Jayanta Kumar Biswas

Unfortunately, in the original publication of the article, Prof. Yong Sik Ok’s affiliation was incorrectly published.

Environmental Health Engineering And Management Journal مجله مدیریت و مهندسی بهداشت محیط

Water and soil pollution by toxic heavy metals (HMs) is increasing globally because of increase in population, industrialization and urbanization. It is a burning problem for the public, scientists, academicians and politicians how to tackle the toxic contaminants which jeopardize the environment. One possible solution for pollution abatement is a bioremediation-effective and innovative technology that uses biological systems for treatment of contaminants. Many bacteria synthesize indole-3-acetic acid (IAA) which is a product of l-tryptophan metabolism and belongs to the auxin class of plant growth-promoting hormone. The present study aimed at assessing the resistance pattern of wastewater bacteria against multiple HMs and plant growth promotion activity associated with IAA. A Gram-negative bacterial strain Pseudomonas aeruginosa KUJM was isolated from Kalyani Sewage Treatment Plant. This strain showed the potential to tolerate multiple contaminations such as As(III) (50 mM), As(V) (800 mM), Cd (8 mM), Co (18 mM), Cu (7 mM), Cr (2.5 mM), Ni (3 mM) and Zn (14 mM). The capability of IAA production at different tryptophan concentration (1, 2, 5 and 10 mg mL⁻¹) was determined, and seed germination-enhancing potential was also estimated on lentil (Lens culinaris). Such type of HM-resistant, IAA-producing and seed germination-enhancing P. aeruginosa KUJM offer great promise as inoculants to promote plant growth in the presence of toxic HMs, as well as plant inoculant systems useful for phytoremediation of polluted soils. Hence, P. aeruginosa KUJM finds significant applications in HM-contaminated poor agricultural field as well as in bioremediation of HM-contaminated wastewater system.

The study examined the impact of raking and fish bioturbation on modulating phosphorus (P) concentrations in the water and sediment under different trophic conditions. An outdoor experiment was set to monitor physicochemical and microbiological parameters of water and sediment influencing P diagenesis. A pilot study with radioactive ³²P was also performed under the agency of raking and bacteria (Bacillus sp.). Raking was more effective in release of P under unfertilized conditions by significantly enhancing orthophosphate (35%) and soluble reactive phosphate (31.8%) over respective controls. Bioturbation increased total and available P in sediments significantly as compared to control. The rates of increase were higher in the unfertilized conditions (17.6–28.4% for total P and 12.2 to 23.2% for available P) than the fertilized ones (6.5–12.4% for total P and 9.1 to 15% for available P). The combined effects of raking and bioturbation on orthophosphate and soluble reactive phosphate were also stronger under unfertilized state (54.5 and 81.8%) than fertilized ones (50 and 70%). The tracer signature showed that coupled action of introduced bacteria and repeated raking resulted in 59.2, 23 and 16% higher counts of radioactive P than the treatments receiving raking once, repeated raking and bacteria inoculation, respectively. Raking alone or in sync with bioturbation exerted pronounced impact on P diagenesis through induction of coupled mineralization and nutrient release. It has significant implication for performing regular raking of fish-farm sediments and manipulation of bottom-grazing fish to regulate mineralization of organic matter and release of obnoxious gases from the system. Further, they synergistically can enhance the buffering capacity against organic overload and help to maintain aquatic ecosystem health.

The objective of this research was to investigate the effects of biosolids on the competitive sorption and lability of the sorbed Cd, Cu, Ni, Pb, and Zn in fluvial and calcareous soils. Competitive sorption isotherms were developed, and the lability of these metals was estimated by DTPA extraction following their sorption. Sorption of all metals was higher in the fluvial than in the calcareous soil. Sorption of Cu and Pb was stronger than that of Cd, Ni, and Zn in all soils. Biosolids application (2.5%) reduced the sorption of all metals especially Cu and Pb (28–43%) in both soils (especially the calcareous soil) at the lower added metal concentrations (50 and 100 mg L⁻¹). However, it increased the sorption of all metals especially Pb and Cu in both soils (especially the calcareous soil; 15.5-fold for Cu) at the higher added concentrations (250 and 300 mg L⁻¹). Nickel showed the highest lability followed by Cd, Zn, and Pb in both soils. Biosolids increased the lability of the sorbed Ni in the fluvial soils at all added concentrations and the lability of Cd, Pb, and Zn at 50 mg L⁻¹, but decreased the lability of Cd, Pb, and Zn at 250 and 300 mg L⁻¹ in both soils. We conclude that at low loading rate (e.g., 50 mg L⁻¹) biosolids treatment might increase the lability and environmental risk of Cd, Cu, Pb, and Zn. However, at high loading rate (e.g., 300 mg L⁻¹) biosolids may be used as an immobilizing agent for Cd, Cu, Pb, Zn and mobilizing agent for Ni.

Hazardous bleaching and dyeing units are rapidly increasing in developing countries due to growing global demand of textile products. The aim of the study is to assess long-term respiratory effect of air pollution generated from textile bleaching and dyeing industries on the residents living in such industrial setting. Such types of long-term (2012-2016) studies have been conducted first time in this area. The control area of Chatta and Kalikapur under Maheshtala textile cluster (10.45°N latitude to 75.90°E longitude) has been identified for the study. Ambient air monitoring with particulate matters (PMs; PM _2.5 and PM ₁₀ ), NO ₂ , and SO ₂ of 72 air samples has been done with air sampler machine during different seasons. The concentrations of PM _2.5 and PM ₁₀ have been found higher than Central Pollution Control Board (India) and World Health Organization norms. Using data on 73 respondents on age, education, occupation, and income, impact on different causes of respiratory ailments has been examined. The survey shows that 67% of total population are having different respiratory complaints. The regression analysis ( R ² = 0.9998) and correlation matrix show that cold, cough, bronchitis, asthma, and chronic obstructive pulmonary disease (COPD) have a strongly significant positive correlation with fever ( r = 0.98, P < 0.05); breathing trouble has a significant strong positive correlation with cold, cough, bronchitis, asthma, COPD, and fever ( r = 0.877, P < 0.05); high blood pressure has a negative correlation with cold and fever ( r = −0.655, P < 0.05); cardiovascular problem has a strong positive correlation with high blood pressure ( r = 0.989, P < 0.05) and strong negative correlation with cold, cough, asthma, bronchitis, and cold-related fever ( r = −0.54, P < 0.05) due to PM _2.5 and PM ₁₀ concentration. About 56% of villagers who have opted for this occupation have school-level education (class I-IV) with annual income of Rs 60 000 ($870) only. Studies express present scenario of air pollution in the subject area which is still unnoticed and propose to take control of air pollution.