Herbicides and pesticides — and their toxic effects.

As a species we have become quite ingenious with respect to outwitting anything that threatens our food supply, whether it be insects, moulds, or overgrowth of weeds. It is generally believed that not only would our food supply be under threat, but without these harsh and very dangerous chemicals, our health may also be endangered. History shows that DDT suppressed a typhus epidemic in Naples in 1943-44, and more recently that a range of insecticides have been used to control malaria.

With regard to all chemical insecticides in use today, all of them are neurotoxic. Their properties affect the nerves and central nervous systems of pests and humans alike, the only difference being the relative doses ‘applied’.

Broadly speaking, herbicides are capable of killing plants.  Over the past 20 years or more, the herbicide business has grown rapidly, as a result of the need for more weed control. Gone are the days of crop rotation and fallowing, and the increased mechanisation and need for guaranteed yield has supported the industry’s growth. Although generally considered to be less toxic to humans than pesticides, there are concerns that herbicides and their manufacture may have carcinogenic effects, and may also result in foetal damage.

Fungicides are applied to plants and must be of low toxicity to the plant, whilst at the same time killing the fungus. Although relatively less toxic than pesticides, fungicides seem to demonstrate some ability to cause foetal damage, and a study of 11 fungicides suggest that they might account for 60% of the total estimated dietary carcinogenic risk.

Academic references