Determination of the cyanide content in different water sources available to Dhaka

Abstract

Cyanide is known as one of the deadliest chemicals in the world and has a notorious history including mass genocide. There are very few antidotes against it which only work at a low concentration of the poison. High exposure to this chemical has no reversal and not only leaves permanent damage to the body but is also fatal at most of the times. With the growing number of industries in Dhaka city especially in the plastic, paint and metal sectors which have been known to release cyanide into the environment, there are higher chances of cyanide pollution now more than ever. My work focuses on the cyanide concentration in water bodies such as rivers and lakes which are a dumping ground for chemical wastes and also a comparison of other water available to the people living in the city. My work includes a survey of the areas that contain water bodies suspected with cyanide contamination. Samples were taken from these water sources such as the main water body of the area, tap water supplied into the area and the tube well water pumped from the ground. Water samples were also collected from non-industrial areas within Dhaka city for a better comparison. The water samples were then tested for cyanide in the laboratory following EPA guidelines and quantified. The results were then compared with WHO and US EPA guidelines for cyanide limit in drinking water. Results were compared with the location and type of the area within Dhaka city. Results proved cyanide concentration to be within limits but industrial areas’ to be very close to the borderline and at risk with the rapidly increasing number of industries every year