Toxicological Effects of Some Heavy Metal Ions on Culex pipiens L. (Diptera: Culicidae)

Abstract

Different concentrations of selected heavy metals in the form of cadmium chloride (CdCl 2), copper sulphate (CuSO 4), lead nitrate (Pb (NO 3) 2) and mercuric nitrate (Hg (NO 3) 2) were tested against immature and mature stage of C. pipiens to assess the toxicity, LC 50 , total carbohydrate and lipid content. The survival potential of 2 nd instar larvae was highly affected by the contamination with the tested heavy metals. On the basis of LC 50 , Cd was the most toxic metal against the larval stage followed by Hg, Cu and Pb. The late toxicity of heavy metals tested on the adult females resulted from larvae treated with the LC 50 of each heavy metal decreased significantly the number of eggs laid by female. The fecundity recorded 81.7±5.03, 90.3±2.52, 92.7±3.5 and 78.6±1.52 eggs/♀ for females resulted from larvae treated with the LC 50 of CdCl 2 , CuSO 4 , Pb (NO 3) 2 and Hg (NO 3) 2 ; respectively, compared to 186±4 eggs/♀ for control females. The hatchability percent of eggs laid with the LC 50 of CdCl 2 , CuSO 4 , Pb(NO 3) 2 and Hg (NO 3) 2 was significantly decreased to 37, 73, 80 and 39 %; respectively, compared to 97 % for eggs laid by untreated females. A significant decrease in total carbohydrate content in the whole body of males and females, C. pipiens resulted from larvae treated with the LC 50 of CdCl 2 or the LC 50 of Hg (NO 3) 2 was observed. Also, the present study showed a significant decrease in total lipid content of females by the LC 50 CuSO 4 and the LC 50 of Hg (NO 3) 2 , while in males a significant increased was caused by the LC 50 CuSO 4 and the LC 50 of Pb(NO 3) 2. It is clear from the results obtained in this study that the presence of such elements in the environmental system of the mosquito C. pipiens water as possible to contribute to the reduction of mosquito breeding.

Short-Term Biochemical Impacts in <i>Cyphoderus javanus</i> Borner (Collembola) as Potential Biomarkers of Fly Ash and Heavy Metal Pollution in Tropical Lateritic Soil

“…Another study showed that exposure to Cd treated soil produced destruction of mitochondria and microvilli border of cells in the digestive tract of Proisotoma minuta (Collembola) [35]. Some other corroboratory results on the ill effect of heavy metals on food uptake and assimilation, and tissue nutrient profile are in Isopoda Porcellio laevis [36], in Diptera Boettcherisca peregrine [37], and in mosquito Culex pipiens [38]. Most metals disrupt the enzyme functions by binding with sulphur groups in enzymes, and inhibition of enzymes may be due to the making of catalytically active groups or by protein denaturation [39].…”

Effect of Cadmium and Lead on Total Hemocyte Count of Achroia grisella Fabr. (Lepidoptera: Pyralidae)

“…Invertebrates are good models to study toxicity of heavy metals and are useful bioindicators of contamination of the environment (Borowska and Pyza, 2011). Previous studies showed that toxicity of heavy metals on immune cells are related to the species, dose, the method of application, developmental stage of animals and animal's sensitivity (Kazimírová and Slovák, 1996;El-Sheikh et al, 2010;Suganya et al, 2016). Here, we tested the heavy metal toxicity at cellular levels and examined the lesser wax moth's hemocytes as an element of its immune system.…”

“…They observed that Cd and Pb metals are toxic on S. litura larvae and cause strong oxidative stres. In another study El-Sheikh et al (2010) proved that the larval mortality percent of Culex pipiens L. (Diptera: Culicidae) larvae increased as the concentration of heavy metals namely; Cd, Cu, Pb and mercury (Hg) increased. In addition, Bischof (1995) reported that different types of metals significantly affects the biochemical composition of parasitized Lymantria dispar (Lepidoptera: Lymantriidae) larvae.…”

“…Heavy metal pollution in air and water has been associated with various negative effects on insects (Borowska et al, 2004;El-Sheikh et al, 2010;Suganya et al, 2016). Borowska et al (2004) showed that rearing Musca domestica (Diptera: Muscidae) larvae on an artificial media contaminated with copper (Cu), zinc (Zn), lead (Pb) and cadmium (Cd) resulted in their accumulation in the body and this accumulation disturbed the larval development and the survival rate of larvae and pupae.…”

Ovicidal, pupicidal and bactericidal effects of aminopyridinium-based ionic liquids onCulex pipiensand certain human pathogenic bacteria

“…El-Sheikh et al [82] studied the effect of different concentrations of selected heavy metals' salts against immature and mature stages of C. pipiens and they found that the potential survival of second instar larvae was highly affected by these salts. The number of eggs laid by females resulted from treated larvae decreased significantly and therefore, a lower fecundity was recorded for these females compared with control mosquitoes.…”