Reduced Carbon Monoxide Levels Research Articles

Indoor Air Quality in Laboratories and Its Relationship with Psychological Performance Among University Students in Malaysia

Introduction: Poor indoor air quality (IAQ) in work environments can reduce productivity and decrease overall performance. This study examines IAQ in university laboratories and its relationship with psychological performance among students in Malaysia. Methods: This cross-sectional study was conducted from October to November 2023 in six laboratories at a Malaysian university, categorised into chemical and non-chemical. A total of 117 students aged 18 to 40 participated. IAQ was measured in real-time for 8 hours during weekdays using instruments for particulate matter (PM2.5, PM10), carbon monoxide (CO), total volatile organic compounds (TVOC), airborne microorganisms, carbon dioxide (CO2), temperature in °C, relative humidity (RH), and air movement. Psychological performance was assessed using the General Health Questionnaire (GHQ-12) and Post Occupancy Evaluation (POE). Data analysis was performed using Kruskal-Wallis, One-Way ANOVA, and Chi-Square tests. Results and Discussion: Significant differences in IAQ parameters were observed for PM2.5 (p=0.007), PM10 (p=0.020), CO2 (p=0.024) and RH (p=0.043). Psychological distress affected 41.9% of students based on the predefined threshold. High CO levels (≥0.67 ppm) and elevated temperatures (≥23.28°C) were significantly associated with increased psychological distress (p=0.011). Students exposed to these conditions were 1.3 times more likely to experience distress (OR=1.3). Conclusion: Specific IAQ parameters, particularly CO and temperature, critically impact students’ psychological well-being. Improving IAQ by reducing CO levels and maintaining optimal temperatures may enhance mental health and performance. Improving IAQ by reducing CO levels and maintaining optimal temperatures may enhance mental health and performance. However, external factors such as personal stressors could not be entirely controlled.

Effectiveness of Text Messaging in Encouraging Smoking Cessation among Non-Communicable Disease Patients: A Randomized Controlled Trial.

To assess the impact of a text-messaging intervention on smoking cessation among patients with non-communicable diseases. A total of 200 participants were randomly assigned to either a text-messaging intervention group or a control group. The 7-day point prevalence of smoking cessation and exhaled carbon monoxide (CO) levels were measured at baseline, 6 weeks, and 18 weeks. Mixed linear regression was employed to examine the interaction effect of exhaled CO between the intervention group and follow-up time. The 7-day point prevalence of smoking cessation increased by 16.16% (95% CI: 10.98, 21.33) at the 6-week follow-up and by 15.46% (95% CI: 10.68, 21.33) at the 18-week follow-up. In the intervention group, exhaled CO was significantly lower compared to the control group at 6 weeks (mean difference: -5.79; 95% CI: -7.26, -4.32) and at 18 weeks (mean difference: -4.19; 95% CI: -5.67, -2.71). The text-messaging intervention proved effective in increasing the prevalence of smoking cessation and reducing carbon monoxide levels among non-communicable disease patients.

Optimization Design of Reducting Co & HC Gas through Alloy Converter Catalyst Prototype Model

Technological developments have an impact on increasing the number of motorized vehicles such as motorcycles, cars, and other modes of transportation. This causes air pollution impacts such as gas emissions from fossil fuels. Substances from hazardous exhaust gases consist of carbon monoxide (CO), carbon dioxide (CO2), nitrogen oxides (NO or NOx), and hydrocarbons (HC). Therefore, the purpose of this research is to design a catalytic converter through a mixture of several metals obtained from various wastes in Small and Medium Enterprises. A mixture of copper, brass, aluminium and zinc to be created as a muffler or exhaust on the test vehicle, namely the 2005 Car. The observed exhaust emissions are CO & HC using a Gas Analyzer. Measurements were observed at vehicle rotation of 1000 rpm, 2000 rpm, 3000 rpm, 4000 rpm and 5000 rpm. The results showed that the highest proportion of reduced CO levels was the use of a catalyst at 2000 rpm engine speed, which was 5.23 with Pertamax fuel, while petrolite fuel using a catalyst with 2000 rpm engine speed was 5.5. The highest percentage reduction in HC levels was when using a catalyst with engine speed of 1000 rpm of 645% with Pertamax fuel, while for pertalite fuel using a catalyst with engine speed of 1000 rpm was 705.5%

Hubungan Umur, Intensitas Merokok, Status Gizi, Lili Paris (Chlorophytum Comosum) Terhadap Kadar CO Asap Rokok Dan COHb Dalam Darah

Polluted air especially indoors can cause serious problems compared to outdoors. One of the most common pollutants found indoors is carbon monoxide (CO). CO that binds to blood will form carboxyhemoglobin (COHb) bonds, the main source of CO in a closed room comes from cigarette smoke. CO levels that will enter the body are greater in smokers than non-smokers, paris lilies can reduce CO levels. The purpose of this study was to determine the relationship between age, smoking intensity, nutritional status, CO in indoor cigarette smoke and COHb. This research method is quantitative, room CO is measured at 3 sampling points 2 times and blood collection is carried out 2 times as much as 0.05 ml. Respondents in this study were 7 men aged 33-50 years. Yield of CO 4 ppm. COHb has a decreasing value of 0.717%. The value of simple linear regression analysis of the relationship between smoking intensity and COHb with the addition of 5 paris lilies R2 = 0.6379 means that it has a moderate relationship.Keywords: COHb, age, smoking intensity, nutritional status, indoor cigarette smoke CO

The Effect of Installing Modified Copper in Muffler to Reduce CO Levels in Vehicle Exhaust

This study aims to determine the effectiveness of modified copper to reduce carbon monoxide (CO) levels. Copper in the form of a plate shaped like a honeycomb and altered with activated carbon (SiO) and ZSM-5. The test uses a four-stroke 125 CC two-wheeled motor vehicle, fuel using Petalite, gasohol E5, gasohol E10, gasohol E15. The test carried out is the emission test of the effect of fuel variations and modified copper. The use of petalite fuel, variations of honeycomb copper + activated carbon (SiO-C) + ZSM-5 is more effective because it can reduce CO levels the most, which is 3.66% CO at 9000 rpm engine speed. For E5 fuel, the use of a honeycomb-shaped copper exhaust + Titan dioxide (TiO2) + Activated carbon (SiO-C) + ZSM-5 reduces CO levels by 3.42% CO at 9000 rpm engine speed. On the other hand, E10 fuel reduces CO levels by 1.35% CO when using exhaust with honeycomb copper+ TiO2 + SiO-C +ZSM-5.

Evaluation of carbon monoxide emissions of electric power generators used in buildings in Ibadan Metropolis, Nigeria


 
 
 
 Abstract: Poor supply of electricity to different settlements over the years in Nigeria has forced building occupants to shift to dependence on generators. This study thus determined outdoor and indoor carbon monoxide levels of generators used in both residential and commercial buildings and assessed its impact on the users and the environment. The study was carried out in Ibadan Metropolis, Nigeria, which was divided into core, transition and suburban zone respectively. Five (5) residential and commercial buildings respectively were purposively selected in each of the zones of the study area. The HT- 1000 digital LCD carbon monoxide meter was used to take measurements of the emissions of carbon monoxide with conformity to NESREA AND OSHA standards. The outdoor emission levels of the carbon monoxide before or during the use of generators were taken at 0, 2 and 4 m respectively from the external walls of the buildings sampled and the corresponding indoor measurements were taken internally at 1.2-1.5m above floor area. The data collected were analysed with the use of statistical methods such as t-test, trend analysis and Kolmogorov smirnov test. The results showed that outdoor and indoor measurements of carbon monoxide emissions levels were highest in buildings in the core zone either before or during the use of generating sets. Reduced carbon monoxide levels during use of generators were obtained at distance limits beyond 2 m from external walls of buildings across zones of the study area. In view of the measurements taken, being above limits set by statutory bodies, during use of generators, and its attendant effects on the environment and building occupants, it was recommended that its users should be enforced to position them in enclosures located away from external walls of buildings and government should license only sales of generating sets with emission control mechanisms.
 
 
 

Study of the impact of operation distance of outdoor portable generators under different weather conditions

The US Centres for Disease Control and Prevention has reported that up to half of non-fatal carbon monoxide (CO) poisoning incidents during the hurricane seasons in 2004 and 2005 involved generators operated outdoors but within 7 ft of the home. Current guidance for safe operating distances of generators is often neither specific nor consistent. A study was conducted to examine the impact of generator distance on indoor CO exposure. The study was based on computer simulations of CO transport outdoors and subsequently into a generic two-storey house. This paper presents the simulation results when using an indoor air quality model coupled with a computational fluid dynamics model to predict CO concentrations near and within the home. Fire Dynamics Simulator was validated against the measured contaminant dispersion data in a wind tunnel. A parametric study was then conducted for the two-storey house to consider the effects on indoor CO levels of generator location, distance, exhaust temperature and speed and weather conditions. It was found that in most cases, to reduce CO levels for the conditions modelled, it was more effective to point the generator exhaust away from the house and position the generator at a distance of >4.6 m.

Experimentally‐Induced Spontaneous Opiate Withdrawal: Relationship to Cigarette Craving and Expired Air Carbon Monoxide

Smoking often increases after opioid use among those addicted to both opioids and nicotine, but the relationship between smoking and experimentally induced spontaneous opioid withdrawal (OW) has not been characterized. Six inpatient opioid-dependent smokers were stabilized on morphine 15 mg SC QID. Expired air carbon monoxide levels and smoking craving were measured for each participant on ten days when spontaneous OW was experimentally induced and on ten separate days in the absence of OW. Spontaneous OW was associated with significantly reduced carbon monoxide levels and smoking craving. Interestingly, craving was only reduced for items related to the positive reinforcing effects of smoking. These preliminary results suggest that OW may be a favorable context to initiate smoking cessation treatment interventions.

Effectiveness of Payment for Reduced Carbon Monoxide Levels and Noncontingent Payments on Smoking Behaviors in Cocaine-Abusing Outpatients Wearing Nicotine or Placebo Patches.

In a 2-week intervention to reduce cigarette smoking among outpatients in treatment for cocaine addiction, 20 subjects were randomly assigned to a contingent group, receiving monetary vouchers for breath samples with carbon monoxide (CO) levels of 8 ppm or less, or to a noncontingent group, receiving vouchers regardless of CO level. Subjects wore either nicotine or placebo patches in a randomized crossover design. Contingent subjects had significantly lower CO levels and met the 8 ppm target significantly more often than did noncontingent subjects; however, number of cigarettes reported smoked did not differ between groups. Use of nicotine patches resulted in CO levels significantly lower than did use of placebo patches, but levels still exceeded 8 ppm regardless of type of patch. Because contingent reward helped cocaine-dependent smokers achieve nonsmoking CO targets, behavioral antismoking interventions merit continued study in similar populations.

A placebo controlled trial of bupropion for smoking cessation in schizophrenia

Background: Schizophrenic patients have high rates of cigarette smoking compared with the general population. We compared sustained-release (SR) bupropion with placebo for smoking cessation in patients with schizophrenic disorders. We also examined how antipsychotic class predicts smoking cessation outcomes with bupropion. Methods: Thirty-two subjects meeting DSM-IV criteria for schizophrenia or schizoaffective disorder and nicotine dependence were randomized to bupropion SR (BUP, 300 mg/day) or placebo (PLA). Outcomes included treatment retention, smoking abstinence rates, expired breath carbon monoxide (CO) levels, psychotic symptoms, and medication side effects. Results: Bupropion significantly increased trial endpoint 7-day point prevalence smoking abstinence rates compared with placebo [BUP, 8/16 (50.0%), PLA, 2/16 (12.5%); χ 2 = 5.24, df = 1, p < .05], and reduced CO levels during the trial [Medication × Time interaction; Z = 3.09, p < .01]. Positive schizophrenia symptoms were not altered by BUP, but negative symptoms were significantly reduced. Atypical antipsychotic drug treatment enhanced smoking cessation responses to BUP. Major side effects were dry mouth, gastrointestinal symptoms, headache, and insomnia. Conclusions: Our results suggest that 1) BUP enhances smoking abstinence rates compared with PLA in nicotine-dependent schizophrenic smokers; 2) BUP is well-tolerated and safe for use in these patients; and 3) atypical antipsychotics may enhance smoking cessation outcomes with BUP.

Quantitative investigation of catalytic natural gas conversion for hydrogen fuel cell applications

Hydrogen generation from natural gas for driving proton exchange membrane fuel cells in residential small-scale combined heat and power (CHP) applications is investigated by a series of computer simulations. Natural gas is converted into hydrogen either by the combined oxidation–steam reforming, i.e. indirect partial oxidation mechanism on Pt-Ni catalyst or by the direct, one-step partial oxidation mechanism on Pt monoliths. A water–gas shift converter and a catalytic selective carbon monoxide oxidation unit are used for reducing carbon monoxide levels to a value which the anode of proton exchange membrane fuel cell (PEMFC) can tolerate. Unconverted hydrocarbons and hydrogen rejected from the fuel cell are considered to be oxidized in a Pt catalyst packed afterburner in order to supply energy to the system. Reactor simulations based on available kinetic data together with energy integration calculations indicate direct partial oxidation to give higher hydrogen yields corresponding to increased electrical power outputs and elevated efficiencies. Indirect partial oxidation has the advantage of operating simplicity, since the direct route runs only at millisecond level residence times and high temperatures. In both mechanisms, water injection and energy integration are critical issues in adjusting product yields and in temperature control. The simulation outputs are compared and validated by the results based on the thermodynamics of the pertinent mechanism.

MTBE: The Headache of Cleaner Air

Gasoline with methyl tertiary butyl ether (MTBE) has been sold in the United States since 1979, when it was added to fuels as an octane enhancer after lead was phased out of motor fuels. Recently it has been introduced as a means of reducing carbon monoxide emissions during the winter months in targeted US cities. However, there is concern over health complaints including headaches, dizziness and nausea from residents of some areas. These reports have launched an era of assidious research by scientists and public health officials across the country to learn more about MTBE`s short-term and long-term, and possibly carcinogenic, health effects. New research should help weigh the risk of MTBE as a possible carcinogen and the effectiveness of MTBE-blended fuels in reducing carbon monoxide levels. The question is whether, in minimizing one risk, is another risk - however small - being introduced?

Contingent reinforcement for reduced carbon monoxide levels in methadone maintenance patients

Five cigarette smoking methadone maintenance patients (MMP) participated in a within-subjects (A-B-A-B) study involving repeated application of carbon monoxide (CO)-contingent payments for reductions in smoke intake. To replicate and extend findings from an earlier study in non-drug-abusing smokers (Stitzer & Bigelow, 1982), we used the same contingent reinforcement procedure that involved the delivery of a monetary payment ($5) for CO readings which were 50% or less than the average value of readings obtained during the prior noncontingency period. Although four of the five subjects earned the contingent payment on at least three of the eight occasions, the overall effect of the intervention on CO level was nonsignificant. Daily smoking records revealed significantly lower rates during the first contingency intervention for the group as a whole. Significant correlations between CO and the time interval since smoking prior to CO measurement were found. The rather modest intervention effects suggest that important parameters be considered when designing contingency management procedures to reduce cigarette smoking in this difficult population of drug abusers.

Carbon monoxide budget in the northern hemisphere

To improve urban air quality the major industrialized nations of the West took steps during the 1970s and 1980s to reduce carbon monoxide (CO) emissions from automobiles and other industrial sources. Overall, CO/CO2 emission ratios from the mix of fossil fuel combustion sources have been reduced by about half during 1976–1990. Also, the tropospheric abundance of hydroxyl radical (OH), which is the main sink for CO, is proposed to have increased globally by about 1.0±0.8% yr−1 [Prinn et al., 1992]. We use a simple two‐box model to examine the impact of shrinking emissions and increasing OH on the global abundance of CO. We find that these factors contribute about equally in reducing CO levels in the Northern Hemisphere troposphere by about 1.8±0.8 ppb yr−1 on average.

Estimation of Respiratory Irritancy from Inhaled Methyl Tertiary Butyl Ether in Mice

The Clean Air Act Amendments require the use of oxygenated fuels in the winter months to reduce carbon monoxide levels in areas of the country that exceed national health standards for carbon monoxide. Methyl tertiary butyl ether (MTBE, CAS number 1634–04–4) is the most widely used fuel additive for this purpose. During implementation, people in a few areas of the country reported nose, eye, and throat irritation. Jo evaluate the potential for MTBE to produce symptoms indicative of sensory irritation, mice were tested using a standard bioassay. Concentration-response data obtained from 1-h exposures to MTBE between 300 and 30,000 mglm3 revealed that slight to severe sensory irritation occurred with exposure to all concentrations. At the highest concentration both sensory and pulmonary irritation was observed, indicative of acute lung injury. However, lung lavage protein and lactate deliydrogenase measurements did not support this contention. Respiratory rate was predicted by linear interpolation to be decreased by 50% (RD50) at 16,600 mg/m3 MTBE. Some experts suggest that 3% of the RD50 (in this case 500 mg/m3) would not cause significant sensory (i.e., discomforting) irritation. Since this estimate is at least an order of magnitude greater than typical peak atmospheric exposure levels during refueling, the data would suggest that few healthy individuals would experience sensory irritation during transient exposures to MTBE.

Clinical evaluation of a citric acid inhaler for smoking cessation

In this study, we evaluated the efficacy of a hand-held inhaler as an adjunct to a smoking cessation behavioral program. The inhaler delivered a citric acid aerosol with tobacco smoke flavor. Seventy-four smokers were recruited for a 3-week smoking cessation trial. During the first 12 days of the cessation period, smokers used the citric acid aerosol inhaler instead of a cigarette whenever the urge to smoke occurred. The citric acid inhaler significantly reduced CO levels and enhanced rates of smoking abstinence for those with higher than average (34.2 ppm) baseline end-expired carbon monoxide (CO) levels. Craving for cigarettes and negative affect were also alleviated by the citric acid aerosol. These results suggest that the citric acid aerosol may promote successful smoking reduction or cessation in a subgroup of smokers and relieves withdrawal symptoms such as craving for cigarettes, a symptom difficult to treat with currently available nicotine replacement techniques.

Carbon monoxide assessment of smoking in chronic obstructive pulmonary disease

Chronic Obstructive Pulmonary Disease (COPD) is a major, often fatal, drain on health-care resources. Most cases of COPD result from Tobacco Dependence, and smoking cessation slows COPD's progression. But there is very little information on treating Tobacco Dependence in COPD patients. In preparation for clinical trials using monetary payments to motivate reduced smoking, as assessed by breath carbon monoxide (CO) levels in COPD patients, we have addressed three issues. First, surveying 182 advanced COPD patients, we found that CO levels above 8 parts per million (ppm) were strongly associated with a self-report of current smoking, and that CO levels correlated neither with COPD severity, nor with age; about one-third of these patients were currently smoking. Second, among 12 still-smoking COPD patients serially observed for 8 h, CO half-life averaged about 6.5 h. Third, 8 patients reinforced with lottery tickets for CO reductions significantly reduced CO levels during 2 test weeks, mainly by deferring smoking before scheduled CO measurements.

The Seattle Automobile Inspection and Maintenance Program

The state of Washington instituted an automobile emissions testing and maintenance program in the Seattle-Bellevue area in 1982, the purpose of which is to reduce carbon monoxide levels to meet the federal standards. This study measures the impact of the program at two air quality monitoring stations in Seattle, comparing these stations to one in Tacoma. Six separate analyses of the program's effect on carbon monoxide are presented that differ by location, time period, and statistical method used. None of the six shows a significant program impact. The conclusion is that the possibility of a significant decline in carbon monoxide due to the testing program is remote.

Contingent reinforcement for reduced carbon monoxide levels in cigarette smokers.

Expired air carbon monoxide (CO) was evaluated simultaneously as the target for a contingent reinforcement intervention to promote smoking reduction and as a measure of within-subject changes in recent smoking rates and patterns. Eleven volunteer smokers participated in a three-week study which utilized an A-B-A design. CO levels were measured on weekday afternoons between 3:00 and 4:30 p.m. and detailed self-report records of smoking were kept by subjects throughout the study. A monetary payment of +5.00 was available during study week 2 for CO readings which were 50% or less of the average reading obtained for that subject during study week 1. Contingent payment was withdrawn during study week 3. Three measures of smoking changed in an orderly manner during the study. CO readings were reduced from initial baseline levels during study week 2 but generally did not return to original baseline levels when the contingency was withdrawn. Number of daytime cigarettes recorded decreased and minutes of cigarette abstinence prior to the afternoon study contact increased during the contingent intervention period compared to baseline study phases. The average within-subject correlation between expired air CO level and number of daytime cigarettes was 0.67 (p less than 0.01), that between CO and time since last cigarette was -0.59 (p less than 0.05). Expired air CO appears to be an appropriate target for contingent reinforcement intervention as well as an objective measure which reflects rates and patterns of recent smoking in individual subjects.

Methods to reduce carbon monoxide levels at the workplace

Cardiovascular disease and death attributed to the workplace exposure to carbon monoxide (CO) can be reduced. It is possible to control the removal of CO through existing engineering principles and techniques. However, it is desirable that the methods that reduce the formation of CO and prevent its introduction into the workplace be developed and utilized. Perhaps the greatest long-term tragedy of today's standard is that future plants, which often can meet more stringent standards, are not required nor have the incentive to do so under existing Federal policies. There is a need to develop a “new source performance standard” concept as part of the implementation of the Occupational Safety and Health Act. The greatest potential to eliminate future occupational health problems rests with the opportunity to encourage new plant designs that would reduce worker exposure, thus greatly eliminating future problems. The concept of new source performance standards has existed in the control of general environmental pollution in the ambient air and in water. It is generally recognized that control of emissions from new and future plants is usually easier than control of emissions from existing older plants. What does not seem to be understood is that control of emissions in the workplace will frequently prevent general environmental contamination as well. The problem is prevented at the source. The opportunity to prevent hazardous exposure to CO exists. It must be taken by those who have a knowledge of CO, and shared with professionals, management, and employees if there really is to be a reduction of CO levels at the working place. The benefits are not only the safety and health of employees, but the conservation of energy and materials, the creation of new products and new economic opportunities, etc. This pyramiding of benefits can be the result of achieving methods to reduce CO levels at the working place.