Gujarat Global News Network, Ahmedabad
People pay heavy price for organic foods just to make sure that they do not have harmful food containing pesticides. But this may not be true. Their food may have pesticides and heavy metal as in the case of tests on organic vegetables conducted by Ahmedabad based Consumer Education and Research Centre (CERC).
The international fame organization tested nine organic samples of two commonly consumed leafy vegetables, spinach and fenugreek, from various sources for the presence of pesticides and heavy metals. Two samples out of nine contained pesticide residues and five had varying levels of heavy metals.
Many synthetic pesticides and all heavy metals tend to be non-biodegradable and persistent. Accumulation in the body leads to adverse health effects.
It tested five samples of organic spinach, four samples of organic fenugreek and two samples each of non-organic spinach and fenugreek. They were tested for 36 pesticides and three heavy metals – lead, copper and arsenic. The samples were tested against the values set by the Food Safety and Standards (Contaminants, Toxins & Residues) Regulations, 2011.
The sample of organic spinach and fenugreek procured from Mangalam Organic Farm showed presence of trace levels of pesticide residues. Parathion methyl was detected in spinach (0.032 mg/kg) and fenugreek (0.073 mg/kg). Among the non-organic samples, the fenugreek sample from Big Basket showed trace levels of pesticide residues of chlorpyrifos (0.053 mg/kg). The two pesticides detected – chlorpyrifos and parathion methyl – belong to the organophosphate group.
Also, three out of five samples of organic spinach and two out of four of organic fenugreek had varying levels of heavy metals. None of the samples contained arsenic. Ironically, while one organic sample of spinach contained pesticide residues, both the non-organic samples were free of pesticides!The sample of spinach (from Think Organic) had higher levels of lead and copper than the two non-organic samples.
In the case of fenugreek, the two organic samples (Think and Big Basket) that contained lead and copper, had much higher levels than the non-organic samples (Big Basket and Mahalaxmi Vegetables). The presence of heavy metals in both organic and non-organic vegetables is a matter of concern for consumers.
Rinsing reduces pesticides on the surface of vegetables, but it can’t remove those that are absorbed by the roots and make their way into the plant’s tissue. Because of their large surface areas, leafy vegetables are likely to have high levels of pesticide residues.
Health implications: Over a long duration even microscopic quantities of pesticides can harm as they get accumulated in the body. Pesticide residues are particularly harmful for children, the elderly and those having chronic ailments like asthma.
Exposure to high levels of parathion methyl, even for short periods, may result in changes in the nervous system, leading to headaches, dizziness, confusion, blurred vision and difficulty in breathing. The United States Environmental Protection Agency (EPA) has banned the use of that insecticide on food crops commonly consumed by children. Chlorpyrifos has been linked with delays in learning, reduced physical coordination and behavioural problems in children.
Heavy metal contamination may occur due to irrigation of agricultural land with wastewater containing municipal wastes and industrial effluents. This leads to build-up of metals at the sites. The metals get accumulated in the crops growing there. The addition of inorganic fertilizers and metal based pesticides is another cause for heavy metal contamination.Leafy and tuberous vegetables tend to accumulate higher concentration of heavy metals than grains and fruits.
Health implications: The intake of heavy metal-contaminated vegetables poses a threat to human health. Lead is a toxic metal especially hazardous for children. It can accumulate in the body and harm almost every organ system. Hence, even low levels of exposure can be harmful. Very large single or long-term intakes of copper may cause male infertility. Exposure to copper can also damage the liver and immune system. Long-term exposure to arsenic from food can cause cancer and cardiovascular disease.
Organic vegetables are much more expensive than non-organic ones. For instance, 1 kg of organic fenugreek procured from Big Basket cost Rs. 126, while 1 kg of non-organic fenugreek bought from the same seller cost Rs. 10! The organic variety was more than 12 times the price of the non-organic one.