Environmental Health Engineering and Management Journal
Environmental Health Engineering and Management Journal
Environ. Health Eng. Manag.
Medical Sciences
http://ehemj.com
1
admin
2423-3765
2423-4311
8
7
14
8888
13
en
jalali
1399
7
1
gregorian
2020
10
1
7
4
online
1
fulltext
en
Rapid assessment of toxicity of chlorinated aqueous solution by dissolved oxygen depletion and optical density bioassays
عمومى
General
مقاله اصیل
Original Article
<div style="text-align: justify;">Background: Chlorination of wastewater effluent with high levels of residual organic matter has been suspected to the production of toxic and hazardous disinfection by-products (DBPs) including trihalomethane (THM) compounds.<br>
Methods: In this study, two rapid techniques including dissolved oxygen depletion (DOD) and optical density (OD) bioassays were used to evaluate the chloroform toxicity of aqueous solution. The activated sludge was collected from aeration tank of a full-scale municipal wastewater treatment plant and used as a biological inoculum. In order to achieve an active and stabilized mixed culture of bacteria, the test cultures were transferred to a fresh nutrient broth culture media every day. The influence of chloroform on DOD and OD bioassays was examined at chloroform initial concentrations of 10-1000 μg/L.<br>
Results: It was revealed that the application of chloroform at concentrations of 100 and 1000 μg/L showed moderate and extreme toxicity, respectively, and reduced bacterial activity. The estimated chemical concentration with 50% inhibition of bacterial activity for DOD and OD bioassays was 457 and 961 μg/L, respectively.<br>
Conclusion: According to the results, the wastewater effluent should use bioassays in order to evaluate the effects of DBPs where the wastewater effluent is disinfected by chlorine compounds.</div>
Trihalomethanes, Chloroform, Disinfection, Wastewater, Biological assay, Oxygen, Inhibition
271
276
http://ehemj.com/browse.php?a_code=A-10-1-190&slc_lang=en&sid=1
Mohammad Mehdi
Amin
mohammadmehdia@gmail.com
10031947532846007329
10031947532846007329
No
1Environment Research Center, Research Institute for Primordial Prevention of Non-communicable Diseases, Isfahan University of Medical Sciences, Isfahan, Iran, 2Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran
Ali
Fatehizadeh
fatehizadeh@gmail.com
10031947532846007330
10031947532846007330
No
1Environment Research Center, Research Institute for Primordial Prevention of Non-communicable Diseases, Isfahan University of Medical Sciences, Isfahan, Iran, 2Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran
Nasrin
Bagheri
n_bagheri70@yahoo.com
10031947532846007331
10031947532846007331
Yes
Corresponding author: Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran, and Student Research Center, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran