ACUTE TOXICITY AND BIOACCUMULATION OF LEAD IN THE SNAIL, FILOPALUDINA (SIAMOPALUDINA) MARTENSI MARTENSI (FRAUENFELDT)

Abstract

Acute lead toxicity studies were carried out in the snails, Filopaludina (Siamopaludina) martensi martensi (Frauenfeldt). The 96-hour static bioassay was conducted in order to estimate the median lethal concentration (LC50). The snails were exposed to lead nitrate [Pb(No3)2]. The LC50 for 24, 48, 72 and 96 hours were 519-47, 271.03, 235.35 and 191.69 mg/l, respectively. The percentage mortality of these snails increased with increasing concentration and exposure time. In the bioaccumulation experiment, the snails were exposed to 19-17 mg/l (10% 96-hour LC50) of lead nitrate for 42 days exposure time and 30 days recovery time. During the 42-day exposure period, lead uptake occurred in different organs with the greatest uptake in the intestine, and less in the prostate gland, digestive gland, ovary and albumen gland, testis, stomach and cerebral ganglia. After exposure, lead concentration in all organs decreased during the 30 day recovery period.