Could you tell me about insecticides?

Chemical substances which are capable of killing almost all forms of living organisms in the fields of agriculture, forestry and household are biocides. These can be insecticides, fungicides, herbicides, nematicides, miticides, molluscicides, and rodenticides.

Insecticides are used against insects, their eggs and larvae found in agriculture, industry and household. Even though the insecticides have contributed towards agricultural revolution in the 20th century, these have altered our ecosystem and poisonous insecticide residues persist in food and drinking water. A balance between agricultural use and environmental health issues is very difficult to maintain. We must try it always with new ideas and more research.

There are various kinds of insecticides and they include:

• Organochlorines: DDT, aldrin, chlordane, endosulfan. endrin, dieldrin, heptachlor, lindane, pentachlorophenol and hexachlorobenzene. Mustard gas is used in the war as chemical weapon.

• Organophosphates: azinphos-methyl, chlorethoxyfos, dichlorvos, fenthion, malathion, mevinphos, parathion, parathionmethyl and tribuvos.

• Carbamates: used as insecticides, fungicides and herbicides in agriculture. Used against mosquitoes inside the buildings. These are aldicarb, carbofuran, carbaryl, methomyl and methyl carbamates.

• Pyrethroids: These are natural insecticides developed from the plant product (dried flowers) called pyrethrum. Permethrin, remethrin, cypermethrin, bifenthrin, tetramethrin, transfluthrin and many more belongs to this group and these are produced by adding chlorine, bromine, nitro group or others.

• Neonicotinoids: these are the synthetic analogue of natural nicotine. These are often used as substitutes for organophosphates and carbamates. These are clothianidin, nitenpyram, thiamethoxam, acetamiprid, clothianidin, nithiazine and thiacloprid.

The other plant products include caffeine, nicotine, and neem products. Insecticides are poisons and we must be very careful.

Iodine

Approximately 80% of iodine is found in our body is found in the thyroid gland. The thyroid gland is able to produce its hormones by using iodine. These hormones play a vital role in the growth and development of our body and also influence the maturation of our reproductive system.

Iodine is also important to our metabolic processes and helps to burn the excess calories. It keeps the skin, teeth, nails and hair to be strong and healthy. It helps to eliminate the toxins from the body and helps the body to use calcium and silicon. It is very useful in our body’s energy use.

Iodine deficiency can negatively affect the body and the mind.

Physical symptoms of iodine deficiency are skin problems, constipation, fatigue, goitre, weight gain, decreased fertility, increased stillbirth and growth abnormalities.

The mental symptoms of iodine deficiency are frustration, anxiety and depression.

The recommended daily intake of iodine is as follows:

AGE                              DAILY INTAKE [µg]

Infants:
0 to 12 months          50 - 80

Children:
1 to 3 years                 100
4 to 6 years                120
7 to 9 years                140
10 to 12 years                 180

Adolescents:
13 to 14 years            200
15 to 18 years            200

Adults:
Above 19 years         180

Pregnant:                 +30
Breastfeeding:      +60

The richest iodine source is kelp, a sea-weed. Sea fish is a very good source. Iodinated salt is also a reasonable source of iodine. Seafood, dairy products and eggs contain iodine.

The iodine deficiency in the developing foetus, babies and young children are serious. They include retarded growth and diminished intelligence. Iodine deficiency is a major problem in developing countries. This intellectual disability in children is preventable. Even a very mild deficiency may retard the brain development.

People in Western countries are not totally free from iodine deficiency. There are some western countries where the consumption of iodinated salts is still compulsory. There are also iodine deficient persons. Although iodine rich food is available to everybody in excess, they do not use it properly resulting in unhealthy thyroid.

The list of environment-related chemicals which affects thyroid glands is long. Some of the chemicals are insecticides, herbicides, polychlorinated biphenyls, dioxin, lead and aromatic hydrocarbons. By the way, cigarette smoke, active or passive, is also a risk factor for thyroid gland.