Lead In Fish Research Articles

Accumulation of lead in fish from Missouri streams impacted by lead mining.

This study was conducted to determine if elevated levels of lead occur in the edible tissue of fish inhabiting Missouri streams affected by lead mining.

Use of Blood Lead and Erythrocyte θ-Amino Levulinic Acid Dehydratase Activity to Detect Lead Exposure of Fish Populations

The measurement of blood lead concentrations and inhibition of erythrocyte θ-amino levulinic acid dehydratase activity (ALA-D) has been used successfully to diagnose lead exposure in human populations. While blood lead is one of the best indicators of lead exposure, its measurement is expensive, time consuming, subject to bias through contamination and requires highly skilled personnel. The advantages of assaying ALA-D activity are those of cost, speed, sample size and simplicity. Since most organisms possess this enzyme in a variety of tissues, and since its activity is inhibited only by lead, there is potentially a large variety of aquatic species that may be used to monitor “biologically available” lead in aquatic ecosystems. Sessile and migratory species could integrate short-term fluctuations in waterborne lead and provide data on spatial and temporal variations. Fish are convenient organisms to sample and fish blood is a particularly rich source of ALA-D. Laboratory experiments have defined the optimum conditions for blood sampling and assaying ALA-D activity as well as the strong negative correlation between blood lead concentrations and ALA-D activity and between waterborne lead concentrations and ALA-D activity. Other toxic metals (e.g. Cu, Hg, Zn, Cd) and PCB's do not inhibit ALA-D, and factors that increase lead toxicity (e.g. decreased environmental pH) also increase lead uptake and the inhibition of ALA-D. Consequently, ALA-D activity provides a measure of both exposure and effect. Species variation in rates of lead uptake allows a selection of a suitable monitoring species for a given, situation. Preliminary surveys of Lake Ontario fish populations indicate that monitoring of ALA-D activity is technically simple and straightforward, the assay is much cheaper and faster than blood lead or whole body lead analyses, and activity is correlated to other measures of lead in fish.

Determination of lead in fish by furnace atomic absorption.

Determination of lead in fish by furnace atomic absorption.

Determination of Lead in Fish by Atomic Absorption Spectrophotometry and by Polarography. I. Development of the Methods

Abstract A method for the determination of lead in fish by atomic absorption spectrophotometry and polarography is described. The samples were dry-ashed at 500°C and dissolved in IN HC1; lead was determined by either method. Good agreement between atomic absorption spectrophotometry and polarography was obtained at levels of 1.0 to 10.0 ppm. Over this range the recoveries averaged 96.1% for polarography and 93.8% for atomic absorption spectrophotometry. Twelve species of fresh and salt water fish were analyzed.

Determination of Lead in Fish by Atomic Absorption Spectrophotometry and by Polarography. II. Collaborative Study

Abstract Nineteen laboratories, using 6 different models of atomic absorption spectrophotometers and 4 different types of polarographs, participated in this collaborative study. The average lead recoveries from 6 paired samples at 1–2, 5–6, and 10–11 ppm levels were 97.7% by polarography and 100.7% by atomic absorption. The average standard deviations were 0.32 and 0.41 ppm, respectively, and the average coefficients of variation were 7.9 and 13.1%, respectively. With collaborators reporting on both methods, the results of the overall method average were 4.3 ppm for polarography and 4.4 ppm for atomic absorption. Since there were no significant differences (p > 0.05) found between the method averages, except at one of the unspiked levels, the 2 methods can be used to confirm each other at levels of 1-11 ppm. The polarographic method has been adopted as official first action for the determination of lead in fish.