about the relationships ranging from 5 popular bioaccumulation metrics to have aquatic bacteria having a perspective to clarifying the cousin deserves and you can applicability to have bioaccumulation examination. I earliest briefly identify and discuss the bioaccumulation metrics, then apply a mass equilibrium design to look at and you can assess the latest relationship among them. I attempt to give book expertise towards the root process resulting for the bioaccumulation and gives suggestions to possess boosting and you may finding data to have 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 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.