Question

State 2 incidence of mass poisoning of humans that involved arsenic. What are some of the uses of mercury and what is the aspects bioaccumulation of mercury?

Answer 1

Incidences of mass poisoning of humans that involved arsenic:

The most well- known incidence of mass poisoning fo arsenic is that of Bangladesh. Thousands of wells dug in the 1970s in Bangladesh in attempt to provide clean drinking water were over time contamination with arsenic. Almost half of the Bangladeshi population is exposed to this poisoning.

Another instance of mass poisoning due to arsenic is that of the north-eastern part of India, including the states of Manipur, Arunachal Pradesh, Assam, West Bengal, Bihar, Jharkhand, Chhattisgarh, Bihar and Uttar Pradesh.

There is also an instance in 1858 England, where 200 people were poisoned due to sweets supposedly poisoned accidentally. 21 of these affected people died.

Uses of mercury:

1. As catalyst in metallurgy and chemical industries.

2. In electrical switched and rectifiers.

3. As an amalgam with gold, silver and tin, for dental fillings.

4. In paints, as bright-red pigment.

5. Most popularly used in thermometers.

Aspects of bioaccumulation of mercury:

Most of the mercury in the atmosphere finds its way in the living body through water. Most of the mercury discharged in industrial effluents ends up in water-bodies, wherein bacteria play a major role in converting ti into methylmercury. This bacterial conversion i s a major pathway for entry of mercury into the food chain. methylmercury is more toxic than mercury because the living body can easily absorb the this form of mercury. This causes bioaccumulation of mercury. Organisms exposed to it build up the level of mercury within their body and pass it to those who thrive on them. This leads to biomagnification of mercury.