Impact of combining chlorine dioxide and chlorine on DBP formation in simulated indoor swimming pools.

J Environ Sci (China)

Department of Environmental Engineering and Earth Sciences, Clemson University, Anderson, SC 29625, USA. Electronic address:

Published: August 2017

The main objective of this study was to assess the combined use of chlorine dioxide (ClO) and chlorine (Cl) on the speciation and kinetics of disinfection by-product (DBP) formation in swimming pools using synthetic pool waters prepared with a body fluid analog (BFA) and/or fresh natural water. At 1:25 (mass ratio) of ClO to Cl, there was no significant reduction in the formation of trihalomethanes (THMs) and haloacetic acids (HAAs) for both BFA solution and natural water compared to the application of Cl alone. When the mass ratio of ClO to Cl increased to 1:1, substantial decreases in both THMs and HAAs were observed in the natural water, while there was almost no change of DBP formations in the BFA solution. Haloacetonitriles and halonitromethanes levels in both water matrices remained similar. In the presence of bromide, the overall DBP formation increased in both BFA solution and natural water. For the DBP formation kinetics, after 72hr of contact time, very low formation of THMs and HAAs was observed for the use of ClO only. Compared to Cl control, however, applying the 1:1 mixture of ClO/Cl reduced THMs by >60% and HAAs by >50%. Chlorite was maintained below 1.0mg/L, while the formation of chlorate significantly increased over the reaction time. Finally, in a bench-scale indoor pool experiment, applying ClO and Cl simultaneously produced less THMs compared to Cl control and kept chlorite at <0.4mg/L, while HAAs and chlorate accumulated over 4-week operation period.

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jes.2017.04.020DOI Listing

Publication Analysis

Top Keywords

dbp formation
16
natural water
16
bfa solution
12
chlorine dioxide
8
swimming pools
8
mass ratio
8
ratio clo
8
solution natural
8
thms haas
8
haas observed
8

Similar Publications

Mitochondria are key regulators of metabolism and ATP supply in skeletal muscle, while circadian rhythms influence many physiological processes. However, whether mitochondrial function is intrinsically regulated in a circadian manner in mouse skeletal muscle is inadequately understood. Accordingly, we measured post-absorptive transcript abundance of markers of mitochondrial biogenesis, dynamics, and metabolism (extensor digitorum longus [EDL], soleus, gastrocnemius), protein abundance of electron transport chain complexes (EDL and soleus), enzymatic activity of SDH (tibialis anterior and plantaris), and maximum uncoupled respiration (tibialis anterior) in different skeletal muscles from female C57BL/6NJ mice at four zeitgeber times (ZT), ZT 1, 7, 13, and 19.

View Article and Find Full Text PDF

Purpose: To evaluate the effect of osilodrostat and hypercortisolism control on blood pressure (BP) and glycemic control in patients with Cushing's disease.

Methods: Pooled analysis of two Phase III osilodrostat studies (LINC 3 and LINC 4), both comprising a 48-week core phase and an optional open-label extension. Changes from baseline in systolic and diastolic BP (SBP and DBP), fasting plasma glucose (FPG), and glycated hemoglobin (HbA) were evaluated during osilodrostat treatment in patients with/without hypertension or diabetes at baseline.

View Article and Find Full Text PDF

A novel exercise protocol for cardiac rehabilitation aerobic (CRA) has been developed by Hebei Sport University, demonstrating efficacy in patients with coronary heart disease (CHD). The objective of this study was to evaluate the impact of CRA on precise cardiac rehabilitation (CR) for CHD patients presenting with stable angina pectoris. The study cohort comprised patients with stable angina who were categorized into three groups: the CRA group (n = 35), the power bicycles (PB) group (n = 34), and the control group (n = 43).

View Article and Find Full Text PDF

This study assessed the therapeutic effectiveness of a single-pill combination (SPC) of olmesartan/amlodipine plus rosuvastatin for blood pressure (BP) and low-density lipoprotein cholesterol (LDL-C) in patients with hypertension and dyslipidemia. Adult patients with hypertension and dyslipidemia who were decided to be treated with the study drug were eligible. The primary endpoint was the proportion of patients who achieved BP, LDL-C and both BP and LDL-C treatment goals at weeks 24-48.

View Article and Find Full Text PDF

Aim: The aim of the study is to determine the effect of anti-inflammatory biological drugs (adalimumab, infliximab and rituximab) on the cardiovascular system during the treatment of patients with rheumatoid arthritis.

Methods: Involved in research 70 women aged 18 to 60 years with a confirmed diagnosis of rheumatoid arthritis (diagnosis confirmed by the American College of Rheumatology 2010 (ACR) and European League of Rheumatology (EULAR) classification criteria). Patients on standard treatment and biological drugs were divided into 3 groups, and the third group was divided into two subgroups.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!