engleski

EFFECT OF ACUTE EXPOSURE TO MOBILE PHONE RADIOFREQUENCY ON THE ANTIOXIDATIVE RESPONSE IN LARVAE OF HONEYBEE (APIS MELLIFERA)

Although the absorbed energy from mobile phones cannot break chemical bounds, the results of many studies have shown that exposure to radiofrequency radiation (RF) at the operating frequency of mobile phones (900 MHz) can induce various biological effects, for example oxidative stress, genotoxic effects, production of the stress proteins, change in the functional activity of hemoglobin, dysfunction of the immune system as well as neurological effects. Most of these mentioned effects were documented in various mammals’ tissues. Previous studies regarding RF at frequencies from 900 MHz to 2.4 GHz in honey bees mostly investigated honey bee behavior, honey production, reproductive capacity and navigational skills. However, there is no investigation available which shows that RF has effects upon antioxidant status in honey bee larvae after acute exposure to radiofrequency at 900 MHz. The aim of this study was to measure the activity of antioxidants like glutathione S-transferase (GST), superoxide dismutase (SOD), catalase (CAT) and level of lipid peroxidation (thiobarbituric acid reactive substance, TBARS) in larvae of honey bee after exposure to RF at the operating frequency of mobile phones (900 MHz) in laboratory conditions. Exposure of honey bee larvae to a homogeneous electromagnetic field was carried out in the gigahertz transversal electromagnetic (GTEM) cell. The four to six days old honeybee brood in original combs were exposed to continuous radiofrequency electromagnetic field (RF-EMF) and modulated signal (80% AM 1 kHz sinusoidal) at frequency of 900 MHz and field level of 23 V/m for 2 hours. For each exposure six pieces of wax combs with four honeybee larvae were placed at the center of the GTEM cell with the uniform field distribution (± 0.1 dB). All parameters were measured spectrophotometrically. CAT activity was assayed by measuring the decrease in absorbance at 240 nm. GST activity was determined at 340 nm using 1-chloro-2, 4-dinitrobenzene (CDNB). The activity of SOD was assayed by the xanthine oxidase/cytochrome c method while the level of lipid peroxidation was measured as the formation of TBARS. The GST activity in the larvae of honey bee exposed to RF-EMF modulated signal at frequency of 900 MHz and field level of 23 V/m was statistically decreased while the CAT activity was significantly increased. On the other side, the SOD activity and level of TBARS were not statistically different when compared to controls. It can be concluded that short-term exposure (2 hours) to RF-EMF modulated signal at frequency of 900 MHz and field level of 23 V/m may induce alteration in the activities of antioxidant enzymes in the younger honeybee brood.

radiofrequency radiation ; honey bee ; larvae ; antioxidants

nije evidentirano