The Lagos Lagoon is an area of salt and brackish water situated in the western part of Nigeria . The in vitro antibiotic sensitivity profiles of microbial isolates encountered in the 24 designated sampling sites of the Lagos Lagoon were determined. 46 (60%) of these microorganisms tested showed multiple antibiotic resistance. This included the enteric gram negative short rods such as Klebsiella
spp.and Escherichia coli
. The prevalence of multiple antibiotic resistant microorganisms in fresh water as well as marine environment may be important, since their presence indicates recent contamination with sewage. This resistant organisms may contaminate fish and other products within the food chain and if such are consumed by humans, it may become part of the individual flora. The Lagos Lagoon is populated with pathogenic bacteria and the pathogenic organisms are more likely to be found in area of low salinity than in areas of high salinity. The enteric organisms found in most areas showed multiple antibiotic resistances, which is significant healthwise.