Dry Biosolids Reuse as Costless Biodegradable Adsorbent for Cadmium Removal from Water Systems

The recycling of untreated dry biosolids, as costless biodegradable adsorbent for the removal of cadmium from aqueous phase was characterized. The adsorption of cadmium was reported to depend on initial pH, adsorbent dose, agitation time, and initial Cd concentration. The results of the batch experiments revealed that the maximum adsorption capacity of the untreated dry biosolids was 39.22 mg g-1 under optimum operating conditions (i.e. pH: 5, adsorbent dose: 2 g l-1, contact time: 16h). Adsorption reaches equilibrium after 16h, which can be attributed to both external surface adsorption (R2 = 0.86) and intraparticle dif usion (R2 = 0.98). The Langmuir isotherm model best described cadmium adsorption (R2 = 0.99) and the pseudo-second-order kinetic model was obeyed, suggesting that the mechanism involved was chemisorption. Biodegradability would make the recovery of adsorbed Cd an environmentally friendly process. Comparing the obtained findings with the related published results, it can be concluded that treating biosolids might be an unnecessary and costly procedure for recycling biosolids as an adsorbent for cadmium

Bioremediation of cadmium-contaminated water systems using intact and alkaline-treated alga (<i>Hydrodictyon reticulatum</i>) naturally grown in an ecosystem

<p>Cadmium can enter water, soil, and food chain in amounts harmful to human health by industrial wastes. The use of intact and NaOH-treated dried algal tissues (<i>Hydrodictyon reticulatum</i>), a major ecosystem bio-component, for Cd removal from aqueous solutions was characterized. Cadmium biosorption was found to be dependent on solution pH, bioadsorbent dose, the interaction between pH and dose, contact time, and initial Cd concentration. The experimental results indicated that the biosorption performance of alkaline-treated algal tissues was better than that of intact tissues. The maximum biosorption capacities were 7.40 and 12.74 mg g⁻¹ for intact and alkaline-treated bioadsorbents, respectively, at optimum operating conditions. Biosorption reaches equilibrium after 24 and 240 minutes of contact, respectively, for alkaline-treated and intact bioadsorbents. Cadmium biosorption was best fitted to Langmuir isotherm model (<i>R²</i> ≈ 0.99) and the kinetic study obeyed the pseudo-second-order kinetic model, which suggests chemisorption as the rate-limiting step in the biosorption process. Alkaline-treated algal tissues can be used as a new material of low-cost bioadsorbent for continuous flow rate treatment systems.</p

International Nosocomial Infection Control Consortium report, data summary of 50 countries for 2010-2015: Device-associated module

•We report INICC device-associated module data of 50 countries from 2010-2015.•We collected prospective data from 861,284 patients in 703 ICUs for 3,506,562 days.•DA-HAI rates and bacterial resistance were higher in the INICC ICUs than in CDC-NHSN's.•Device utilization ratio in the INICC ICUs was similar to CDC-NHSN's. Background: We report the results of International Nosocomial Infection Control Consortium (INICC) surveillance study from January 2010-December 2015 in 703 intensive care units (ICUs) in Latin America, Europe, Eastern Mediterranean, Southeast Asia, and Western Pacific. Methods: During the 6-year study period, using Centers for Disease Control and Prevention National Healthcare Safety Network (CDC-NHSN) definitions for device-associated health care-associated infection (DA-HAI), we collected prospective data from 861,284 patients hospitalized in INICC hospital ICUs for an aggregate of 3,506,562 days. Results: Although device use in INICC ICUs was similar to that reported from CDC-NHSN ICUs, DA-HAI rates were higher in the INICC ICUs: in the INICC medical-surgical ICUs, the pooled rate of central line-associated bloodstream infection, 4.1 per 1,000 central line-days, was nearly 5-fold higher than the 0.8 per 1,000 central line-days reported from comparable US ICUs, the overall rate of ventilator-associated pneumonia was also higher, 13.1 versus 0.9 per 1,000 ventilator-days, as was the rate of catheter-associated urinary tract infection, 5.07 versus 1.7 per 1,000 catheter-days. From blood cultures samples, frequencies of resistance of Pseudomonas isolates to amikacin (29.87% vs 10%) and to imipenem (44.3% vs 26.1%), and of Klebsiella pneumoniae isolates to ceftazidime (73.2% vs 28.8%) and to imipenem (43.27% vs 12.8%) were also higher in the INICC ICUs compared with CDC-NHSN ICUs. Conclusions: Although DA-HAIs in INICC ICU patients continue to be higher than the rates reported in CDC-NSHN ICUs representing the developed world, we have observed a significant trend toward the reduction of DA-HAI rates in INICC ICUs as shown in each international report. It is INICC's main goal to continue facilitating education, training, and basic and cost-effective tools and resources, such as standardized forms and an online platform, to tackle this problem effectively and systematically