The application of system dynamics in different practices of a waste management system

The continuous increase in waste generation warrants global management of waste to reduce the adverse economic, social, and environmental impact of waste while achieving goals for sustainability. The complexity of waste management systems due to different waste management practices renders such systems difficult to analyze. System dynamics (SD) approach aids in conceptualizing and analyzing the structure, interactions, and mode of behavior of the complex systems. The impact of the underlying components can therefore be assessed in an integrated way while the impact of possible policies on the system can be studied to implement appropriate decisions. This review summarizes various applications of SD pertinent to the waste management practices in different countries. Practices may include waste generation, reduction, reuse/recovery, recycling, and disposal. Each study supports regional-demanding targets in environmental, social, and economic scopes such as expanding landfill life span, implementing proper disposal fee, global warming mitigation, energy generation/saving, etc. The interacting variables in the WMS are specifically determined based on the defined problem, ultimate goal, and the type of waste. Generally, population and gross domestic product can increase the waste generation. An increase in waste reduction, source separation, and recycling rate could decrease the environmental impact, but it is not necessarily profitable from an economic perspective. Incentives to separate waste and knowledge about waste management are variables that always have a positive impact on the entire system.

     

The effect of diazinon on blood glucose homeostasis: a systematic and meta-analysis study

Environmental Science and Pollution Research - Though evidence exists on the association between diazinon (DZN), an organophosphate pesticide, with hyperglycemia, contrasting reports also exist....     

Drought effects on the Iranian economy: a computable general equilibrium approach

Environment, Development and Sustainability - In the last two decades, recurring drought becomes a challenge for Iran’s economy, which is located in a drought-prone area, and it has been...     

Statistical analysis of arsenic contamination in drinking water in a city of Iran and its modeling using GIS

In this research, probable arsenic contamination in drinking water in the city of Ardabil was studied in 163 samples during four seasons. In each season, sampling was carried out randomly in the study area. Results were analyzed statistically applying SPSS 19 software, and the data was also modeled by Arc GIS 10.1 software. The maximum permissible arsenic concentration in drinking water defined by the World Health Organization and Iranian national standard is 10 μg/L. Statistical analysis showed 75, 88, 47, and 69% of samples in autumn, winter, spring, and summer, respectively, had concentrations higher than the national standard. The mean concentrations of arsenic in autumn, winter, spring, and summer were 19.89, 15.9, 10.87, and 14.6 μg/L, respectively, and the overall average in all samples through the year was 15.32 μg/L. Although GIS outputs indicated that the concentration distribution profiles changed in four consecutive seasons, variance analysis of the results showed that statistically there is no significant difference in arsenic levels in four seasons.     

Biogenic synthesis of gold nanoparticles using Satureja rechingeri Jamzad: a potential anticancer agent against cisplatin-resistant A2780CP ovarian cancer cells

Environmental Science and Pollution Research - Drug resistance of cancer cells is a major issue in cancer treatment. Plant-mediated nanoparticle synthesis has been applied in recent years to...     

Interactions of tillage and rainfall on atrazine leaching under field and laboratory conditions

Laboratory studies were conducted to evaluate effects of tillage reversal and rainfall on ¹⁴C-atrazine (2-chloro4-ethylamino-6-isopropylamino- -triazine) leaching patterns. Twelve intact soil cores (16 cm dia x 20 cm deep) were collected from 8-yr no-till (NT) fields. Half the cores were tilled (5 cm deep) prior to ¹⁴C-atrazine treatment (2.7 mg core⁻¹) to all cores. All cores received two rains (27 mm rain in 1.5 h, one day after application followed, two days later, by a 17 mm rain in 2.5 h) and leachate was collected and analyzed for atrazine. These rains simulated the timing, amount and duration of natural rainfall events from a tillage reversal field study. During the first high inte ity rainfall event, a pulse (2.1 μg L-1) of atrazine leached through tilled cores while leaching rate was linear and decreased (1.25 to 0.9 μg L-1) through un-tilled cores. Leaching rate was linear for both the tilled and un-tilled cores during the second rain. Less atrazine was left in the surface 5 cm of tilled soil than un-tilled after the two rains. Results confirmed field observations and suggested that when tillage is reversed on well structured soils, pesticide leaching may increase relative to un-tilled soil but these effects are probably confined to the first rain events after application only.     

Design and optimization of a hybrid process based on hollow-fiber membrane/coagulation for wastewater treatment

Environmental Science and Pollution Research - Treatment of textile wastewater using ultrafiltration membranes was carried out in this study. Since membrane fouling is a major operational problem...     

Health risk assessment of potentially toxic elements intake via food crops consumption: Monte Carlo simulation-based probabilistic and heavy metal pollution index

Environmental Science and Pollution Research - The aim of this study is to assess the content of heavy metals and their potential health risk in consumed food crops. To this end, the samples from...