An evaluation of childhood carbon monoxide intoxications in a rural area using the Beaufort wind scale

Climatic changes are known to affect CO intoxications. The purpose of this study was to examine childhood CO intoxications with the Beaufort wind scale (BWS) classification of wind speeds. The demographic data (age and sex) and information concerning the hour, day, and month of presentation to the emergency department for cases diagnosed with CO intoxication over a 7-year period between 2015 and 2021 in the pediatric emergency department of a tertiary training and research hospital in a rural area were examined. Wind speeds (m/s) measured on the days of presentation to the emergency department were recorded. The wind category on the BWS on the day of intoxication was then determined. Four hundred twenty-two patients, with a mean age of 95.12 ± 59.4 (1–215) months, 218 (51.7%) girls and 204 (48.3%) boys were diagnosed with CO intoxication over the 7-year study period. A comparison of wind speeds on the days of presentation to hospital revealed a significantly higher wind speed in 2020 than in the other years (p<0.001). A comparison of the groups in terms of the BWS revealed a significant difference between the years of presentation to hospital (p:0.001). This is the first study to investigate CO intoxications in the pediatric emergency department with the BWS. A significant association was observed between wind speed based on the BWS and childhood CO intoxications. Further studies evaluating wind in the rural setting and CO intoxications are now needed for protection against such intoxications.


Introduction
Carbon monoxide (CO) is a colorless, odorless, and tasteless toxic gas resulting from incomplete combustion of hydrocarbons and causing morbidity and mortality when inhaled.CO gas exhibits 240-fold greater affinity for hemoglobin in erythrocytes compared to oxygen (Reumuth et al., 2019).As a result of CO inhalation, the oxygen required by the body cannot be delivered to tissues.CO also compromises cardiac output by binding to myoglobin.Studies at the cellular level have shown that CO causes an increase in lipid peroxidation, loss of function at the mitochondrial level, an increase in oxygen radicals as a result of activation in neutrophils and lymphocytes, oxidative stress, apoptosis and reperfusion injury, and tissue damage throughout the body (Eichhorn et al., 2018).CO emitted from stoves burning solid fuels (such as wood and coal) for heating and hot water, inappropriate waste gas extraction systems (chimneys), gas heaters, boilers, and catalytic stoves can result in intoxication (Tursun et al., 2017).Cases of intoxication caused by CO-producing generators due to prolonged electricity cuts were reported following a hurricane in the USA in 2018 (Henretig et al., 2018).Various meteorological events and data have previously been shown to affect the occurrence of CO intoxication (Du et al., 2010;Yılmaz et al., 2020).The Beaufort wind scale (BWS) is a system in which winds are classified from 0 to 12 depending on their speed, and that dates back approximately 200 years (Wheeler & Wilkinson, 2004).
Information concerning the weather is recorded for cities on a daily, monthly, and yearly basis, and forecasting systems are also capable of predicting weather in advance.The purpose of this study was to investigate the association between childhood CO intoxications in a rural area and the BWS.

Material and methods
The hospital records of cases presenting to a tertiary training and research hospital pediatric emergency department in 2015-2021 and diagnosed with CO intoxication were examined retrospectively.The city of Adıyaman, where the study was performed, has a population of 632,000, stands 669 m above sea level at 37° 48′ 2″ N, 38° 18′ 19″ E in the southeast of Turkey, and has a continental climate (Adiyaman.gov.tr, 2022).
Age (months), gender (female, male), the year, month, and day of presentation, and the time of presentation (08.00-16.00,16.00-24.00,or 00.00-08.00)were recorded from the patient records.The daily wind speed (m/s) during the study period was determined from meteorological records for previous years (1 meter per second = 3.6 kilometers per hour = 1.945 knots).BWS classification was performed based on the mean wind speed for the days on which the patients presented to the hospital (Table 1).The groups were then compared on the basis of the data obtained.Cases involving exposure to CO due to fires or due to successful or attempted suicide were excluded.Approval for the study was granted by the local ethical committee (no: 2022/3-23).In this retrospective study, informed consent was not needed.
The data obtained in the study were analyzed on SPSS (IBM, version 21.0, Chicago, IL, USA) software.Categorical data were expressed as numbers (%) and were compared using the chi-square test.Levene's test of homogeneity of variance was applied.Parameters with non-homogeneously distributed variances were analyzed using the Welch test, and those with homogeneously distributed variables using the  19%).Examination of time intervals showed that presentations to hospital were most frequent at 00.00-08.00h (47.9%).Statistically significant differences were observed between the study years in terms of months, days of the week, and times of presentation (p:0.001 for all) to the pediatric emergency department.The general study data are shown in Table 2.
A comparison of mean wind speeds on the days when cases presented to the hospital revealed a significantly higher speed in 2020 than in the other years (p<0.001).Evaluation of wind speeds based on Games-Howell test results showed no significant difference between 2020 and 2019 (p:0.722) or 2021 (p:0.988), while significant differences were found between 2020 and the other years (p:0.001).Significant variation in terms of BWS was also determined among the years (p:0.001).Data concerning wind speed and BWS for the years of presentation are shown in Table 3.

Discussion
Due to its colorless and odorless nature, CO is known as the "silent killer" (Can et al., 2019).According to data from the USA, unintentional, non-fire-related CO intoxication is responsible for an annual 20,000 emergency presentations, 2000 hospitalizations, and 450 deaths (Iqbal et al., 2012).Studies investigating the source of environmental CO accumulation have implicated inadequate ventilation systems, machinery emitting CO in closed environment in production facilities, the use of coal-burning stoves, gas-burning stoves, and gas-based water heaters (Bekkedal et al., 2006;Bleecker, 2015).The frequency of CO intoxications has been proved to decrease with the use of CO detectors, with milder clinical findings being observed due to early warnings when CO intoxication occurs in areas equipped with such devices (Christensen et al., 2020).However, the use of CO detectors in homes in developing countries is not practicable for economic reasons.Studies have shown that the frequency of CO intoxications differs between rural and urban areas (Roca-Barceló et al., 2020).The incidence of CO intoxication is known to be higher in winter (Al-Matrouk et al., 2021).It should not be forgotten that the risk factors for CO intoxication listed above also include meteorological events and changes.
In a study from 1989, Gijsenbergh et al. ( 1989) reported a link between emergency department presentations and meteorological data, and that a high wind speed plays a role in CO intoxications due to gas boilers, while vertical/horizontal air movement plays a role in CO intoxications resulting from coal stoves.In a study from the Turkish capital, Ankara, Yılmaz et al. (2020) described that there is a relationship between wind direction/speed and the source causing CO poisoning (blaze and geyser).A study investigating climatic factors and CO intoxications in Beijing reported an inverse correlation between temperature and intoxications, but determined no association with barometric pressure, visibility, humidity, or wind speed (Du et al., 2010).Ruan et al. (2021) revealed an association between low wind speed and CO intoxication.In a study from Taiwan, the authors reported no link between wind speed and CO intoxications, but stated that accidental CO intoxications occur in indoor areas associated with coal-burning stoves or heating systems, thus accounting for the lack of effect of outside wind (Wang et al., 2021).A study of environmental pollution in the Romanian city of Timisoara revealed that CO emissions from vehicle exhausts were directly associated with temperature and humidity, and inversely correlated with wind speed (Barbulescu & Barbes, 2017).The authors of a study from the metropolitan region of Sao Paulo in Brazil reported that CO concentrations increased in case of wind speeds lower than 1.3 m/s (Rozante et al., 2017).The source of CO in the studies from both Romania and Sao Paulo was vehicular traffic, and both investigated environmental pollution.

Table 1
Beaufort wind scale classifications BWS Beaufort wind scale, m meter, mph mile per hour, sec second However, CO intoxications are more common in enclosed areas, in case of poor ventilations systems and coal or wood-burning stoves being used for heating.Populations living in rural areas in developing countries require new, simple, and practical early warning methods for protection against CO intoxications.The findings of the present study reveal an association between BWS and CO intoxication in a rural area.This study is the first to evaluate childhood CO intoxications with the BWS.It indicates that the rural population can be warned about possible CO intoxications, preventable events, by local officials if a high wind speed on the BWS is predicted.