Health Hazards of Pesticide

INTRODUCTION

This article will discuss about the harmful effects of pesticides (especially insecticides) use on human health. The pesticides applied to crops, household etc. are not only mitigating pest problem but they are also a source of extreme and permanent damage to human health and environment. 

Pesticides are substances or mixture of substances intended for preventing, destroying, repelling or mitigating any pest.

They include; 

1. Insecticides - kill insects
2. Fungicides - used to kill fungi
3. Biocides - used to kill microbes
4. Herbicides - used to kill herbs and weeds
5. Rodenticides - used against rodents e.g., rats.
6. Pediculicide [against lice (Pediculus humanus)] 
7. Fumigants etc.

ECONOMIC IMPORTANCE

• Used in agriculture, industry, household and medicine. 
• A major factor for rise in Agriculture productivity in 20th century. 
• Nearly all insecticides have the potential to significantly alter ecosystems; 
• Many are toxic to humans; others are concentrated in the food chain. 
• Uncertainty about Long term effects of low dose of pesticides. 
• Breathing disorders � asthma, leukemia 
• Neurological effects 
• Birth defects and fetal deaths 
• 25 million agriculture workers in developing countries suffer mild pesticide poisoning. � FAO 
• 3 million agriculture workers face serious poisoning. � FAO 

IMPACT ON HUMAN HEALTH

• Known or probable carcinogens 
• Hormone disruptors 
• Neurotoxins 
• Developmental or reproductive toxins

IMPACT OF THE PESTICIDE RESIDUES PRESENT IN AIR

People can be exposed to pesticides in three ways: 

  i. Breathing (inhalation exposure).

 ii. Getting it into the mouth or digestive tract (oral exposure).

iii. Contact with the skin or eyes (dermal exposure).

It depends upon 

 i. Length

ii. Magnitude of exposure

It can cause 

• Coughing 
• Irritation in skin 
• Lung damage 
• Worsens the bronchitis, emphysema, and asthma in people 
• Long-term exposure may scar the lungs. 
• Cancer 
• Hormone disruption in body

IMPACT OF THE PESTICIDE RESIDUES PRESENT IN SOIL

• Direct contact with soil or inhalation of soil contaminants when they vaporize.
• Greater threats when the contaminants are leached down to groundwater aquifiers which are source of drinking water. 
• Health consequences from exposure to soil contamination vary greatly depending on pollutant type pathway of attack and vulnerability of the exposed population. 
• Organophosphates and carbamates can induce a chain of responses leading to neuromuscular blockage. 
• Many chlorinated solvents induce liver changes, kidney changes and depression of the central nervous system.

PESTICIDES IN MILK

• Varying Concentrations of organochlorines have been found in cow milk.
• According to a research of The Chinese University of Hong Kong: �Most of the persistent organic pollutants (POPs) from DDT (dichlorodiphenyltrichloroethane) group were found in samples from human milk. 
• About 95% residues contain DDE (dichlorodiphenyltrichloroethane).