Impact of chemical fertilisers on non-target organisms

The present study was conducted to investigate the effects of two chemical fertilizers, NPKs and triple superphosphate (TSP) applied at two doses (LD25 and LD50) on adults and juveniles of an earthworm bioindicator of pollution, Aporrectodea caliginosa, a dominant species in the region of Tebessa (North-East Algeria).The effects of these two chemical fertilizers were examined on mortality, growth, biomarkers of oxidative stress and biochemical composition of adults and juveniles of A. caliginosa. Bioaccumulation and histological studies were also determined. The growth of adult and juvenile worms was disturbed after exposure to both fertilizers (NPK and TSP) accompanied by a disturbance in protein content and energy reserves. Furthermore, biomarkers of oxidative stress revealed an induction of the detoxification system. Chemical fertilizers were accumulated in earthworms, but with a low bioaccumulation rate. In addition, histological study of treated adults revealed changes in the integuments and intestinal wall compared to controls.