Significantly elevated levels of DNA damage observed
Significantly elevated levels of DNA damage observed in peripheral blood of tea garden women workers indicate the occupational exposure. The same was observed in cholinesterase activities, which detected lower activity in the exposed group compared to non-exposed. Large volumes of pesticides are used in India for agriculture. Out of 230 pesticides registered in India 37 chemicals have been approved for use in tea plantation by Central Insecticide Board of India. The majority of pesticides used are hazardous for humans as well as to the environment. Pesticides have been reported to be genotoxic, generating free radicals that react with cell membranes and initiate the process of lipid peroxidation. The accumulation of these radicals can cause oxidative stress, depending on the antioxidant capacity of individuals exposed to these pesticides . Continuous exposure and persistence of unrepaired genotoxic damage induced by pesticides and the formation of free radicals can lead to a higher level of cytogenetic alterations . The main ZLN005 path for pesticides among workers is through the skin and the respiratory system . Therefore the use of appropriate clothes, masks and gloves is necessary to prevent the contamination. Several studies have elucidated genotoxicity in pesticide exposed population and the importance of PPE usage . Only 21% of the workers in our study reported usage of appropriate PPEs. A lower ChEs activity observed together with an increase in DNA damage might be attributed due to their lack of knowledge on safe work practice and unhygienic condition. A possible explanation is that workers from rural areas, like those in most of developing countries, do not always pay enough attention to the renewal or cleaning of their protective clothing or equipment. If the equipment is seldom changed or cleaned, the effective protection afforded by them can be very low. Furthermore, the exposure to multiple pesticides may cause various cells injuries and DNA damage, which depends on type of pesticide, frequency, quantity and duration of exposure [50,51]. It is well known that increased genotoxicity in individuals occupationally exposed to pesticides is related to cancer risk and genetic illness. The DNA damage observed in the current investigation may be due to insufficient protective measures adopted by the exposed workers or multiple exposures to pesticides in the tea garden. Previous studies show that the age and tobacco chewing habits associated with genotoxicity . Similarly, positive genotoxicity has been reported in pesticide exposed workers who had used very few protective measures. A large number of studies have reported genotoxic effects on workers exposed to pesticides with the increase in duration of exposure . There was no significant influence of age, year of experience, tobacco chewing and PPE use on DNA damage in the exposed groups. The DNA damage observed in the workers may be a consequence of oxidative damage resulting from their exposure to pesticides. Genotoxic evaluation using these tests is necessary to ensure good occupational conditions and the health of workers. Additionally, a large number of women workers plucking the tea leaves with their bare hands, and also, that an important number of them were exposed to pesticides by working during their pregnancies. This observation showed the possibilities of epigenetic modulations as a result of pesticide exposure and a possible link between pesticides and the chronic and transgenerational effects. Since the workers get exposed to a complex mixture of chemicals, it is difficult to attribute the genotoxic effect to a particular chemical class or compound. There is a lack of information about the toxicity of substances in complex mixtures and are often avoided by assuming that the toxicity of a mixture is simply the sum of the expected effects from each mixture component, i.e. synergistic or antagonistic interactions . Biomonitoring studies of workers exposed to various types of pesticides are rather specific because different populations have different lifestyles, nutritional habits, climatic and environmental conditions and are exposed to different mixture of pesticides. This could explain why some studies have found an increase in genetic damage whilst in other studies the results were negative. Although the information on exposure levels and genotoxicity of several pesticides used can be considered significant, there is a lack of information concerning genotoxic effects of complex mixtures of pesticides.