Toxicity of Lead to Freshwater Invertebrates (Water fleas; Daphnia magna and Cyclop sp) in Fish Ponds in a Tropical Floodplain

Abstract

Acute toxicity of Pb to the water flea; (Daphnia sp) and Copepod, (Cyclop sp) both important component of zooplankton diet of fish was determined by static assay. A positive relationship between percentage mortality and exposure concentration was found in all tests. Mean 24-h LC50, 48-h LC50 and 96-h LC50 values were 2.51±0.0.04 mg l −1 , 1.88± 0.06 mg l −1 and 1.65±0.19 mg l −1 for Daphnia spp and 3.11±0.03 mg l −1 , 2.97±0.05 mg l −1 and 2.61± 0.09 mg l −1 for Cyclop spp, respectively. For all tested species did the LC50 values decrease with time; the decrease was more marked for Daphnia spp. Observed symptoms include spiral movement followed by change of body colour to white and rapid disintegration of the skin. The Daphnia spp. appear to be more sensitive to Pb poison than Cyclop spp. The results showed that concentrations of Lead (Pb) in excess of 0.19 mg l −1 and 0.30 mg l −1 can be potentially harmful to Daphnia magna and Cyclop spp respectively.

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“…Between the green algae biomass in the Shardara reservoir and zinc, we found a statistically significant positive relat ionship (Krupa et al, 2017), wh ich may be due to the stimulat ing effect of low concentrations of zinc on phytoplankton (Cao et al, 2015). Lethal concentration of lead to cladocerans are two orders of magnitude higher (more than 3.0 mg L -1 ) (Garcı´a-Ga rcı´ et al, 2006), and potentially dangerous concentration -one order of magnitude higher (0.19 mg L -1 ) (Offem & Ayotunde, 2008) than the amount of lead in water of the Shardara reservoir (0.034 mg L -1 ). Quantitative parameters of Copepoda, formed mainly by cyclops Acanthocyclops trajani, were negatively affected by organic polyphosphates, nitrates and total nitrogen.…”

“…With escalation of pollution, Cladocera disappears first from the community (Gagneten & Paggi, 2009). Rotifera and Cyclopoida are more adapted to the conditions of polluted water (Offem & Ayotunde, 2008;Xu et al, 2014).…”

Determination of toxic heavy metal levels in commonly consumed species of shrimp and shellfish using ICP-MS/OES

“…Several possible explanations can account for variations in metal accumulations in tissues. Metabolic rates of organisms, exposure routes, metal mobility values, bioavailability, chelators present in water, and time spent in contaminated water are among important contributing factors (16)(17)(18)(19). In addition, the environmental factors of pH, temperature, salinity, nutrients, organic matter, organic carbon, and Recovery result for spiking (mean value of 5 determinations)…”

Dynamics of the limnological features and diversity of zooplankton populations of the Cross River System SE Nigeria

“…Results have showed that concentrations of lead (Pb) in excess of 0.19 mg·L -1 and 0.30 mg·L -1 can be potentially harmful to Daphnia magna and Cyclop spp. respectively (Offem et al, 2008). Cadmium has long biological life of about 20-30 years.…”