Wednesday, April 2, 2014

Effects of pesticides - Necessity of Safe Agro Products


  • With the increase rate of productivity by our farmers, most of them with inadequate knowledge in farming, using unnecessary and excessive dosages even also low grade of pesticides containing harmful elements for human and eco-system. The cropping intensity and high yield variety (HYV) of crops have necessitated more use of pesticides. Though production increased tremendously ensuring food security but second generation problems started pouring. 
  • Pests take a heavy toll on food production in Bangladesh. To control the pets and diseases during production level, farmers increasingly use chemical pesticides. Over the past 15 years, pesticide consumption has increased substantially, from 1,695 metric tons in 1995 to 41,791 metric tons in 2009. Yearly increase of pesticides use around 1- 2%. Use of pesticides in vegetable farms is higher and frequent.
  • Most of the farmers knew the importance of taking protective measure during pesticides application. But, 85-90% of farmers were not accustomed to take any protection during pesticide application as well as preservation and transportation. Selection of pesticide, dosage and mode of application were based on agro-chemicals dealers’ suggestion and forceful marketing campaigns by pesticide producing countries and importers in Bangladesh. While pesticides may temporarily prevent, control or kills pests, their prolonged and intensive use has profoundly negative impacts.
  • The World Health Organization and the United Nations Environment Program estimate pesticides poisoning rates of 2-3 per minute, with approximately 20,000 workers dying from exposure every year, the majority in developing countries (WHO, 1990; Kishi et al., 1995). Intentional and unintentional pesticide poisoning has been acknowledged as a serious problem in many agricultural communities of low and middle-income countries (WHO, 2004). Prolonged exposure to pesticides could lead to cardiopulmonary disorders, neurological and hematological and skin diseases (Davies et al., 1982).
  • From an environmental perspective, chemically-polluted runoff from fields has contaminated surface and ground waters, damaged fisheries and destroyed freshwater ecosystems. Vegetable plots were also often located next to waterways or ponds to facilitate irrigation, thus creating the potential for contamination. 
  •  Vegetables tend to be sprayed heavily up to the time of harvest, and then shipped directly to market with no waiting period; moreover, many are consumed whole.  These create a very significant potential for pesticide residues causing negative health effects on consumers. Most of the pesticides are prescribed to follow the safe period of 7 – 21 days for consumption. But, it is very rare to find such a practice followed by the farmers.
  • Organo-phosphorous pesticides were mainly used at different stages of vegetables growth. It is seen that different types of pesticides are used for single crop production. It is common to spray pesticide on vegetables such as brinjal several times a week. Brinjal producers used to apply pesticides from 15 to 35 times for one crop cycle. More aggravate scenario was found from a different study in Jessore district showed a range of pesticide application from 17 to 150 times in one crop cycle (BSS, 2008).
  • Around 47% of the farmers of Bangladesh were found to have overused pesticides, with an average overuse rate of 3.4 kg per growing season (Dasgupta et al., 2006). It was also found common to spray pesticides from 3 to 7 times for cauliflower and cabbage. Problems of toxic residues occur when proper procedures are not followed. The common causes of residue problems are that growers apply the wrong pesticide, or apply too much of it too soon before harvest. Sometimes this is because of ignorance or sometimes there is an outbreak of pests or disease shortly before harvesting. Farmers abuse chemicals because they lack guidance regarding how to use them. In some cases, the pesticide they use is not well suited to their pest problems, and is not very effective. In such cases, farmers spray pesticide repeatedly without killing the pest.
  • Around 30% farmers felt burning sensation during pesticide application. About 28% had breathing problem, around 13% felt dizzy, 17% itching and 16% burning of their eyes during pesticides application.       
  • Around 27% perceived that fish had been reducing and water pollution occurred due to wash-out of agrochemicals from agricultural farms. Excessive and unplanned use of pesticides also causes air and soil pollution.

  • Long term effects of pesticides

  • Improper and excessive use of chemical based pesticides is an enormous thread to human body. Most of the insecticides used by the farmers in our country containing organo phosphates and carbomates, which are main reason of Carcinogens (cancer) and effect the nervous system, hormone and endocrine systems as well. Several researches show that, some elements used in pesticides are  dangerous sources of breast cancer and weakened the immune system of the body. Children are seems to be susceptible to the toxic effect of pesticides. The Natural Defence Council reports that, higher incident of childhood leukemia, brain cancer, birth defects are co-related with early exposure of pesticides. Infants and young children consuming breast milk ingest pesticides. Pregnant women can pass pesticides on to their fetus. Women who eat fruits and vegetables that have been sprayed with pesticides, pass the pesticides on to their nursing children. Children eating foods that have been treated with hormones, antibiotics or pesticides have them in their bodies. A greater risk (70% increase) for Parkinson’s disease, even with low level of pesticides. In general fatigue, skin irritation, nausea, vomiting, breathing problem, brain disorder, blood disorder, lever and kidney damage, reproductive damage, different kinds of cancer etc. are very common diseases may occur from the elements of pesticides. We regularly taking pesticides especially through vegetables purchased from market as farmers shipped their production without maintaining any regulation and safe timing in spraying in their field.