Multi-criteria decision-making for prioritizing photocatalytic processes followed by TiO2-MIL-53(Fe) characterization and application for diazinon removal.

Multi-criteria decision-making (MCDM) can introduce the best option based on evidence. We integrated the Analytic Hierarchy Process (AHP) and the Technique for Order of Preference by Similarity to the Ideal Solution (TOPSIS) to prioritize the alternatives for photocatalytic diazinon removal in a bench scale and characterized TiO2-MIL-53(Fe) for this purpose. Criteria and alternatives were listed based on systematic literature reviews and expert opinions. Then, AHP and TOPSIS questionnaires were developed and distributed to an expert panel for pairwise comparisons. We converted the linguistic variables into the corresponding fuzzy values and used R for mathematical calculations. Then, TiO2-MIL-53(Fe) was synthesized and characterized for diazinon removal under LED visible light. The AHP ranked criteria as availability > degradation efficiency > safety for the environment > material cost > energy consumption > mineralization efficiency > photocatalyst reusability > safety for personnel > equipment cost. Based on TOPSIS, the order of alternatives was TiO2-containing/Visible light > ZnO-containing/UV light > TiO2-containing/UV light > ZnO-containing/Visible light > WO3-containing/UV light. With a bandgap of 1.8 eV, TiO2-MIL-53(Fe) could remove 89.35% of diazinon at 10 mg/L diazinon concentration, 750 mg/L catalyst dose, pH 6.8, and 180-min reaction time. Hybrid AHP-TOPSIS identified the best option for photocatalytic diazinon removal from aqueous solutions. Thus, MCDM techniques can use systematic review results to overcome the uncertainty in designing experimental studies.

Photocatalytic removal of diazinon from aqueous solutions: a quantitative systematic review.

Diazinon is a widely used pesticide that can be effectively degraded in aqueous solutions via photocatalytic oxidation. This quantitative systematic review was conducted to shed light on the various aspects of photocatalytic diazinon removal based on evidence. A systematic search was performed in Scopus, PubMed, Web of Science, Embase, and Ovid databases with keywords including diazinon, photocatalysis, and their equivalents. The search was limited to original articles in English published between January 1, 2010, and March 25, 2021. The results were expressed by descriptive statistics including mean, SD, median, and percentiles, among others. The initial electronic and manual search retrieved 777 articles, among which 41 studies comprising 49 trials were qualified for data synthesis. The reported diazinon degradation rate ranged from 2 to 100%, with a mean ± SD of 59.17 ± 28.03%. Besides, ZnO/UV, WO3/UV, TiO2/UV, and TiO2/Vis, in sequence, were the most widely used processes with the highest efficacies. Solution pH in the range of 5-8, catalyst dose below 600 mg/L, diazinon initial concentration below 40 mg/L, and contact time of 20-140 min could be the optimum conditions. Diazinon degradation obeyed the first-order kinetic model with kobs between 0.0042 and 1.86 min-1 and consumed energy of 38.93-350.36 kWh/m3. Diazoxon and IMP were the most detected by-products of diazinon degradation although bioassay data were scarce. Based on the results, photocatalytic processes are very efficient in removing diazinon from aqueous solutions although more elaborate studies are needed to assess the mineralization rate and effluent toxicity.

Iron-modified activated carbon derived from agro-waste for enhanced dye removal from aqueous solutions.

BACKGROUND AND AIM: Finding a cost-effective adsorbent can be an obstacle to large-scale applications of adsorption. This study used an efficient activated carbon adsorbent based on agro-waste for dye removal. METHODS: Pistachio shells as abundant local agro-wastes were used to prepare activated carbon. Then, it was modified with iron to improve its characteristics. Acid red 14 was used as a model dye in various conditions of adsorption (AR14 concentration 20-150 mg L-1, pH 3-10, adsorbent dosage 0.1-0.3 g L-1, and contact time 5-60 min). RESULTS: A mesoporous adsorbent was prepared from pistachio shells with 811.57 m2 g-1 surface area and 0.654 cm3 g-1 pore volume. Iron modification enhanced the characteristics of activated carbon (surface area by 33.3% and pore volume by 64.1%). Adsorption experiments showed the high effectiveness of iron-modified activated carbon for AR14 removal (>99%, >516 mg g-1). The adsorption followed the pseudo-second kinetic model (k = 0.0005 g mg-1 min-1) and the Freundlich isotherm model (Kf = 152.87, n = 4.61). Besides, the reaction occurred spontaneously (ΔG0 = -36.65 to -41.12 kJ mol-1) and was exothermic (ΔH0 = -41.86 kJ mol-1 and ΔS0 = -3.34 J mol-1 K-1). CONCLUSION: Iron-modified activated carbon derived from pistachio shells could be cost-effective for the treatment of industrial wastewater containing dyes.

Relationship of fluoride in drinking water with blood pressure and essential hypertension prevalence: a systematic review and meta-analysis.

BACKGROUND AND OBJECTIVE: Previous studies showed controversial results of the relationship between fluoride exposure through drinking water and elevated blood pressure. We conducted a systematic review and meta-analysis to assess the direct relationship of drinking water fluoride exposure with blood pressure and essential hypertension prevalence in general populations. METHODS: We conducted a systematic search in databases including Web of Knowledge, PubMed, Scopus, and Embase by MeSH and non-MeSH terms for relevant studies with any design published until August 2019, with no limitation in time and language. The pooled effect measure was calculated within a 95% confidence interval (CI). RESULTS: Our search retrieved 630 journal articles, six of which were eligible for data extraction. The random-effects model found significantly higher systolic blood pressure (mean difference = 6.49 mmHg; 95% CI 3.73-9.25; p value < 0.01) and diastolic blood pressure (mean difference = 4.33 mmHg; 95% CI 1.39-7.26; p value < 0.01) in groups exposed to high-fluoride drinking water than in groups exposed to normal/low-fluoride drinking water. A significant relationship was also found between high-fluoride drinking water and essential hypertension (odds ratio = 2.14; 95% CI 1.02-4.49; p value = 0.045). CONCLUSION: The risk of elevated blood pressure increases in the general population of fluoride endemic areas. However, more research is needed to make a firm conclusion about the adverse effects of excess fluoride intake on the cardiovascular system at the individual level.

Association of suicide with short-term exposure to air pollution at different lag times: A systematic review and meta-analysis.

BACKGROUND: Suicide is a major public health problem, with some environmental risk factors. OBJECTIVES: This meta-analysis study explored the association between short-term exposure to air pollution and suicide mortality, with an emphasis on different lag times. METHODS: A systematic search was used to find relevant studies in databases including Scopus, Web of Knowledge, Pubmed, and Embase published up to 19 May 2020. The inclusion criteria included case-crossover or time-series studies assessing the association of criteria air pollutants with suicide mortality at different Lag Days of 0-7 (LD0 to LD7) and Cumulative Lags of 1-7 days (CL1 to CL7). Odds ratios (OR) were calculated with 95% confidence intervals (CI). RESULTS: Of 1436 retrieved articles, 11 were eligible for data extraction, representing data on 283,550 suicides published between 2010 and 2019. The odds of suicide death increase with each 10 µg/m3 increase in the mean concentrations of NO2 at CL1 (1.013: 1.006-1.021), CL2 (1.028: 1.003-1.053), CL3 (1.035: 1.001-1.070), and LD2 (1.011: 1.001-1.022), SO2 at CL1 (1.024: 1.014-1.034), CL2 (1.030: 1.012-1.048), CL3 (1.029: 1.009-1.049), and CL4 (1.027: 1.005-1.049), O3 at CL6 (1.008: 1.000-1.016), PM10 at CL1 (1.004: 1.000-1.008), and PM2.5 at CL1 (1.017: 1.003-1.031). Besides, the odds of suicide death increases with each 0.5 mg/m3 increase in the mean concentration of CO at LD6 (1.005: 1.000-1.011). However, it decreased with increased O3 exposure at LD3 (0.997: 0.994-1.000). CONCLUSION: The study supports a positive association between air pollution and suicide mortality. No immediate risk was elucidated but the possible effects seem to be exerted cumulatively.

The effect of gas versus charcoal open flames on the induction of polycyclic aromatic hydrocarbons in cooked meat: a systematic review and meta-analysis.

PURPOSE: Open flames of gas and charcoal can induce polycyclic aromatic hydrocarbons (PAHs) in cooked meat. The current study aimed to compare the effect of gas and charcoal open flames on the induction of PAHs in cooked meat using a meta-analysis approach. METHODS: A systematic review of the literature was conducted electronically based on the PRISMA guidelines. Experimental studies comparing the PAHs content of cooked meat over open flames of gas and charcoal were searched using the appropriate keywords until June 2018. RESULTS: Of 1137 papers retrieved, 7 with a total sample size of 474 meat samples were used in the meta-analysis. The mean difference (MD) between the gas and charcoal cooking methods in the induction of each PAH was 2.053 µg/Kg. (95%CI: 1.022-3.085 µg/Kg; P < 0.001). The subgroup analysis of 17 trials indicated the difference between the two cooking methods increases when red meat rather than white meat is cooked (MD in red meat: 3.499 µg/Kg; 95%CI: 2.030-4.967; P < 0.0001 vs. MD in white meat: 3.319 µg/Kg; 95% CI: 1.689-4.950; P < 0.0001). Interestingly, studies that analyzed meat samples for fewer PAHs (cut-off ≤7) found a much wider difference between gas and charcoal-cooked meat (MD: 5.106 µg/Kg; (95% CI: 2.162-8.049; P < 0.001 in studies with ≤7 PAHs vs. MD: 1.447 µg/Kg; 95% CI: 0.628-2.266; P < 0.001 in studies with >7 PAHs). CONCLUSIONS: It is necessary to avoid open flames of charcoal as the heat source or change the geometry of charcoal-fired cookstoves to prevent fat dripping on the fire and thus, excessive PAHs induction.

Relationship between suicide mortality and lithium in drinking water: A systematic review and meta-analysis.

BACKGROUND: Lithium at therapeutic doses has protective effects against suicide in clinical practice. This meta-analysis aimed to investigate the relationship between lithium concentration in drinking water and suicide mortality in the general population. METHODS: A systematic search was conducted in Web of Knowledge, PubMed, ScienceDirect, and Scopus to find papers reporting the crude relationship between drinking water lithium and suicide incidence in the general population until June 2019. The pooled effect measure was expressed as odds ratio (OR) and 95% confidence interval (CI) using the random-effects model. RESULTS: We retrieved 308 English original articles, of which 13 ecologic studies with a total sample size of 939 regions and one cohort study with a sample size of 3,740,113 people were eligible for the meta-analysis. A significant relationship was found between the lithium concentration in drinking water and reduced suicide mortality (OR= 0.42; 95% CI: 0.27-0.67; p-value <0.01). Ten studies reported gender-specific responses to lithium, with the pooled estimates as follows: OR= 0.54; 95% CI: 0.35-0.84; p-value <0.01 for men, OR= 0.70; 95% CI: 0.48-1.01; p-value =0.057 for women, and OR= 0.63; 95% CI: 0.47-0.83; p-value <0.01 for total. LIMITATIONS: The study was limited to the assessment of the crude relationship between lithium exposure and suicide rate without considering the role of confounders. CONCLUSIONS: Lithium in drinking water is dose-dependently associated with reduced suicide mortality at least in ecological studies. However, we need well-designed clinical trials to confirm the protective effect of drinking water lithium intake against suicide.