# Effects of Hematological Parameters and Plasma Components of Starry Flounder, Platichthys stellatus, by Waterborne Copper Exposure

## TL;DR

This study examines how copper exposure affects the blood and plasma of starry flounder, identifying key indicators of toxicity.

## Contribution

The study provides new insights into the physiological responses of starry flounder to acute copper exposure.

## Key findings

- The 96 h LC50 of copper for starry flounder was determined to be 15.644 mg Cu2+/L.
- Hemoglobin, hematocrit, and RBC count were significantly reduced by copper exposure.
- Plasma calcium, magnesium, glucose, AST, and ALT levels were significantly increased.

## Abstract

Copper is indiscriminately released into the natural environment through both natural processes and anthropogenic activities, posing a potential toxic threat to aquatic organisms. This study investigated the physiological effects of acute copper exposure over 96 h in starry flounder (Platichthys stellatus). The 96 h median lethal concentration (LC50) of copper in starry flounder exposed to high concentrations was determined to be 15.644 mg Cu2+/L, indicating the tolerance threshold to copper toxicity. Hematological parameters, including hemoglobin (Hb), hematocrit (Ht), and red blood cell (RBC) count, were significantly decreased. In contrast, plasma inorganic components (Ca, Mg), organic components (glucose), and enzymatic components (AST, ALT) were significantly increased. These findings suggest that the physiological responses of P. stellatus following acute copper exposure can serve as reliable standard indicators for assessing the tolerance limits of fish to copper toxicity.

Starry flounder (Platichthys stellatus) (weight 96.42 ± 19.17 g, length 20.65 ± 1.04 cm) were exposed to waterborne copper at 0, 0.5, 1, 3, 6, 12, 24, and 48 mg Cu2+/L for 96 h. The lethal concentration 50 (LC50) of the P. stellatus exposed to waterborne copper was 15.644 mg Cu2+/L. Hemoglobin, hematocrit, and RBC count were significantly decreased by waterborne copper exposure. MCV (mean corpuscular volume) (µL) and MCHC (mean corpuscular hemoglobin concentration) (%) were also significantly decreased. The inorganic components, plasma calcium, and plasma magnesium were significantly increased. The organic components, such as plasma glucose, were significantly increased. In enzymatic components, the AST and ALT were also significantly increased by copper exposure. The results of this study indicate that exposure to copper may have effects on the survival rates and hematological parameters of the P. stellatus.