Polycyclie aromatic hydrocarbons(PAHs) are a group of compounds consisting of two or more fused aromatic rings.Most of them are formed during incomplete combustion of organic materials such as wood and fossil fuels,pe...Polycyclie aromatic hydrocarbons(PAHs) are a group of compounds consisting of two or more fused aromatic rings.Most of them are formed during incomplete combustion of organic materials such as wood and fossil fuels,petroleum products,and coal.The composition of PAH mixtures varies with the source and is also affected by selective weathering effects in the environment.PAHs are ubiquitous pollutants frequently found in a variety of environments such as fresh water and marine sediments,the atmosphere,and ice.Due to their widespread distribution,the environmental pollution due to PAHs has aroused global concern.Many PAHs and their epoxides are highly toxic,mutagenic and/or carcinogenic to microorganisms as well as to higher forms of life including humans.The main aim of this review is to provide contemporary information on PAH sources,route of exposure,worldwide emission rate,and adverse effects on humans,especially with reference to cancer.展开更多
Objective:To determine the occurrence of Cryptosporidium species in catfish(Clarias gariepinus)harvested from two lakes and ponds in Zaria,Kaduna State,Nigeria.Methods:Catfish samples(n=200)from two lakes and(n=200)fr...Objective:To determine the occurrence of Cryptosporidium species in catfish(Clarias gariepinus)harvested from two lakes and ponds in Zaria,Kaduna State,Nigeria.Methods:Catfish samples(n=200)from two lakes and(n=200)from two private fish ponds were collected and their gills and gastrointestinal tract samples were analysed for Cryptosporidium oocysts using modified Ziehl-Neelsen staining technique was used,followed by microscopy.Results:Oocysts of Cryptosporidium species were found in all the sampling sites with an overall positivity rate of 49.75%.A comparison between the lakes and ponds as sampling sites revealed a statistically significant(P<0.05)higher percentage of occurrence of Cryptosporidium oocyst from the lakes(39.25%)than from the ponds(10.50%).Conclusions:These findings document for the first time the natural occurrence ofCryptosporidium sp.in catfish intended for human consumption and therefore,underlines the need for public enlightenment to guard against any possible zoonotic transmission.展开更多
基金Supported by UGC-Non net plan(Grant No.No:co/Tara/UGC-Non-Net/UGC-XII Plan/Pharamacology&ET/2014/706 dated 28th march2014)
文摘Polycyclie aromatic hydrocarbons(PAHs) are a group of compounds consisting of two or more fused aromatic rings.Most of them are formed during incomplete combustion of organic materials such as wood and fossil fuels,petroleum products,and coal.The composition of PAH mixtures varies with the source and is also affected by selective weathering effects in the environment.PAHs are ubiquitous pollutants frequently found in a variety of environments such as fresh water and marine sediments,the atmosphere,and ice.Due to their widespread distribution,the environmental pollution due to PAHs has aroused global concern.Many PAHs and their epoxides are highly toxic,mutagenic and/or carcinogenic to microorganisms as well as to higher forms of life including humans.The main aim of this review is to provide contemporary information on PAH sources,route of exposure,worldwide emission rate,and adverse effects on humans,especially with reference to cancer.
基金Supported by Ahmadu Bello University,Zaria,Nigeria with Grant No.ABU/P16945.
文摘Objective:To determine the occurrence of Cryptosporidium species in catfish(Clarias gariepinus)harvested from two lakes and ponds in Zaria,Kaduna State,Nigeria.Methods:Catfish samples(n=200)from two lakes and(n=200)from two private fish ponds were collected and their gills and gastrointestinal tract samples were analysed for Cryptosporidium oocysts using modified Ziehl-Neelsen staining technique was used,followed by microscopy.Results:Oocysts of Cryptosporidium species were found in all the sampling sites with an overall positivity rate of 49.75%.A comparison between the lakes and ponds as sampling sites revealed a statistically significant(P<0.05)higher percentage of occurrence of Cryptosporidium oocyst from the lakes(39.25%)than from the ponds(10.50%).Conclusions:These findings document for the first time the natural occurrence ofCryptosporidium sp.in catfish intended for human consumption and therefore,underlines the need for public enlightenment to guard against any possible zoonotic transmission.
