Chlorophenol compounds and their derivatives are ubiquitous contaminants in the environment. These compounds are used as intermediates in manufacturing agricultural chemicals, pharmaceuticals, biocides, and dyes. Chlorophenols gets into the environment from a variety of sources such as industrial waste, pesticides, and insecticides, or by degradation of complex chlorinated hydrocarbons. Thermal and chemical degradation of chlorophenols leads to the formation of harmful substances which constitute public health problems. These compounds may cause histopathological alterations, genotoxicity, mutagenicity, and carcinogenicity amongst other abnormalities in humans and animals. Furthermore, the recalcitrant nature of chlorophenolic compounds to degradation constitutes an environmental nuisance, and a good understanding of the fate and transport of these compounds and their derivatives is needed for a clearer view of the associated risks and mechanisms of pathogenicity to humans and animals. This review looks at chlorophenols and their derivatives, explores current research on their effects on public health, and proffers measures for mitigation.

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ABSTRACT:In different parts of the world, attention is being paid to exploitation of higher plants as biodegradable fungicides in the control of most plant pathogenic fungi. Different spices of the Zingiberaceae family have been tested for their antifungal properties, but there exists little or no information on the antifungal potential of a particular member of that family; Aframomum sceptrum on fungal pathogens of some economic important palms in Nigeria. In this study, the phytochemical composition of the seed extracts of this spice was analyzed by standard methods while the antifungal activities of polar and non polar extracts of the spice was tested on two major isolates affecting the Oil palm, Fusarium oxysporum f.sp elaeidis and Hypocrea lixii (IMI 501885) Cold extraction using Acetone, Ethanol, Hexane, Methanol, and Diethylether solvents were used in the seed extract preparation. The broad spectrum fungicide, Mancozeb (80% wettable powder) was used as the positive control while the negative control was Dimethyl sulphoxide. The Dimethyl sulphoxide was also used to reconstitute the solvent extracts by dissolving the extracts and fungicides in appropriate amount of 15 % (v/v) to obtain a concentration of 0.0624g/ml. The phytochemical screening revealed the presence of the following phytochemicals in different quantities; Alkaloids, Terpenoids, Anthraquinones, Flavonoids Tanins, Saponins. Results obtained showed that all the extracts had a significantly higher antifungal effect (p< 0.05) than the broad spectrum fungicide, Mancozeb at 2000ppm. Non polar hexane seed extract had the highest percentage inhibition of 60.26% on Hypocrea lixii (IMI 501885 while the Polar ethanolic extracts with a percentage inhibition of 52.73 % on Fusarium f.sp elaeidis. Amongst all the extracts used in this study, the seed extracts that gave a low percentage inhibition of 42.45% was the non -polar acetone seed extract on Fusarium oxysporum fsp. elaeidis and methanol extract on H .lixii with the least percentage inhibition of 42.31%. The implications of these findings are discussed. © JASEM http://dx.doi.org/10.4314/jasem.v18 i2.4

Trichoderma species isolated from soil was investigated for ability to control wilt disease of tomato seedlings in sterile potted soil. The roots of four weeks old tomato seedlings were treated with different spores concentration (10 3 /10 6 spores/ml) of Trichoderma species and placed into sterile soil inoculated with 10 6 spores/ml) of Fusarium oxysporum f. sp. lycopersici. The different spores concentration (10 3 and 10 6 spores/ml) of Trichoderma species prevented wilt disease development in the tomato seedlings in varying degrees. Tomato seedlings were effectively protected from infection when the pathogen F. oxysporum f. sp. lycopersici and Trichoderma species were iniculated simultaneously. Control of wilt disease was less effective when spores of F. oxysporum f. sp. lycopersici were allowed to grow one day ahead of spores of Trichoderma species. And there was no protection when the spores of F. oxysporum f. sp. lycopersici were allowed to grow two days ahead of Trichoderma species.

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