In the present study, we assessed the environmental impact of the different sewage markers such as coliform and faecal coliform bacteria. Antarctica is the hub of fresh-water lakes. Now, these lakes have been contaminated through anthropogenic activities and wildlife populations, such as seals and penguins. The release of sewage waste in Antarctica can produce microbiological pollution in the lake water. Faecal coliform is a more suitable bacteria for the investigation of the anthropogenic impact on the Antarctic environment. Edwards et al. [15] & Hughes [18] studied that some strains of faecal coliforms, such as faecal enterococci and spore-forming bacillus can survive in Antarctica for 30–40 years. Fujioka et al. [21] & Kapuscinski and Mitchell [22] have described the effect of sunlight on E. Coli. Statham and McMeekin [11] studied the effect of solar radiation on the survival of E. Coli at Davis Research Station, Antarctica, and stated that faecal bacteria were rapidly inactivated when exposed to sunlight in the Antarctic water.
Several scientists have reported the presence of coliform and faecal coliform in the sewage outfall of the Antarctic research stations [7, 15, 23]. Coliforms are less able to survive in Antarctic environmental conditions than spore-forming bacteria. Nedwell et al. [24] stated that coliform bacteria can survive < 50 years while spore-forming bacteria can survive > 80 years in Antarctica. The faecal Streptococcus strain was more resistant to the effects of radiation than the gram-negative strains [11]. Fox and Cooper [25] reported that in some areas of Antarctica, regional warming has caused a decrease in permanent snow cover around nunataks and coastal regions with the result that previously buried toilet pits, depots, and food dumps are now melting out. Green et al. [7] reported a similar amount of coliform bacteria in the outfall of sewage from the Davis research station, which was reported in the sewage outfall of the McMurdo by Edwards et al. [15].
In our finding, faecal coliform bacteria were absent in all different lakes of Broknes & Grovnes peninsula, Larsemann Hills, East Antarctica. While coliform bacteria were present in two lakes (P2 Lake and P3 Lake) of Broknes peninsula and nine lakes (L1C NG, L1D NG, L1E NG, L7 NG, L7A NG, L7B NG, L2 SG, L4 SG, and L5 SG) of Grovnes peninsula. The present study confirms that lake water contamination is limited to the immediate vicinity of the sewage outfall and will be useful in the future for the assessment of the microbiological pollution in Antarctica.
Hughes and Blenkharn [5] studied the bacterial reproduction in the untreated sewage which was released from the Rothera Research Station, Antarctica. Goldsworthy et al. [26] reported the presence of faecel coliform bacteria in intertidal pools adjacent to sewage effluent from the research stations at Laersemann Hills, East Antarctica. Bruni et al. [27] reported the high concentration of the faecel bacteria (Sediment 94 CFU/100 mL; Water 800 CFU/100mL) in the sewage outfall from the Italian Research Station, Terra Nova Bay. Hughes and Nobbs [28] studied the viable faecel coliform bacteria in 30–40 years old human faeces which was dumped at Fossil Bluff Field Station, Alexander Island, Antarctic Peninsula. The previous methods of human waste disposal on land are now starting to produce environmental pollution as well as potential health and scientific problems.