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SWAMP IQ Bioaccumulation

Quality Assurance & Quality Control Section
Data Management Section
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Additional Resources Section
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About Bioaccumulation

The term “bioaccumulation” refers to the uptake and accumulation of chemicals in an organism over time. Bioaccumulation occurs through respiration, ingestion, or direct contact with substance(s) and can result in organism tissue concentrations that are several orders of magnitude greater than the environmental concentration. This buildup occurs when chemicals are absorbed faster than they are excreted or metabolized. Bioaccumulation presents a risk to both the humans and wildlife that consume contaminated fish, as the toxins present in the fish tissue can be transferred to them, resulting in potential health problems.

qaqc image Quality Assurance and Quality Control

Answering any research question with a high degree of confidence requires high-quality data. Studies that produce low-quality data undermine project goals and can result in lost time and money. Therefore, it is crucial to ensure data usability through good quality assurance (QA) practices.

QA is comprised of an integrated system of management activities that are developed during the planning phase of a project. These activities are typically detailed in a QA plan that includes quality control (QC) requirements and corrective actions for field collections and laboratory analyses.

Sample Collection

In addition to fish, crustaceans and bivalves are frequently collected for analysis. Organisms are collected using a variety of devices, including trawl nets, gill nets, and electrofishing equipment. Each organism is measured, weighed, and assigned a unique identification number. The latitude and longitude of the area in which the organism was caught is also recorded before the sample is preserved on ice.

Tissue Composites

Once fish are collected for a given bioaccumulation study, they are composited to include a uniform quantity of tissue from the species of interest. These homogenized samples, consisting of at least three fish, are then analyzed as individual samples in order to provide a measure of average chemical concentrations at a reduced cost. Projects adhere to the “75 percent rule” which requires that the length of the smallest fish in a sample be at least 75 percent of the length of the largest fish in that sample.

Tissue Chemistry

Bioaccumulation studies analyze a variety of chemicals, ranging from metals such as methylmercury, to organics such as polychlorinated biphenyls (PCB). For information about the QA/QC procedures for these analytical methods, please visit the SWAMP chemistry data webpage.

data mngmt image Data Management

Data management is another vital component of ambient monitoring that incorporates QA measures such as uniform business rules and data review. These strategies ensure the usability of the data generated for a project.

Business Rules

Standardized language and formatting promotes consistency and prevents the misinterpretation of data. Business rules establish a uniform method of data entry that enables both project staff and end users to easily understand test results.

Data Review

Data should be reviewed by all applicable project staff, beginning with the field crew and laboratory data managers, and ending with the project managers and QA officers. This verification process ensures that sample collection details, such as the date, time, and location of the event are recorded in the proper format. Data reviewers also confirm that test QC measures, such as matrix spikes and laboratory duplicates, are acceptable for a given method. In addition to examining these elements, reviewers confirm that all appropriate business rules have been followed.

Water Board Databases

The Water Boards utilize various databases to store a large quantity of information about water quality above and below ground. Summaries and links to these databases are provided below.

Measurement Quality Objectives

In an effort to promote precision and reduce bias, SWAMP has established field and laboratory guidelines for various analytes. Dubbed “Measurement Quality Objectives (MQO),” these guidelines contain both recommendations and requirements for sample collection and laboratory analyses.

swamp resources us image SWAMP Resources

people holding up fish

addl resources image Additional Resources

Bioaccumulation Oversight Group (BOG) – BOG, a workgroup of the California Water Quality Monitoring Council, was created to assess the impacts of contaminants in fish and shellfish in water bodies throughout the state. In addition to conducting bioaccumulation research and synthesizing data from other studies, BOG manages the Safe to Eat Portal and a forum for coordinating bioaccumulation monitoring. These studies and resources can be accessed on the BOG webpage.

contact us image Contact Us

For questions regarding these data types, please contact:

Tissue Composite Data and Tissue Analyses

Tissue Chemistry Data

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Please send comments and suggestions to the Office of Information Management and Analysis Help Desk: OIMA-Helpdesk@waterboards.ca.gov

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SWAMP Bioaccumulation Partners

California Department of Fish and Wildlife
Moss Landing Marine Laboratories