Discipline: Biological Sciences
Subcategory: Pollution/Toxic Substances/Waste
Room: Marriott Balcony B
Hanan Ali - Texas Southern University
Co-Author(s): Maruthi Sridahr Balaji Bhaska, Texas Southern University, Texas, Houston; Jason A. Rosenzweig;Texas Southern University, Texas, Houston
The Tigris River is one of the largest rivers in Middle East, and it divides Baghdad into two parts (Karkh & Risafa areas). The Tigris River serves as one of the main source of drinking water in Baghdad and other cities. Constant monitoring and assessment of river water quality is a fundamental and needed for protecting both environmental and human health. Armed conflicts and socio- economic changes during recent years have made it difficult to monitor the water quality. As such, we strove to evaluate chemical and microbial contaminants present in the Tigris River waters. More specifically, we sought to: 1) identify the heavy metal and nutrient concentrations found in the water and soil of Tigris River, 2) enumerate and detect the bacterial loads, and3) evaluate cytotoxic effects of Tigris River water on human gut cells (HT29). By employing inductively coupled plasma mass spectrometry (ICP-MS), the heavy metal and nutrient concentrations of our 2018 Tigris River water samples were identified. To detect the total microbial and indicator bacteria concentrations, water samples were plated on MacConkey and Luria Broth (LB) agar. Heavy and toxic metal concentrations were similarly measured in our Tigris River water and soil samples and found to be significantly high in all collection sites [latitude and longitude N 33˚ 17’20.4314” and E 44’26’58.6483 (site1: 33.309529˚,, 44.414391˚), (site 2: 33.406039˚, 44.33915˚ ), and (site 3: 33.289009˚, 44.449652˚)]. For both water and soil samples, high percentages of heavy metals (including: cadmium, arsenic, copper, aluminum, barium, and lead), were observed relative to United States Environmental Protection Agency standards. Additionally, high concentrations sodium, and magnesium were also observed. In contrast, microbial loads in Tigris River water samples were low, particularly levels of coliform bacteria. More specifically, we found the total bacterial loads of 65,000 cfu/100 mL while fecal coliform counts were less than 1.5 cfu/100 ml. With regards to HT-29 gut cell cytoxicity studies, we observed a dose-dependent effect, where higher exposure concentrations led to increased cellular cytotoxicity. Overall, our studies provide baseline data that could prompt further studies and contribute to improved ecological health of the Tigris River.
Funder Acknowledgement(s): NSF/ HBCU-UP, SURE Summer Program, Environmental Toxicology Department.
Faculty Advisor: Jason A. Rosenzweig,Maruthi Sridahr Balaji Bhaska, Jason.Rosenzweig@tsu.edu
Role: Sampling collection, Bacterial Analysis, Toxicity cellular analysis, and chemical analysis. As well as writing and interpret the results.