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This article examines electrochemical carbon monoxide (CO) sensors used as mobile devices by rescue and firefighting units in Poland. The conducted research indicates that the presence of chlorine (Cl 2 ), ammonia (NH 3 ), hydrogen sulfide (H 2 S), hydrogen chloride (HCl), hydrogen cyanide (HCN), nitrogen (IV) oxide (NO 2 ), and sulfur (IV) oxide (SO 2 ) in the atmosphere does not affect the functioning of the electrochemical CO sensor. In the case of this sensor, there was a significant cross effect in relation to hydrogen (H 2 ). It was found that the time and manner of using the sensor affects the behavior in relation to H 2 . Such a relationship was not recorded for CO. Measurements in a mixture of CO and H 2 confirm the effect of hydrogen on the changes taking place inside the sensor. Independently of the ratio of H 2 to CO, readings of CO were flawed. All analyses showed a significant difference between the electrochemical CO sensor readings and the expected values. Only in experiments with a 1:3 mixture of CO and H 2 was the relative error less than 15%. The relative error in the analyzed concentration range for a sensor with an additional compensation electrode ranged from 7% to 38%; for a sensor without this electrode, it ranged from 23% to 55%. It was ascertained that in the cases of measurements for tests carried out at higher concentrations of H 2 in relation to CO, a sensor with an additional electrode is significantly better (more accurate) than a sensor without such an electrode. Differences at the significance level p = 0.01 for measurements made in the CO:H 2 mixture at a ratio of 1:3 were ascertained.Sustainability 2020, 12, 14 2 of 11 membranes [2,9,10]. The electrodes can be made of various materials. Many kinds of nanoparticles, such as metal, oxide, and semiconductor nanoparticles, have been used for constructing electrochemical sensors [11][12][13][14][15].The electrochemical sensor market is expected to register a Compound Annual Growth Rate of 11.4% over the forecast period 2019-2024. The emergence of nanotechnology-based sensors will drive the market during the forecast period [16].Statistical data indicate that the most common reason for the intervention of emergency services is the suspected release of carbon monoxide. CO is formed as a result of incomplete combustion of carbon and organic substances. As CO is an odorless, tasteless, and colorless gas, it is known as the silent killer. CO poisoning is the most common type of deadly air poisoning in many countries [17]. CO enters the body mainly through the respiratory system, and the amount that enters the body depends on the concentration of CO in the air and the amount of time for which a person breathes polluted air. The most common symptoms include headache, nausea and vomiting, dizziness, lethargy, and a feeling of weakness [18,19]. Health effects associated with exposure to CO range from the more subtle cardiovascular and neurobehavioral effects at low concentrations to unconsciousness and death after acute or chronic exposure to...

Nevertheless, meteorological and terrain conditions have a big impact on the measurement results. During measurements, the detector indicated the presence of other substances. Moreover, it was found that under cloudy and windy weather, remote detection is not possible.

This study assessed inhalation exposure to particulate matter (PM1)-bound mercury (Hgp) and PM1-bound polycyclic aromatic hydrocarbons (PAHs) among university students. For this purpose, simultaneous indoor (I) and outdoor (O) measurements were taken from two Polish technical universities (in Gliwice and Warsaw) located in distinct areas with respect to ambient concentrations and major sources of PM. The indoor geometric mean concentrations of Hgp were found to be 1.46 pg·m−3 and 6.38 pg·m−3 in Warsaw and Gliwice, while the corresponding outdoor concentrations were slightly lower at 1.38 pg·m−3 and 3.03 pg·m−3, respectively. A distinct pattern was found with respect to PAH concentrations with estimated I/O values of 22.2 ng·m−3/22.5 ng·m−3 in Gliwice and 10.9 ng·m−3/11.12 ng·m−3 in Warsaw. Hazard quotients (HQs) as a result of exposure to Hgp for students aged 21 ranged from 3.47 × 10−5 (Warsaw) to 1.3 × 10−4 (Gliwice) in terms of reasonable maximum exposure (RME). The non-cancer human health risk value related to Hgp exposure was thus found to be below the acceptable risk level value of 1.0 given by the US EPA. Daily exposure values for lecture hall occupants, adjusted to the benzo(a)pyrene (BaP) toxicity equivalent (BaPeq), were 2.9 and 1.02 ng·m−3 for the Gliwice and Warsaw students, respectively. The incremental lifetime cancer risk (ILCR) values with respect to exposure to PM1-bound PAHs during the students’ time of study were 5.49 × 10−8 (Warsaw) and 1.43 × 10−7 (Gliwice). Thus, students’ exposure to indoor PAHs does not lead to increased risk of lung cancer.

Vitamin D supplementation in patients with urolithiasis and hypercalciuria is considered to be unsafe. We analyzed the impact of vitamin D supplementation on selected health status parameters in children with idiopathic hypercalciuria. The study included 36 children with urolithiasis resulting from excessive calcium excretion. The level of calcium and 25(OH)D (hydroxylated vitamin D - calcidiol) in serum, urinary calcium excretion and the presence of stones in urinary tract were assessed prospectively. Blood and urine samples were collected at the time when the patient was qualified for the study and every three months up to 24 month of vitamin D intake at a dose of 400 or 800 IU/day. At time zero and at 12, and 24 months of vitamin D supplementation, densitometry was performed. Supplementation with vitamin D caused a statistically significant increase in the concentration of 25(OH)D in serum. There were no significant changes in calcium concentration in serum, excretion of calcium in urine but also in bone density. There was no significant increase in the risk of formation or development of stones in the urinary tract. Supplementation with vitamin D (400–800 IU/day) in children with idiopathic hypercalciuria significantly increases 25(OH)D concentration, does not affect calciuria, but also does not improve bone density.