API Publ 4656:1997 pdf download

API Publ 4656:1997 pdf download.BIOACCUMULATION: How CHEMICALS MoveE FROM THE WATER INTO FISH AND THER AQUATIC ORGANISMS.
Chemicals that have a propensity to concentrate in aquatic life to levels higher than those found in the ambient environment (water) are characterized as bioconcentratable or bioaccumulative substances- Bioaccumulation includes the uptake of chemicals from both water and diet whereas bioconcentration represents uptake from water alone. Even though many contaminants are often present in the environment only at trace (less than a part-per-million (ppm)] or ultra trace [less than a part-per-trillion (ppt)) levels, they can accumulate to toxicologically significant levels in the fatty tissues of exposed organisms. The driving force behind this bioaccumulation phenomenon is the propensity of many chemicals to have much higher solubilities in organism lipid (fat) than in the ambient water. Another way to view the bioaccumulation phenomenon is that lipid-loving (lipophilic) contaminants have much lower escaping tendencies (fugacities) from fatty tissues than from water.
Many industrial processes generate wastes with low levels of chemicals that may bioaccumulate. Because of the potential for trace concentrations of these chemicals to adversely affect ecosystems and human health, the U.S. Environmental Protection Agency (EPA) is in the process of drafting methods for the assessment of bloaccumulative substances in industrial effluents. To ensure that bioaccumulative chemicals are not present at unacceptable levels in industrial outfalls or effluents, industry needs to be knowledgeable on the physical-chemical properties that are characteflstic of these types of chemicals, how they interact with the environment, and the potential approaches available for their assessment.
This primer on bioaccumulahon. prepared under the direction of API’s Biomonitonng Task Force, is written for personnel with technical or scientific training, but without specific expertise in the subject matter. Afthough bioaccumulation is a complex subject, the authors have attempted to explain key aspects without using highly technical treatment of details. A glossary is Included to provide the reader with definitions of important terms related to bioaccumulation. Because several terms are defined only in the glossary and some variability exists in their use in the literature, reading the glossary is recommended. For example, in some literature bioaccumulation and bioconcentration are used mterchangeably.
Several classes of organic chemicals have the potential to bioconcentrate or bioaccumulate. Also, certain organometal complexes may bioconcentrate. The focus of this work is on the polycyclic aromatic hydrocarbons (PAHs), and in particular, the EPA pric,rity pollutanr PAHs. Energy production and use appear to be the primary sources of low levels of PAHs in the environment. The properties of a number of chlorinated hydrocarbons are also examined for comparative purposes. The organisms emphasized are aquatic but much of the information presented also applies to terrestrial life.