Comparative Ecotoxicological Assay of E- waste (Phone Batteries) on Some Aquatic Micro Flora

摘要

Aim: To determine and compare the effect of used phone batteries on Nitrosomonas spp. in tri aquatic bodies Study Design: The study employs experimental design and statistical analysis of the data and interpretation. Place and Duration of Study: Freshwater and Marine samples were collected from Gokana L.G.A, while, a brackish water sample was collected from Eagle Island, all in Rivers state, Nigeria. These samples were transported with ice pack to the Microbiology laboratory of Rivers State University, Port Harcourt within 24 hours for microbiological and toxicity testing. The used phone batteries were purchased from the phone market, Garrison Junction, Port Harcourt. The toxicity testing was done for the duration of 4 hours interval for 24 hours respectively at room temperature. Methodology: Standard microbiological techniques were used; Toxicity testing procedures were carried out by preparing mobile phone batteries at concentrations of 0%, 5%, 25%, 50% and 75%, tested for durations of 0h, 4h, 8h, 12h and 24h respectively. The cultures were incubated at 35?C for 18 to 24 hours. LC₅₀ was determined using SPSS version 20. Results: The results indicate that percentage logarithm mortality of Nitrosomonas species increases with increased toxicants concentration and exposure time. The median lethal concentration (LC₅₀) of the mobile phone batteries increases in the following order: (Note: the higher the LC_50, the Lower the toxic effect; Nokia phone battery in marine water (65.97%) 50 = 64.13%) is the most toxic; having the lowest LC₅₀ while Nokia phone battery in marine water (LC₅₀= 65.97%) has the lowest toxicity effect. These results show that spent phone batteries can inhibit the nitrification process in aquatic ecosystem.