Volatile organic compounds: A threat to the environment and health hazards to living organisms - A review

Association between exposure to volatile organic compounds and female infertility: An NHANES analysis

OBJECTIVE

Infertility affects a large portion of the global population, with environmental, lifestyle, and biological factors contributing to its incidence. Volatile organic compounds (VOCs) are widely used in consumer products, and are considered environmental pollutants and are associated with various adverse health outcomes. However, their impact on female fertility remains unclear. This study investigated the relation between urinary VOC metabolite levels and infertility in women.

MATERIALS AND METHODS

This cross-sectional analysis utilized data from the National Health and Nutrition Examination Survey (NHANES) for the years 2013-2018. Female participants 18-45 years old with reproductive health data were included. Infertility status was determined through questionnaire responses, and urinary VOC metabolite levels were obtained from the NHANES laboratory data. The associations between VOC levels and infertility were assessed through univariate and multivariable regression analyses.

RESULTS

Of the 29,400 female participants in the NHANES data set, 1097 women met the inclusion criteria. Multivariable analysis adjusted for confounders showed significant associations between 12 specific VOC metabolites and an increased likelihood of infertility, with N-Acetyl-S-(3,4-dihydroxybutyl)-l-cysteine (DHBMA) (adjusted odds ratio [aOR] = 1.48, 95 % confidence interval [CI]: 1.04-2.12, p = 0.030) and N-Acetyl-S-(2-hydroxypropyl)-l-cysteine (2HPMA) (aOR = 1.41, 95 % CI:1.07-1.85, p = 0.016) showing the strongest associations.

CONCLUSIONS

Our study highlights a significant association between specific urinary VOC metabolites and an increased likelihood of infertility in women. While causality cannot be conclusively determined, the findings offer an initial insight into the reproductive health risks linked to VOC exposure.

Using Green Solvents for Phase Inversion of PVDF/TiO2 Hybrid Coatings for Gas Phase Photocatalysis

Long-time exposure to volatile organic compounds (VOCs) in the atmosphere can have negative health effects on humans and other living organisms. In order to purify ambient air, these VOCs can be degraded using photocatalysis. In this research, commercially available TiO2 nanoparticles were immobilized in a porous poly(vinylidene fluoride-co-hexa-fluoropropylene) (PVDF) polymer matrix, synthesized using the phase inversion method. The most used solvent for PVDF is N-methyl-2-pyrrolidone (NMP). However, this solvent is known to be harmful to humans and the environment, and there is a need to replace NMP with a more ecological 'green' solvent. Here, triethyl phosphate (TEP), methyl-5-(dimethylamino)-2-methyl-5-oxopentanoate (Rhodiasolv® PolarClean) and propylene carbonate (PC) were used to dissolve PVDF for the phase inversion synthesis of porous photocatalytically active PVDF/TiO2 hybrid layers onto aluminium slides. The photocatalytic degradation under UV (365 nm) of gaseous ethanol in an argon/oxygen (Ar/O2) atmosphere shows that these solvents are suitable replacements for NMP, but optimization is required to improve the performance of the layers. Apart from changing the solvent for PVDF, the UV and photocatalysis stability of PVDF has been determined, as well as the repeatability of the photocatalytic reaction, to prove that PVDF is a suitable polymer for this application.

Harnessing Electrostatic Forces: A Review of Bees as Bioindicators for Particulate Matter Detection

Bees (Hymenoptera, Anthophila) are widely recognized for their essential ecological roles, including pollination and biodiversity maintenance. Recently, their ability to collect environmental particulate matter through electrostatic forces has been explored for biomonitoring purposes. This review integrates knowledge on electrostatic pollen adhesion with emerging insights into particulate matter adhesion to bees, emphasizing their potential as bioindicators. The mechanisms of electrostatic adhesion, influenced by factors such as the physicochemical properties of particulate matter and bee morphology, are discussed in detail. Additionally, the study evaluates the adhesion efficiency of pollutants, including heavy metals, microplastics, nanoplastics, pathogens, pesticides, radionuclides, and volatile organic compounds. This multidisciplinary approach underscores the role of bees in advancing environmental monitoring methodologies and offers innovative tools for assessing ecosystem health while addressing the drivers of bee decline.

WO3/Ru@CeO2 Bilayer Gas Sensor for ppb-Level Xylene Detection Based on a Catalytic-Sensitive Synergistic Mechanism

Volatile aromatic hydrocarbons present a significant threat to both the environment and human health. However, due to the low reactivity of toxic gases containing benzene rings and insufficient selectivity of existing sensors, real-time monitoring of benzene series (BTEX) gases remains a challenge. The development of catalytically sensitive synergistic bilayer sensors offers a promising strategy to overcome this challenge. A series of Ru@CeO2 nanosheets with different Ru doping levels were synthesized by using a simple solvothermal and further calcination method. Interestingly, the incorporation of Ru effectively modulates the morphology of Ce-BDC from nanorods to porous nanosheets. The WO3/Ru@CeO2 bilayer sensor is constructed by using WO3 nanofibers as the lower sensitive layer and Ru@CeO2 as the upper catalytic layer. At the operating temperature of 160 °C, the response value (Ra/Rg) of the WO3/Ru@CeO2 bilayer sensor to 5 ppm xylene is 37.04, which is obviously better than that of the WO3 nanofiber sensor. In addition, the sensor also reacted significantly to low concentrations of xylene, as low as 1 ppb. Additionally, the combination of online mass spectrometry and density functional theory was employed to validate the enhanced sensing performance arising from the synergistic mechanism between the catalytic and sensing materials. Hence, the work presents a new material for detecting ppb level BTEX through an effective bilayer structure design and material selection.

Assessing the impact of volatile organic compounds on cardiovascular health: Insights from the National Health and Nutrition Examination Survey 2011-2020

Volatile organic compounds (VOCs) are environmental pollutants that may negatively impact cardiovascular health. This study investigates the association between VOC mixtures, measured through urinary VOC metabolites (VOCMs), and cardiovascular health using Life's Essential 8 (LE8) scores. Data from the National Health and Nutrition Examination Survey (NHANES) 2011-2020 were analyzed for 2967 adults aged 20-79 years. Multiple statistical methods, including correlation analysis, variance inflation factor (VIF) analysis, quantile g-computation (q-gcomp), and Bayesian kernel machine regression (BKMR), were applied to assess the association between VOCMs and LE8 scores. Sensitivity analyses were conducted with different random seeds and subsampling techniques to confirm robustness. Correlation and VIF analyses revealed strong collinearity among VOCMs, highlighting the need for advanced models. Survey-weighted regression indicated that lower VOC exposure was associated with better cardiovascular health. Q-gcomp identified both positive and negative associations between individual VOCMs and LE8 scores, with some unexpected positive associations. BKMR highlighted the complex mixture effects of VOCMs on cardiovascular health. Sensitivity analyses confirmed the consistency of these findings. This study underscores the intricate relationship between VOC exposure and cardiovascular health and the necessity of advanced statistical methods for mixture analysis. Despite some unexpected findings, the results suggest that VOC exposure, as reflected by urinary VOCMs, is associated with adverse cardiovascular health outcomes. Further research is needed to clarify the biological mechanisms and implications of these associations.

Distinct baseline toxicity of volatile organic compounds (VOCs) in gaseous and liquid phases: Mixture effects and potential molecular mechanisms

Volatile organic compounds (VOCs) are significant pollutants found in various environments, posing health risks. Traditionally, the gaseous VOCs are adsorbed and eluted in liquid phases, and then subjected to toxicity testing, which deviates from the actual exposure scenarios of gaseous VOCs. How the physical states of VOCs (gaseous or liquid) affect their toxicity has not been well understood. This study examined the baseline toxicity of VOCs in both gaseous and liquid phases using a self-assembled passive colonization hydrogel (SAPCH) with luminous bacteria (Vibrio fischeri). The findings revealed that gaseous VOCs exhibited higher baseline toxicity than their liquid counterparts, attributed to the higher free energy and electronic activity of gaseous VOC molecules. Furthermore, the study elucidated that the differences in electronic transitions and energy gaps significantly impact the combined toxicity of VOC mixtures in different phases. Understanding these differences is crucial for assessing the real-world impact of VOCs on health and the environment.

Highly selective ethanol gas sensor based on CdS/Ti3C2T x MXene composites

Sensing of hazardous gases has an important role in ensuring safety in a variety of industries as well as environments. Mainly produced by the combustion of fossil fuels and other organic matter, ethanol is a dangerous gas that endangers human health and the environment. Stability and sensing sensitivity are major considerations when designing gas sensors. Here, a superior ethanol sensor with a high response and fast recovery was synthesized by "wrapping" CdS nanoparticles on metallic Ti3C2T x MXene using a simple method. CdS nanoparticles were uniformly covered on the Ti3C2T x MXene surface, forming a "rice crust"-like heterostructure. The sensor displayed good detection of ethanol gas at room temperature. Response signals up to 31% were obtained for ethanol molecules (20 ppm) with quick recovery (41 s). The performance of the ethanol sensor was evaluated across a range of concentrations (5-100 ppm) and relative humidity (60% and 90% RH) at room temperature. Our method could open up a new strategy for the development of ethanol sensors.

Synthesis of reusable hierarchical Pore PVDF-MIL-101(Cr) foam for Solid phase extraction of fluoroquinolones from water and its adsorption behavior for anionic and cationic dyes

In this study, a novel hierarchical pore MIL-101(Cr) foam (HPF-MIL-101) was designed and prepared using the sacrificial template method with NaCl as the sacrificial template. This method involved grinding, heating, and washing the NaCl template to produce HPF-MIL-101, with PVDF as the binder and MIL-101(Cr) as the adsorbent. This preparation process is both straightforward and cost-effective, avoiding the use or generation of any organic reagents, thereby offering an environmentally sustainable approach for producing metal-organic framework (MOF) composites. The prepared HPF-MIL-101 exhibited excellent adsorption capabilities for both anionic dye (methyl orange, MO) and cationic dye (methylene blue, MB). The adsorption process followed a pseudo-second-order kinetic model and Friedrich isotherm model, indicating a multilayer adsorption. This is further supported by the Weber-Morris intraparticle diffusion model, which divided the adsorption process into three stages. Furthermore, the adsorption process was consistent with the Freundlich isotherm model, with a correlation coefficient (r) greater than 0.96. HPF-MIL-101 can also be used as an adsorbent for solid phase extraction (SPE). Therefore, an SPE method combined with high-performance liquid chromatography (HPLC) was developed using HPF-MIL-101 as the adsorbent to analyze five fluoroquinolones (FQs) in water samples. This analytical method showed good linearity in the range of 30-2000 ng·mL-1, with excellent linear correlation coefficient (r = 0.9991-0.9999), reasonable extraction recoveries ranging from 80.39 to 112.7 % (RSD ≤ 7.9 %), and low limits of detection (8-30 ng·mL-1). Overall, the results indicated that HPF-MIL-101 not only had a simple, environment-friendly, and pollution-free preparation process but also can be reused for enrichment and detection of trace FQs in water. Thus, HPF-MIL-101 exhibits immense application potential in environmental pollutant removal and also provides a valuable reference for the preparation and application of other MOF composites.

Assessment of synergistic and antagonistic interactions between volatile compounds thymol, carvacrol, and eugenol diluted in solvents against Rhipicephalus microplus in in vitro tests

The cattle tick Rhipicephalus microplus is prevalent in tropical and subtropical regions, causing substantial economic losses due to its resistance to conventional acaricides. There is an urgent need to identify safe and effective new acaricidal agents. Essential oils and their volatile compounds are promising alternatives. Ensuring the use of optimal solvents or surfactants that do not compromise the acaricidal activity of these compounds during testing is crucial. This study aims to evaluate how compounds thymol, carvacrol and eugenol interact with xylol, methanol, ethanol, acetone, isopropyl alcohol, glycerol, dimethyl sulfoxide, castor oil, propylene glycol, vaseline, and Tween 80® to enhance (or to worse) their acaricidal efficacy against R. microplus. Larval mortality time were compared against one negative control (soybean oil) and two positive controls (commercial pour-on products). The experiments were conducted in 48-well polyethylene plates, with around 100 larvae immersed in 200 μl of each solvent at 100, 50, 25, 12.5, 6.25, 3.125 and 1.56% and diluted in soybean oil or water, according to solubility. Each volatile compound (Thymol, carvacrol and eugenol) was diluted in the tested solvents to assess larval mortality time. Xylol demonstrated the shortest larval mortality time, even at a minimum concentration (p < 0.05). In contrast, liquid vaseline exhibited the longest larval mortality time. When thymol, carvacrol, and eugenol were combined with xylol, they achieved the shortest larval mortality time. Conversely, when diluted in liquid vaseline they exhibited synergistic effects decreasing the mortality time. Tween 80® worsen the efficacy of thymol, carvacrol, and eugenol, resulting in prolonged larval mortality times. These findings emphasize the critical role of solvent selection, indicating the choice of solvent profoundly affects the formulation's effectiveness, directly influencing the activity of the active compounds.

Detection of VOCs and Biogenic Amines Through Luminescent Zn-Salen Complex-Tethered Pyrenyl Arms

Amines are produced through various industrial and biological processes, contributing significantly to atmospheric pollution, particularly in the troposphere. Moreover, amine-related pollution raises global concerns due to its detrimental effects on human health, environmental quality, and the preservation of animal species. Low-molecular-weight volatile amines, categorized as volatile organic compounds (VOCs), are present in the atmosphere, and they represent the main cause of air pollution. Biogenic amines, resulting from the natural decarboxylation of amino acids, are released into the environment from both natural and industrial sources. Several methods have been developed so far to detect amines in the environment. In this study, we present a novel fluorescent receptor based on a Zn-Salen complex, functionalized with pyrenyl moieties and a chiral diamine bridge, to enhance its affinity for a broad range of amines. Fluorescence titrations and density functional theory (DFT) calculations reveal and explain the high binding affinity of this receptor toward selected amines, demonstrating its potential as an effective tool for amine detection.

The Characteristics, Sources, and Health Risks of Volatile Organic Compounds in an Industrial Area of Nanjing

This study investigates the chemical complexity and toxicity of volatile organic compounds (VOCs) emitted from national petrochemical industrial parks and their effects on air quality in an industrial area of Nanjing, China. Field measurements were conducted from 1 December 2022, to 17 April 2023, focusing on VOC concentrations and speciations, diurnal variations, ozone formation potential (OFP), source identification, and associated health risks. The results revealed an average total VOC (TVOC) concentration of 15.9 ± 12.9 ppb and an average OFP of 90.1 ± 109.5 μg m-3. Alkanes constituted the largest fraction of VOCs, accounting for 44.1%, while alkenes emerged as the primary contributors to OFP, comprising 52.8%. TVOC concentrations peaked before dawn, a pattern attributed to early morning industrial activities and nighttime heavy vehicle operations. During periods classified as clean, when ozone levels were below 160 μg m-3, both TVOC (15.9 ± 12.9 ppb) and OFP (90.4 ± 110.0 μg m-3) concentrations were higher than those during polluted hours. The analysis identified the key sources of VOC emissions, including automobile exhaust, oil and gas evaporation, and industrial discharges, with additional potential pollution sources identified in adjacent regions. Health risk assessments indicated that acrolein exceeded the non-carcinogenic risk threshold at specific times. Moreover, trichloromethane, 1,3-butadiene, 1,2-dichloroethane, and benzene were found to surpass the acceptable lifetime carcinogenic risk level (1 × 10-6) during certain periods. These findings highlight the urgent need for enhanced monitoring and regulatory measures aimed at mitigating VOC emissions and protecting public health in industrial areas. In the context of complex air pollution in urban industrial areas, policymakers should focus on controlling industrial and vehicle emissions, which can not only reduce secondary pollution, but also inhibit the harm of toxic substances on human health.

A comprehensive review of covalent organic frameworks (COFs) and their derivatives in environmental pollution control

Covalent organic frameworks (COFs) have gained considerable attention due to their design possibilities as the molecular organic building blocks that can stack in an atomically precise spatial arrangement. Since the inception of COFs in 2005, there has been a continuous expansion in the product range of COFs and their derivatives. This expansion has led to the evolution of three-dimensional structures and various synthetic routes, propelling the field towards large-scale preparation of COFs and their derivatives. This review will offer a holistic analysis and comparison of the spatial structure and synthesis techniques of COFs and their derivatives. The conventional methods of COF synthesis (i.e., ultrasonic chemical, microwave, and solvothermal) are discussed alongside the synthesis strategies of new COFs and their derivatives. Furthermore, the applications of COFs and their derived materials are demonstrated in air, water, and soil pollution management such as gas capture, catalytic conversion, adsorption, and pollutant removal. Finally, this review highlights the current challenges and prospects for large-scale preparation and application of new COFs and the derived materials. In line with the United Nations Sustainable Development Goals (SDGs) and the needs of digital-enabled technologies (AI and machine learning), this review will encompass the future technical trends for COFs in environmental pollution control.

The production of methyl mercaptan is the main odor source of chicken manure treated with a vertical aerobic fermenter

The process of harmless treatment of livestock manure produces a large amount of odor, which poses a potential threat to human and livestock health. A vertical fermentation tank system is commonly used for the environmentally sound treatment of chicken manure in China, but the composition and concentration of the odor produced and the factors affecting odor emissions remain unclear. In this study, we investigated the types and concentrations of odors produced in the mixing room (MR), vertical fermenter (VF), and aging room (AR) of the system, and analyzed the effects of bacterial communities and metabolic genes on odor production. The results revealed that 34, 26 and 26 odors were detected in the VF, MR and AR, respectively. The total odor concentration in the VF was 66613 ± 10097, which was significantly greater than that in the MR (1157 ± 675) and AR (1143 ± 1005) (P < 0.001), suggesting that the VF was the main source of odor in the vertical fermentation tank system. Methyl mercaptan had the greatest contribution to the odor produced by VF, reaching 47.82%, and the concentration was 0.6145 ± 0.2164 mg/m3. The abundance of metabolic genes did not correlate significantly with odor production, but PICRUSt analysis showed that cysteine and methionine metabolism involved in methyl mercaptan production was significantly more enriched in MR and VF than in AR. Bacillus was the most abundant genus in the VF, with a relative abundance significantly greater than that in the MR (P < 0.05). The RDA results revealed that Bacillus was significantly and positively correlated with methyl mercaptan. The use of large-scale aerobic fermentation systems to treat chicken manure needs to focused on the production of methyl mercaptan.

The effect of dietary oxidation balance scores and volatile organic compounds exposures on inflammation

BACKGROUND

Inflammation is a significant factor in adverse health outcomes, but the combined effects of diets with varying oxidation levels and exposure to volatile organic compounds (VOCs) on inflammation are not well understood. This study aimed to elucidate the effects of the recognized Dietary Oxidative Balance Score (DOBS) and five VOCs on the systemic immune-inflammation index (SII) and C-reactive protein (CRP).

METHODS

This cross-sectional study included data from participants in three cycles (2003-2004, 2005-2006, 2009-2010) of the National Health and Nutrition Examination Survey (NHANES). We used Spearman correlation, logistic regression, and trend tests to explore the associations between DOBS, VOCs, SII, and CRP. Additionally, we conducted restricted cubic spline (RCS) analysis to assess dose-response relationships between exposure and effect. G-computation and stratified analyses were performed to further elucidate these associations.

RESULTS

We included 7033 eligible participants, with 48.8 % males and 51.2 % females. Spearman correlation revealed that DOBS was negatively correlated with SII and CRP, while the five VOCs were positively correlated with SII and CRP. Although fully adjusted logistic regression models did not yield statistically significant results, trend tests indicated a gradual decrease in SII and CRP with increasing DOBS, a finding validated by RCS analysis. G-computation results demonstrated that the combined effect of DOBS and VOCs on inflammation was positive, with DOBS exerting a negative effect and benzene, ethylbenzene, and 1,4-dichlorobenzene exerting positive effects. Stratified analysis showed that maintaining physical activity significantly influenced the effects of DOBS and VOCs on inflammation.

CONCLUSION

This study suggests that adjusting dietary structure and reducing daily exposure to VOCs can effectively reduce inflammation in the body.

Exploring the impact of occupational exposure: A study on cardiovascular autonomic functions of male gas station attendants in Sri Lanka

Fuel dispensing at fuel stations is performed manually by unprotected male gas station attendants in Sri Lanka, who have long working hours. These workers are exposed to hydrocarbon fuels associated with multiple health effects by modulation of the autonomic nervous system. This study was performed to determine cardiovascular autonomic functions among fuel pump attendants in Sri Lanka. Fuel pump attendants (n = 50) aged between 19 and 65 years were identified for the study from seven fuel stations. They were compared with age- and gender-matched controls (n = 46) without occupational exposure to fuel. A physical examination was performed before the autonomic function and heart rate variability (HRV) assessment. There were no significant differences in weight, height, or BMI between the study and the control populations (p > 0.05). Both the systolic blood pressure (SBP) (Mann Whitney U (MWU) = 743.5, p = 0.003) and diastolic blood pressure (DBP) (MWU = 686.5, p = 0.001) were significantly higher among the gas station attendants compared to controls. Valsalva ratio was significantly higher among the study group (MW U = 874.00, p = 0.043) compared to controls. The HRV analysis showed significantly higher SDNN and SD2 (MWU = 842.00, p = 0.034, and MWU = 843.50, p = 0.035 respectively) among the gas station attendants compared to controls. The changes to the cardiovascular autonomic parameters among those exposed to fuel vapor as a gas station attendant indicate an increase in sympathetic outflow to the vessels. In the occupational setting as fuel pump attendants need periodic monitoring.

Chemical exposure from the Hebei spirit oil spill accident and its long-term effects on mental health

While evidence indicates that exposure to oil spill incidents can affect mental health, it is unclear whether the mental health effects result from the incident itself or from exposure to associated chemicals. Oil contains chemicals that can impact mental health and these chemicals may have long-term effects due to their persistence in the environment. To address the gap in current knowledge, we conducted cross-sectional and prospective analyses of data from adults who participated in the Health Effects of the Hebei Spirit Oil Spill study. To assess chemical exposure from oil spills, we used indirect exposure indicators such as distance from the contaminated oil band to residences and duration of clean-up work, along with direct exposure indicators such as urine metabolite concentrations of volatile organic compounds and polycyclic aromatic hydrocarbons. Mental health assessments covered posttraumatic stress disorder (PTSD), depression, state anxiety, and trait anxiety. In the cross-sectional analyses, all four mental health issues were found to be associated with proximity to the oil band (p-value<0.05) and showed a positive association with clean-up work duration (p-value<0.05). Cox regression analysis revealed that higher urinary t, t-muconic acid levels were associated with an increased risk of depression (Hazard Ratio [HR] = 1.55, 95 % Confidence Interval [CI] = 1.05-2.28), and elevated 1-hydroxypyrene levels increased the risk of PTSD (HR = 1.60, 95 % CI = 1.03-2.48). Additionally, higher urinary 2-naphthol levels were associated with increased state anxiety (HR = 1.39, 95 % CI = 1.00-1.93) and trait anxiety (HR = 1.64, 95 % CI = 1.15-2.32). These associations persisted even after controlling for distance and duration variables related to psychosocial exposure. Our findings suggest that environmental disaster response plans should prioritize minimizing chemical exposure while also considering the duration and nature of the mental health impacts.

Aqueous VOCs in complex water environment of oil exploitation sites: Spatial distribution, migration flux, and risk assessment

Pollution of the aqueous environment by volatile organic compounds (VOCs) has caused increasing concerns. However, the occurrence and risks of aqueous VOCs in oil exploitation areas remain unclear. Herein, spatial distribution, migration flux, and environmental risks of VOCs in complex surface waters (including River, Estuary, Offshore and Aquaculture areas) were investigated at a typical coastal oil exploitation site. Among these surface waters, River was the most polluted area, and 1,2-Dichloropropane-which emerges from oil extraction activities-was the most prevalent VOC. Positive matrix factorization showed that VOCs pollution sources changed from oil exploitation to offshore disinfection activities along River, Estuary, Offshore and Aquaculture areas. Annual volatilization of VOCs to the atmosphere was predicted to be ∼34.42 tons, and rivers discharge ∼23.70 tons VOCs into the Bohai Sea annually. Ecological risk assessment indicated that Ethylbenzene and Bromochloromethane posed potential ecological risks to the aquatic environment, while olfactory assessment indicated that VOCs in surface waters did not pose an odor exposure risk. This study provides the first assessment of the pollution characteristics of aqueous VOCs in complex aqueous environments of oil exploitation sites, highlighting that oil exploitation activities can have nonnegligible impacts on VOCs pollution profiles.

Innovative Approach for Human Semen Quality Assessment Based on Volatilomics

The volatilome profile of some biofluids (blood, urine, and human semen) identified by Solid-Phase Microextraction-Gas Chromatography/Mass Spectrometry (SPME-GC/MS) and collected from young men living in two high-pollution areas in Italy, i.e., Land of Fires and Valley of Sacco River, have been coupled to sperm parameters obtained by spermiogram analysis to build general multiple regression models. Panels of volatile organic compounds (VOCs) have been selected to optimize the models and used as predictive variables to estimate the different sperm quality parameters (sperm cell concentration, total and progressive motility/immotile cells, total/head/neck/tail morphology anomalies, semen round cell concentration). The results of the multiple linear regression models based on the different subgroups of data joining VOCs from one/two or three biofluids have been compared. Surprisingly, the models based on blood and urine VOCs have allowed an excellent estimate of spermiogram values, paving the way towards a new method of indirect evaluation of semen quality and preventive screening. The significance of VOCs in terms of toxicity and dangerousness was discussed with the support of chemical databases available online.

Unveiling the hidden impact: How biodegradable microplastics influence CO2 and CH4 emissions and Volatile Organic Compounds (VOCs) profiles in soil ecosystems

Biodegradable plastics promise eco-friendliness, yet their transformation into microplastics (bio-MPs) raises environmental alarms. However, how those bio-MPs affect the greenhouse gases (GHGs) and volatile organic compounds (VOCs) in soil ecosystems remains largely unexplored. Here, we investigated the effects of diverse bio-MPs (PBAT, PBS, and PLA) on GHGs and VOCs emission in typical paddy or upland soils. We monitored the carbon dioxide (CO2) and methane (CH4) fluxes in-situ using the self-developed portable optical gas sensor and analyzed VOC profiles using a proton-transfer reaction mass spectrometer (PTR-MS). Our study has revealed that, despite their biodegradable nature, bio-MPs do not always promote soil GHG emissions as previously thought. Specifically, PBAT and PLA significantly increased CO2 and CH4 emissions up to 1.9-7.5 and 115.9-178.5 fold, respectively, compared to the control group. While PBS exhibited the opposite trend, causing a decrease of up to 39.9% for CO2 and up to 39.9% for CH4. In addition, different types of bio-MPs triggered distinct soil VOC emission patterns. According to the Mann-Whitney U-test and Partial Least Squares Discriminant Analysis (PLS-DA), a recognizable VOC pattern associated with different bio-MPs was revealed. This study claims the necessity of considering polymer-specific responses when assessing the environmental impact of Bio-MPs, and providing insights into their implications for climate change.