ABSTRACT
For decades, the Buriganga River in Dhaka, Bangladesh, has suffered from persistent pollution, leading to heavy metal contamination in fish samples that poses significant risks to human health. This study conducted an analysis of the whole bodies of various fish species, including Heteropnuestes fossilis, Channa punctatus, Notopterus notopterus Channa striata and Colisa fasciata to examine the concentrations of Chromium, Manganese, Nickel, Copper, Zinc, Arsenic, Cadmium, Barium, and Lead. The analysis was performed using inductively coupled plasma mass spectrometry, revealing notable concentrations of Pb, Ni, Cd, and Zn, with average levels of 6.85, 156.77, 0.41, and 3.37 mg/kg, respectively. Assessment of target hazard quotients for Pb, against recommended benchmark doses of observable effects, indicated levels 2 to 6 times higher than the recommended safety thresholds. The cumulative totals of target hazard quotients across multiple specimens exceeded 2 and, in some cases, reached up to 7, surpassing the safety cutoff of 1. The risk of cancer from Ni and Pb was calculated to be 1 in 10,000 on average for each, classifying it as a moderate risk. Quantitative analysis revealed that heavy metal concentrations of Pb, Ni, Cd, and Zn in most fish samples exceeded reference safety values. Simultaneously, hazard analysis identified critical concerns regarding Pb content in one sample, and cumulative toxin loads in almost every sample were deemed unsafe for regular consumption. In addition to quantitative assessments, a qualitative survey employed observation techniques, focus group discussions, and key informant interviews to investigate consumption behaviors and viewpoints on fish contamination. The results revealed that consumers generally held an enthusiastic attitude towards consuming these fish and were largely unaware of the associated health hazards.
ABSTRACT
OBJECTIVE: Urine is the most frequent specimen received for culture/sensitivity by clinical laboratories. The microbiological performance of HiCrome UTI agar medium was compared with Blood agar and MacConkey agar for isolation and presumptive identification of bacteria from urine culture. METHODS: A total of 443 consecutively collected midstream and/or catheter-catch urine samples from patients attending the Islami Bank Medical College Hospital, Rajshahi, Bangladesh during January to December, 2012 were cultured. Urine samples showing pus cells ≥ 5/HPF were inoculated on to Blood agar (BA), MacConkey agar (MAC) and HiCrome UTI agar (CA) media simultaneously and incubated overnight aerobically at 37(0)C. Rate of isolation and presumptive identification of bacterial species were compared for different media. RESULTS: Culture yielded a total of 199 bacterial isolates from 189 (42.67%) positive plates including 179 (40.40%) unimicrobial and 10 (2.26%) polymicrobial (mixed growth of pair of bacteria) growths. Both HiCrome UTI agar and Blood agar media supported 100% growths while 151 (75.88%) growths were observed on MacConkey agar. The rate of presumptive identification was found significantly higher on HiCrome UTI agar (97.49%) than MAC agar (67.34%) (P<0.001) as primary urine culture medium. Of 199 isolates, E. coli was found to be the leading uropathogen isolated from 118 (59.30%) samples with its presumptive identification rate of 95.76%, 93.22% and 5.93% on CA, MAC and BA respectively. All 10 (100%) polymicrobial growths were demonstrated distinctly on CA against only 01(10%) on each BA and MAC. CONCLUSION: HiCrome UTI agar was found to be more useful as primary urine culture medium in both higher rate of isolation and presumptive identification of uropathogens in comparison to conventional media. Its inherent characteristics in demonstrating polymicrobial growth and ease of rapid identification by distinct colony colour are unique.
