Asthma, chronic bronchitis, and exposure to irritant agents in occupational domestic cleaning: a nested case-control study

Indoor cooking and cleaning as a source of outdoor air pollution in urban environments

Indoor sources of air pollution, such as from cooking and cleaning, play a key role in indoor gas-phase chemistry. The focus of the impact of these activities on air quality tends to be indoors, with less attention given to the impact on air quality outside buildings. This study uses the INdoor CHEmical Model in Python (INCHEM-Py) and the Advanced Dispersion Modelling System (ADMS) to quantify the impact cooking and cleaning have on indoor and outdoor air quality for an idealised street of houses. INCHEM-Py has been developed to determine the concentrations of 106 indoor volatile organic compounds at the point they leave a building (defined as near-field concentrations). For a simulated 140 m long street with 10 equi-distant houses undertaking cooking and cleaning activities, the maximum downwind concentration of acetaldehyde increases from a background value of 0.1 ppb to 0.9 ppb post-cooking, whilst the maximum downwind chloroform concentrations increase from 1.2 to 6.2 ppt after cleaning. Although emissions to outdoors are higher when cooking and cleaning happen indoors, the contribution of these activities to total UK emissions of volatile organic compounds is low (less than 1%), and comprise about a quarter of those emitted from traffic across the UK. It is important to quantify these emissions, particularly as continued vehicle technology improvements lead to lower direct emissions outdoors, making indoor emissions relatively more important. Understanding how indoor pollution can affect outdoor environments, will allow better mitigation measures to be designed in the future that can take into account all sources of pollution that contribute to human exposure.

Airway Diseases Related to the Use of Cleaning Agents in Occupational Settings

Exposure to disinfectants and cleaning products (DCPs) is now a well-established risk factor for work-related asthma (WRA). However, questions remain on the specific causal agents and pathophysiological mechanisms. Few studies have also reported an association between DCPs and rhinitis or chronic obstructive pulmonary disease. This review discusses the recent evidence pertaining to airway diseases attributable to occupational exposure to DCPs. In contrast to other agents, the incidence of WRA due to DCPs has increased over time. The use of DCPs in spray form has clearly been identified as an added risk factor. The mechanisms for WRA associated with DCPs remain poorly studied; however, both allergic and nonallergic responses have been described, with irritant mechanisms thought to play a major role. An early diagnostic workup based on clinical assessment accompanied by evaluation of lung function and immunological and airway inflammatory markers is important to guide optimal care and exposure avoidance to the implicated agent. Future research should focus on the effects of "green" products, pathophysiological mechanisms, and quantitative exposure assessment including the use of barcode-based methods to identify specific agents. There is an urgent need to strengthen preventive measures and interventions to reduce the burden of airway diseases associated with DCPs.

Household laundry detergents disrupt barrier integrity and induce inflammation in mouse and human skin

BACKGROUND

Epithelial barrier impairment is associated with many skin and mucosal inflammatory disorders. Laundry detergents have been demonstrated to affect epithelial barrier function in vitro using air-liquid interface cultures of human epithelial cells.

METHODS

Back skin of C57BL/6 mice was treated with two household laundry detergents at several dilutions. Barrier function was assessed by electric impedance spectroscopy (EIS) and transepidermal water loss (TEWL) measurements after the 4 h of treatments with detergents. RNA sequencing (RNA-seq) and targeted multiplex proteomics analyses in skin biopsy samples were performed. The 6-h treatment effect of laundry detergent and sodium dodecyl sulfate (SDS) was investigated on ex vivo human skin.

RESULTS

Detergent-treated skin showed a significant EIS reduction and TEWL increase compared to untreated skin, with a relatively higher sensitivity and dose-response in EIS. The RNA-seq showed the reduction of the expression of several genes essential for skin barrier integrity, such as tight junctions and adherens junction proteins. In contrast, keratinization, lipid metabolic processes, and epidermal cell differentiation were upregulated. Proteomics analysis showed that the detergents treatment generally downregulated cell adhesion-related proteins, such as epithelial cell adhesion molecule and contactin-1, and upregulated proinflammatory proteins, such as interleukin 6 and interleukin 1 beta. Both detergent and SDS led to a significant decrease in EIS values in the ex vivo human skin model.

CONCLUSION

The present study demonstrated that laundry detergents and its main component, SDS impaired the epidermal barrier in vivo and ex vivo human skin. Daily detergent exposure may cause skin barrier disruption and may contribute to the development of atopic diseases.

Cleaning Tasks and Products and Asthma Among Health Care Professionals

OBJECTIVE

Health care workers are at risk for work-related asthma, which may be affected by changes in cleaning practices. We examined associations of cleaning tasks and products with work-related asthma in health care workers in 2016, comparing them with prior results from 2003.

METHODS

We estimated asthma prevalence by professional group and explored associations of self-reported asthma with job-exposure matrix-based cleaning tasks/products in a representative Texas sample of 9914 physicians, nurses, respiratory/occupational therapists, and nurse aides.

RESULTS

Response rate was 34.8% (n = 2421). The weighted prevalence rates of physician-diagnosed (15.3%), work-exacerbated (4.1%), and new-onset asthma (6.7%) and bronchial hyperresponsiveness symptoms (31.1%) were similar to 2003. New-onset asthma was associated with building surface cleaning (odds ratio [OR], 1.91; 95% confidence interval [CI], 1.10-3.33), use of ortho-phthalaldehyde (OR, 1.77; 95% CI, 1.15-2.72), bleach/quaternary compounds (OR, 1.91; 95% CI, 1.10-3.33), and sprays (OR, 1.97; 95% CI, 1.12-3.47).

CONCLUSION

Prevalence of asthma/bronchial hyperresponsiveness seems unchanged, whereas associations of new-onset asthma with exposures to surface cleaning remained, and decreased for instrument cleaning.

The epithelial barrier: The gateway to allergic, autoimmune, and metabolic diseases and chronic neuropsychiatric conditions

Since the 1960 s, our health has been compromised by exposure to over 350,000 newly introduced toxic substances, contributing to the current pandemic in allergic, autoimmune and metabolic diseases. The "Epithelial Barrier Theory" postulates that these diseases are exacerbated by persistent periepithelial inflammation (epithelitis) triggered by exposure to a wide range of epithelial barrier-damaging substances as well as genetic susceptibility. The epithelial barrier serves as the body's primary physical, chemical, and immunological barrier against external stimuli. A leaky epithelial barrier facilitates the translocation of the microbiome from the surface of the afflicted tissues to interepithelial and even deeper subepithelial locations. In turn, opportunistic bacterial colonization, microbiota dysbiosis, local inflammation and impaired tissue regeneration and remodelling follow. Migration of inflammatory cells to susceptible tissues contributes to damage and inflammation, initiating and aggravating many chronic inflammatory diseases. The objective of this review is to highlight and evaluate recent studies on epithelial physiology and its role in the pathogenesis of chronic diseases in light of the epithelial barrier theory.

Effect of altered human exposome on the skin and mucosal epithelial barrier integrity

Pollution in the world and exposure of humans and nature to toxic substances is continuously worsening at a rapid pace. In the last 60 years, human and domestic animal health has been challenged by continuous exposure to toxic substances and pollutants because of uncontrolled growth, modernization, and industrialization. More than 350,000 new chemicals have been introduced to our lives, mostly without any reasonable control of their health effects and toxicity. A plethora of studies show exposure to these harmful substances during this period with their implications on the skin and mucosal epithelial barrier and increasing prevalence of allergic and autoimmune diseases in the context of the "epithelial barrier hypothesis". Exposure to these substances causes an epithelial injury with peri-epithelial inflammation, microbial dysbiosis and bacterial translocation to sub-epithelial areas, and immune response to dysbiotic bacteria. Here, we provide scientific evidence on the altered human exposome and its impact on epithelial barriers.

Effects of disinfection by-products in swimming pool environments on the immunological mechanisms of respiratory diseases

Swimming in pools is a popular and healthy recreational activity. However, potential adverse health effects from disinfection byproduct (DBP) exposure in pool water are concerning. This study evaluated how such DBP exposure affects the respiratory system. DBP exposure was simulated with an animal-specific pool environment model. Experimental animals were exposed to DBPs for a specified duration and frequency over 4 weeks. The wet and dry weights of murine lungs were measured, with no significant differences observed. There were no significant differences in interkeukin (IL)-2/4/10, and interferon-γ levels. However, IL-6 expression decreased in the experimental group. To investigate the effects of DBP exposure on immune cell response, various samples, such as bronchoalveolar lavage fluid, lymph nodes, spleen, and thymus, were collected for T-cell isolation and fluorescence-activated cell sorting. Asthma-related blood cell distribution was analyzed using a complete blood count test; no significant differences were found. Thus, DBP exposure through this model did not induce substantial lung tissue damage, major alterations in cytokine expression (besides IL-6), significant immune cell responses, or changes in asthma-associated blood cell distribution. However, considering earlier results, future studies should focus on specific types, intensity, and duration of exercise that could affect DBP exposure-related immune-inflammatory responses.

Evaluation of the impact of different disinfectants on new coronavirus and human health

A new health threat was appeared in 2019 known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) or coronavirus disease 2019 (COVID-19). The new coronavirus distributed all over the world and caused millions of deaths. One way to incomplete the process of COVID-19 transfer from one person to another is using disinfectants. A narrative review study was done on manuscript published documents about the stability of the virus, different types of disinfectants and the effects of disinfectants on SARS-CoV2 and environment from 2005 to 2022 based on Searched databases included Google Scholar, Springer, PubMed, Web of Science and Science Direct (Scopus). All relevant studies published 2005 until 2022 gathered. According to the databases, 670 articles were retrieved. Thirty studies were screened after review and 30 full-text articles entered into the analysis process. Finally, 14 articles were selected in this study. New coronavirus could survive until 9 days in room temperature; the surviving time decreases if temperature increases. The virus can survive in various plastic, glass, and metal surfaces for hours to days. Disinfectants, such as alcohol, isopropanol, formaldehyde, glutaraldehyde, and ethanol, can kill 70-90% viruses in up to 30 s but should be noted that these disinfectants are recognized by Occupational Safety and Health Administration (OSHA) as a potential carcinogen. According to the different reports, increased duration and level of disinfectant exposure can have negative impacts on human and animal health including upper and lower respiratory tract irritation, inflammation, edema, ulceration, and allergic reactions.

Chemical Pneumonitis and Reactive Airways Dysfunction Syndrome After Fumigation Exposure to Dimethanol and Glutaraldehyde: A Silent Menace Unmasked

Chemical pneumonitis caused by dimethanol and glutaraldehyde exposure is a serious medical condition that requires prompt and effective treatment. As per a literature search in Google Scholar, PubMed, and Scopus, this is the first instance of chemical pneumonitis caused after fumigation with dimethanol and glutaraldehyde inhalation. This article discusses the factors that can contribute to the development of chemical pneumonitis and outlines the diagnostic and treatment options available to healthcare professionals. By understanding the causes and consequences of dimethanol- and glutaraldehyde-induced chemical pneumonitis, medical professionals can provide better care to their patients and help prevent future cases of this potentially life-threatening condition. This describes a case of a 60-year-old female who presented to the emergency department complaining of acute onset of shortness of breath approximately 48 hours after being exposed to dimethanol and glutaraldehyde while working in intensive care. After 13 days, the patient's symptoms subsided and she was discharged. On follow-up, after 1 month, there was a marked resolution of the initial symptoms.

Allergies Come Clean: The Role of Detergents in Epithelial Barrier Dysfunction

PURPOSE OF REVIEW

The prevalence and incidence of allergic disease have been rising in Westernized countries since the twentieth century. Increasingly, evidence suggests that damage to the epithelium initiates and shapes innate and adaptive immune responses to external antigens. The objective of this review is to examine the role of detergents as a potential risk factor for developing allergic disease.

RECENT FINDINGS

Herein, we identify key sources of human detergent exposure. We summarize the evidence suggesting a possible role for detergents and related chemicals in initiating epithelial barrier dysfunction and allergic inflammation. We primarily focus on experimental models of atopic dermatitis, asthma, and eosinophilic esophagitis, which show compelling associations between allergic disease and detergent exposure. Mechanistic studies suggest that detergents disrupt epithelial barrier integrity through their effects on tight junction or adhesion molecules and promote inflammation through epithelial alarmin release. Environmental exposures that disrupt or damage the epithelium may account for the increasing rates of allergic disease in genetically susceptible individuals. Detergents and related chemical compounds represent possible modifiable risk factors for the development or exacerbation of atopy.

Eye and airway symptoms in hospital staff exposed to a product containing hydrogen peroxide, peracetic acid, and acetic acid

BACKGROUND

Sporicidal products containing hydrogen peroxide (HP), peracetic acid (PAA), and acetic acid (AA) are used widely in multiple industries, including healthcare. Despite widespread use in healthcare, few studies have assessed associations between exposures to HP, PAA, and AA, and work-related symptoms in these settings.

METHODS

In 2018, we performed a health and exposure assessment at a hospital where a sporicidal product consisting of HP, PAA, and AA, was used as the primary cleaner on hospital surfaces. We collected 56 personal and mobile air samples for HP, PAA, and AA on participants while they performed their regular cleaning duties; collected area samples for HP (n = 28), PAA (n = 28), and AA (n = 70) in multiple hospital locations where cleaning was performed; and administered a postshift survey to assess eye, skin, and upper and lower airway symptoms that occurred cross-shift or in the previous 4 weeks.

RESULTS

Full-shift exposure levels for HP (range: <3-559 ppb), PAA (range: <0.2-8 ppb), and AA (range: <5-915 ppb) were all below US occupational exposure limits. We observed positive associations (p < 0.05) between shift, departmental average, and departmental 95th percentile exposures to HP, PAA, and AA vapors, and work-related acute (cross-shift) and chronic (previous 4 weeks) eye, upper airway, and lower airway symptoms after adjusting for age, gender, smoking status, use of other cleaning products containing sensitizers and irritants, allergic status, and stress.

CONCLUSIONS

Our observations of work-related upper and lower airway symptoms among hospital workers exposed to vapors from a sporicidal product containing HP, PAA, and AA indicate a need for a combination of engineering, administrative, and PPE controls to reduce exposure. Additionally, alternative nonchemical disinfection technologies should be further investigated as a means to simultaneously reduce healthcare workers' exposure to disinfectants while also minimizing costly healthcare-acquired infections.

Occupational risk factors and exposure-response relationships for airway disease among health workers exposed to cleaning agents in tertiary hospitals

OBJECTIVES

This study investigated occupational risk factors and exposure-response relationships for airway disease among health workers (HWs) exposed to cleaning agents in two tertiary hospitals in South Africa and Tanzania.

METHODS

In this cross-sectional study, 697 participants completed questionnaire interviews while 654 underwent fractional exhaled nitric oxide (FeNO) testing. Asthma Symptom Score (ASS) was computed based on the sum of answers to five questions on asthma-related symptoms in the past 12 months. For exposure-response analyses, cleaning agent-related self-reported exposure variables were categorised into three levels (cleaning product not used; use of a cleaning product for up to 99 min per week and use of a cleaning product for ≥100 min per week).

RESULTS

Asthma-related outcomes (ASS and FeNO) demonstrated positive associations with medical instrument cleaning agents (orthophthalaldehyde and enzymatic cleaners) and tasks (instruments precleaning and changing sterilisation solutions) as well as patient care activities (disinfection prior to procedures and disinfecting wounds). A particularly pronounced dose-response relationship was observed between work-related ocular-nasal symptoms and medical instrument cleaning agents (orthophthalaldehyde, glutaraldehyde, enzymatic cleaners, alcohols and bleach) (OR range: 2.37-4.56) and tasks (OR range: 2.92-4.44). A strong association was also observed between ASS and use of sprays for fixed surface cleaning (mean ratio 2.81; 95% CI 1.41 to 5.59).

CONCLUSIONS

Specific agents for medical instrument disinfection for example, orthophthalaldehyde and enzymatic cleaners, patient care activities and use of sprays are important occupational risk factors for airway disease among HWs.

Free Radicals and Obesity-Related Chronic Inflammation Contrasted by Antioxidants: A New Perspective in Coronary Artery Disease

We are surrounded by factors called free radicals (FR), which attach to the molecules our body is made of, first among them the endothelium. Even though FR are to a certain extent a normal factor, nowadays we face an escalating increase in these biologically aggressive molecules. The escalating formation of FR is linked to the increased usage of man-made chemicals for personal care (toothpaste, shampoo, bubble bath, etc.), domestic laundry and dish-washer detergents, and also an ever wider usage of drugs (both prescription and over the counter), especially if they are to be used long-term (years). In addition, tobacco smoking, processed foods, pesticides, various chronic infectious microbes, nutritional deficiencies, lack of sun exposure, and, finally, with a markedly increasing impact, electromagnetic pollution (a terribly destructive factor), can increase the risk of cancer, as well as endothelial dysfunction, owing to the increased production of FR that they cause. All these factors create endothelial damage, but the organism may be able to repair such damage thanks to the intervention of the immune system supported by antioxidants. However, one other factor can perpetuate the state of inflammation, namely obesity and metabolic syndrome with associated hyperinsulinemia. In this review, the role of FR, with a special emphasis on their origin, and of antioxidants, is explored from the perspective of their role in causing atherosclerosis, in particular at the coronary level.

Indoor and outdoor air quality impacts of cooking and cleaning emissions from a commercial kitchen

Gas and particulate emissions from commercial kitchens are important contributors to urban air quality. Not only are these emissions important for occupational exposure of kitchen staff, but they can also be vented to outdoors, causing uncertain health and environmental impacts. In this study, we chemically speciated volatile organic compounds and measured particulate matter mass concentrations in a well-ventilated commercial kitchen for two weeks, including during typical cooking and cleaning operations. From cooking, we observed a complex mixture of volatile organic gases dominated by oxygenated compounds commonly associated with the thermal degradation of cooking oils. Gas-phase chemicals existed at concentrations 2-7 orders of magnitude lower than their exposure limits, due to the high ventilation in the room (mean air change rate of 28 h^-1 during operating hours). During evening kitchen cleaning, we observed an increase in the signal of chlorinated gases from 1.1-9.0 times their values during daytime cooking. Particulate matter mass loadings tripled at these times. While exposure to cooking emissions in this indoor environment was reduced effectively by the high ventilation rate, exposure to particulate matter and chlorinated gases was elevated during evening cleaning periods. This emphasizes the need for careful consideration of ventilation rates and methods in commercial kitchen environments during all hours of kitchen operation.

Job and exposure intensity among hospital cleaning staff adversely affects respiratory health

BACKGROUND

Occupational exposure to various types of cleaning agents may increase the risk of adverse respiratory health among cleaners. This study investigated the relationship between exposure to cleaning and disinfecting agents, using a job-task and exposure intensity metric, and respiratory outcomes among cleaners.

METHODS

A sample of 174 cleaners was selected from three public hospitals in Durban. A questionnaire was used to collect demographic and occupational information, and spirometry, including post-bronchodilator measures, was conducted according to the American Thoracic Society guidelines and skin prick testing were performed. Exposure metrics for job tasks and chemical exposures were created using frequency and employment-lifetime duration of exposure. Multivariate analysis regression models used job task and exposure intensity metrics.

RESULTS

Doctor-diagnosed asthma prevalence was 9.8%. Breathlessness with wheeze (22.4%) was the prevalent respiratory symptom. Positive responses to skin prick testing were seen in 74 (43.2%). There was a statistically significant increased risk for shortness of breath with exposure to quaternary ammonium compounds (odds ratio [OR]: 3.44; 95% confidence interval [CI]: 1.13-10.5) and breathlessness with exposure to multipurpose cleaner (OR: 0.34; CI: 0.12-0.92). The losses in percent-predicted forced expiratory volume in 1 s (FEV1) ranged from 0.3%-6.7%. Results among the bronchodilator-positive (8.6%) showed lung function losses twofold greater when compared to the total study population with percentage predicted FEV1 (-22.6 %; p < 0.000).

CONCLUSION

Exposure to certain cleaning and disinfectant agents adversely affects respiratory health, particularly lung function. This effect, while seen generally among cleaning workers, is more pronounced among those with pre-existing reversible obstructive lung disease.

Gut epithelial barrier damage caused by dishwasher detergents and rinse aids

BACKGROUND

The increased prevalence of many chronic inflammatory diseases linked to gut epithelial barrier leakiness has prompted us to investigate the role of extensive use of dishwasher detergents, among other factors.

OBJECTIVE

We sought to investigate the effects of professional and household dishwashers, and rinse agents, on cytotoxicity, barrier function, transcriptome, and protein expression in gastrointestinal epithelial cells.

METHODS

Enterocytic liquid-liquid interfaces were established on permeable supports, and direct cellular cytotoxicity, transepithelial electrical resistance, paracellular flux, immunofluorescence staining, RNA-sequencing transcriptome, and targeted proteomics were performed.

RESULTS

The observed detergent toxicity was attributed to exposure to rinse aid in a dose-dependent manner up to 1:20,000 v/v dilution. A disrupted epithelial barrier, particularly by rinse aid, was observed in liquid-liquid interface cultures, organoids, and gut-on-a-chip, demonstrating decreased transepithelial electrical resistance, increased paracellular flux, and irregular and heterogeneous tight junction immunostaining. When individual components of the rinse aid were investigated separately, alcohol ethoxylates elicited a strong toxic and barrier-damaging effect. RNA-sequencing transcriptome and proteomics data revealed upregulation in cell death, signaling and communication, development, metabolism, proliferation, and immune and inflammatory responses of epithelial cells. Interestingly, detergent residue from professional dishwashers demonstrated the remnant of a significant amount of cytotoxic and epithelial barrier-damaging rinse aid remaining on washed and ready-to-use dishware.

CONCLUSIONS

The expression of genes involved in cell survival, epithelial barrier, cytokine signaling, and metabolism was altered by rinse aid in concentrations used in professional dishwashers. The alcohol ethoxylates present in the rinse aid were identified as the culprit component causing the epithelial inflammation and barrier damage.

The effect of hydrochloric acid and sodium hypochlorite on fracture resistance of orthodontic self-cure acrylic base

BACKGROUND

Patient cooperation is necessary for treatment success in removable orthodontics. Every factor has an adverse effect on appliances appearance can impede appliance wearing. This study investigated the effect of immersion in household cleaner and bleach liquids on fracture resistance of self-cure orthodontic acrylic resins.

MATERIALS AND METHODS

This in vitro study two orthodontic acrylic resins (Megadental^® and Acropars^®) were used. Eighty identical acrylic samples (50 mm × 5 mm × 3 mm) from each acrylic resin were fabricated and divided into four groups (n = 20). For each type of acrylic resin; Group 1: 15 min immersion in household cleaner liquid (hydrochloric acid [HCl], 10%), 1 min rinsing with running water, 15 min immersion in household bleach liquid (sodium hypochlorite [NaOCl], 5.25%) and 1 min rinsing with running water were done. For Group 2, two times and for Group 3, three times immersion just like Group 1, were done. Group 4, as control, had no immersion. Fracture resistance of samples was measured with universal testing machine (Instron) in 3-point bending set-up. Data were analyzed with two-way repeated measurement ANOVA. Significance level was set at 0.05.

RESULTS

Fracture resistance of Acropars groups was greater than counterpart Megadental ones (P < 0.001). Immersion factor, alone (P = 0.375) and in combination with material (P = 0.603), did not make a significant difference among fracture resistance of each acrylic resin groups.

CONCLUSION

15 min immersion in household cleaner liquid (HCl acid) followed by 15 min immersion in household bleach liquid (NaOCl 5.25%) and even 3 times repetition of this process had not significant adverse effect on fracture resistance of acrylic resins.

Quaternary ammonium compounds in hypersensitivity reactions

Quaternary ammonium compounds (QAC) are commonly used disinfectants, antiseptics, preservatives, and detergents due to their antibacterial property and represent the first used biocides before phenolic or nitrogen products. Their common structure consists of one or more quaternary ammonium bound with four lateral substituents. Their amphiphilic structure allows them to intercalate into microorganism surfaces which induces an unstable and porous membrane that explains their antimicrobial activity towards bacteria, fungi, and viruses. QAC are thus found in many areas, such as household products, medicines, hygiene products, cosmetics, agriculture, or industrial products but are also used in medical practice as disinfectants and antiseptics and in health care facilities where they are used for cleaning floors and walls. QAC exposure has already been involved in occupational asthma in healthcare workers or professional cleaners by many authors. They also have been suggested to play a role in contact dermatitis (CD) and urticaria in workers using cosmetics such as hairdressers or healthcare workers, inciting reglementary agencies to make recommendations regarding those products. However, distinguishing the irritant or sensitizing properties of chemicals is complex and as a result, the sensitizing property of QAC is still controverted. Moreover, the precise mechanisms underlying the possible sensitization effect are still under investigation, and to date, only a few studies have documented an immunological mechanism. Besides, QAC have been suggested to be responsible for neuromuscular blocking agents (NMBA) sensitization by cross-reactivity. This hypothesis is supported by a higher prevalence of quaternary ammonium (QA)-specific IgE in the professionally exposed populations, such as hairdressers, cleaners, or healthcare workers, suggesting that the sensitization happens with structurally similar compounds present in the environment. This review summarizes the newest knowledge about QAC and their role in hypersensitivities. After describing the different QAC, their structure and use, the most relevant studies about the effects of QAC on the immune system will be reviewed and discussed.

Household use of green and homemade cleaning products, wipe application mode, and asthma among French adults from the CONSTANCES cohort

While exposure to irritant and sprayed cleaning products at home is known to have a harmful role in asthma, the potential health effect of other categories or forms has not been investigated. We studied the associations of household use of cleaning products, including green, homemade products, and disinfecting wipes, with asthma based on data from the large French population-based CONSTANCES cohort. Participants completed standardized questionnaires on respiratory health and household use of cleaning products. Cross-sectional associations of cleaning products with current asthma, adjusted for gender, age, smoking status, BMI, and educational level, were evaluated by logistic regressions. Analyses were conducted in 41 570 participants (mean age: 47 years, 56% women, weekly use of the six specific products/forms studied varied from 11% to 37%). Weekly use of irritants (OR = 1.23 [1.13-1.35]), scented (OR = 1.15 [1.06-1.26]), green (OR = 1.09 [1.00-1.20]), and homemade products (OR = 1.19 [1.06-1.34]), as well as sprays (OR = 1.18 [1.08-1.29]), disinfecting wipes (OR = 1.21 [1.09-1.34]) were significantly associated with asthma, with significant trends according to the frequency of use. When they were not co-used with irritants/sprays, associations were reduced and persisted only for disinfecting wipes. Weekly use of disinfecting wipes at home was associated with current asthma, but fewer risks were observed for the use of green and homemade products.

Morbidity and mortality in obsessive-compulsive disorder: A narrative review

Current knowledge on the general somatic health of individuals with obsessive-compulsive disorder (OCD) is very limited. Here, we critically review the emerging literature on the topic. Rapidly accumulating evidence indicates an association between OCD and autoimmune diseases, which is not limited to streptococcus-related conditions. Similarly, an association with metabolic and circulatory system diseases has been reported, which is at least partially independent from psychiatric comorbidities and familial confounders. Preliminary results also suggest potential links with dementia, insomnia, respiratory diseases, gastrointestinal diseases, migraine, and chronic pain, but replication is warranted. The risk of death by suicide in OCD is now well established. OCD has also been associated to increased mortality due to natural causes, but more research on specific causes of death is needed. Clarification of the mechanisms behind the observed associations will be critical to inform the rational design of prevention efforts. In the meantime, while OCD symptom reduction remains a priority, clinicians should also focus on monitoring the general health and promoting healthy lifestyles of persons with OCD.

Blood absorption toxicokinetics of glycol ethers after inhalation: A human controlled study

Glycol ethers are organic solvents present in countless products for professional and domestic use. The main toxicological concerns are hematotoxicity, respiratory and reproductive toxicity. The general population can be exposed when using products containing one or several glycol ethers that evaporate or if sprayed, generate aerosols that can be inhaled. The rate at which glycol ethers enters blood following inhalation exposure are unknown in humans, and chemical risk assessors only rely on animal and in vitro toxicity studies. Propylene glycol monomethyl ether (PGME) and propylene glycol monobutyl ether (PGBE) are two examples of glycol ethers used worldwide. Our study aimed to provide human toxicokinetic data after inhalation exposure of low PGME and PGBE concentrations tested alone or in mixture. Healthy participants (n = 28) were exposed to 35 ppm (131 mg/m³) of PGME and 15 ppm (i.e., 83 mg/m³) of PGBE for 2 or 6 h. Blood was regularly collected during the exposure sessions. PGME and PGBE were immediately bioavailable in blood during exposure, and the mean absorption rates were up to 13 μg/L/min and 2.45 μg/L/min, respectively. Maximum mean blood concentration (Cmax) was 2.91 mg/L and 0.41 mg/L for PGME and PGBE. The cumulative internal doses over time (area under the curve, AUC) were 11 mg∗h/L and 1.81 mg∗h/L for PGME and PGBE. PGME and PGBE total blood uptake could possibly be higher in physically active individuals, such as workers. We recommend that glycol ethers present on the market undergo toxicological testing with the internal doses we found in our toxicokinetic study.

Occupational Exposures and Lung Cancer Risk-An Analysis of the CARTaGENE Study

OBJECTIVE

To determine the associations between prevalent occupational agents and lung cancer risk.

METHODS

A case-cohort design (ncases= 147; nsub-cohort= 1,032) was nested within the CARTaGENE prospective cohort study. The Canadian Job Exposure Matrix was used to determine the probability of exposure to 27 agents in participants' longest-held jobs. Multivariable logistic regression with robust variance estimators was used to determine the associations between each agent and lung cancer risk while adjusting for established lung cancer risk factors.

RESULTS

Increased lung cancer risk was observed among those exposed to ashes, calcium sulfate, formaldehyde, cooking fumes, alkanes, aliphatic aldehydes, and cleaning agents. Lower lung cancer risk was found among participants exposed to carbon monoxide and polycyclic aromatic hydrocarbons from petroleum.

CONCLUSION

Our findings support the role of several occupational agents, for which we have limited knowledge, in contributing to lung cancer risk.

Identifying cleaning products associated with short-term work-related respiratory symptoms: A workforce-based study in domestic cleaners

Domestic cleaners have an increased risk of asthma-like and other respiratory symptoms and conditions. Uncertainty exists about which products are most hazardous. We aimed to investigate, among professional domestic cleaners, the associations of ocular/respiratory outcomes with using specific types of products at work and with the ability to choose their own products. Among domestic cleaners employed by "service vouchers" companies in Belgium, we administered an online questionnaire on ocular/respiratory symptoms (frequency and time relation to workdays), frequency of use of 40 types of products, and ability to choose one's own products. Work-relatedness was defined as symptoms improving/disappearing on days off-work. We studied associations between frequency of product-use with work-related outcomes (eye irritation, rhinitis symptoms, sore throat, laryngeal symptoms, asthma symptoms, cough) and with chronic bronchitis, using multivariable logistic and elastic net regression. Adjusted odds ratios (OR) with 95%-confidence intervals were obtained per time a product was used per week. Among 1,586 domestic cleaners (99% women), the number of times sprays were used (median 13/week) was significantly associated with all outcomes (ORs between 1.012 and 1.024 per time sprays were used per week). Bleach/disinfectant-containing liquid products were associated with all outcomes, except for laryngeal symptoms (ORs 1.086 to 1.150); ammonia with work-related upper airway symptoms and chronic bronchitis. Cleaners able to choose their own products had fewer work-related eye symptoms (OR 0.728;0.556-0.954), rhinitis (OR 0.735;0.571-0.946) and cough (OR 0.671;0.520-0.865). Using elastic net regression, work-related rhinitis was most strongly associated with mould removal spray (OR 1.108;1.006-1.248), carpet/seat/curtain spray (OR 1.099;1.001-1.304) and ammonia (OR 1.081;1.002-1.372); work-related asthma with carpet/seat/curtain spray (OR 1.103;1.017-1.322), mould removal spray (OR 1.029;0.995-1.199) and drain cleaner (OR 1.023;0.979-1.302). In a large group of domestic cleaners, we documented that cleaning products have a range of adverse respiratory effects. Empowering cleaners to choose their products may reduce the burden of symptoms.

A pilot study of total personal exposure to volatile organic compounds among Hispanic female domestic cleaners

Cleaners have an elevated risk for the development or exacerbation of asthma and other respiratory conditions, possibly due to exposure to cleaning products containing volatile organic compounds (VOCs) leading to inflammation and oxidative stress. This pilot study aimed to quantify total personal exposure to VOCs and to assess biomarkers of inflammation and pulmonary oxidative stress in 15 predominantly Hispanic women working as domestic cleaners in San Antonio, Texas, between November 2019 and July 2020. In partnership with a community organization, Domésticas Unidas, recruited women were invited to attend a training session where they were provided 3M 3500 passive organic vapor monitors (badges) and began a 72-hr sampling period during which they were instructed to wear one badge during the entire period ("AT," for All the Time), a second badge only while they were inside their home ("INS," for INSide), and a third badge only when they were outside their home ("OUT," for OUTside). At the end of the sampling period, women returned the badges and provided blood and exhaled breath condensate (EBC) samples. From the badges, 30 individual VOCs were measured and summed to inform total VOC (TVOC) concentrations, as well as concentrations of the following VOC groups: aromatic hydrocarbons, alkanes, halogenated hydrocarbons, and terpenes. From the blood and EBC samples, concentrations of serum C-reactive protein (CRP) and EBC 8-isoprostane (8-ISP) and pH were quantified. Data analyses included descriptive statistics. The 72-hr average of personal exposure to TVOC was 34.4 ppb and ranged from 9.2 to 219.5 ppb. The most prevalent class of VOC exposures for most women (66.7%) was terpenes, specifically d-limonene. Overall, most women also experienced higher TVOC concentrations while outside their home (86.7%) as compared to inside their home. Serum CRP concentrations ranged from 0.3 to 20.3 mg/dL; 8-ISP concentrations ranged from 9.5 to 44.1 pg/mL; and EBC pH ranged from 7.1 to 8.6. Overall, this pilot study demonstrated personal VOC exposure among Hispanic domestic cleaners, particularly to d-limonene, which may result from the use of scented cleaning products.

Does the epithelial barrier hypothesis explain the increase in allergy, autoimmunity and other chronic conditions?

There has been a steep increase in allergic and autoimmune diseases, reaching epidemic proportions and now affecting more than one billion people worldwide. These diseases are more common in industrialized countries, and their prevalence continues to rise in developing countries in parallel to urbanization and industrialization. Intact skin and mucosal barriers are crucial for the maintenance of tissue homeostasis as they protect host tissues from infections, environmental toxins, pollutants and allergens. A defective epithelial barrier has been demonstrated in allergic and autoimmune conditions such as asthma, atopic dermatitis, allergic rhinitis, chronic rhinosinusitis, eosinophilic esophagitis, coeliac disease and inflammatory bowel disease. In addition, leakiness of the gut epithelium is also implicated in systemic autoimmune and metabolic conditions such as diabetes, obesity, multiple sclerosis, rheumatoid arthritis, systemic lupus erythematosus, ankylosing spondylitis and autoimmune hepatitis. Finally, distant inflammatory responses due to a 'leaky gut' and microbiome changes are suspected in Alzheimer disease, Parkinson disease, chronic depression and autism spectrum disorders. This article introduces an extended 'epithelial barrier hypothesis', which proposes that the increase in epithelial barrier-damaging agents linked to industrialization, urbanization and modern life underlies the rise in allergic, autoimmune and other chronic conditions. Furthermore, it discusses how the immune responses to dysbiotic microbiota that cross the damaged barrier may be involved in the development of these diseases.

E-Cadherin: An Important Functional Molecule at Respiratory Barrier Between Defence and Dysfunction

While breathing, many microorganisms, harmful environmental particles, allergens, and environmental pollutants enter the human airways. The human respiratory tract is lined with epithelial cells that act as a functional barrier to these harmful factors and provide homeostasis between external and internal environment. Intercellular epithelial junctional proteins play a role in the formation of the barrier. E-cadherin is a calcium-dependent adhesion molecule and one of the most important molecules involved in intercellular epithelial barier formation. E-cadherin is not only physical barrier element but also regulates cell proliferation, differentiation and the immune response to environmental noxious agents through various transcription factors. In this study, we aimed to review the role of E-cadherin in the formation of airway epithelial barier, its status as a result of exposure to various environmental triggers, and respiratory diseases associated with its dysfunction. Moreover, the situations in which its abnormal activation can be noxious would be discussed.

Quantification and source characterization of volatile organic compounds from exercising and application of chlorine-based cleaning products in a university athletic center

Humans spend approximately 90% of their time indoors, impacting their own air quality through occupancy and activities. Human VOC emissions indoors from exercise are still relatively uncertain, and questions remain about emissions from chlorine-based cleaners. To investigate these and other issues, the ATHLETic center study of Indoor Chemistry (ATHLETIC) campaign was conducted in the weight room of the Dal Ward Athletic Center at the University of Colorado Boulder. Using a Vocus Proton-Transfer-Reaction Time-of-Flight Mass Spectrometer (Vocus PTR-TOF), an Aerodyne Gas Chromatograph (GC), an Iodide-Chemical Ionization Time-of-Flight Mass Spectrometer (I-CIMS), and Picarro cavity ringdown spectrometers, we alternated measurements between the weight room and supply air, allowing for determination of VOC, NH₃ , H₂ O, and CO₂ emission rates per person (emission factors). Human-derived emission factors were higher than previous studies of measuring indoor air quality in rooms with individuals at rest and correlated with increased CO₂ emission factors. Emission factors from personal care products (PCPs) were consistent with previous studies and typically decreased throughout the day. In addition, N-chloraldimines were observed in the gas phase after the exercise equipment was cleaned with a dichlor solution. The chloraldimines likely originated from reactions of free amino acids with HOCl on gym surfaces.

Assessing the potential of unmanned aerial vehicle spraying of aqueous ozone as an outdoor disinfectant for SARS-CoV-2

The COVID-19 pandemic has revealed gaps in our understanding of safe, effective and efficient means of disinfecting high use public spaces. Whilst this creates an opportunity for development and application of innovative approaches such as unmanned aerial vehicle (UAV) based disinfection, unregulated outdoor disinfection using chlorine has led to environmental and public health risks. This study has quantified the efficiency, safety and efficacy of UAV-based spraying of aqueous ozone. Optimised UAV flight characteristics of 4.7 km/h at 1.7 m elevation spraying 2.4 L/min were able to provide >97% and >92% coverage of a 1 m and 2 m wide swath respectively. During spraying operations using 1 mg/L aqueous ozone, atmospheric concentrations of ozone remained within background levels (<0.04 ppm). Highly efficient inactivation of two different isolates of SARS-CoV-2 virus was achieved at aqueous ozone concentrations of 0.75 mg/L after an incubation period of only 5 min, with 0.375 mg/L achieving 82-91.5% inactivation in this time. Exposure of diamondback moth larvae and parasitic wasps to 1 mg/L aqueous ozone did not significantly affect their survivorship. These results indicate for the first time that aqueous ozone may provide the required balance between human and environmental safety and viral inactivation efficacy for targeted application in high risk outdoor settings.

Occupational Asthma Caused by Quaternary Ammonium Compounds: A Multicenter Cohort Study

BACKGROUND

Quaternary ammonium compounds (QACs) are used extensively for cleaning and disinfection and have been documented in scattered reports as a cause of occupational asthma (OA) through bronchoprovocation tests (BPTs).

OBJECTIVE

To examine the clinical, functional, and inflammatory profile of QAC-induced OA compared with OA caused by other low-molecular weight (LMW) agents.

METHODS

The study was conducted in a retrospective multicenter cohort of 871 subjects with OA ascertained by a positive BPT. Subjects with QAC-induced OA (n = 22) were identified based on a positive BPT to QACs after exclusion of those challenged with cleaning products or disinfectants that contained other potential respiratory sensitizers. They were compared with 289 subjects with OA caused by other LMW agents.

RESULTS

Most subjects with QAC-induced OA were working in the health care sector (n = 14). A twofold or greater increase in the postchallenge level of nonspecific bronchial hyperresponsiveness was recorded in eight of 11 subjects with QAC-induced OA (72.7%) and in 49.7% of those with OA caused by other LMW agents. Although sputum assessment was available in only eight subjects with QAC-induced OA, they showed a significantly greater median (interquartile) increase in sputum eosinophils (18.1% [range, 12.1% to 21.1%]) compared with those with OA caused by other LMW agents (2.0% [range, 0% to 5.2%]; P < .001).

CONCLUSIONS

This study indicates that QAC-induced OA is associated with a highly eosinophilic pattern of airway response and provides further evidence supporting the sensitizing potential of QACs. The findings highlight the heterogeneous nature of the pathobiologic pathways involved in OA caused by LMW agents.

Development of a personal passive air sampler for estimating exposure to effective chlorine while using chlorine-based disinfectants

With an increasing use of indoor disinfectants such as chlorine (Cl₂ ) and hypochlorous acid, a convenient sampler for estimating exposure to oxidants, such as effective chlorine, is necessary. Here, we developed a personal passive air sampler (PPAS) composed of a redox dye, o-dianisidine, in a polydimethylsiloxane (PDMS) sheet. o-Dianisidine readily reacts with gaseous oxidants generated by bleach usage, and its color changes as the reaction progresses; hence, personal exposure to effective chlorine could be easily detected by the naked eye, while cumulative exposure could be determined by measuring concentrations of o-dianisidine reacting with it. The PPAS was calibrated, and a sampling rate of 0.00253 m³ /h was obtained using a small test chamber. The PPAS was tested with the help of ten volunteers whose personal exposure to Cl₂ -equivalent gas was estimated after bathrooms were cleaned using spray and liquid-type household disinfection products, and the accumulated exposure-gas concentrations ranged from 69 to 408 ppbv and 148 to 435 ppbv, respectively. These PPAS-derived exposure concentrations were approximately two orders lower than those estimated using ConsExpo, suggesting a significant overestimation by prevailing screening models, possibly due to the ignorance of transformation reactions.

Environmental factors in epithelial barrier dysfunction

The main interfaces controlling and attempting to homeostatically balance communications between the host and the environment are the epithelial barriers of the skin, gastrointestinal system, and airways. The epithelial barrier constitutes the first line of physical, chemical, and immunologic defenses and provides a protective wall against environmental factors. Following the industrial revolution in the 19th century, urbanization and socioeconomic development have led to an increase in energy consumption, and waste discharge, leading to increased exposure to air pollution and chemical hazards. Particularly after the 1960s, biological and chemical insults from the surrounding environment-the exposome-have been disrupting the physical integrity of the barrier by degrading the intercellular barrier proteins at tight and adherens junctions, triggering epithelial alarmin cytokine responses such as IL-25, IL-33, and thymic stromal lymphopoietin, and increasing the epithelial barrier permeability. A typical type 2 immune response develops in affected organs in asthma, rhinitis, chronic rhinosinusitis, eosinophilic esophagitis, food allergy, and atopic dermatitis. The aim of this article was to discuss the effects of environmental factors such as protease enzymes of allergens, detergents, tobacco, ozone, particulate matter, diesel exhaust, nanoparticles, and microplastic on the integrity of the epithelial barriers in the context of epithelial barrier hypothesis.

Respiratory Health Effects of Exposure to Cleaning Products

There is consistent and growing evidence of an epidemic of "asthma-like" symptoms among professional cleaners. Questions include how big is this problem worldwide, which cleaning agents are dangerous, how do they affect the lungs, and is it really asthma? This issue is important to public health because of the increasing number of professional cleaners, many from vulnerable categories. There are implications for anybody exposed to cleaning products during housekeeping, including children. This article uses available evidence to give a broad but concise overview on what we know so far and how we can prevent the cleaning-associated respiratory public health burden.

Effects of Chlorine Gas Exposure and Associated Factors on Spirometric Parameters in Detergent Industry Workers: a Four-Year Cross-Sectional Study

BACKGROUND

This study aimed to determine the effects of chlorine gas exposure and the associated factors on spirometric parameters among detergent industry workers in Semnan, Iran.

MATERIALS AND METHODS

This four-year cross-sectional study was concocted on 100 workers of two detergent factories in Semnan, Iran. Two questionnaires were used for data collection. The first questionnaire included demographic and occupational information, and the second questionnaire included spirometric parameters, such as forced vital capacity (FVC), forced expiratory volume in one second (FEV1), FEV1/FVC ratio, peak expiratory flow (PEF), and PEF 25-75%. The spirometric parameters were measured over four consecutive years by a trained technician. Next, to determine the effects of chlorine gas exposure and its associated factors on spirometric parameters, a generalized estimating equation (GEE) model was used. The correlation structure of GEE was considered to be autoregressive 1 (AR-1). Analyses were performed in STATA version 14.

RESULTS

All spirometric parameters showed a decreasing trend during 2012-2015. The GEE model showed a significant association between chlorine gas exposure and all spirometric parameters; the beta-coefficients for the effect of exposure (year) on FVC, FEV1, FEV1/FVC ratio, PEF, and PEF 25-75% were -4.51, -6.46, -4.27, -6.09, and -10.29, respectively. Also, this model demonstrated a significant association between smoking and FEV1, PEF, and PEF 25-75%; the beta-coefficients for the effect of smoking on these parameters were -5.64, -8.88, and -5.75, respectively. Additionally, the GGE model showed a significant association between the body mass index (BMI) and FVC and FEV1 (P<0.05); the beta-coefficients for the effect of BMI on these two parameters were - 0.59 and -0.48, respectively.

CONCLUSION

The spirometric parameters showed a decreasing trend over time among detergent industry workers; this decline was more remarkable among individuals with a history of smoking. Therefore, it seems necessary to implement screening programs and periodic active examinations for these workers.

Ventilation and posture effects on inhalation exposures to volatile cleaning ingredients in a simulated domestic worker cleaning environment

Associations between cleaning chemical exposures and asthma have previously been identified in professional cleaners and healthcare workers. Domestic workers, including housecleaners and caregivers, may receive similar exposures but in residential environments with lower ventilation rates. Study objectives were to compare exposures to occupational exposure limits (OELs), to determine relative contributions from individual cleaning tasks to overall exposure, and to evaluate the effects of ventilation and posture on exposure. Airborne chemical concentrations of sprayed cleaning chemicals (acetic acid or ammonia) were measured during typical cleaning tasks in a simulated residential work environment. Whole-house cleaning exposures (18 cleaning tasks) were measured using integrated personal sampling methods. Individual task exposures were measured with a sampling line attached to subjects' breathing zones, with readings recorded by a ppbRAE monitor, equipped with a photoionization detector calibrated for ammonia and acetic acid measurements. Integrated sampling results indicated no exposures above OELs occurred, but 95th percentile air concentrations would require risk management decisions. Exposure reductions were observed with increased source distance, with lower exposures from mopping floors compared to kneeling. Exposure reductions were also observed for most but not all tasks when ventilation was used, with implications that alternative exposure reduction methods may be needed.

Cleaning products and respiratory health outcomes in occupational cleaners: a systematic review and meta-analysis

There is consistent evidence of increased respiratory symptoms in occupational cleaners; however, uncertainty remains on type of respiratory health effects, underlying causal agents, mechanisms and respiratory phenotypes. We aimed to conduct a systematic review and if possible, a meta-analysis of the available literature to characterise and quantify the cleaning-related respiratory health effects. We searched MEDLINE and EMBASE databases and included studies that evaluated the association of any respiratory health outcome with exposure to cleaning occupation or products in occupational cleaners. A modified GRADE was used to appraise the quality of included studies. We retrieved 1124 articles, and after applying our inclusion criteria, 39 were selected for the systematic review. We performed a meta-analysis of the 21 studies evaluating asthma which showed a 50% increased pooled relative risk in cleaners (meta-relative risk (RR)=1.50; 95% CI 1.44 to 1.56). Population-based cross-sectional studies showed more stable associations with asthma risk. No evidence of atopic asthma as dominant phenotype emerged. Also, we estimated a 43% increased risk (meta-RR=1.43; 95% CI 1.31 to 1.56) of chronic obstructive pulmonary disease. Evidence for associations with bronchial-hyper-responsiveness, lung function decline, rhinitis, upper and lower respiratory tract symptoms was weaker. In our systematic review and meta-analysis, we found that working as a cleaner is associated with an increased risk of reversible and even irreversible obstructive airway diseases. All studies lacked quantitative exposure assessment to cleaning products; this would help elucidate underlying causal agents and mechanisms. Exposure control and respiratory surveillance among cleaners is warranted to prevent the associated respiratory health burden. Trial registration number: CRD4201705915.

Consequences of chemical impact of disinfectants: safe preventive measures against COVID-19

Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has created a significant threat to global health. It originated in Wuhan, China and caused a total of 83,483 confirmed cases and 4634 deaths until June 2020. This novel virus spread primarily through respiratory droplets and close contact. The person-to-person transmission by direct transmittance through cough, sneeze, droplet inhalation, and contact spreading from dry surfaces contaminated with secretions of nose, mouth, and eyes of an infected person has been proven about SARS-CoV-2 transmission. As disease progressed, a series of complications tends to develop, especially in critically ill and immunocompromised patients. Pathological studies showed representative features of acute respiratory distress syndrome (ARDS) and implications on multiple organs as well. However, no specific antiviral drugs or vaccines are immediately available for the treatment of this lethal disease. The efficacy of some promising antivirals needs to be investigated by ongoing clinical trials. In current circumstances, supportive care, precautions, and social distancing are the only preventive options to ameliorate COVID-19. To disinfect the environment, mainly chemical disinfectants are being used robustly. However, due to panic state, fright, and unawareness, people are using it violently, which can have an adverse effect on human health and environment. This review discusses about the potential harmful effect of disinfectants, if used inappropriately. Here, we will also discuss safe preventive options as an alternative to robust use of disinfection methods to fight against COVID-19.

Changes in spirometric parameters after protective interventions among workers at a chlorine production plant in Iran

OBJECTIVES

This study was conducted to assess changes in spirometric parameters after protective interventions among workers at a chlorine production plant in Semnan, Iran during 2012-2016.

METHODS

This quasi-experimental study included 100 workers at a chlorine production plant in Semnan during 2012-2016. Spirometric parameters (forced vital capacity [FVC], forced expiratory volume in 1 second [FEV1], FEV1/FVC, peak expiratory flow [PEF], and PEF occurring in the middle 50% of the patient's exhaled volume [PEF 25-75%]) were measured in all workers before the initial intervention in 2012. Protective interventions were then implemented for 4 consecutive years and the parameters were measured annually. A multivariable linear regression model was used to assess the factors affecting spirometric parameters before and after the protective interventions in SPSS version 24.

RESULTS

The mean values of all spirometric parameters significantly increased after the protective interventions (p<0.05). Multivariable linear regression showed that age (β=-0.40), body mass index (BMI) (β=0.71; 95% confidence interval [CI], 0.11 to 1.31), and type of mask (β=-7.88; 95% CI, -15.96 to -0.46) had significant effects on the mean difference in FVC. Similarly, age (β=-0.35; 95% CI, -0.70 to -0.01), BMI (β=0.80; 95% CI, 0.20 to 1.41) and type of mask (β=-8.88; 95% CI, -16.98 to -0.79) had significant associations with the mean difference in FEV1. The type of mask (β=-12.81; 95% CI, -25.01 to -0.60) had a significant effect on the mean difference in PEF.

CONCLUSIONS

All spirometric parameters significantly increased in workers after protective interventions were implemented. Therefore, protective interventions to prevent respiratory disorders in workers exposed to chlorine gas are suggested.

Working Conditions and Work-Related Health Issues of Female Domestic Workers in Four Districts of Karachi

OBJECTIVES

To determine the working conditions and work-related health issues of female domestic workers (FDWs) in four districts of Karachi.

METHODS

Population-based cross-sectional study was conducted in four squatter settlements of Karachi with sample size of 406 FDWs in 2018. Pretested questionnaire was administered to collect data through snowball technique. Multivariate logistic regression examined the association between different factors and experiencing violence, work-related injuries, and chemical exposures.

RESULTS

Only (14.5%) of domestic workers earned Rs 15 000 (75 GBP month-1) and above. >1% had financial support for the health or education of children. Verbal violence included shouting (40.9%), constant critique of work (17.2%), and job threats (13.5%). Common workplace injuries were cuts (30.8%), burns (27.6%), and bruises (23.6%). Doing laundry showed significant positive association with experiencing cuts [odds ratio (OR) = 2.09; 1.15-3.71], looking after children to bruises (OR = 2.29; 1.07-4.88), and cooking to burns (OR = 4.66; 2.68-8.08).

CONCLUSIONS

Creating economic environment which is equal for all low wage workers, setting up domestic labor standards and holding employers accountable to them is essential.

Inactivation of the multi-drug resistant pathogen Candida auris using ultraviolet germicidal irradiation (UVGI)

BACKGROUND

Candida auris, often a multi-drug resistant fungal pathogen, has become an emerging threat in healthcare settings around the world. Reliable disinfection protocols specifically designed to inactivate C. auris are essential, as many chemical disinfectants commonly used in healthcare settings have been shown to have variable efficacy at inactivating C. auris.

AIM

Ultraviolet germicidal irradiation (UVGI) was investigated as a method to inactivate clinically relevant strains of C. auris.

METHODS

Ten C. auris and two C. albicans isolates were exposed to ultraviolet (UV) energy to determine the UV dose required to inactivate each isolate. Using a UV reactor, each isolate (106 cells/mL) was exposed to 11 UV doses ranging from 10-150 mJ/cm2 and then cultured to assess cell viability.

FINDINGS

An exponential decay model was applied to each dose-response curve to determine inactivation rate constants for each isolate, which ranged from 0.108-0.176 cm2/mJ for C. auris and 0.239-0.292 cm2/mJ for C. albicans. As the model of exponential decay did not accurately estimate the dose beyond 99.9% inactivation, a logistic regression model was applied to better estimate the doses required for 99.999% inactivation. Using this model, significantly greater UV energy was required to inactivate C. auris (103 to 192 mJ/cm2) when compared to C. albicans (78 to 80 mJ/cm2).

CONCLUSION

This study demonstrated UVGI as a feasible approach for inactivating C. auris, although variable susceptibility among isolates must be taken into account. This dose-response data is critical for recommending UVGI dosing strategies to be tested in healthcare settings.

Respiratory health in professional cleaners: Symptoms, lung function, and risk factors

BACKGROUND

Cleaning is associated with an increased risk of asthma symptoms, but few studies have measured functional characteristics of airway disease in cleaners.

AIMS

To assess and characterize respiratory symptoms and lung function in professional cleaners, and determine potential risk factors for adverse respiratory outcomes.

METHODS

Symptoms, pre-/post-bronchodilator lung function, atopy, and cleaning exposures were assessed in 425 cleaners and 281 reference workers in Wellington, New Zealand between 2008 and 2010.

RESULTS

Cleaners had an increased risk of current asthma (past 12 months), defined as: woken by shortness of breath, asthma attack, or asthma medication (OR = 1.83, 95% CI = 1.18-2.85). Despite this, they had similar rates of current wheezing (OR = 0.93, 95% CI = 0.65-1.32) and were less likely to have a doctor diagnosis of asthma ever (OR = 0.62, 95% CI = 0.42-0.92). Cleaners overall had lower lung function (FEV₁ , FVC; P < .05). Asthma in cleaners was associated with less atopy (OR = 0.35, 95% CI = 0.13-0.90), fewer wheezing attacks (OR = 0.40, 95% CI = 0.17-0.97; >3 vs ≤3 times/year), and reduced bronchodilator response (6% vs 9% mean FEV₁ -%-predicted change, P < .05) compared to asthma in reference workers. Cleaning of cafes/restaurants/kitchens and using upholstery sprays or liquid multi-use cleaner was associated with symptoms, whilst several exposures were also associated with lung function deficits (P < .05).

CONCLUSIONS AND CLINICAL RELEVANCE

Cleaners are at risk of some asthma-associated symptoms and reduced lung function. However, as it was not strongly associated with wheeze and atopy, and airway obstruction was less reversible, asthma in some cleaners may represent a distinct phenotype.

Multiphase Chemistry Controls Inorganic Chlorinated and Nitrogenated Compounds in Indoor Air during Bleach Cleaning

We report elevated levels of gaseous inorganic chlorinated and nitrogenated compounds in indoor air while cleaning with a commercial bleach solution during the House Observations of Microbial and Environmental Chemistry field campaign in summer 2018. Hypochlorous acid (HOCl), chlorine (Cl₂), and nitryl chloride (ClNO₂) reached part-per-billion by volume levels indoors during bleach cleaning-several orders of magnitude higher than typically measured in the outdoor atmosphere. Kinetic modeling revealed that multiphase chemistry plays a central role in controlling indoor chlorine and reactive nitrogen chemistry during these periods. Cl₂ production occurred via heterogeneous reactions of HOCl on indoor surfaces. ClNO₂ and chloramine (NH₂Cl, NHCl₂, NCl₃) production occurred in the applied bleach via aqueous reactions involving nitrite (NO₂^-) and ammonia (NH₃), respectively. Aqueous-phase and surface chemistry resulted in elevated levels of gas-phase nitrogen dioxide (NO₂). We predict hydroxyl (OH) and chlorine (Cl) radical production during these periods (10⁶ and 10⁷ molecules cm^-3 s^-1, respectively) driven by HOCl and Cl₂ photolysis. Ventilation and photolysis accounted for <50% and <0.1% total loss of bleach-related compounds from indoor air, respectively; we conclude that uptake to indoor surfaces is an important additional loss process. Indoor HOCl and nitrogen trichloride (NCl₃) mixing ratios during bleach cleaning reported herein are likely detrimental to human health.

Anti-oxidant and Anti-inflammatory Effects of Aquatic Exercise in Allergic Airway Inflammation in Mice

Oxidative stress and inflammation are key pathways responsible for the pathogenesis of asthma. Aquatic exercise (AE) has been proven to elicit a variety of biological activities such as anti-oxidant and anti-inflammatory effects. However, although proper forms of AE provide beneficial health effects, incorrect forms and types of AE are potentially injurious to health. Several studies have investigated AE, but the relationship between types of AE and asthma has not been fully elucidated. This study evaluated the effects of two types of AE according to resistance on ovalbumin (OVA)-induced allergic airway inflammation in mice. BALB/c mice were subjected to OVA sensitization and challenge, and then to different types of AE including, walking and swimming, in a pool filled with water to a height of 2.5 and 13 cm for 30 min, respectively. AE reduced OVA-induced eosinophilic inflammation, airway hyperresponsiveness, and serum immunoglobulin E level. AE significantly inhibited increases in interleukin (IL)-4, IL-5, IL-13, histamine, leukotriene D4, and tryptase levels in bronchoalveolar lavage fluid (BALF). AE also effectively suppressed mucus formation, lung fibrosis, and hypertrophy of airway smooth muscle within the lung tissues. This exercise markedly reduced the levels of malondialdehyde while increased glutathione and superoxide dismutase (SOD) activity in lung tissues. Furthermore, AE significantly decreased tumor necrosis factor-α, IL-6 levels, and prostaglandin E2 production in BALF. The inhibitory effects of swimming on the levels of biomarkers related to oxidative stress and inflammation were greater than that of walking. These effects may have occurred through upregulation of NF-E2-related factor 2/heme oxygenase-1 signaling and suppression of mitogen-activated protein kinase/nuclear factor-κB pathway. Cumulative results from this study suggest that AE might be beneficial in mitigating the levels of biomarkers related to oxidative stress and inflammation. Thus, this therapy represents a crucial non-pharmacological intervention for treatments of allergic airway inflammation.

Characterization of airborne particles from cleaning sprays and their corresponding respiratory deposition fractions

Cleaning workers are exposed to many risk factors, including handling of cleaning products. Epidemiological studies show that they have a high incidence of asthma and other respiratory symptoms. Some studies have indicated an even higher incidence of asthma in individuals using cleaning sprays regularly. It is known that sprays produce an aerosol that can expose the respiratory system to chemicals. Knowledge of the physical characteristics of the airborne particles, as well as the characteristics of the gas phase, is needed to determine how they affect the respiratory tract and why they cause airway symptoms. The aim of this study was to characterize the aerosols from seven different ready-to-use trigger cleaning sprays in terms of total airborne mass fraction, particle size distribution, and new particle formation from ozone reactions. An additional aim was to calculate the respiratory deposition fraction of the measured particles. The total airborne mass fraction was determined by comparing the mass deposited on the chamber wall with the mass emitted from the bottle during spraying. Particle number concentration and size distribution of the airborne particles were measured using an aerodynamic particle sizer and a fast aerosol mobility size spectrometer. The total airborne mass fraction was between 2.7% and 32.2% of the mass emitted from the bottle, depending on the product. Between 0.0001% and 0.01% of the total airborne mass fraction consisted of residual particles. However, these particles had a mass median aerodynamic diameter between 1.9 µm and 3.7 µm, constituting a total respiratory deposition of up to 77%. New particle formation in the presence of ozone was also shown to vary between 5,000 cm^-3 and 35,000 cm^-3 depending on the product, in the studied settings. These findings confirm that a substantial part (up to 1/3) of the mass sprayed from the bottle does not reach the intended surface. Thus, the use of cleaning sprays can result in chemical airway exposure, with particles in the relevant size range for both nasal and alveolar deposition.

Work-Related Symptoms of Patients with Asthma: A Multicenter Study

OBJECTIVES

It is considered that occupational exposure accounts for up to 25% of all cases of adult asthma. We need detailed individual-level data regarding the relationship between asthma, occupation, and work-related symptoms in Turkey to inform policies on workplace safety. This study aimed to investigate the association between asthma symptoms, occupation type, and workplace exposure in patients with asthma.

MATERIALS AND METHODS

In this cross-sectional multicenter study, adult patients with asthma were investigated by a questionnaire in terms of relationship between asthma symptoms and workplace exposure. The study population was adult patients who had been diagnosed with asthma for at least six months prior to study and who were under follow-up in Ankara, İstanbul, Erzurum, Düzce, Trabzon, Denizli, and Diyarbakır.

RESULTS

The mean age of the 345 cases (188 females) was 41±13 years. The majority of the patients (36.8%) were "housewives"; other common occupations were office workers (6.7%), textile workers (4%), students (3.8%), hospital staff (3.5%), and cleaners (2.9%). Thirty-five percent of patients described worsening of asthma during working periods. Among patients with a history of increased symptoms in workplace, 100 (83%) developed asthma after starting work, while 20 patients (17%) had pre-existing asthma. Half of the patients described workplace exposure to dust, fume, and gases. Exposure to cleaning supplies at home was present in 43% of the subjects. Of all housewives, 12% (n=15) described an increase in their asthma symptoms during housework. The frequency of bleach or hydrochloric acid use alone among housewives was 60% and 34%, which was significantly higher than other occupations. The FEV₁/FVC ratio of housewives who frequently used hydrochloric acid (FEV₁/FVC=71.5) was lower than that of non-users (FEV₁/FVC=74.9) (p=0.024).

CONCLUSION

Patients with asthma experience significant workplace exposures that exacerbate their symptoms. Housewives experience significant exposure that triggers allergic and asthma symptoms. It is important to raise awareness about the prevalence and risks of occupational (including in-home) exposures in asthmatics patients and physicians to minimize asthma triggers and exacerbations.

Use of cleaning agents at home and respiratory and allergic symptoms in adolescents: The PIAMA birth cohort study

BACKGROUND

It has been suggested that adults who use cleaning agents in their homes have a higher risk of asthma and allergic symptoms. The associations of asthma and allergic symptoms with household use of cleaning agents in adolescents have not been investigated yet.

OBJECTIVES

To examine the associations of household cleaning agents use with the prevalence of asthma, rhinitis and eczema in adolescents.

METHODS

In this cross-sectional analysis, we included participants of the PIAMA birth cohort study with data on household use of 10 types of cleaning agents and information on asthma, rhinitis and/or eczema from parent-completed questionnaires at age 14 (N = 2333). For the cleaning agents, we developed a composite score ranging from 0 (no exposure) to 30 points (household use on 4-7 days per week for all 10 types of cleaning agents). Logistic regression was used to analyse associations between household cleaning agents use (composite score and specific cleaning agents) and outcomes, adjusting for potential confounders.

RESULTS

Seven, 13 and 11% of the participants had asthma, rhinitis and eczema, respectively, at age 14. The composite score for household use of cleaning agents was not associated with asthma, rhinitis and eczema. For instance, adjusted odds ratios (95% confidence interval) for the prevalence of asthma, rhinitis and eczema comparing those with the highest use of cleaning agents (≥10 points) to those with never/seldom use (0-4 points) were 0.95 (0.56, 1.63), 1.23 (0.82, 1.82) and 0.95 (0.56, 1.63), respectively. For individual cleaning agents, we only found the use of ammonia to be significantly associated with a lower risk of rhinitis [0.60, (0.44, 0.82)].

CONCLUSIONS

There was no indication of an increased prevalence of asthma, rhinitis or eczema among adolescents living in households within the highest category of cleaning agents use.

Indoor Sources of Air Pollutants

People spend an average of 90% of their time in indoor environments. There is a long list of indoor sources that can contribute to increased pollutant concentrations, some of them related to human activities (e.g. people's movement, cooking, cleaning, smoking), but also to surface chemistry reactions with human skin and building and furniture surfaces. The result of all these emissions is a heterogeneous cocktail of pollutants with varying degrees of toxicity, which makes indoor air quality a complex system. Good characterization of the sources that affect indoor air pollution levels is of major importance for quantifying (and reducing) the associated health risks. This chapter reviews some of the more significant indoor sources that can be found in the most common non-occupational indoor environments.