20 guppies (Poecilia reticulata) and 30 zebrafish (Danio rerio) were placed in a fish tank (fish were kept together to avoid synchronized movements) and examined under 5 different conditions: 1) control group (no exposure, fish fed) 2) sham exposure (visual presence of the mobile phone in the tank, fish fed), 3) sham exposure, fish starved, 4) exposure to the electromagnetic field (mobile phone in the tank) and fish starved, 5) exposure to the electromagnetic field and fish fed.
0 Hz–1,800 MHz
Modulation type: pulsed
Exposure duration: continuous for 3 minutes
|Chamber||glass fish tank (41 x 33 x 27 cm3); three sides of the glass tank were covered with white paper to avoid visual distractions and insulate thermal conduction; the top was uncovered for light and the front was uncovered for recording the movement of the fish|
|Setup||the cell phone that was sealed in a plastic (polyethylene) bag and was merged to the left side of a fish tank, a wired earphone and a microphone were connected to control the act of turning-on and turning-off the cell phone; the battery part of cell phone was placed more than 12 cm below the water surface, and the antenna was merged about 9 cm underneath of water surface (to minimize the acoustic noise and static field); the top portion (location of speaker) was placed partially above water surface; cell phone was set on silent mode without vibration; a static magnetic field was generated by part of the speaker (top portion of the cellular phone that was placed partially above the water surface) when phone was turned on|
|Sham exposure||A sham exposure was conducted.|
|magnetic flux density||195 µT||maximum||measured||-||signal on, in air, 1 cm distance to the mobile phone|
|magnetic flux density||88 µT||minimum||measured||-||signal on, in air, 4 cm distance to the mobile phone|
|magnetic flux density||121 µT||maximum||measured||-||signal on, in water, 1 cm distance to the mobile phone|
|magnetic flux density||45 µT||minimum||measured||-||signal on, in water, 1 cm distance to the mobile phone|
|magnetic flux density||53 µT||-||measured||-||± 2 µT; static magentic field from speaker; in air, 3 cm distance to the mobile phone|
The results showed that the fish reacted positively or negatively to the electromagnetic field depending on their feeding status: when fed they avoided the mobile phone, when starved they approached.
The authors conclude that exposure of small fish to a GSM 1800 MHz electromagnetic field could affect the locomotor activity depending on the feeding status.