The influence of chlorine in indoor swimming pools on the composition of breathing phase of professional swimmers

OBJECTIVES

Swimming is one of the most popular forms of physical activity. Pool water is cleaned with chlorine, which - in combination with compounds contained in water - could form chloramines and trichloromethane in the swimmer's lungs. The aim of the present study was to examine the effect of swimming training in an indoor pool on the composition of swimmers' respiratory phase metabolomics, and develop a system to provide basic information about its impact on the swimmer's airway mucosa metabolism, which could help to assess the risk of secondary respiratory tract diseases i.e. sport results, condition, and health including lung acute and chronic diseases).

DESIGN

A group of competitive swimmers participated in the study and samples of their respiratory phase before training, immediately after training, and 2 h after training were assessed.

METHODS

Sixteen male national and international-level competitive swimmers participated in this study. Respiratory phase analysis of the indoor swimming pool swimmers was performed. Gas chromatography combined with mass spectrometry (GCMS) was used in the measurements. All collected data were transferred to numerical analysis for trends of tracking and mapping. The breathing phase was collected on special porous material and analyzed using GCMS headspace.

RESULTS

The obtained samples of exhaled air were composed of significantly different metabolomics when compared before, during and after exercise training. This suggests that exposition to indoor chlorine causes changes in the airway mucosa.

CONCLUSION

This phenomenon may be explained by occurrence of a chlorine-initiated bio-reaction in the swimmers' lungs. The obtained results indicate that chromatographic exhaled gas analysis is a sensitive method of pulmonary metabolomic changes assessment. Presented analysis of swimmers exhaled air indicates, that indoor swimming may be responsible for airway irritation caused by volatile chlorine compounds and their influence on lung metabolism.

Metabolic Insights into the Anion-Anion Antagonism in Sweet Basil: Effects of Different Nitrate/Chloride Ratios in the Nutrient Solution

Sweet basil (Ocimum basilicum L.) is a highly versatile and globally popular culinary herb, and a rich source of aromatic and bioactive compounds. Particularly for leafy vegetables, nutrient management allows a more efficient and sustainable improvement of crop yield and quality. In this work, we investigated the effects of balanced modulation of the concentration of two antagonist anions (nitrate and chlorine) in basil. Specifically, we evaluated the changes in yield and leaf metabolic profiles in response to four different NO3-:Cl- ratios in two consecutive harvests, using a full factorial design. Our work indicated that the variation of the nitrate-chloride ratio exerts a large effect on both metabolomic profile and yield in basil, which cannot be fully explained only by an anion-anion antagonist outcome. The metabolomic reprogramming involved different biochemical classes of compounds, with distinctive traits as a function of the different nutrient ratios. Such changes involved not only a response to nutrients availability, but also to redox imbalance and oxidative stress. A network of signaling compounds, including NO and phytohormones, underlined the modeling of metabolomic signatures. Our work highlighted the potential and the magnitude of the effect of nutrient solution management in basil and provided an advancement towards understanding the metabolic response to anion antagonism in plants.

Exhaled nitric oxide as a marker of chlorine exposure in young asthmatic swimmers

BACKGROUND

Swimming is recommended for people with asthma. However, the inevitable exposure to chlorine and its disinfectant byproducts in indoor swimming pools could be responsible for bronchial inflammation and asthma development. Fractional exhaled nitric oxide (FeNO) is a noninvasive marker of airway inflammation that predicts asthma exacerbations.

OBJECTIVES

To evaluate pretraining and posttraining FeNO levels in young swimmers with asthma attending an indoor chlorinated pool compared with a set of healthy swimmers and to examine the potential risk of exposure to chlorine as a factor associated with bronchial inflammation.

METHODS

A total of 146 children (8-18 years old) constantly attending an indoor chlorinated swimming pool were enrolled. Spirometry and FeNO measurements were performed 30 minutes after their arrival at the pool and immediately after exercise. Pre-exercise and postexercise spirometric and FeNO levels were assessed in a random subgroup of 14 swimmers (10 with asthma and 4 without) who performed cardiopulmonary exercise testing.

RESULTS

Asthma was detected in 23 swimmers. In swimmers with asthma, preswimming FeNO values were significantly elevated compared with swimmers without asthma and their FeNO values measured before cardiopulmonary exercise testing. Postexercise FeNO values were significantly decreased by approximately one-third in healthy children and children with asthma in all sporting backgrounds. However, postswimming FeNO values remained significantly higher in swimmers with asthma compared with those without asthma. Forced expiratory volume in 1 second (FEV₁), forced vital capacity (FVC), and FEV₁/FVC ratio values showed no significant difference before and after 2 types of activity.

CONCLUSION

Elevated FeNO levels before and after swimming were recorded in swimmers with asthma not observed in a different exercise field. The presence of chlorine in the indoor swimming pool seems to explain this finding.

Influence of chlorinated water on the development of allergic diseases - An overview

Indoor swimming pools can be used all year round and serve for one of the most popular sport pursued for recreation. The positive effect of swimming arises in particular from the involvement of all the muscles of the body, decreasing the burden on the joints, as well as functional improvement of both the lungs and heart. Chlorine is typically used to disinfect swimming pool water and as a result the changes that take place lead to the formation of by-products, such as monochloramines (NH₂Cl), dichloramines (NH₂Cl₂) i trichloramines (NH₂Cl₃), trihalogenometans (THM) or haloacetic acid (HAA). The highest concentration of these substances is just above the water surface and they may cause irritation of skin, eyes and mucosa of the respiratory tract. The toxic effect of high chlorine concentration and its side-products on the respiratory system is known, but the effect of low concentrations of these compounds is still not fully determined. Recent studies suggest that development of allergic diseases among swimmers may be increased by epithelial disorders driven by airway barrier dysfunction caused by chlorine irritation. Swimming in chlorinated water may be linked to symptoms of bronchial hyperreactivity, asthma and rhinitis especially in children, elite swimmers and employees of indoor swimming pools. Hypersensivity pneumonitis related to the use of swimming pools may manifest as a swimming pool or sauna user lung, most commonly caused by water polluting pathogens. The article summarizes recent data concerning the influence of chlorinated water on the development of allergic diseases.

Chlorine gas inhalation manifesting with severe acute respiratory distress syndrome successfully treated by high-volume hemofiltration: A case report

RATIONALE

There have been occasional reports of respiratory dysfunction associated with acute chlorine gas inhalation. However, management of acute chlorine-related inhalation injury is largely empirical, supportive, and sometimes challenging.

PATIENT CONCERNS

A 43-year-old man was transferred to the emergency department because of accidental chlorine inhalation and rapidly progressive dyspnea.

DIAGNOSES

The patient was diagnosed with acute respiratory distress syndrome due to chlorine gas exposure.

INTERVENTIONS

Because this patient had failed on conventional treatments including mechanical ventilation and high-dose intravenous corticosteroid therapy, we applied high-volume hemofiltration (HVHF).

OUTCOMES

The patient recovered quickly after four sessions of HVHF and was discharged uneventfully on day 28.

LESSONS

HVHF is a potential method for improvement of chlorine-induced acute respiratory failure and worsening hypoxemia.

Inhalational Chlorine Injuries at Public Aquatic Venues - California, 2008-2015

In June 2015, personnel from California's Contra Costa Health Services Environmental Health and Hazardous Materials (hazmat) divisions were alerted to a possible chemical release at a swimming pool in an outdoor municipal water park. Approximately 50 bathers were in the pool when symptoms began; 34 (68%) experienced vomiting, coughing, or eye irritation. Among these persons, 17 (50%) were treated at the scene by Contra Costa's Emergency Medical Services (EMS) and released, and 17 (50%) were transported to local emergency departments; five patients also were evaluated later at an emergency department or by a primary medical provider. Environmental staff members determined that a chemical controller malfunction had allowed sodium hypochlorite and muriatic acid (hydrochloric acid) solutions to be injected into the main pool recirculation line while the recirculation pump was off; when the main recirculation pump was restarted, toxic chlorine gas (generated by the reaction of concentrated sodium hypochlorite and muriatic acid) was released into the pool. A review of 2008-2015 California pesticide exposure records identified eight additional such instances of toxic chlorine gas releases at public aquatic venues caused by equipment failure or human error that sickened 156 persons. Chemical exposures at public aquatic venues can be prevented by proper handling, storage, and monitoring of pool chemicals; appropriate equipment operation and maintenance; training of pool operators and staff members on pool chemical safety; and reporting of chemical exposures.

Association between domestic water hardness, chlorine, and atopic dermatitis risk in early life: A population-based cross-sectional study

BACKGROUND

Domestic water hardness and chlorine have been suggested as important risk factors for atopic dermatitis (AD).

OBJECTIVE

We sought to examine the link between domestic water calcium carbonate (CaCO3) and chlorine concentrations, skin barrier dysfunction (increased transepidermal water loss), and AD in infancy.

METHODS

We recruited 1303 three-month-old infants from the general population and gathered data on domestic water CaCO3 (in milligrams per liter) and chlorine (Cl2; in milligrams per liter) concentrations from local water suppliers. At enrollment, infants were examined for AD and screened for filaggrin (FLG) skin barrier gene mutation status. Transepidermal water loss was measured on unaffected forearm skin.

RESULTS

CaCO3 and chlorine levels were strongly correlated. A hybrid variable of greater than and less than median levels of CaCO3 and total chlorine was constructed: a baseline group of low CaCO3/low total chlorine (CaL/ClL), high CaCO3/low total chlorine (CaH/ClL), low CaCO3/high total chlorine (CaL/ClH) and high CaCO3/high total chlorine (CaH/ClH). Visible AD was more common in all 3 groups versus the baseline group: adjusted odds ratio (AOR) of 1.87 (95% CI, 1.25-2.80; P = .002) for the CaH/ClL group, AOR of 1.46 (95% CI, 0.97-2.21; P = .07) for the CaL/ClH, and AOR of 1.61 (95% CI, 1.09-2.38; P = .02) for the CaH/ClH group. The effect estimates were greater in children carrying FLG mutations, but formal interaction testing between water quality groups and filaggrin status was not statistically significant.

CONCLUSIONS

High domestic water CaCO3 levels are associated with an increased risk of AD in infancy. The influence of increased total chlorine levels remains uncertain. An intervention trial is required to see whether installation of a domestic device to decrease CaCO3 levels around the time of birth can reduce this risk.

Off the rails in rural South Carolina: a qualitative study of healthcare provider perspectives on the long-term health impact of the Graniteville train disaster

INTRODUCTION

In 2005, a train derailment and subsequent chlorine spill ravaged the rural town of Graniteville in South Carolina, resulting in one of the worst chlorine gas exposures in US.

HISTORY

Significant health and economic challenges persist in the community more than a decade later. Healthcare providers offered healthcare services to community members in the immediate aftermath of the disaster, and many still live in the community and continue to provide healthcare services. As such, healthcare professionals provide a unique and important perspective to help understand the impact of the disaster on the community's health. The purpose of this study was to explore healthcare providers' perspectives about the long-term effects of the disaster on community health, healthcare access, and wellbeing.

METHODS

Semi-structured interviews were conducted with 30 healthcare providers who treated survivors of the Graniteville train disaster. A qualitative, essentialist, inductive thematic analytic approach was used to analyze study data.

RESULTS

Four themes emerged regarding the disaster's long-term impact: effects of chlorine exposure on physical health, issues with healthcare access, residual effects of the disaster on personal and community wellbeing, and improving health and community wellbeing.

CONCLUSIONS

Disaster recovery should not be considered solely an acute event; agencies must be prepared for long-term, potentially chronic ailments, particularly in underserved, rural communities. Efforts to address the long-term health needs of communities post-disaster should consider the perspectives of healthcare providers to offer a well-rounded assessment of community needs. Study findings can help inform future disaster response strategies in communities locally and globally.

Photovoice: Assessing the Long-Term Impact of a Disaster on a Community's Quality of Life

Photovoice is a qualitative method of inquiry whereby individuals can document their lived experiences, particularly individuals whose voices are not typically heard in regard to promoting social change and policy development. We used photovoice to elicit major themes regarding community members' perceptions of the long-term impact on their quality of life as a deadly technological disaster hit a small, rural town in South Carolina. Overall, participants photographed more negative images than positive. Overarching themes included residential and business vacancies, economic decline, the need for clean-up and modernization, attention to wellness or rehabilitation, and concerns for safety. Emergency response agencies should consider the themes elicited from these community residents to help identify where to focus disaster response efforts both in the immediate aftermath and during the long-term recovery period of technological disasters, particularly in underserved, rural communities.

Top five chemicals resulting in injuries from acute chemical incidents—Hazardous Substances Emergency Events Surveillance, nine states, 1999-2008

PROBLEM/CONDITION

The Toxic Substances Control Act Chemical Substance Inventory lists >84,000 chemicals used in commerce (http://www.epa.gov/oppt/existingchemicals/pubs/tscainventory/basic.html). With chemicals having a multitude of uses, persons are potentially at risk daily for exposure to chemicals as a result of an acute chemical incident (lasting <72 hours). Depending on the level of exposure and the type of chemical, exposure can result in morbidity and, in some cases, mortality.

REPORTING PERIOD

1999-2008.

DESCRIPTION OF SYSTEM

The Hazardous Substances Emergency Events Surveillance (HSEES) system was operated by the Agency for Toxic Substances and Disease Registry during January 1991-September 2009 to collect data that would enable researchers to describe the public health consequences of chemical incidents and to develop activities aimed at reducing the harm from such incidents. This report identifies the top five chemicals that caused injuries in the nine states (Colorado, Iowa, Minnesota, New York, North Carolina, Oregon, Texas, Washington, and Wisconsin) that participated in HSEES during its last 10 full years of data collection (1999-2008).

RESULTS

Of the 57,975 incidents that were reported, 54,989 (95%) involved the release of only one chemical. The top five chemicals associated with injury were carbon monoxide (2,364), ammonia (1,153), chlorine (763), hydrochloric acid (326), and sulfuric acid (318). Carbon monoxide and ammonia by far caused the most injuries, deaths, and evacuations. Chlorine, while not in the top 10 chemicals released, was in the top five chemicals associated with injury because of its hazardous properties.

INTERPRETATION

Multiple measures can be taken to prevent injuries associated with the top five chemicals. Because many carbon monoxide releases occur in residential settings, use of carbon monoxide detectors can prevent injuries. Substituting chemicals with less lethal alternatives can result in mitigating injuries associated with ammonia. Routine maintenance of equipment and engineering controls can reduce injuries associated with chlorine and sulfuric acid, and proper chemical handling training can reduce injuries associated with hydrochloric acid. PUBLIC HEALTH IMPLICATIONS: Understanding the most frequently reported locations where carbon monoxide, ammonia, chlorine, hydrochloric acid, and sulfuric acid are released along with the most frequently reported contributing factors can help mitigate injuries associated with these releases. Prevention initiatives should focus on educating the public and workers about the dangers of these chemicals and about proper handling of these chemicals along with routine maintenance of equipment.

Mutagenicity and genotoxicity of water treated for human consumption induced by chlorination by-products

Water used for human consumption may contain mutagens and carcinogens generated during the disinfection process with chlorine. In the study described in this article, the mutagenicity and genotoxicity of water samples taken from the San Cristobal treatment plant in Medellin, Colombia, were evaluated. Short-term mutagenic and genotoxic assays using the Ames test and comet assay, respectively, were employed to examine the genotoxic activity of the extracts of these water samples. Two samples were taken before and after the chlorination process. The treated water samples without chlorination did not show mutagenic effects using the Ames test, while the chlorinated samples produced mutagenic activity in both strains. A dose-response relationship for the comet assay was obtained only in the chlorinated samples. MX (3-chloro-4-[dichloromethyl]-5-hydroxy-2[5H]-furanone), E-MX ([E]-2-chloro-3-[dichloromethyl]-4-oxobutenoic acid), and some trihalomethanes were detected at low concentrations. These concentrations were enough, however, to cause detectable mutagenic and genotoxic activity in the extracts of chlorinated water samples.

Cancer incidence in a chlorochemical plant in Isère, France: an occupational cohort study, 1979-2002

BACKGROUND

A major French chlorine chemical plant (chlor-alkali process with diaphragm cell and manufacturing of organochlorine chemicals) has used or produced known or suspected carcinogenic compounds.

METHODS

A cohort study, based on the plant occupational health service and the regional cancer registry, analyzed the standardized incidence ratios of malignant tumors for the period 1979-2002. Individual exposures were estimated from workers' occupational histories in a dual division of jobs into 9 sectors and 115 workshops with known exposures.

RESULTS

Men (2,742) were followed, corresponding to 52,794 person-years. Primary tumors (304) were observed for 290 expected cases, a non-significant 5% excess. A significant excess was found of pleural mesothelioma and bladder cancer in employees hired before 1964.

CONCLUSION

Excesses of mesothelioma and bladder cancer were found, whereas there was no excess of hematopoietic cancers despite high benzene and dioxin exposures. Surprisingly, mesothelioma cases did not include workers who were the most exposed to asbestos.

[Psycho-emotional state of workers engaged into chlorine and soda production through electrolysis with mercury-pool cathode]

Workers engaged into the studied production are exposed to occupational factors complex as vapor, gas and aerosol mixture. Metallic mercury vapors and its compounds exceed MAC over 10 times in this mixture, noise level at the enterprise is 10 dB over the maximal allowable level, general vibration is 8 dB over the MAL, the occupational hazards also include unfavorable microclimate, work hardiness and intensity. Psychoemotional state of the workers demonstrate significantly disordered emotions and will, premorbid personality changes, lower memory and attention level, indisposition and mood changes, increased reactive and personal anxiety, decreased performance level. Informative parameter in occupational examination of workers is memory and attention level evaluation.

Airway remodeling and inflammation in competitive swimmers training in indoor chlorinated swimming pools

BACKGROUND

Airway disorders are common in regular chlorinated swimming pool attendees, particularly competitive athletes, but the impact of intense swimming training on airway function and structure remains unclear.

OBJECTIVE

This study aimed to evaluate airway inflammation and remodeling in elite swimmers.

METHODS

Twenty-three elite swimmers were tested during off-training season. All had exhaled nitric oxide measurement, methacholine test, eucapnic voluntary hyperpnea challenge, allergy skin prick tests, and bronchoscopy with bronchial biopsies. Clinical data and tissues from 10 age-matched mild-asthmatic and 10 healthy nonallergic subjects were used for comparison.

RESULTS

Swimmers had increased airway mucosa eosinophil and mast cell counts than did controls (P < .05). They had more goblet cell hyperplasia and higher mucin expression than did healthy or asthmatic subjects (P < .05). A greater submucosal type I and III collagen expression and tenascin deposition was also observed in swimmers than in controls (P < .05). Neither exhaled nitric oxide nor airway responsiveness to methacholine or eucapnic voluntary hyperpnea challenge correlated with these inflammatory and remodeling changes.

CONCLUSION

Intense, long-term swimming training in indoor chlorinated swimming pools is associated with airway changes similar to those seen in mild asthma, but with higher mucin expression. These changes were independent from airway hyperresponsiveness. The long-term physiological and clinical consequences of these changes remain to be clarified.

Application of the BRAFO tiered approach for benefit-risk assessment to case studies on dietary interventions

The respective examples, described in this paper, illustrate how the BRAFO-tiered approach, on benefit-risk assessment, can be tested on a wide range of case studies. Various results were provided, ranging from a quick stop as the result of non-genuine benefit-risk questions to continuation through the tiers into deterministic/probabilistic calculations. The paper illustrates the assessment of benefits and risks associated with dietary interventions. The BRAFO tiered approach is tested with five case studies. In each instance, the benefit-risk approach is tested on the basis of existing evaluations for the individual effects done by others; no new risk or benefit evaluations were made. The following case studies were thoroughly analysed: an example of food fortification, folic acid fortification of flour, macronutrient replacement/food substitution; the isocaloric replacement of saturated fatty acids with carbohydrates; the replacement of saturated fatty acids with monounsaturated fatty acids; the replacement of sugar-sweetened beverages containing mono- and disaccharides with low calorie sweeteners and an example of addition of specific ingredients to food: chlorination of drinking water.

[Physiological and psychophysiological indices dynamics in operators with three-shift working day in different working conditions]

It was shown that intense operator work in pulp and paper industry (bleachers and chlorinators) with changes in shift time (day, evening, night) causes fatigue. The fatigue in operators was indicated by increasing number of errors in sensomotor coordination test and coordination index, and among chlorinators it was accompanied by deterioration of state of health. Manifestations of 24 hours' rhythm of physiological functions were detected by changes in body temperature (among bleachers), heart rate, blood pressure and sensomotor coordination indices (all operators). Harmful chemical substances (chlorine and chlorine dioxide) in the air negatively influence psychophysiological status among clorinators.

Airway response to chlorine inhalation (bleach) among cleaning workers with and without bronchial hyperresponsiveness

BACKGROUND

Symptoms of obstructive lung disease in domestic cleaning staff have been related to the use of bleach and other irritant cleaning products.

MATERIAL AND METHODS

Included in the study were thirteen cleaning employees with work-related asthma-like symptoms, three asthmatic controls and three atopic subjects without bronchial hyperresponsiveness (BHR) who had no exposure to cleaning products. The study protocol consisted of a methacholine test, sputum induction and fraction of exhaled nitric oxide measurement (FENO) both at baseline and 24 hr after a 1-hr inhalation challenge with either placebo or bleach at a concentration of 0.4 ppm of chlorine.

RESULTS

The inhalation of the placebo caused no bronchial reactions. Mean maximum fall in FEV(1) during challenge testing with bleach was significantly higher than the values obtained during the placebo challenge. Inhalation challenge with bleach elicited two isolated late asthmatic reactions and one dual asthmatic reaction. Of all the patients who underwent challenge testing with bleach, only one had a ≥2-fold decrease in methacholine PC(20) 24 hr after the challenge. No significant correlation was found between maximum fall in FEV(1) and PC(20) methacholine. Following challenge testing with bleach, no clinically significant changes in sputum cell counts or FENO were detected.

CONCLUSIONS

These results suggest that bleach inhalation at a concentration of 0.4 ppm-a concentration below 8-hr permissible occupational exposure level-brings about a substantial decrease in FEV1 in subjects with and without BHR. Some subjects have a positive challenge response to bleach inhalation.

Swimming pool-induced asthma

A 13-year-old elite swimmer presented with wheezing after indoor swimming training. On the basis of her clinical history and the tests performed, exercise-induced asthma and mold-induced asthma were ruled out and a diagnosis of chlorine-induced asthma was made.

Effects of chlorine and exercise on the unified airway in adolescent elite Scottish swimmers

BACKGROUND

Chlorine metabolites and high training load may produce exercise-induced bronchospasm (EIB) in elite swimmers. The aim of this study was to assess the combined effects of chlorine and exercise on the unified airway of adolescent elite swimmers.

METHODS

The Scottish Midlands District squad were assessed during an indoor pool session at the National Swimming Academy. Athletes trained at least 8 h per week. Subjects underwent tidal (T(NO)) and nasal (N(NO)) exhaled NO and peak nasal inspiratory flow (PNIF) pre and post a 2 h session. A physiological exercise challenge assessed EIB in n = 36 swimmers (>10% fall in forced expiratory volume in 1 s (FEV(1))).

RESULTS

Combined and free chlorine levels (mg/l) were 1.66 and 0.3 respectively. n = 36 swimmers (mean age 13.3 years) were assessed: n = 8 (22%) had known asthma; n = 13 (36%) had a positive physiological challenge; 18 (50%) complained of symptoms suggestive of EIB. n = 10/28 (36%) who did not have asthma were found to have a positive exercise challenge. There was no significant association between reported exercise symptoms and positive exercise test. There was no significant change in T(NO) or N(NO) for pre vs postexposure, irrespective of asthma diagnosis or AHR. n = 15 (42%) swimmers complained of worsening nasal symptoms postexposure, but only n = 7 (14%) had a demonstrable fall in PNIF (mean 33 l/min). No significant association was found between PNIF and symptoms.

CONCLUSIONS

Combined exposure to chlorine and exercise did not affect surrogate markers of inflammation in the unified airway. There was a high prevalence of undiagnosed EIB.

[Genotoxicity of drinking water during chlorine and chloramine disinfection and the influence of disinfection conditions using the umu-test]

In this study, the effects of disinfectant dosage, reaction time and the ratio of Cl2 to N of disinfectant on genotoxicity of effluent of ozone-biological activated carbon (O3-BAC) during chlorine or chloramine disinfection were investigated using umu-test. It was found that, the genotoxicity of effluent of O3-BAC before disinfection ranged from 20-70 ng/L, and it increased after disinfection by chlorine or chloramines. With the same reaction time(24 h), genotoxicity after chlorination (40-95 ng/L) was higher than that after chloramination (20-40 ng/L) under same initial dosage. For chlorination, with initial dosage increasing from 0 mg/L to 10 mg/L, genotoxicity increased firstly, and got the maximum value at about 0.5-1 mg/L dosage, then decreased and got the minimum value at about 3-5 mg/L dosage, and finally increased again. For chloramination, genotoxicity didn't change that much. With the dosage of 3 mg/L and reaction time increasing from 0 h to 72 h, no matter for chlorine or chloramines disinfection, genotoxicity of effluent of O3-BAC both increased firstly, and got the maximum value at about 2 h, then decreased and got the minimum value at about 18 h, and finally increased again, and genotoxicity after chlorine disinfection (83-120 ng/L) was higher than that after chloramines disinfection (20-62 ng/L) under same reaction time. Further more, effects of the different ratios of Cl2 to N of disinfectant on genotoxicity of effluent of O3-BAC were also studied. Results of this study demonstrate that under test conditions, chloramine disinfection is safer than chlorine disinfection in the aspect of genotoxicity for drinking water, and the changes of genotoxicity are different from those of total HAAs.

Estimation of chlorination by-products presence in drinking water in epidemiological studies on adverse reproductive outcomes: a review

Chlorination of drinking water is essential to prevent waterborne disease. However, chlorine reacts with organic matter present in surface waters to form various by-products. In the last decade, several epidemiological studies have been conducted to determine the connection between exposure to these chlorination by-products (CBPs) and human health defects, such as adverse reproductive outcomes. However, the methodology used to assess exposure of pregnant women in these studies had serious limitations, particularly in relation to determining CBP presence in the subject's tap water. The purpose of this paper is to critically review of methods used to evaluate the CBP presence in a subject's tap water for exposure assessment purposes in epidemiological studies focused on adverse reproductive outcomes and CBPs in drinking water. Interest is directed more precisely at space-time features related to CBPs for an optimal estimation of their presence in a subject's tap water.

[Disinfection by-products reduction of combined disinfection by chlorine and monochloramines in distribution system]

Halogen disinfection by-products of four chlorined disinfection processes with long contact time in distribution system was compared in the work. These four disinfection processes are free chlorine, monochloramines, free chlorine disinfection in clearwelles while chloramines in distribution system, sequential chlorination disinfection with short-term free chlorine plus chloramines. According to the research, free chlorine generates most trihalomethanes (THMs) and haloacetic acids (HAAs) both in clearwells and distribution system, while monochloramines barely yield halogen DBPs. Free chlorine disinfection in clearwelles while chloramines in distribution system could reduce 9.6% of THMs and 42% of HAAs in 24 h contact time of distribution system compared with free chlorine. But free chlorine has contacted with water for 2 h in this process, halogen DBPs have been yielded substantially. Process of sequential chlorination disinfection could control DBPs more effectively due to keeping a short contact time of free chlorine and water. 48% of THMs and 72% of HAAs are reduced in 24h compared with free chlorine. In conclusion, sequential chlorination disinfection is a more effective disinfection process for controlling DBPs and water safety.

Health impacts of long-term exposure to disinfection by-products in drinking water in Europe: HIWATE

There appears to be very good epidemiological evidence for a relationship between chlorination by-products, as measured by trihalomethanes (THMs), in drinking water and bladder cancer, but the evidence for other cancers, including colorectal cancer appears to be inconclusive and inconsistent. There appears to be some evidence for a relationship between chlorination by-products, as measured by THMs, and small for gestational age (SGA)/intrauterine growth retardation (IUGR) and preterm delivery, but evidence for other outcomes such as low birth weight (LBW), stillbirth, congenital anomalies and semen quality appears to be inconclusive and inconsistent.The overall aim of the HIWATE study is to investigate potential human health risks (e.g. bladder and colorectal cancer, premature births, SGA, semen quality, stillbirth, congenital anomalies) associated with long-term exposure to low levels of disinfectants (such as chlorine) and DBPs occurring in water for human consumption and use in the food industry. The study will comprise risk-benefit analyses including quantitative assessments of risk associated with microbial contamination of drinking water versus chemical risk and will compare alternative treatment options. The outcome will be improved risk assessment and better information for risk management. The work is divided into different topics (exposure assessment, epidemiology, risk assessment and management) and studies.

Association between swimming pool operator certification and reduced pool chemistry violations--Nebraska, 2005-2006

Previous studies have recommended mandatory education for all public pool operators, but substantiating data are limited. This study evaluates associations between pool operator certification and chemistry violations by using 2005-2006 Nebraska routine pool inspection reports. Training and certification for nonmunicipal pool operators are only required in two Nebraska counties. Free chlorine violations for nonmunicipal pool inspections were compared in counties with and without certified operator requirements. To control for water supply pH, inspections from nonmunicipal pools with shared-source water in two counties (one requiring certification) were compared for concurrent pH and free chlorine violations. Compared with locations that require certified operators, free chlorine violations and concurrent pH and free chlorine violations were twice as likely in locations without certification. As a result, pools without required operator certification might pose greater health risks. These results demonstrate the benefit of requiring pool operator certification to help prevent recreational water illnesses.

Reactive Airways Dysfunction Syndrome in Housewives Due to a Bleach–Hydrochloric Acid Mixture

The sudden onset of asthmalike symptoms and persistence of airway reactivity following an acute exposure to an irritant gas or vapor has been termed reactive airways dysfunction syndrome (RADS). A mixture of sodium hypochlorite (bleach, 40%) and hydrochloric acid (18%) is commonly used as a household cleaning solution in our region. From this mixture, chlorine gas is produced, which can cause airway damage and ensuing RADS. Here we describe findings of patients with RADS due to this cleaning mixture, and determine factors associated with a favorable outcome. Data were collected retrospectively on 55 symptomatic patients presenting to our emergency department after inhalation exposure to a mixture of bleach and hydrochloric acid. Symptoms, past medical and smoking history, details of the exposure, initial peak expiratory flow rate (PEFR) and oxygenation, and acute reversibility of airways obstruction were documented. All patients met previously defined criteria for the diagnosis of RADS, but did not undergo methacholine challenge testing and bronchoalveolar lavage or histopathologic study. Fifty patients were followed over the course of 3 mo. The majority of exposures (64%) occurred in the bathroom or kitchen. Only 21 of 55 (38%) patients showed an improvement in PEFR of 15% or greater following two beta(2)-agonist inhalation treatments. In follow-up, 48 patients (87%) improved clinically and functionally (FEV(1)). Seven patients (13%) deteriorated, with ARDS developing in two, one of whom died from respiratory failure. Advanced age, initial low PEFR, exposure in a small enclosed area, use immediately after mixing, and prolonged short- and long-term exposures were associated with a poorer prognosis. This descriptive study is the largest case series in the literature of RADS developing after exposure to a bleach-hydrochloric acid mixture. The optimum acute treatment and long-term outcomes for patients with RADS due to this combination still need to be determined.

Water disinfection by-products and pre-labor rupture of membranes

The causes of term pre labor rupture of membranes (term PROM) remain poorly defined. The authors conducted a record-based prevalence study to explore a possible relation between disinfection by-products in drinking water and term PROM in an Australian community with spatially variable trihalomethane and nitrate levels. A multilevel statistical model was used to examine the relation between factors operating at the levels of the individual, district, and water distribution zone and the prevalence of PROM at term among 16,229 women in Perth, Western Australia (2002-2004). Adjusted odds ratios for term PROM increased with increasing tertiles of nitrate exposure (moderate exposure: odds ratio = 1.23, 95% confidence interval: 1.03, 1.52; high exposure: odds ratio = 1.47, 95% confidence interval: 1.20, 1.79), but there was no significant relation with exposure to trihalomethanes. This study raises the possibility that water contaminants may promote the development of PROM at term.

Human health risk assessment of chlorinated disinfection by-products in drinking water using a probabilistic approach

The presence of chlorinated disinfection by-products (DBPs) in drinking water is a public health issue, due to their possible adverse health effects on humans. To gauge the risk of chlorinated DBPs on human health, a risk assessment of chloroform (trichloromethane (TCM)), bromodichloromethane (BDCM), dibromochloromethane (DBCM), bromoform (tribromomethane (TBM)), dichloroacetic acid (DCAA) and trichloroacetic acid (TCAA) in drinking water was carried out using probabilistic techniques. Literature data on exposure concentrations from more than 15 different countries and adverse health effects on test animals as well as human epidemiological studies were used. The risk assessment showed no overlap between the highest human exposure dose (EXP(D)) and the lowest human equivalent dose (HED) from animal test data, for TCM, BDCM, DBCM, TBM, DCAA and TCAA. All the HED values were approximately 10(4)-10(5) times higher than the 95th percentiles of EXP(D). However, from the human epidemiology data, there was a positive overlap between the highest EXP(D) and the lifetime average daily doses (LADD(H)) for TCM, BDCM, DCAA and TCAA. This suggests that there are possible adverse health risks such as a small increased incidence of cancers in males and developmental effects on infants. However, the epidemiological data comprised several risk factors and exposure classification levels which may affect the overall results.

Rapid and severe tooth erosion from swimming in an improperly chlorinated pool: case report

This case report describes the almost complete loss of enamel by acid erosion, particularly from the anterior teeth, in a woman who swam daily for 2 weeks in an improperly chlorinated swimming pool in Cuba. It emphasizes the need for both swimmers and swimming pool staff to ensure that the water has been properly chlorinated and that the pH has been adjusted to 7.5.

Chlorinated drinking water, cancers and adverse health outcomes in Gangtok, Sikkim, India

Long-term impacts of drinking chlorinated water on the incidence of cancers and other adverse health outcomes were assessed in a population-based cross-sectional study. The study was conducted by comparing a group exposed to chlorinated drinking water for more than thirty years with control groups with less or no exposure to chlorine. A house-to-house survey was completed to gather information on residential history, age, education, income, source and extent of treatment of water and health characteristics. All residents below thirty years of age were excluded from the database used for analyses to ensure that the groups were comparable. Fourteen cancer cases were found in the long-term exposed groups of 1085 persons and 9 cancer cases in the two control populations of 725 persons. The odds ratio for cancers (OR) was 1.05 (95% CI = 0.43-2.65) and is not statistically significant. Reciprocal or inverse odds [corrected] ratios for gastrointestinal disorders, kidney problems and skin infections were statistically significant ranging from 2.06 (95% CI = 1.01-4.17) to 2.2 (95% CI = 1.45-3.33). These OR values indicate that there is no significant association between the incidence of cancer and exposure to chlorinated water while chlorinating drinking water significantly reduced the incidence of non-carcinogenic adverse health effects like gastrointestinal diseases, skin infections, and kidney diseases.

Exhaled nitric oxide in children after accidental exposure to chlorine gas

Chronic exposure to chlorine gas has been shown to cause occupational asthma. Acute inhalation of chlorine is known to cause airway inflammation and induce airway nitric oxide formation. Exhaled nitric oxide may therefore be a marker of airway damage after chlorine gas exposure. After accidental chlorine gas exposure in a swimming pool, exhaled nitric oxide and pulmonary function were repeatedly measured in 18 children over a 1-mo period. Symptomatic children with impaired pulmonary function had higher nitric oxide levels on the day after the exposure compared to day 8 and day 28. Differences in exhaled nitric oxide were more pronounced at a higher exhalation flow compared to lower flow, suggesting peripheral rather than central airway damage. This was in accordance with the observed changes in pulmonary function. No changes in exhaled nitric oxide were seen in asymptomatic children. These data suggest that acute chlorine gas exposure results in a mild increase of exhaled nitric oxide in symptomatic children.

Chlorine and its impact on an emergency department

INTRODUCTION

An incident involving the release of chlorine gas from the pump room at a local swimming pool resulted in 54 patients seeking treatment in the emergency departments (EDs) of two local, tertiary-level hospitals in Singapore. The hospital hazardous materials (HAZMAT) disaster plan was activated. This report describes how one of the EDs organized in response to the disaster.

EVENT

Of the 54 people seeking treatment, 36 were treated in the ED at the Singapore General Hospital. The patients were decontaminated at shower facilities prior to entering the ED. The ED was reorganized to cope with existing patients, as well as the large influx of patients from the event site. A protocol was established in coordination with the local drug and poison information center to manage the patients who suffered from chlorine inhalation. Most patients were observed in the ED and subsequently discharged. Outpatient review appointments were scheduled.

INJURIES

Acute respiratory symptoms were the most common symptoms., Four children and four adults were admitted to the hospital, and the other patients were discharged from the ED after observation. All of the chest x-rays were normal on the day of the chlorine inhalation. There were no mortalities or significant morbidities, even up to six months after the incident.

CONCLUSIONS

Although this chlorine HAZMAT incident did not cause severe injuries, and only a limited number of persons required admission to the hospital, some valuable lessons were learned.

[Evaluation of the occurrence of a rare work related disease in a cohort of workers employed in the processing of paper]

The aim of our study is evaluating occupational exposure in a factory named "Poligrafico Zecca dello Stato" in Foggia. The workers had a occupational disease "chlorine related parodontal disease" indemnified by INAIL (Italian Occupational Assurance). The study demonstrated the workers have been indemnified worked as engineer, drying and electrolysis process employed. The study showed that the workers indemnified without legal action were different in respect of workers that take legal action, because the last showed, paradoxically, a chlorine occupational exposure. The explanation of this paradox might be the production cycle non acknowledge by operators.

Infant swimming practice, pulmonary epithelium integrity, and the risk of allergic and respiratory diseases later in childhood

OBJECTIVE

Irritant gases and aerosols contaminating the air of indoor swimming pools can affect the lung epithelium and increase asthma risk in children. We evaluated the impact of infant swimming practice on allergic status and respiratory health later in childhood.

METHODS

Clara cell protein, surfactant-associated protein D, and total and aeroallergen-specific immunoglobulin E were measured in the serum of 341 schoolchildren aged 10 to 13 years, among whom 43 had followed an infant swimming program. Asthma was defined as doctor-diagnosed asthma and/or positive exercise-induced bronchoconstriction (15% decrease in postexercise forced expiratory volume).

RESULTS

There were no significant differences between the infant swimming group and the other children regarding the levels of exhaled nitric oxide and total or aeroallergen-specific serum immunoglobulin E. Children who swam as infants showed, by contrast, a significant decrease of serum Clara cell protein and of the serum Clara cell protein/surfactant-associated protein D ratio integrating Clara cell damage and permeability changes of the lung epithelial barrier. These effects were associated with higher risks of asthma and of recurrent bronchitis. Passive exposure to tobacco alone had no effect on these outcomes but seemed to interact with infant swimming practice to increase the risk of asthma or of recurrent bronchitis.

CONCLUSIONS

Our data suggest that infant swimming practice in chlorinated indoor swimming pools is associated with airways changes that, along with other factors, seem to predispose children to the development of asthma and recurrent bronchitis.

Chlorination byproducts, their toxicodynamics and removal from drinking water

No doubt that chlorination has been successfully used for the control of water borne infections diseases for more than a century. However identification of chlorination byproducts (CBPs) and incidences of potential health hazards created a major issue on the balancing of the toxicodynamics of the chemical species and risk from pathogenic microbes in the supply of drinking water. There have been epidemiological evidences of close relationship between its exposure and adverse outcomes particularly the cancers of vital organs in human beings. Halogenated trihalomethanes (THMs) and haloacetic acids (HAAs) are two major classes of disinfection byproducts (DBPs) commonly found in waters disinfected with chlorine. The total concentration of trihalomethanes and the formation of individual THM species in chlorinated water strongly depend on the composition of the raw water, on operational parameters and on the occurrence of residual chlorine in the distribution system. Attempts have been made to develop predictive models to establish the production and kinetics of THM formations. These models may be useful for operational purposes during water treatment and water quality management. It is also suggested to explore some biomarkers for determination of DBP production. Various methods have been suggested which include adsorption on activated carbons, coagulation with polymer, alum, lime or iron, sulfates, ion exchange and membrane process for the removal of DBPs. Thus in order to reduce the public health risk from these toxic compounds regulation must be inforced for the implementation of guideline values to lower the allowable concentrations or exposure.

Chlorine emission during the chlorination of water--case study

This paper deals with the incident of the excessive use of chlorine and leakage of unused chlorine from an industrial chlorination cistern and the lesson learned.

The effect of nebulized NaHCO3 treatment on "RADS" due to chlorine gas inhalation

Chlorine is one of the most common substances involved in toxic inhalation. As with all irritant gases, the airway injuries caused by chlorine gas may result in clinical manifestations similar to those of asthma. In this study, we investigated the effect of nebulized sodium bicarbonate (NSB) on the treatment and quality of life (QoL) of victims exposed to chlorine gas. Forty-four consecutive patients with reactive airways dysfunction syndrome (RADS) due to chlorine inhalation (40 females and 4 males, age range 17-56 yr) were included in this study. Patients were placed in control and treatment groups in a sequential odd-even fashion based on their order of presentation. Treatment of all patients included corticosteroids and nebulized short-acting beta2-agonists. Then the control group (n = 22) received nebulized placebo (NP), and the NSB group (n = 22) received NSB treatment (4 cm3 of 4.20% sodium bicarbonate solution). A quality of life (QoL) questionnaire and pulmonary function tests (PFTs) were performed before and after treatments in both groups. The most common symptoms were dyspnea (82%) and chest tightness (82%). Baseline characteristics of both groups were similar. Compared to the placebo group, the NSB group had significantly higher FEV1 values at 120 and 240 min (p < .05). Significantly more improvement in QoL questionnaire scores occurred in the NSB group compared to the NP group (p < .001). Thus, NSB is a clinically useful treatment, as tested by PFTs and QoL questionnaire, for patients with RADS caused by exposure to chlorine gas.

Chlorination disinfection by-products in drinking water and the risk of adult leukemia in Canada

The authors conducted a population-based case-control study of 1,068 incident leukemia cases and 5,039 controls aged 20-74 years during 1994-1997 to examine the association between exposure to drinking water chlorination disinfection by-products and adult leukemia risk in Canada. Residence and drinking water source histories and data from municipal water supplies were used to estimate individual chlorination disinfection by-product exposure according to water source, chlorination status, and chlorination disinfection by-product levels during the 40-year period before the interview. The analysis included 686 cases and 3,420 controls for whom water quality information was available for at least 30 of these years. Increased risk of chronic myeloid leukemia was associated with increasing years of exposure to different chlorination disinfection by-product indexes, with an adjusted odds ratio of 1.72 (95% confidence interval: 1.01, 3.08) for the highest exposure duration to total trihalomethanes of more than 40 microg/liter. In contrast, the risk of the other studied leukemia subtypes was found to decrease with increasing years of exposure to chlorination disinfection by-products. A protective effect was noted for chronic lymphoid leukemia (odds ratio = 0.60, 95 percent confidence interval: 0.41, 0.87) associated with the highest exposure duration to total trihalomethanes of more than 40 microg/liter. More studies with long-term exposure measures and large enough to evaluate leukemia subtypes are needed to further understanding of the issue.

Progressive vocal cord dysfunction subsequent to a chlorine gas exposure

Chlorine gas inhalation, similar to other toxic gas exposures, can impart a variety of effects to the entire airway ranging from mucous membrane irritation to acute respiratory distress syndrome. The extent and location of damage is determined by numerous situational factors such as the duration of exposure, quantity of gas released, environmental factors, and instituted chemical defense measures. Reactive airways dysfunction and nonspecific bronchial hyperresponsiveness are commonly reported as sequelae to chlorine exposure. This article constitutes the first case of a single antecedent chlorine exposure inducing progressive vocal cord dysfunction.