الفهرس 
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Abstract
Pest control depends mostly on chemical esticides which probably affect adversely the environment. The total amounts of the pesticides used are very high and the effective concentrations may be large. The biological tools in pest control presented partial solution but for some reasons, the biological control did not take good position in pest control. This can be attributed to the difficulties of mass production of the biological organisms and accumulation of some agents such as bacteria and viruses in the environment. In this work, the results of testing of hematoporphyrine as photoinsecticide and photomolluscicides is presented. This class of compounds is friendly to the environment with a high photosensitizing activity towards biological systems. These compounds have been already approved for medical use in the photodynamic therapy of tumors and other diseases. Hematoporphyrine becomes toxic only when it is activated by sunlight. The present results reveal that hematoporphyrine are very active against the present two medically important organisms, namely Culexpipiens larvae and Lymnaea natalensis (snail vector of Fasciola gigantica) which are known to transport and cause certain diseases of human beings. Both organisms appeared to consume enough of hematoporphyrine to exert its phototoxic action when they are exposed to light from solar simulator or direct solar irradiation. The results reveal that using the Confocal Laser Scanning Microscope (CLSM) was suitable to determine the optimum photosensitization reaction parameters related to each organism. Hematoporphyrine had a high ability to accumulate inside the larvae organs and snail eggs. But the effective accumulation was recognized after 6 hours accumulation for Culex larvae and 1-6 hours for Lymnaea eggs. The efficiency of photosensitization reaction on Lymnaea natalensis eggs proved to be affected by certain environmental conditions such as minerals, pH, temperature and water depth. He-Cd laser (325nm and 442nm) had a significant role in reducing the longevity of Lymnaea snails which hatched from laser exposed eggs for 0.5 - 3 minutes exposure in the case of He-Cd laser wavelength 442 and 0.5 - 35 minutes exposure in the case of He-Cd laser wavelength 325 nm.